Make sure that, for every living SCEV, we have all its direct
operand tracking it as their user.
Differential Revision: https://reviews.llvm.org/D112402
Reviewed By: reames
Simplify "LUI+SLLI+ADDI+SLLI" and "LUI+ADDIW+SLLI+ADDI+SLLI" to
"LUI+ADDIW+SLLIUW" to reduce total instruction amount.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D111933
The scheduler should set critical/excess register usage thresholds that
are guided by the maximum possible occupancy for the function. This
change is focused on setting proper lower bounds on register usage which
we would typically only see when a specific number of maximum waves is
requested with the "waves-per-eu" attribute, or by setting
"amdgpu-num-vgpr|sgpr" directly. This was broken previously. I have a
follow-on patch that will address issues with the scheduler not
targeting correct upper bounds on register usage which is typical with
launch bounds and min "waves-per-eu".
Changes by this patch:
Set the initial critical register usage thresholds to minimum values
that are determined by the maximum possible occupancy for the function,
or the number of allocatable registers, whichever is lower.
Avoid unisgned overflow if register limits are lower than the register
tracking "ErrorMargin", I.e. when using stress-regalloc=2.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D112373
Otherwise, ODRUniquing would map some member method/variable MDNodes
to have enum type DIScope, resulting in invalid debug info and bad
DWARF.
- Add a Verifier check that when a 'scope:' operand is an ODR type that is not an enum.
- Makes ODRUniquing apply to only ODR types with the same tag so that the debuginfo/DWARF is well-formed.
Reviewed By: probinson, aprantl
Differential Revision: https://reviews.llvm.org/D111770
Use RdxDesc->getOpcode instead of getUnderlingInstr()->getOpcode.
Move the code which finds Kind and IsOrdered to be outside the for loop
since neither of these change with the vector part.
Differential Revision: https://reviews.llvm.org/D112547
It was discovered that an extra register COPY remained when expanding a
(variable length) memory operation with a loop and there was another use of
the involved address register(s) afterwards.
A simple fix for this is to COPY the address registers before the loop and
use that new vreg instead.
Review: Ulrich Weigand
Differential Revision: https://reviews.llvm.org/D112065
The final reduction nodes should not be reordered, the order does not
matter for reductions. Also, it might be profitable to vectorize smaller
reduction trees, reduction cost may compensate small tree cost.
Part of D111574
Differential Revision: https://reviews.llvm.org/D112467
We were bailing out of creating 24-bit muls for results wider than 32
bits in AMDGPUCodeGenPrepare. With the 24-bit mulhi intrinsic, this
change teaches AMDGPUCodeGenPrepare to generate the 48-bit mul
correctly.
Differential Revision: https://reviews.llvm.org/D112395
These intrinsics maps to the 24-bit v_mul_hi instructions.
This change also fixes an incorrect assumption on the associativity of
24-bit mulhi in its SDNode record in tblgen.
Differential Revision: https://reviews.llvm.org/D112394
The combine asserted if constants could not be represented as uint64_t.
Use APInts to fix this.
Differential Revision: https://reviews.llvm.org/D112416
All instructions must have a correct size value close to emission when
SystemZLongBranch runs, or a necessary branch relaxation may be missed.
This patch also adds an assert for instruction sizes in SystemZLongBranch.
Review: Ulrich Weigand
The function simplifyOnce only calls simplifyOnceImpl and does nothing else.
Having this separate helper makes no sense. Removing it.
Patch by Dmitry Bakunevich!
Differential Revision: https://reviews.llvm.org/D112517
Reviewed By: mkazantsev
When peeling a loop, we assume that the latch has a `br` terminator and that
all loop exits are either terminated with an `unreachable` or have a terminating
deoptimize call. So when we peel off the 1st iteration, we change the IDom of
all loop exits to the peeled copy of `NCD(IDom(Exit), Latch)`. This works now,
but if we add logic to support loops with exits that are followed by a block
with an `unreachable` or a terminating deoptimize call, changing the exit's idom
wouldn't be enough and DT would be broken.
For example, let `Exit1` and `Exit2` are loop exits, and each of them
unconditionally branches to the same `unreachable` terminated block. So neither
of the exits dominates this unreachable block. If we change the IDoms of the
exits to some peeled loop block, we don't update the dominators of the unreachable
block. Currently we just don't get to the peeling logic, saying that we can't peel
such loops.
Previously we stored exits' IDoms in a map before peeling a loop and then, after
peeling off one iteration, we changed their IDoms.
Now we use the same logic not only for exits but for all non-loop blocks dominated
by the loop.
So when we add logic to support peeling loops with exits which branch, for example,
to an unreachable-terminated block, we would update the IDoms not only for exits,
but for their successors.
Patch by Dmitry Makogon!
Differential Revision: https://reviews.llvm.org/D111611
Reviewed By: mkazantsev, nikic
This can avoid a vector add and a constant pool load. Or an explicit broadcast in case of non-constant.
Also reverse the transform any time we encounter a constant index addend that can't be moved to base. In that case pull the constant from base into the index. This reduces code size needed for the displacement since we needed the index add anyway. Limit this to scale of 1 to avoid divisibility and wrap issues.
Authored by Craig.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D111595
Avoid naming some Expected<T> values in the Bitcode reader by using
takeError() and moveInto() more often. This follows the smaller set of
changes included in 2410fb4616.
Removed references to `sanity check` in `PPCBranchCoalescing.cpp` code comments.
No word substitution made in this case, as the comments and code following illustrated are
sufficient IMO.
Reviewed By: quinnp
Differential Revision: https://reviews.llvm.org/D112452
getShiftAmountTyForConstant is a special helper that changes the
shift amount to i32 if the type chosen by
TargetLowering::getShiftAmountTy can't represent all possible values.
This is needed to satisfy an assert in SelectionDAG::getNode.
It requires additional consideration to know when this helper should be used.
I'm not sure that we are always using it when we should.
This patch merges the getShiftAmountTyForConstant handling into
TargetLowering::getShiftAmountTy so we don't need to think about it
anymore.
Technically this may slightly increase compile times since the majority
of callers of getShiftAmountTy won't need this. Hopefully, this isn't
an issue in practice.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112469
Always insert values into ExprValueMap, and instead skip using them
in SCEVExpander if poison-generating flags have been lost. This
ensures that all values that are in ValueExprMap are also in
ExprValueMap, so we can use the latter to invalidate the former.
This change is probably not entirely NFC for the case where
originally the SCEV had no nowrap flags but they were inferred
later, in which case that would now allow reusing the existing
value for expansion.
Differential Revision: https://reviews.llvm.org/D112389
There are a few STL containers hanging around that can become DenseMaps,
SmallVectors and similar. This recovers a modest amount of compile time
performance.
While I'm here, adjust the bit layout of ValueIDNum: this was always
supposed to act like a value type, however it seems that clang doesn't
compile the comparison functions to act that way. Add a uint64_t to a
union that explicitly aliases the bitfields, so that we can compare the
whole value as a single integer.
Differential Revision: https://reviews.llvm.org/D112333
This patch is like D111627 -- instead of calculating IDF for every location
on the stack, only do it for the smallest units of interference, and copy
the PHIs for those units to any aliases.
The test added runs placeMLocPHIs directly, and tests that:
* A def of the lower 8 bits of a stack slot causes all aliasing regs to
have PHIs placed,
* It doesn't cause the equivalent location to x86's $ah, which isn't
aliased, to have a PHI placed.
Differential Revision: https://reviews.llvm.org/D112324
The recently added logic to canonicalize exit conditions to unsigned relies on facts which hold about the use (i.e. exit test). Applying this blindly to the icmp is not legal, as there may be another use which never reaches the exit. Restrict ourselves to case where we have a single use.
All but 2 of the vector builtins are only used by clang_builtin_alias.
When using clang_builtin_alias, the type string of the builtin is never
checked. Only the types in the function definition used for the alias
are checked.
This patch takes advantage of this to share a single builtin for
many different types. We already used type overloads on the IR intrinsic
so the codegen for the builtins that are being merge were already
the same. This extends the type overloading to the builtins.
I had to make a few tweaks to make this work.
-Floating point vector-vector vmerge now uses the vmerge intrinsic
instead of the vfmerge intrinsic. New isel patterns and tests are
added to support this.
-The SemaChecking for the immediate of vset_v/vget_v has been removed.
Determining the valid range is harder now. I've added masking to
ManualCodegen to ensure valid IR for invalid input.
This reduces the number of builtins from ~25000 to ~1100.
Reviewed By: HsiangKai
Differential Revision: https://reviews.llvm.org/D112102
During register allocation, some instructions can have stack spills fused
into them. It means that when vregs are allocated on the stack we can
convert:
SETCCr %0
DBG_VALUE %0
to
SETCCm %stack.0
DBG_VALUE %stack.0
Unfortunately instruction referencing finds this harder: a store to the
stack doesn't have a specific operand number, therefore we don't substitute
the old operand for a new operand, and the location is dropped. This patch
implements a solution: just recognise the memory operand attached to an
instruction with a Special Number (TM), and record a substitution between
the old value and the new one.
This patch adds substitution code to InlineSpiller to record such fused
spills, and tracking in InstrRefBasedLDV to recognise such values, and
produce the value numbers for them. Everything to do with the movement of
stack-defined values is already handled in InstrRefBasedLDV.
Differential Revision: https://reviews.llvm.org/D111317
Before the code would crash with "unhandled opcode in
isAArch64FrameOffsetLegal" when there was a spill from extractelement.
Fixes pr52249
Differential Revision: https://reviews.llvm.org/D112311
D109746 made BasicAA use range information to determine the
minimum/maximum GEP offset. However, it was limited to the case of
a single variable index. This patch extends support to multiple
indices by adding all the ranges together.
Differential Revision: https://reviews.llvm.org/D112378
Need to change the order of the reduction/binops args pair vectorization
attempts. Need to try to find the reduction at first and postpone
vectorization of binops args. This may help to find more reduction
patterns and vectorize them.
Part of D111574.
Differential Revision: https://reviews.llvm.org/D112224
This patch swaps two lines -- the CurSucc reference can be invalidated
by the call to DFS.push_back, therefore that should happen last. The
usual hat-tip to asan for catching this.
This patch also swaps an ealier call to ToAdd.insert and DFS.push_back,
where a stable iterator (from successors()) is being used. This isn't
strictly necessary, but is good for consistency and avoiding readers
asking themselves why the two code portions have a different order.
(i8 X ^ 128) & (i8 X s>> 7) --> usubsat X, 128
As suggested in D112085, we can substitute 'xor' with 'add'
in this pattern, and it is logically equivalent:
https://alive2.llvm.org/ce/z/eJtWWC
We canonicalize to 'xor' in IR, but SDAG does not do that
(and it probably should not - https://llvm.org/PR52267 ), so
it is possible to see either pattern in codegen. Note that
'sub' is a another potential pattern, but that is
canonicalized to 'add' in DAGCombiner, so we don't need to
worry about that variation.
Differential Revision: https://reviews.llvm.org/D112377
This patch enables the use of reciprocal estimates for SVE
when both the -Ofast and -mrecip flags are used.
Reviewed By: david-arm, paulwalker-arm
Differential Revision: https://reviews.llvm.org/D111657
We observe a hang within iterativelySimplifyCFG due to infinite
loop execution. Currently, there is no limit to this loop, so
in case of bug it just works forever. This patch adds an assert
that will break it after 1000 iterations if it didn't converge.
Currently strip.invariant/launder.invariant are handled by
constructing constant expressions with the intrinsics skipped.
This takes an alternative approach of accumulating the offset
using stripAndAccumulateConstantOffsets(), with a flag to look
through invariant.group intrinsics.
Differential Revision: https://reviews.llvm.org/D112382
At the moment a dummy entry block is created at the beginning of VPlan
construction. This dummy block is later removed again.
This means it is not easy to identify the VPlan header block in a
general fashion, because during recipe creation it is the single
successor of the entry block, while later it is the entry block.
To make getting the header easier, just skip creating the dummy block.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D111299
%3:gpr32 = ORRWrs $wzr, %2, 0
%4:gpr64 = SUBREG_TO_REG 0, %3, %subreg.sub_32
If AArch64's 32-bit form of instruction defines the source operand of ORRWrs,
we can remove the ORRWrs because the upper 32 bits of the source operand are
set to zero.
Differential Revision: https://reviews.llvm.org/D110841
Mass forgetMemoizedResults can be done more efficiently than bunch
of individual invocations of helper because we can traverse maps being
updated just once, rather than doing this for each invidivual SCEV.
Should be NFC and supposedly improves compile time.
Differential Revision: https://reviews.llvm.org/D112294
Reviewed By: reames
When forgetting multiple SCEVs, rather than doing this one by one, we can
instead use mass updates. We plan to make them more efficient than they
are now, potentially improving compile time.
Differential Revision: https://reviews.llvm.org/D111602
Reviewed By: reames
This patch changes signature of forgetMemoizedResults to be able to work with
multiple SCEVs. Usage will come in follow-ups. We also plan to optimize it in the
future to work faster than individual invalidation updates. Should not change
behavior in any sense.
Split-off from D111602.
Differential Revision: https://reviews.llvm.org/D112293
Reviewed By: reames
Follow-up from D112295, suggested by Nikita: we can avoid tracking
users of SCEVConstants because dropping their cached info is unlikely
to give any new prospects for fact inference, and it should not introduce
any correctness problems.
This patch introduces API that keeps track of SCEVs users of
another SCEVs, required to handle invalidations of users along
with operands that comes in follow-up patches.
Differential Revision: https://reviews.llvm.org/D112295
Reviewed By: reames
Add a new preparation pattern in PPCLoopInstFormPrep pass to reduce register
pressure.
Reviewed By: jsji
Differential Revision: https://reviews.llvm.org/D108750
This extends `optimizeCompareInstr` to continue the backwards search
when it reached the beginning of a basic block. If there is a single
predecessor block then we can just continue the search in that block and
mark the EFLAGS register as live-in.
Differential Revision: https://reviews.llvm.org/D110862
This changes the first part of `optimizeCompareInstr` being split into a
loop with a forward scan for cases that re-use zero flags from a
producer in case of compare with zero and a backward scan for finding an
instruction equivalent to a compare.
The code now uses a single backward scan searching for the next
instructions that reads or writes EFLAGS.
Also:
- Add comments giving examples for the 3 cases handled.
- Check `MI` which contains the result of the zero-compare cases,
instead of re-checking `IsCmpZero`.
- Tweak coding style in some loops.
- Add new MIR based tests that test the optimization in isolation.
This also removes a check for flag readers in situations like this:
```
= SUB32rr %0, %1, implicit-def $eflags
... we no longer stop when there are $eflag users here
CMP32rr %0, %1 ; will be removed
...
```
Differential Revision: https://reviews.llvm.org/D110857
The LangRef clearly states that branching on a undef or poison value is immediate undefined behavior, but historically, we have not been consistent about implementing that interpretation in the optimizer. Historically, we used (in some cases) a more relaxed model which essentially looked for provable UB along both paths which was control dependent on the condition. However, we've never been 100% consistent here. For instance SCEV uses the strong model for increments which form AddRecs (and only addrecs).
At the moment, the last big blocker for finally making this switch is enabling the fix landed in D106041. Loop unswitching (in it's classic form) is incorrect as it creates many "branch on poisons" when unswitching conditions originally unreachable within the loop.
This change adds a flag to value tracking which allows to easily test the optimization potential of treating branch on poison as immediate UB. It's intended to help ease work on getting us finally through this transition and avoid multiple independent rediscovers of the same issues.
Differential Revision: https://reviews.llvm.org/D112026
Fixes a crash observed by oss-fuzz in 39934. Issue at hand is that code expects a pattern match on m_Mul to imply the operand is a mul instruction, however mul constexprs are also valid here.
As this API is now internally offset-based, we can accept a starting
offset and remove the need to create a temporary bitcast+gep
sequence to perform an offset load. The API now mirrors the
ConstantFoldLoadFromConst() API.
The functionality of this method is already covered by
computeExitCountExhaustively() in a more general fashion. It was
added at a time when exhaustive exit count calculation did not
support constant folding loads yet. I double checked that dropping
this code causes no binary changes in test-suite.
Differential Revision: https://reviews.llvm.org/D112343
Commit 8fa3e8fa14 added an implicit REP prefix to all VIA PadLock
instructions, but GNU as doesn't add one to xstore, only all the others.
This resulted in a kernel panic regression in FreeBSD upon updating to
LLVM 11 (https://bugs.freebsd.org/259218) which includes the commit in
question. This partially reverts that commit.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D112355
GEP indices larger than the GEP index size are implicitly truncated
to the index size. BasicAA currently doesn't model this, resulting
in incorrect alias analysis results.
Fix this by explicitly modelling truncation in CastedValue in the
same way we do zext and sext. Additionally we need to disable a
number of optimizations for truncated values, in particular
"non-zero" and "non-equal" may no longer hold after truncation.
I believe the constant offset heuristic is also not necessarily
correct for truncated values, but wasn't able to come up with a
test for that one.
A possible followup here would be to use the new mechanism to
model explicit trunc as well (which should be much more common,
as it is the canonical form). This is straightforward, but omitted
here to separate the correctness fix from the analysis improvement.
(Side note: While I say "index size" above, BasicAA currently uses
the pointer size instead. Something for another day...)
Differential Revision: https://reviews.llvm.org/D110977
This can merge the acceptable ranges based on the call graph, rather
than the simple application of the attribute. Remove the handling from
the old pass.
Run post-RA SIShrinkInstructions just before post-RA scheduling, instead
of afterwards. After the fixes in D112305 and D112317 this seems to make
no difference, but it paves the way for scheduler tweaks that are
sensitive to the e32 vs e64 encoding of VALU instructions.
Differential Revision: https://reviews.llvm.org/D112341
As described in the comment, the way we change vcc to vcc_lo in these
operands confuses addPhysRegDataDeps into treating them as implicit
pseudo operands. Fix this by setting the correct latency from the
SchedModel after addPhysRegDataDeps wrongly set it to 0.
Differential Revision: https://reviews.llvm.org/D112317
This removes a condition and the corresponding FIXME comment, because
the Hexagon assertion it refers to has apparently been fixed, probably
by D76134.
NFCI. This just gives targets the opportunity to adjust latencies that
were set to 0 by the generic code because they involve "implicit pseudo"
operands.
Differential Revision: https://reviews.llvm.org/D112306
Sometimes we generate code that writes to a subregister, then spills /
restores a super-register to the stack, for example:
$eax = MOV32ri 0
MOV64mr $rsp, 1, $noreg, 16, $noreg, $rax
$rcx = MOV64rm $rsp, 1, $noreg, 8, $noreg
This patch takes a different approach: it adds another index to
MLocTracker that identifies a size/offset within a stack slot. A location
on the stack is then a pari of {FrameIndex, SlotNum}. Spilling and
restoring now involves pairing up the src/dest register numbers, and the
dest/src stack position to be transferred to/from. Location coverage
improves as a result, compile-time performance decreases, alas.
One limitation is that if a PHI occurs inside a stack slot:
DBG_PHI %stack.0, 1
We don't know how large the resulting value is, and so might have
difficulty picking which value to use. DBG_PHI might need to be augmented
in the future with such a size.
Unit tests added ensure that spills and restores correctly transfer to
positions in the Location => Value map, and that different register classes
written to the stack will correctly clobber all other positions in the
stack slot.
Differential Revision: https://reviews.llvm.org/D112133
We might be promoting a large non-power of 2 type and the new type
may need to be split. Once we split it we may have a ctlz/cttz/ctpop
instruction for the split type.
I'm also concerned that we may create large shifts with shift amounts
that are too small.
EXTRACT_SUBVECTOR indices are always constant, we don't need to check for ConstantSDNode, we should just use getConstantOperandVal which will assert for the constant.
The logic in this patch is that if we find a comparison which would be unsigned except for when the loop is infinite, and we can prove that an infinite loop must be ill defined, we can still make the predicate unsigned.
The eventual goal (combined with a follow on patch) is to use the fact the loop exits to remove the zext (see tests) entirely.
A couple of points worth noting:
* We loose the ability to prove the loop unreachable by committing to the must exit interpretation. If instead, we later proved that rhs was definitely outside the range required for finiteness, we could have killed the loop entirely. (We don't currently implement this transform, but could in theory, do so.)
* simplifyAndExtend has a very limited list of users it walks. In particular, in the examples is stops at the zext and never visits the icmp. (Because we can't fold the zext to an addrec yet in SCEV.) Being willing to visit when we haven't simplified regresses multiple tests (seemingly because of less optimal results when computing trip counts). D112170 explores fixing that, but - at least so far - appears to be too expensive compile time wise.
Differential Revision: https://reviews.llvm.org/D111836
This patch adds some unit tests for the machine-location transfer-function
building parts of InstrRefBasedLDV: i.e., test that if we feed some MIR
into the transfer-function building code, does it create the correct
transfer function.
There are a number of minor defects that get corrected in the process:
* The unit test was selecting the x86 (i.e. 32 bit) backend rather than
x86_64's 64 bit backend,
* COPY instructions weren't actually having their subregister values
correctly represented in the transfer function. Subregisters were being
defined by the COPY, rather than taking the value in the source register.
* SP aliases were at risk of being clobbered, if an SP subregister was
clobbered.
Differential Revision: https://reviews.llvm.org/D112006
Instead of returning a bool to indicate success and a separate
SDValue, return the SDValue and have the callers check if it is
null.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112331
This follows up on D111023 by exporting the generic "load value
from constant at given offset as given type" and using it in the
store to load forwarding code. We now need to make sure that the
load size is smaller than the store size, previously this was
implicitly ensured by ConstantFoldLoadThroughBitcast().
Differential Revision: https://reviews.llvm.org/D112260
Make use of the getGEPIndicesForOffset() helper for creating GEPs.
This handles arrays as well, uses correct GEP index types and
reduces code duplication.
Differential Revision: https://reviews.llvm.org/D112263
Expanding these requires multiple constants. If we promote during type
legalization when they'll end up getting expanded in LegalizeDAG, we'll
use larger constants. These constants may be harder to materialize.
For example, 64-bit constants on 64-bit RISCV are very expensive.
This is similar to what has already been done to BSWAP and BITREVERSE.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112268
This pseudo is expanded very late (AsmPrinter) and therefore has to have a
correct size value, or the branch relaxation pass may make a wrong decision.
Review: Ulrich Weigand
This will allow us to reuse existing interleaved load logic in
lowerInterleavedLoad that exists for neon types, but for SVE fixed
types.
The goal eventually will be to replace the existing ld<n> intriniscs
with these, once a migration path has been sorted out.
Differential Revision: https://reviews.llvm.org/D112078
By definition, interleaving load of stride N means:
load N*VF elements, and shuffle them into N VF-sized vectors,
with 0'th vector containing elements `[0, VF)*stride + 0`,
and 1'th vector containing elements `[0, VF)*stride + 1`.
Example: https://godbolt.org/z/df561Me5E (i64 stride 4 vf 2 => cost 6)
Now, not fully interleaved load, is when not all of these vectors is demanded.
So at worst, we could just pretend that everything is demanded,
and discard the non-demanded vectors. What this means is that the cost
for not-fully-interleaved group should be not greater than the cost
for the same fully-interleaved group, but perhaps somewhat less.
Examples:
https://godbolt.org/z/a78dK5Geq (i64 stride 4 (indices 012u) vf 2 => cost 4)
https://godbolt.org/z/G91ceo8dM (i64 stride 4 (indices 01uu) vf 2 => cost 2)
https://godbolt.org/z/5joYob9rx (i64 stride 4 (indices 0uuu) vf 2 => cost 1)
Right now, for such not-fully-interleaved loads we just use the costs
for fully-interleaved loads. But at least **in general**,
that is obviously overly pessimistic, because **in general**,
not all the shuffles needed to perform the full interleaving
will end up being live.
So what this does, is naively scales the interleaving cost
by the fraction of the live members. I believe this should still result
in the right ballpark cost estimate, although it may be over/under -estimate.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112307
This doesn't have any effect on codegen now, but it might do in the
future if we shrink instructions before post-RA scheduling, which is
sensitive to live vs dead defs.
Differential Revision: https://reviews.llvm.org/D112305
parseFunctionName allowed a default null pointer, despite it being dereferenced immediately to be used as a reference and that all callers were taking the address of an existing reference.
Fixes static analyzer warning about potential dereferenced nulls
Optimize the iterator comparison logic to compare Current.data()
pointers. Use std::tie for assignments from std::pair. Replace
the custom class with a function returning iterator_range.
Differential Revision: https://reviews.llvm.org/D110535
IRBuilder has been updated to support preserving metdata in a more
general manner. This patch adds `LLVMAddMetadataToInst` and
deprecates `LLVMSetInstDebugLocation` in favor of the more
general function.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D93454
This patch fixes a codegen bug, the test for which was introduced in
D112223.
When merging VSETVLIInfo across blocks, if the 'exit' VSETVLIInfo
produced by a block is found to be compatible with the VSETVLIInfo
computed as the intersection of the 'exit' VSETVLIInfo produced by the
block's predecessors, that blocks' 'exit' info is discarded and the
intersected value is taken in its place.
However, we have one authority on what constitutes VSETVLIInfo
compatibility and we are using it in two different contexts.
Compatibility is used in one context to elide VSETVLIs between
straight-line vector instructions. But compatibility when evaluated
between two blocks' exit infos ignores any info produced *inside* each
respective block before the exit points. As such it does not guarantee
that a block will not produce a VSETVLI which is incompatible with the
'previous' block.
As such, we must ensure that any merging of VSETVLIInfo is performed
using some notion of "strict" compatibility. I've defined this as a full
vtype match, but this is perhaps too pessimistic. Given that test
coverage in this regard is lacking -- the only change is in the failing
test -- I think this is a good starting point.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D112228
When I playing with Coroutines, I found that it is possible to generate
following IR:
```
%struct = alloca ...
%sub.element = getelementptr %struct, i64 0, i64 index ; index is not
%zero
lifetime.marker.start(%sub.element)
% use of %sub.element
lifetime.marker.end(%sub.element)
store %struct to xxx ; %struct is escaping!
<suspend points>
```
Then the AllocaUseVisitor would collect the lifetime marker for
sub.element and treat it as the lifetime markers of the alloca! So it
judges that the alloca could be put on the stack instead of the frame by
judging the lifetime markers only.
The root cause for the bug is that AllocaUseVisitor collects wrong
lifetime markers.
This patch fixes this.
Reviewed By: lxfind
Differential Revision: https://reviews.llvm.org/D112216
Transformations may strip the attribute from the
argument, e.g. for unused, which will result in
shadow offsets mismatch between caller and
callee.
Stripping noundef for used arguments can be
a problem, as TLS is not going to be set
by caller. However this is not the goal of the
patch and I am not aware if that's even
possible.
Differential Revision: https://reviews.llvm.org/D112197
In a kernel which does not have calls or AGPR usage we can allocate
the whole vector register budget for VGPRs and have no AGPRs as
long as VGPRs stay addressable (i.e. below 256).
Differential Revision: https://reviews.llvm.org/D111764
This patch is a refactor to implement prepend afterwards. Since this changes a lot of files and to conform with guidelines, I will separate this from the implementation of prepend. Related to the discussion in https://reviews.llvm.org/D111414 , so please read it for more context.
Reviewed By: #libc_abi, dblaikie, ldionne
Differential Revision: https://reviews.llvm.org/D111947
Some dwarf loaders in LLVM are hard-coded to only accept 4-byte and 8-byte address sizes. This patch generalizes acceptance into `DWARFContext::isAddressSizeSupported` and provides a common way to generate rejection errors.
The MSP430 target has been given new tests to cover dwarf loading cases that previously failed due to 2-byte addresses.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D111953
There is no need to return a bool and have an SDValue output
parameter. Just return the SDValue and let the caller check if it
is null.
I have another patch to add more callers of these so I thought
I'd clean up the interface first.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112267
By expanding early it allows the shifts to be custom lowered in
LegalizeVectorOps. Then a DAG combine is able to run on them before
LegalizeDAG handles the BUILD_VECTORS for the masks used.
v16Xi8 shift lowering on X86 requires a mask to be applied to a v8i16
shift. The BITREVERSE expansion applied an AND mask before SHL ops and
after SRL ops. This was done to share the same mask constant for both shifts.
It looks like this patch allows DAG combine to remove the AND mask added
after v16i8 SHL by X86 lowering. This maintains the mask sharing that
BITREVERSE was trying to achieve. Prior to this patch it looks like
we kept the mask after the SHL instead which required an extra constant
pool or a PANDN to invert it.
This is dependent on D112248 because RISCV will end up scalarizing the BSWAP
portion of the BITREVERSE expansion if we don't disable BSWAP scalarization in
LegalizeVectorOps first.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112254
It's better to do the ands, shifts, ors in the vector domain than
to scalarize it and do those operations on each element.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112248
G_ICMP is selected to an arithmetic overflow op (ADDS/SUBS/etc) with a dead
destination + a CSINC instruction.
We have a fold which allows us to combine 32-bit adds with G_ICMP.
The problem with G_ICMP is that we model it as always having a 32-bit
destination even though it can be a 64-bit operation. So, we were missing some
opportunities for 64-bit folds.
This patch teaches the fold to recognize 64-bit G_ICMPs + refactors some of
the code surrounding CSINC accordingly.
(Later down the line, I think we should probably change the way we handle G_ICMP
in general.)
Differential Revision: https://reviews.llvm.org/D111088
If a typedef type has __attribute__((btf_decl_tag("str"))) with
bpf target, emit BTF_KIND_DECL_TAG for that type in the BTF.
Differential Revision: https://reviews.llvm.org/D112259
As discussed in D112016, our current requirement of speculatability
for ephemeral is overly strict: What we really care about is that
the instruction will be DCEd once the assume is dropped. For that
it is sufficient that the instruction is side-effect free and not
a terminator.
In particular, this allows non-dereferenceable loads to be ephemeral
values.
Differential Revision: https://reviews.llvm.org/D112179
shuf (bo X, Y), (bo X, W) --> bo (shuf X), (shuf Y, W)
This is motivated by an example in D111800
(although that patch avoids the problem for that particular example).
The pattern is shown in reduced form with:
https://llvm.org/PR52178https://alive2.llvm.org/ce/z/d8zB4D
There is no difference on the PhaseOrdering test from D111800
because the aarch64 cost model says that the shuffle cost is 3 while
the fadd cost is 2.
Differential Revision: https://reviews.llvm.org/D111901
This change restructures the cache used in IPT to point not to the first special instruction, but to the first instruction which *could* be special. That is, the cached reference is always equal to the first special, or comes before it in the block.
This avoids expensive block scans when we are removing special instructions from the beginning of the block. At the moment, this case is not heavily used, though it does trigger in GVN when doing CSE of calls. The main motivation was a change I'm no longer planning to move forward with, but the cache optimization seemed worthwhile as a minor perf win at low cost.
Differential Revision: https://reviews.llvm.org/D111768
- This patch provides the initial implementation for lowering a call on z/OS according to the XPLINK64 calling convention
- A series of changes have been made to SystemZCallingConv.td to account for these additional XPLINK64 changes including adding a new helper function to shadow the stack along with allocation of a register wherever appropriate
- For the cases of copying a f64 to a gr64 and a f128 / 128-bit vector type to a gr64, a `CCBitConvertToType` has been added and has been bitcasted appropriately in the lowering phase
- Support for the ADA register (R5) will be provided in a later patch.
Reviewed By: uweigand
Differential Revision: https://reviews.llvm.org/D111662
(i8 X ^ 128) & (i8 X s>> 7) --> usubsat X, 128
I haven't found a generalization of this identity:
https://alive2.llvm.org/ce/z/_sriEQ
Note: I was actually looking at the first form of the pattern in that link,
but that's part of a long chain of potential missed transforms in codegen
and IR....that I hope ends here!
The predicates for when this is profitable are a bit tricky. This version of
the patch excludes multi-use but includes custom lowering (as opposed to
legal only).
On x86 for example, we have custom lowering for some vector types, and that
uses umax and sub. So to enable that fold, we need add use checks to avoid
regressions. Even with legal-only lowering, we could see code with extra
reg move instructions for extra uses, so that constraint would have to be
eased very carefully to avoid penalties.
Differential Revision: https://reviews.llvm.org/D112085
Vectorization of PHIs and stores very similar, it might be beneficial to
try to revectorize stores (like PHIs) if the total number of stores with
the same/alternate opcode is less than the vector size but number of
stores with the same type is larger than the vector size.
Differential Revision: https://reviews.llvm.org/D109831
When splitting a masked load, `GetDependentSplitDestVTs` is used to get the
MemVTs of the high and low parts. If the masked load is extended, this
may return VTs with different element types which are used to create the
high & low masked load instructions.
This patch changes `GetDependentSplitDestVTs` to ensure we return VTs with
the same element type.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D111996
If clang driver gets 64-bit r6 target triple like `mipsisa64r6` and
additional option forces switching to generation of 32-bit code, it
loses r6 abi and generates 32-bit r2-r5 abi code.
```
$ clang -target mipsisa64r6-linux-gnu -mabi=32
```
This patch fixes the problem.
- Add optional `SubArchType` argument to the `Triple::setArch()` method.
- Implement generation of mips r6 target triples in the
`Triple::getArchName()` method.
Differential Revision: https://reviews.llvm.org/D110514.diff
In order to explore different variants of reassociation current implementation uses "swap in a loop" approach. Unfortunately, the implementation is more complicated than it could be. This is an attempt to streamline the code. New approach is to extract core functionality into a helper function and call it explicitly as many times as required.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D112128
This patch introduces a new function:
AArch64Subtarget::getVScaleForTuning
that returns a value for vscale that can be used for tuning the cost
model when using scalable vectors. The VScaleForTuning option in
AArch64Subtarget is initialised according to the following rules:
1. If the user has specified the CPU to tune for we use that, else
2. If the target CPU was specified we use that, else
3. The tuning is set to "generic".
For CPUs of type "generic" I have assumed that vscale=2.
New tests added here:
Analysis/CostModel/AArch64/sve-gather.ll
Analysis/CostModel/AArch64/sve-scatter.ll
Transforms/LoopVectorize/AArch64/sve-strict-fadd-cost.ll
Differential Revision: https://reviews.llvm.org/D110259
With unoptimized code, we may see lots of stores and spend too much time in mergeTruncStores.
Fixes PR51827.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D111596
This is a small extension of D112095 to avoid another regression
seen with D112085.
In this case, we allow the same conversion from usubsat to ALU
ops if the target supports vpternlog.
That pattern will get converted later in X86DAGToDAGISel::tryVPTERNLOG().
This seems better than putting a magic immediate constant directly in
this code to create the exact vpternlog that we need. It's possible that
there are other special-cases along these lines, so we should try to
keep all of the vpternlog magic in one place.
Differential Revision: https://reviews.llvm.org/D112138
At the moment, rewriteLoopExitValue forgets the current phi node in the
loop that collects phis to rewrite. A few lines after the value is
forgotten, SCEV is used again to analyze incoming values and
potentially expand SCEV expression. This means that another SCEV is
created for PN, before the IR is actually updated in the next loop.
This leads to accessing invalid cached expression in combination with
D71539.
PN should only be changed once the actual incoming exit value is set in
the next loop. Moving invalidation there should ensure that PN is
invalidated in all relevant cases.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D111495
MachineLoop::isLoopInvariant() returns false for all VALU
because of the exec use. Check TII::isIgnorableUse() to
allow hoisting.
That unfortunately results in higher register consumption
since MachineLICM does not adequately estimate pressure.
Therefor I think it shall only be enabled after D107677 even
though it does not depend on it.
Differential Revision: https://reviews.llvm.org/D107859
D106408 was doing this for all targets although it was
reverted due to couple performance regressions on some targets.
The difference for AMDGPU is the ability to rematerialize SOP
instructions with virtual register uses like we already do for VOP.
Differential Revision: https://reviews.llvm.org/D110743
bitcast (inselt (bitcast X), Y, 0) --> or (and X, MaskC), (zext Y)
https://alive2.llvm.org/ce/z/Ux-662
Similar to D111082 / db231ebdb0 :
We want to avoid relatively opaque vector ops on types that are
likely supported by the backend as scalar integers. The bitwise
logic ops are more likely to allow further combining.
We probably want to generalize this to allow a shift too, but
that would oppose instcombine's general rule of not creating
extra instructions, so that's left as a potential follow-up.
Alternatively, we could do that transform in VectorCombine
with the help of the TTI cost model.
This is part of solving:
https://llvm.org/PR52057
As discussed in:
* https://reviews.llvm.org/D94166
* https://lists.llvm.org/pipermail/llvm-dev/2020-September/145031.html
The GlobalIndirectSymbol class lost most of its meaning in
https://reviews.llvm.org/D109792, which disambiguated getBaseObject
(now getAliaseeObject) between GlobalIFunc and everything else.
In addition, as long as GlobalIFunc is not a GlobalObject and
getAliaseeObject returns GlobalObjects, a GlobalAlias whose aliasee
is a GlobalIFunc cannot currently be modeled properly. Creating
aliases for GlobalIFuncs does happen in the wild (e.g. glibc). In addition,
calling getAliaseeObject on a GlobalIFunc will currently return nullptr,
which is undesirable because it should return the object itself for
non-aliases.
This patch refactors the GlobalIFunc class to inherit directly from
GlobalObject, and removes GlobalIndirectSymbol (while inlining the
relevant parts into GlobalAlias and GlobalIFunc). This allows for
calling getAliaseeObject() on a GlobalIFunc to return the GlobalIFunc
itself, making getAliaseeObject() more consistent and enabling
alias-to-ifunc to be properly modeled in the IR.
I exercised some judgement in the API clients of GlobalIndirectSymbol:
some were 'monomorphized' for GlobalAlias and GlobalIFunc, and
some remained shared (with the type adapted to become GlobalValue).
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D108872
Add relaxed. f32x4.min, f32x4.max, f64x2.min, f64x2.max. These are only
exposed as builtins, and require user opt-in.
Differential Revision: https://reviews.llvm.org/D112146
This patch fixes a crash when despeculating ctlz/cttz intrinsics with
scalable-vector types. It is not safe to speculatively get the size of
the vector type in bits in case the vector type is not a fixed-length type. As
it happens this isn't required as vector types are skipped anyway.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112141
Our fallback expansion for CTLZ/CTTZ relies on CTPOP. If CTPOP
isn't legal or custom for a vector type we would scalarize the
CTLZ/CTTZ. This is different than CTPOP itself which would use a
vector expansion.
This patch teaches expandCTLZ/CTTZ to rely on the vector CTPOP
expansion instead of scalarizing. To do this I had to add additional
checks to make sure the operations used by CTPOP expansions are all
supported. Some of the operations were already needed for the CTLZ/CTTZ
expansion.
This is a huge improvement to the RISCV which doesn't have a scalar
ctlz or cttz in the base ISA.
For WebAssembly, I've added Custom lowering to keep the scalarizing
behavior. I've also extended the scalarizing to CTPOP.
Differential Revision: https://reviews.llvm.org/D111919
Here's another performance patch for InstrRefBasedLDV: rather than
processing all variable values in a scope at a time, instead, process one
variable at a time. The benefits are twofold:
* It's easier to reason about one variable at a time in your mind,
* It improves performance, apparently from increased locality.
The downside is that the value-propagation code gets indented one level
further, plus there's some churn in the unit tests.
Differential Revision: https://reviews.llvm.org/D111799
When inserting a scalable subvector into a scalable vector through
the stack, the index to store to needs to be scaled by vscale.
Before this patch, that didn't yet happen, so it would generate the
wrong offset, thus storing a subvector to the incorrect address
and overwriting the wrong lanes.
For some insert:
nxv8f16 insert_subvector(nxv8f16 %vec, nxv2f16 %subvec, i64 2)
The offset was not scaled by vscale:
orr x8, x8, #0x4
st1h { z0.h }, p0, [sp]
st1h { z1.d }, p1, [x8]
ld1h { z0.h }, p0/z, [sp]
And is changed to:
mov x8, sp
st1h { z0.h }, p0, [sp]
st1h { z1.d }, p1, [x8, #1, mul vl]
ld1h { z0.h }, p0/z, [sp]
Differential Revision: https://reviews.llvm.org/D111633
Replace X86ProcFamilyEnum::IntelSLM enum with a TuningUseSLMArithCosts flag instead, matching what we already do for Goldmont.
This just leaves X86ProcFamilyEnum::IntelAtom to replace with general Tuning/Feature flags and we can finally get rid of the old X86ProcFamilyEnum enum.
Differential Revision: https://reviews.llvm.org/D112079
autiasp, autibsp instructions are the counterpart of paciasp/pacibsp instructions
therefore let's emit .cfi_negate_ra_state for these too.
In case of Armv8.3 instruction set the retaa/retbb will do the return and authentication
in one step here we can't emit the . cfi_negate_ra_state because that would be point after
the ret* instruction.
Reviewed By: nickdesaulniers, MaskRay
Differential Revision: https://reviews.llvm.org/D111780
This change implements new DAG nodes TABLE_GET/TABLE_SET, and lowering
methods for load and stores of reference types from IR arrays. These
global LLVM IR arrays represent tables at the Wasm level.
Differential Revision: https://reviews.llvm.org/D111154
Complete the basic integer instruction set and add related predictor in CSKY.td.
And it includes the instruction definition and asm parser support.
Differential Revision: https://reviews.llvm.org/D111701
To guarantee convergence of the algorithm each optimization step should decrease number of instructions when IR is modified. This property is not held in this test case. The problem is that SCEV Expander may do "unexpected" reassociation what results in creation of new min/max chains and introduction of extra instructions. As a result on each step we indefinitely optimize back and forth.
The solution is to restrict SCEV Expander to perform uncontrolled reassociations by means of "Unknown" expressions.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D112060
Add i8x16 relaxed_swizzle instructions. These are only
exposed as builtins, and require user opt-in.
Differential Revision: https://reviews.llvm.org/D112022
Currently, .BTF and .BTF.ext has default alignment of 1.
For example,
$ cat t.c
int foo() { return 0; }
$ clang -target bpf -O2 -c -g t.c
$ llvm-readelf -S t.o
...
Section Headers:
[Nr] Name Type Address Off Size ES Flg Lk Inf Al
...
[ 7] .BTF PROGBITS 0000000000000000 000167 00008b 00 0 0 1
[ 8] .BTF.ext PROGBITS 0000000000000000 0001f2 000050 00 0 0 1
But to have no misaligned data access, .BTF and .BTF.ext
actually requires alignment of 4. Misalignment is not an issue
for architecture like x64/arm64 as it can handle it well. But
some architectures like mips may incur a trap if .BTF/.BTF.ext
is not properly aligned.
This patch explicitly forced .BTF and .BTF.ext alignment to be 4.
For the above example, we will have
[ 7] .BTF PROGBITS 0000000000000000 000168 00008b 00 0 0 4
[ 8] .BTF.ext PROGBITS 0000000000000000 0001f4 000050 00 0 0 4
Differential Revision: https://reviews.llvm.org/D112106
Emit __clangast in custom section instead of named data segment
to find it while iterating sections.
This could be avoided if all data segements (the wasm sense) were
represented as their own sections (in the llvm sense).
This can be resolved by https://github.com/WebAssembly/tool-conventions/issues/138
And the on-disk hashtable in clangast needs to be aligned by 4 bytes,
so add paddings in name length field in custom section header.
The length of clangast section name can be represented in 1 byte
by leb128, and possible maximum pads are 3 bytes, so the section
name length won't be invalid in theory.
Fixes https://bugs.llvm.org/show_bug.cgi?id=35928
Differential Revision: https://reviews.llvm.org/D74531
usubsat X, SMIN --> (X ^ SMIN) & (X s>> BW-1)
This would be a regression with D112085 where we combine to
usubsat more aggressively, so avoid that by matching the
special-case where we are subtracting SMIN (signmask):
https://alive2.llvm.org/ce/z/4_3gBD
Differential Revision: https://reviews.llvm.org/D112095
As seen in PR51869 the ScalarEvolution::isImpliedCond function might
end up spending lots of time when doing the isKnownPredicate checks.
Calling isKnownPredicate for example result in isKnownViaInduction
being called, which might result in isLoopBackedgeGuardedByCond being
called, and then we might get one or more new calls to isImpliedCond.
Even if the scenario described here isn't an infinite loop, using
some random generated C programs as input indicates that those
isKnownPredicate checks quite often returns true. On the other hand,
the third condition that needs to be fulfilled in order to "prove
implications via truncation", i.e. the isImpliedCondBalancedTypes
check, is rarely fulfilled.
I also made some similar experiments to look at how often we would
get the same result when using isKnownViaNonRecursiveReasoning instead
of isKnownPredicate. So far I haven't seen a single case when codegen
is negatively impacted by using isKnownViaNonRecursiveReasoning. On
the other hand, it seems like we get rid of the compile time explosion
seen in PR51869 that way. Hence this patch.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D112080
This is trivial. It was left out of the original review only because we had multiple copies of the same code in review at the same time, and keeping them in sync was easiest if the structure was kept in sync.
This patch duplicates a bit of logic we apply to comparisons encountered during the IV users walk to conditions which feed exit conditions. Why? simplifyAndExtend has a very limited list of users it walks. In particular, in the examples is stops at the zext and never visits the icmp. (Because we can't fold the zext to an addrec yet in SCEV.) Being willing to visit when we haven't simplified regresses multiple tests (seemingly because of less optimal results when computing trip counts).
Note that this can be trivially extended to multiple exiting blocks. I'm leaving that to a future patch (solely to cut down on the number of versions of the same code in review at once.)
Differential Revision: https://reviews.llvm.org/D111896
Using BPI within loop predication is non-trivial because BPI is only
preserved lossily in loop pass manager (one fix exposed by lossy
preservation is up for review at D111448). However, since loop
predication is only used in downstream pipelines, it is hard to keep BPI
from breaking for incomplete state with upstream changes in BPI.
Also, correctly preserving BPI for all loop passes is a non-trivial
undertaking (D110438 does this lossily), while the benefit of using it
in loop predication isn't clear.
In this patch, we rely on profile metadata to get almost similar benefit as
BPI, without actually using the complete heuristics provided by BPI.
This avoids the compile time explosion we tried to fix with D110438 and
also avoids fragile bugs because BPI can be lossy in loop passes
(D111448).
Reviewed-By: asbirlea, apilipenko
Differential Revision: https://reviews.llvm.org/D111668
Summary:
Break out non-functional changes to the print-changed classes that are needed
for reuse with the DotCfg change printer in https://reviews.llvm.org/D87202.
Various changes to the change printers to facilitate reuse with the
upcoming DotCfg change printer. This includes changing several of
the classes and their support classes to being templates. Also,
some template parameter names were simplified to avoid confusion
with planned identifiers in the DotCfg change printer to come. A
virtual function in the class for comparing functions was changed
to a lambda. The virtual function same was replaced with calls to
operator==. The only intentional functional change was to add the exe name
as the first parameter to llvm::sys::ExecuteAndWait
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks)
Differential Revision: https://reviews.llvm.org/D110737
Following on from an earlier patch that introduced support for -mtune
for AArch64 backends, this patch splits out the tuning features
from the processor features. This gives us the ability to enable
architectural feature set A for a given processor with "-mcpu=A"
and define the set of tuning features B with "-mtune=B".
It's quite difficult to write a test that proves we select the
right features according to the tuning attribute because most
of these relate to scheduling. I have created a test here:
CodeGen/AArch64/misched-fusion-addr-tune.ll
that demonstrates the different scheduling choices based upon
the tuning.
Differential Revision: https://reviews.llvm.org/D111551
This patch ensures that we always tune for a given CPU on AArch64
targets when the user specifies the "-mtune=xyz" flag. In the
AArch64Subtarget if the tune flag is unset we use the CPU value
instead.
I've updated the release notes here:
llvm/docs/ReleaseNotes.rst
and added tests here:
clang/test/Driver/aarch64-mtune.c
Differential Revision: https://reviews.llvm.org/D110258
Inspired by D111968, provide a isNegatedPowerOf2() wrapper instead of obfuscating code with (-Value).isPowerOf2() patterns, which I'm sure are likely avenues for typos.....
Differential Revision: https://reviews.llvm.org/D111998
This is purely a performance patch: InstrRefBasedLDV used to use three
DenseMaps to store variable values, two for long term storage and one as a
working set. This patch eliminates the working set, and updates the long
term storage in place, thus avoiding two DenseMap comparisons and two
DenseMap assignments, which can be expensive.
Differential Revision: https://reviews.llvm.org/D111716
When printing names in lldb on windows these names contain the full type information while on linux only the name is contained.
This change introduces a flag in the Microsoft demangler to control if the type information should be included.
With the flag enabled demangled name contains only the qualified name, e.g:
without flag -> with flag
int (*array2d)[10] -> array2d
int (*abc::array2d)[10] -> abc::array2d
const int *x -> x
For globals there is a second inconsistency which is not yet addressed by this change. On linux globals (in global namespace) are prefixed with :: while on windows they are not.
Reviewed By: teemperor, rnk
Differential Revision: https://reviews.llvm.org/D111715
This field gets assigned when the relevant object starts being used; but it
remains uninitialized beforehand. This risks introducing hard-to-detect
bugs if something changes, so zero-initialize the field.
This lifts the global offset table and procedure linkage table builders out of
ELF_x86_64.h and into x86_64.h, renaming them with generic names
x86_64::GOTTableBuilder and x86_64::PLTTableBuilder. MachO_x86_64.cpp is updated
to use these classes instead of the older PerGraphGOTAndStubsBuilder tool.
We would like to move ThinLTO’s battle-tested file caching mechanism to
the LLVM Support library so that we can use it elsewhere in LLVM.
Patch By: noajshu
Differential Revision: https://reviews.llvm.org/D111371
GPR uses argument registers as the first group of registers to allocate.
This patch uses vector argument registers, v8 to v23, as the first group
to allocate.
Differential Revision: https://reviews.llvm.org/D111304
Moves visitEdge into the TableManager derivatives, replacing the fixEdgeKind
methods in those classes. The visitEdge method takes on responsibility for
updating the edge target, as well as its kind.
By default clang emits complete contructors as alias of base constructors if they are the same.
The backend is supposed to emit symbols for the alias, otherwise it causes undefined symbols.
@yaxunl observed that this issue is related to the llvm options `-amdgpu-early-inline-all=true`
and `-amdgpu-function-calls=false`. This issue is resolved by only inlining global values
with internal linkage. The `getCalleeFunction()` in AMDGPUResourceUsageAnalysis also had
to be extended to support aliases to functions. inline-calls.ll was corrected appropriately.
Reviewed By: yaxunl, #amdgpu
Differential Revision: https://reviews.llvm.org/D109707
If we're using an ashr to sign-extend the entire upper 16 bits of the i32 element, then we can replace with a lshr. The sign bit will be correctly shifted for PMADDWD's implicit sign-extension and the upper 16 bits are zero so the upper i16 sext-multiply is guaranteed to be zero.
The lshr also has a better chance of folding with shuffles etc.
RISCVISAInfo::toFeatures needs to allocate strings using
ArgList::MakeArgString, but toFeatures lives in Support and
MakeArgString lives in Option.
toFeature only has one caller, so the simple fix is to have that
caller pass a lamdba that wraps MakeArgString to break the
dependency.
Differential Revision: https://reviews.llvm.org/D112032
The feature tells the backend to allow tags in the upper bits of global
variable addresses. These tags will be ignored by upcoming CPUs with
the Intel LAM feature but may be used in instrumentation passes (e.g.,
HWASan).
This patch implements the feature by using @GOTPCREL relocations instead
of direct references to the locally defined global. Thus the full
tagged address can be loaded by a single instruction:
movq global@GOTPCREL(%rip), %rax
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D111343
When compiling for the RWPI relocation model the debug information is wrong:
* the debug location is described as { DW_OP_addr Var }
instead of { DW_OP_constNu Var DW_OP_bregX 0 DW_OP_plus }
* the relocation type is R_ARM_ABS32 instead of R_ARM_SBREL32
Differential Revision: https://reviews.llvm.org/D111404
Need to follow the order of the reused scalars from the
ReuseShuffleIndices mask rather than rely on the natural order.
Differential Revision: https://reviews.llvm.org/D111898
The goal is to allow grafting an inline tree from Clang or GCC into a new compilation without affecting other functions. For GCC, we're doing this by extracting the inline tree from dwarf information and generating the equivalent remarks.
This allows easier side-by-side asm analysis and a trial way to see if a particular inlining setup provides benefits by itself.
Testing:
ninja check-all
Reviewed By: wenlei, mtrofin
Differential Revision: https://reviews.llvm.org/D110658
We would like to move ThinLTO’s battle-tested file caching mechanism to
the LLVM Support library so that we can use it elsewhere in LLVM.
Patch By: noajshu
Differential Revision: https://reviews.llvm.org/D111371
There are no functionality change.
Fix some comments and rename processAnnotations() to
processDeclAnnotations() to avoid confusion when later
BTF_KIND_TYPE_TAG is introduced (https://reviews.llvm.org/D111199).
Commit 009f3a89d8 ("BPF: remove intrindics @llvm.stacksave()
and @llvm.stackrestore()") implemented IRPeephole pass to remove
llvm.stacksave()/stackrestore() instrinsics.
Buildbot reported a failure:
UNREACHABLE executed at ../lib/IR/LegacyPassManager.cpp:1445!
which is:
llvm_unreachable("Pass modifies its input and doesn't report it");
The code has changed but the implementation didn't return true
for changing. This patch fixed this problem.
This simplifies the return value of addRuntimeCheck from a pair of
instructions to a single `Value *`.
The existing users of addRuntimeChecks were ignoring the first element
of the pair, hence there is not reason to track FirstInst and return
it.
Additionally all users of addRuntimeChecks use the second returned
`Instruction *` just as `Value *`, so there is no need to return an
`Instruction *`. Therefore there is no need to create a redundant
dummy `and X, true` instruction any longer.
Effectively this change should not impact the generated code because the
redundant AND will be folded by later optimizations. But it is easy to
avoid creating it in the first place and it allows more accurately
estimating the cost of the runtime checks.
This function was copied from ARM where register pairs/triples/quads can wrap around the 32 encoding space. So register 31 can pair with register 0. This is not true for RISCV vectors. The spec specifically mentions the possibility of a future encoding that has more than 32 registers.
This patch removes the modulo from the code and directly checks that destination register is in the source register range and not the beginning of the range. Though I don't expect an identity copy will occur.
Reviewed By: frasercrmck
Differential Revision: https://reviews.llvm.org/D111467
Paul Chaignon reported a bpf verifier failure ([1]) due to using
non-ABI register R11. For the test case, llvm11 is okay while
llvm12 and later generates verifier unfriendly code.
The failure is related to variable length array size.
The following mimics the variable length array definition
in the test case:
struct t { char a[20]; };
void foo(void *);
int test() {
const int a = 8;
char tmp[AA + sizeof(struct t) + a];
foo(tmp);
...
}
Paul helped bisect that the following llvm commit is
responsible:
552c6c2328 ("PR44406: Follow behavior of array bound constant
folding in more recent versions of GCC.")
Basically, before the above commit, clang frontend did constant
folding for array size "AA + sizeof(struct t) + a" to be 68,
so used alloca for stack allocation. After the above commit,
clang frontend didn't do constant folding for array size
any more, which results in a VLA and llvm.stacksave/llvm.stackrestore
is generated.
BPF architecture API does not support stack pointer (sp) register.
The LLVM internally used R11 to indicate sp register but it should
not be in the final code. Otherwise, kernel verifier will reject it.
The early patch ([2]) tried to fix the issue in clang frontend.
But the upstream discussion considered frontend fix is really a
hack and the backend should properly undo llvm.stacksave/llvm.stackrestore.
This patch implemented a bpf IR phase to remove these intrinsics
unconditionally. If eventually the alloca can be resolved with
constant size, r11 will not be generated. If alloca cannot be
resolved with constant size, SelectionDag will complain, the same
as without this patch.
[1] https://lore.kernel.org/bpf/20210809151202.GB1012999@Mem/
[2] https://reviews.llvm.org/D107882
Differential Revision: https://reviews.llvm.org/D111897
Record widening decisions for memory operations within the planned recipes and
use the recorded decisions in code-gen rather than querying the cost model.
Differential Revision: https://reviews.llvm.org/D110479
The MIPS ABI requires the thread pointer be accessed via rdhwr $3, $r29.
This is currently represented by (CopyToReg $3, (RDHWR $29)) followed by
a (CopyFromReg $3). However, there is no glue between these, meaning
scheduling can break those apart. In particular, PR51691 is a report
where PseudoSELECT_I was moved to between the CopyToReg and CopyFromReg,
and since its expansion uses branches, it split the def and use of the
physical register between two basic blocks, resulting in the def being
eliminated and the use having no def. It also seems possible that a
similar situation could arise splitting up the CopyToReg from the RDHWR,
causing the RDHWR to use a destination register other than $3, violating
the ABI requirement.
Thus, add glue between all three nodes to ensure they aren't split up
during instruction selection. No regression test is added since any test
would be implictly relying on specific scheduling behaviour, so whilst
it might be testing that glue is preventing reordering today, changes to
scheduling behaviour could result in the test no longer being able to
catch a regression here, as the reordering might no longer happen for
other unrelated reasons.
Fixes PR51691.
Reviewed By: atanasyan, dim
Differential Revision: https://reviews.llvm.org/D111967
Try to widen element type to get a new mask value for a better permutation
sequence, so that we can use NEON shuffle instructions, such as zip1/2,
UZP1/2, TRN1/2, REV, INS, etc.
For example:
shufflevector <4 x i32> %a, <4 x i32> %b, <4 x i32> <i32 6, i32 7, i32 2, i32 3>
is equivalent to:
shufflevector <2 x i64> %a, <2 x i64> %b, <2 x i32> <i32 3, i32 1>
Finally, we can get:
mov v0.d[0], v1.d[1]
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D111619
This is NFC-intended for the callers. Posting in case there are
other potential users that I missed.
I would also use this from VectorCombine in a patch for:
https://llvm.org/PR52178 ( D111901 )
Differential Revision: https://reviews.llvm.org/D111891
Fixes an issue where GEP salvaging did not properly account for GEP
instructions which stepped over array elements of width 0 (effectively a
no-op). This unnecessarily produced long expressions by appending
`... + (x * 0)` and potentially extended the number of SSA values used
in the dbg.value. This also erroneously triggered an assert in the
salvage function that the element width would be strictly positive.
These issues are resolved by simply ignoring these useless operands.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D111809
gcc11 warns that this counter causes a signed/unsigned comaprison when it's
later compared with a SmallVector::difference_type. gcc appears to be
correct, clang does not warn one way or the other.
TargetPassConfig::addPass takes a "bool verifyAfter" argument which lets
you skip machine verification after a particular pass. Unfortunately
this is used in generic code in TargetPassConfig itself to skip
verification after a generic pass, only because some previous target-
specific pass damaged the MIR on that specific target. This is bad
because problems in one target cause lack of verification for all
targets.
This patch replaces that mechanism with a new MachineFunction property
called "FailsVerification" which can be set by (usually target-specific)
passes that are known to introduce problems. Later passes can reset it
again if they are known to clean up the previous problems.
Differential Revision: https://reviews.llvm.org/D111397
Add patterns for i8/i16 local atomic load/store.
Added tests for new patterns.
Copied atomic_[store/load]_local.ll to GlobalISel directory.
Differential Revision: https://reviews.llvm.org/D111869
The process of widening simple vector loads attempts to use a load of a
wider vector type if the original load is sufficiently aligned to avoid
memory faults.
However this optimization is only legal when performed on fixed-length
vector types. For scalable vector types this is invalid (unless vscale
happens to be 1).
This patch does increase the likelihood of compiler crashes (from
`FindMemType` failing to find a suitable type) but this now better
matches how widening non-simple loads, insufficiently-aligned loads, and
scalable-vector stores are handled.
Patches will be introduced later by which loads and stores can be
widened on targets with support for masked or predicated operations.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D111885
This patch is to order the AVX instructions ahead of AVX512 instructions
in the matching table so that the AVX instructions can be matched first.
Thanks Craig and Shengchen for the idea.
Differential Revision: https://reviews.llvm.org/D111538
The change adds divergence predicates for fused logical operations.
The problem with selecting a scalar fused op such as S_NOR_B32 is
that it does not have a VALU counterpart and will be split in
moveToVALU. At the same time it prevents selection of a better
opcode on the VALU side (such as V_OR3_B32) which does not have a
counterpart on SALU side.
XNOR opcodes are left as is and selected as scalar to get advantage
of the SIInstrInfo::lowerScalarXnor() code which can commute
operations to keep one of two opcodes on SALU if possible. See
xnor.ll test for this.
Differential Revision: https://reviews.llvm.org/D111907
Create new virtual register for the definition of new AND instruction and
replace old register by the new one to keep SSA form.
Differential Revision: https://reviews.llvm.org/D109963
We did a experiment and observed dramatic decrease on compilation time which spent on clearing kill flags.
Before:
Number of BasicBlocks:33357
Number of Instructions:162067
Number of Cleared Kill Flags:32869
Time of handling kill flags(ms):1.607509e+05
After:
Number of BasicBlocks:33357
Number of Instructions:162067
Number of Cleared Kill Flags:32869
Time of handling kill flags:3.987371e+03
Reviewed By: MatzeB
Differential Revision: https://reviews.llvm.org/D111688
When peeling a loop, we assume that the latch has a `br` terminator and
that all loop exits are either terminated with an `unreachable` or have
a terminating deoptimize call. So when we peel off the 1st iteration, we
change the IDom of all loop exits to the peeled copy of
`NCD(IDom(Exit), Latch)`. This works now, but if we add logic to support
loops with exits that are followed by a block with an `unreachable` or a
terminating deoptimize call, changing the exit's idom wouldn't be enough
and DT would be broken.
For example, let `Exit1` and `Exit2` are loop exits, and each of them
unconditionally branches to the same `unreachable` terminated block. So
neither of the exits dominates this unreachable block. If we change the
IDoms of the exits to some peeled loop block, we don't update the
dominators of the unreachable block. Currently we just don't get to the
peeling logic, saying that we can't peel such loops.
With this NFC we just insert edges from cloned exiting blocks to their
exits after peeling each iteration (we accumulate the insertion updates
and then after peeling apply the updates to DT).
This patch was a part of D110922.
Patch by Dmitry Makogon!
Differential Revision: https://reviews.llvm.org/D111611
Reviewed By: mkazantsev
Both ports are required for BitTest ops. Update the uops counts + port usage based off the most recent llvm-exegesis captures and what Intel AoM / Agner reports as well.
The multiply() implementation is very slow -- it performs six
multiplications in double the bitwidth, which means that it will
typically work on allocated APInts and bypass fast-path
implementations. Add an additional implementation that doesn't
try to produce anything better than a full range if overflow is
possible. At least for the BasicAA use-case, we really don't care
about more precise modeling of overflow behavior. The current
use of multiply() is fine while the implementation is limited to
a single index, but extending it to the multiple-index case makes
the compile-time impact untenable.
A few more tuples are being queried after D111546. Might be good to model them,
They all require a lot of manual assembly surgery.
The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3
For load we have:
https://godbolt.org/z/9bnKrefcG - for intels `Block RThroughput: =40.0`; for ryzens, `Block RThroughput: =16.0`
So could pick cost of `40`
For store we have:
https://godbolt.org/z/5s3s14dEY - for intels `Block RThroughput: =40.0`; for ryzens, `Block RThroughput: =16.0`
So we could pick cost of `40`.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111945
A few more tuples are being queried after D111546. Might be good to model them,
They all require a lot of manual assembly surgery.
The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3
For load we have:
https://godbolt.org/z/MTaKboejM - for intels `Block RThroughput: =32.0`; for ryzens, `Block RThroughput: <=16.0`
So could pick cost of `32`
For store we have:
https://godbolt.org/z/v7xPj3Wd4 - for intels `Block RThroughput: =32.0`; for ryzens, `Block RThroughput: <=32.0`
So we could pick cost of `32`.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111944
A few more tuples are being queried after D111546. Might be good to model them,
They all require a lot of manual assembly surgery.
The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3
For load we have:
https://godbolt.org/z/11rcvdreP - for intels `Block RThroughput: <=68.0`; for ryzens, `Block RThroughput: <=48.0`
So could pick cost of `68`
For store we have:
https://godbolt.org/z/6aM11fWcP - for intels `Block RThroughput: <=64.0`; for ryzens, `Block RThroughput: <=32.0`
So we could pick cost of `64`.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111943
A few more tuples are being queried after D111546. Might be good to model them,
They all require a lot of manual assembly surgery.
The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3
For load we have:
https://godbolt.org/z/s5b6E6jsP - for intels `Block RThroughput: <=32.0`; for ryzens, `Block RThroughput: <=24.0`
So could pick cost of `32`
For store we have:
https://godbolt.org/z/efh99d93b - for intels `Block RThroughput: <=48.0`; for ryzens, `Block RThroughput: <=32.0`
So we could pick cost of `48`.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111942
A few more tuples are being queried after D111546. Might be good to model them,
They all require a lot of manual assembly surgery.
The only sched models that for cpu's that support avx2
but not avx512 are: haswell, broadwell, skylake, zen1-3
For load we have:
https://godbolt.org/z/YTeT9M7fW - for intels `Block RThroughput: <=212.0`; for ryzens, `Block RThroughput: <=64.0`
So could pick cost of `212`
For store we have:
https://godbolt.org/z/vc954KEGP - for intels `Block RThroughput: <=90.0`; for ryzens, `Block RThroughput: <=24.0`
So we could pick cost of `90`.
I'm directly using the shuffling asm the llc produced,
without any manual fixups that may be needed
to ensure sequential execution.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111940
SVE has predicated literal forms of some instructions for specific
literals, which currently are generated correctly when using ACLE
but not when those instructions are generated directly.
This adds the patterns to generate those instructions when
generating from standard LLVM IR instructions.
Differential Revision: https://reviews.llvm.org/D99074
How many place you need to modify when implementing a new extension for RISC-V?
At least 7 places as I know:
- Add new SubtargetFeature at RISCV.td
- -march parser in RISCV.cpp
- RISCVTargetInfo::initFeatureMap@RISCV.cpp for handling feature vector.
- RISCVTargetInfo::getTargetDefines@RISCV.cpp for pre-define marco.
- Arch string parser for ELF attribute in RISCVAsmParser.cpp
- ELF attribute emittion in RISCVAsmParser.cpp, and make sure it's in
canonical order...
- ELF attribute emittion in RISCVTargetStreamer.cpp, and again, must in
canonical order...
And now, this patch provide an unified infrastructure for handling (almost)
everything of RISC-V arch string.
After this patch, you only need to update 2 places for implement an extension
for RISC-V:
- Add new SubtargetFeature at RISCV.td, hmmm, it's hard to avoid.
- Add new entry to RISCVSupportedExtension@RISCVISAInfo.cpp or
SupportedExperimentalExtensions@RISCVISAInfo.cpp .
Most codes are come from existing -march parser, but with few new feature/bug
fixes:
- Accept version for -march, e.g. -march=rv32i2p0.
- Reject version info with `p` but without minor version number like `rv32i2p`.
Differential Revision: https://reviews.llvm.org/D105168
This patch detects the absolute value pattern on the RHS of a
subtract. If we find it we swap the CMOV true/false values and
replace the subtract with an ADD.
There may be a more generic way to do this, but I'm not sure.
Targets that don't have legal or custom ISD::ABS use a generic
expand in DAG combiner already when it sees (neg (abs(x))). I
haven't checked what happens if the neg is a more general subtract.
Fixes PR50991 for X86.
Reviewed By: RKSimon, spatel
Differential Revision: https://reviews.llvm.org/D111858
The sdiv used to check for overflow can itself overflow if the
LHS is signed min and the RHS is -1. The code tried to account for
this by also checking the commuted version. However, for 1-bit
values, signed min and -1 are the same value, so both divisions
overflow. As such, the overflow for -1 * -1 was not detected
(which results in -1 rather than 1 for 1-bit values). Fix this by
explicitly checking for this case instead.
Noticed while adding exhaustive test coverage for smul_ov(),
which is also part of this commit.
These cases use the same codegen as AVX2 (pshuflw/pshufd) for the sub-128bit vector deinterleaving, and unpcklqdq for v2i64.
It's going to take a while to add full interleaved cost coverage, but since these are the same for SSE2 -> AVX2 it should be an easy win.
Fixes PR47437
Differential Revision: https://reviews.llvm.org/D111938
Also sort ERROR_BAD_NETPATH correctly.
Compared with the similar error code mapping in
libcxx/src/filesystem/operations.cpp, I'm leaving out
mappings for ERROR_NOT_SAME_DEVICE and ERROR_OPERATION_ABORTED.
They map nicely to std::errc::cross_device_link and
std::errc::operation_canceled, but those aren't available in
llvm::errc, as they aren't available across all platforms.
Also, the libcxx version maps ERROR_INVALID_NAME to
no_such_file_or_directory instead of invalid_argument.
Differential Revision: https://reviews.llvm.org/D111874
Add support for demangling Rust v0 symbols to LLVM symbolizer by reusing
nonMicrosoftDemangle which supports both Itanium and Rust mangling.
Reviewed By: dblaikie, jhenderson
Part of https://reviews.llvm.org/D110664
Introduce a new demangling function that supports symbols using Itanium
mangling and Rust v0 mangling, and is expected in the near future to
include support for D mangling as well.
Unlike llvm::demangle, the function does not accept extra underscore
decoration. The callers generally know exactly when symbols should
include the extra decoration and so they should be responsible for
stripping it.
Functionally the only intended change is to allow demangling Rust
symbols with an extra underscore decoration through llvm::demangle,
which matches the existing behaviour for Itanium symbols.
Reviewed By: dblaikie, jhenderson
Part of https://reviews.llvm.org/D110664
And another attempt to start untangling this ball of threads around gather.
There's `TTI::prefersVectorizedAddressing()`hoop, which confusingly defaults to `true`,
which tells LV to try to vectorize the addresses that lead to loads,
but X86 generally can not deal with vectors of addresses,
the only instructions that support that are GATHER/SCATTER,
but even those aren't available until AVX2, and aren't really usable until AVX512.
This specializes the hook for X86, to return true only if we have AVX512 or AVX2 w/ fast gather.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111546
For the common case where the shift amount is constant (a single
element range) we can easily compute a precise range (up to
unsigned envelope), so do that.
This removes an over-specified fold. The more general transform
was added with:
727e642e97
There's a difference on an existing test that shows a potentially
unnecessary use limit on an icmp fold.
That fold is in InstCombinerImpl::foldICmpSubConstant(), and IIRC
there was some back-and-forth on it and similar folds because they
could cause analysis/passes (SCEV, LSR?) to miss optimizations.
Differential Revision: https://reviews.llvm.org/D111410
(iN X s>> (N-1)) & Y --> (X < 0) ? Y : 0
https://alive2.llvm.org/ce/z/qeYhdz
I was looking at a missing abs() transform and found my way to this
generalization of an existing fold that was added with D67799.
As discussed in that review, we want to make sure codegen handles
this difference well, and for all of the targets/types that I
spot-checked, it looks good.
I am leaving the existing fold in place in this commit because
it covers a potentially missing icmp fold, but I plan to remove
that as a follow-up commit as suggested during review.
Differential Revision: https://reviews.llvm.org/D111410
This patch adds a pass option to only run transforms that scalarize
vector operations and do not create new vector instructions.
When running VectorCombine early in the pipeline introducing new vector
operations can have negative effects, like blocking loop or SLP
vectorization. To avoid regressions, restrict the early VectorCombine
run (when using -enable-matrix) to only perform scalarization and not
introduce new vector operations.
This is done as option to the pass directly, which is then set when
adding the pass to the pipeline. This is done for the new pass manager
only.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D111800
By default clang emits complete contructors as alias of base constructors if they are the same.
The backend is supposed to emit symbols for the alias, otherwise it causes undefined symbols.
@yaxunl observed that this issue is related to the llvm options `-amdgpu-early-inline-all=true`
and `-amdgpu-function-calls=false`. This issue is resolved by only inlining global values
with internal linkage. The `getCalleeFunction()` in AMDGPUResourceUsageAnalysis also had
to be extended to support aliases to functions. inline-calls.ll was corrected appropriately.
Reviewed By: yaxunl, #amdgpu
Differential Revision: https://reviews.llvm.org/D109707
- When a redundant MBB is being erased from MDT, check whether its
single successor is dominiated by it. If yes, update that successor's
idom before erasing MBB; otherwise, it implies MBB is a leaf node and
could be erased directly.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D111831
After D80369, the retainedTypes in CU's should not have any subprograms
so we should not handle that case when emitting debug info.
Differential Revision: https://reviews.llvm.org/D111593
Fixes: https://bugs.llvm.org/show_bug.cgi?id=51841
This patch places an arbitrary limit on the size of DIExpressions that
we will produce via salvaging, for performance reasons. This helps to
fix a performance issue observed in the bug above, in which debug values
would be salvaged hundreds of times, producing expressions with over
1000 elements and causing the compiler to hang. Limiting the size of
debug values that we will produce to 128 largely fixes this issue.
Reviewed By: dblaikie, jmorse
Differential Revision: https://reviews.llvm.org/D110332
The isU24() and isI24() calls numBits to make its decision. This change
replaces them with the internal numBits call so that we can use its
result for the > 32 bit width cases.
Differential Revision: https://reviews.llvm.org/D111864
This changes fixes a case in which the highest set bit of the original
result is at bit 31 and sign-extending the mul24 for it would make the
result negative.
Differential Revision: https://reviews.llvm.org/D111823
Add lshr (sext i1 X to iN), C --> select (X, -1 >> C, 0) case. This expands
C == N-1 case to arbitrary C.
Fixes PR52078.
Reviewed By: spatel, RKSimon, lebedev.ri
Differential Revision: https://reviews.llvm.org/D111330
Similar to D111236, this improves the lowering of vector fptosi.sat and
fptoui.sat, using legal converts and further saturating from there with
min/max. f64 are excluded for the moment due to producing worse code in
places compared to the unrolling.
Differential Revision: https://reviews.llvm.org/D111787
Improve the lowering of scalar fptosi.sat and fptoui.sat for saturating
widths smaller than legal types by using the fact that the legal type
will saturate under aarch64, and saturating the result further using
min/max.
Differential Revision: https://reviews.llvm.org/D111236
The MOVCC peephole eliminates a MOVCC by making one of its inputs a
conditional instruction, but when doing this it should be using both
inputs of the MOVCC to decide on the register class to use as
otherwise we can get an error when using -verify-machineinstrs.
Differential Revision: https://reviews.llvm.org/D111714
Use SH1ADD/SH2ADD/SH3ADD along with LUI+ADDI to compose int32*3,
int32*5 and int32*9.
Reviewed By: craig.topper, luismarques
Differential Revision: https://reviews.llvm.org/D111484
This patch teaches SCEV two implication rules:
x <u y && y >=s 0 --> x <s y,
x <s y && y <s 0 --> x <u y.
And all equivalents with signs/parts swapped.
Differential Revision: https://reviews.llvm.org/D110517
Reviewed By: nikic
Current implementations of DFS in SCEV check unique-visited of traversed
values on pop, and not on push. As result, the same value may be pushed
multiple times just to be thrown away when popped. These operations are
meaningless and only waste time and increase memory footprint of the
worklist.
This patch reworks the DFS strategy to check uniqueness before push.
Should be NFC.
Differential Revision: https://reviews.llvm.org/D111774
Reviewed By: nikic, reames
Fix a bug when getInlineCost incorrectly returns a
cost/threshold pair instead of an explicit never inline.
Reviewed By: mtrofin
Differential Revision: https://reviews.llvm.org/D111687
PseudoProbeUpdatePass is used to distribute sample counts among dulplicated probes. It doesn't make sense for it to run without a sample profile. The pass takes 1% of the build time.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D111847
Need to check that either Idx is UndefMaskElem and value is UndefValue
or Idx is valid and value is the same as the scalar value in the node.
Differential Revision: https://reviews.llvm.org/D111802
While i've modelled most of the relevant tuples for AVX2,
that only covered fully-interleaved groups.
By definition, interleaving load of stride N means:
load N*VF elements, and shuffle them into N VF-sized vectors,
with 0'th vector containing elements `[0, VF)*stride + 0`,
and 1'th vector containing elements `[0, VF)*stride + 1`.
Example: https://godbolt.org/z/df561Me5E (i64 stride 4 vf 2 => cost 6)
Now, not fully interleaved load, is when not all of these vectors is demanded.
So at worst, we could just pretend that everything is demanded,
and discard the non-demanded vectors. What this means is that the cost
for not-fully-interleaved group should be not greater than the cost
for the same fully-interleaved group, but perhaps somewhat less.
Examples:
https://godbolt.org/z/a78dK5Geq (i64 stride 4 (indices 012u) vf 2 => cost 4)
https://godbolt.org/z/G91ceo8dM (i64 stride 4 (indices 01uu) vf 2 => cost 2)
https://godbolt.org/z/5joYob9rx (i64 stride 4 (indices 0uuu) vf 2 => cost 1)
As we have established over the course of last ~70 patches, (wow)
`BaseT::getInterleavedMemoryOpCos()` is absolutely bogus,
it is usually almost an order of magnitude overestimation,
so i would claim that we should at least use the hardcoded costs
of fully interleaved load groups.
We could go further and adjust them e.g. by the number of demanded indices,
but then i'm somewhat fearful of underestimating the cost.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111174
Rather than checking for loop nest preheaders upfront in IVUsers,
move this requirement into isSafeToExpand() from SCEVExpander.
Historically, LSR did not check whether SCEVs are safe to expand
and fully relied on IVUsers to validate this. Later, support for
non-expandable SCEVs was added via rigid formulas.
Checking this in isSafeToExpand() makes it more obvious what
exactly this check is guarding against, and avoids the awkward
loop nest scan.
This is a followup to https://reviews.llvm.org/D111493#3055286.
Differential Revision: https://reviews.llvm.org/D111681
CMOVGE reads SF and OF. CMOVNS only reads SF. This matches with
other recent changes to use a single flag where possible. It also
matches gcc codegen.
I believe this technically changes whether the conditioanl move happens
on INT_MIN, but for INT_MIN both registers are the same so it doesn't
matter.
Differential Revision: https://reviews.llvm.org/D111826
Currently, DecomposeGEP() bails out on the whole decomposition if
it encounters a scalable GEP type anywhere. However, it is fine to
still analyze other GEPs that we look through before hitting the
scalable GEP. This does mean that the decomposed GEP base is no
longer required to be the same as the underlying object. However,
I don't believe this property is necessary for correctness anymore.
This allows us to compute slightly more precise aliasing results
for GEP chains containing scalable vectors, though my primary
interest here is simplifying the code.
Differential Revision: https://reviews.llvm.org/D110511
This a NFC refactor patch to merge the AVX2 interleaved cost handling back into the getInterleavedMemoryOpCost base method - while getInterleavedMemoryOpCostAVX512 uses instruction and patterns very specific to AVX512+, much of the costs analysis for AVX2 can be reused for all SSE targets.
This is the first step towards improving SSE and AVX1 costs that will reuse the relevant AVX2 costs by splitting some of the tables - for instance AVX1 has very similar costs for most vXi64/vXf64 interleave patterns and many sub-128bit vector costs are the same all the way down to SSE2 (or at least SSSE3).
Differential Revision: https://reviews.llvm.org/D111822
I have some upcoming refactoring for SSE/AVX1 interleaving cost support, and the diff is a lot nicer if the (unaltered) AVX512 implementation isn't stuck between getInterleavedMemoryOpCost and getInterleavedMemoryOpCostAVX2
The initial MemoryAccess *Current assignment is never used, and all other uses are initialized/used within the worklist loop (and not across multiple iterations) - so move the variable internal to the loop.
Fixes scan-build unused assignment warning.
Currently the fadd optimizations in InstSimplify don't know how to do this
NoSignedZeros "X + 0.0 ==> X" fold when using the constrained intrinsics.
This adds the support.
This review is derived from D106362 with some improvements from D107285
and is a follow-on to D111085.
Differential Revision: https://reviews.llvm.org/D111450
I've removed the Zbs W instructions that are not part of the frozen spec.
References to B as an extension name have been removed. Tests are updated or split accordingly.
Reviewed By: luismarques
Differential Revision: https://reviews.llvm.org/D110669
This patch add a TableManager which reponsible for fixing edges that need entries to reference the target symbol and constructing such entries.
In the past, the PerGraphGOTAndPLTStubsBuilder pass was used to build GOT and PLT entry, and the PerGraphTLSInfoEntryBuilder pass was used to build TLSInfo entry. By generalizing the behavior of building entry, I added a TableManager which could be reused when built GOT, PLT and TLSInfo entries.
If this patch makes sense and can be accepted, I will apply the TableManager to other targets(MachO_x86_64, MachO_arm64, ELF_riscv), and delete the file PerGraphGOTAndPLTStubsBuilder.h
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D110383
This patch is very similar to D110173 / a3936a6c19, but for variable
values rather than machine values. This is for the second instr-ref
problem, calculating the correct variable value on entry to each block.
The previous lattice based implementation was broken; we now use LLVMs
existing PHI placement utilities to work out where values need to merge,
then eliminate un-necessary ones through value propagation.
Most of the deletions here happen in vlocJoin: it was trying to pick a
location for PHIs to happen in, badly, leading to an infinite loop in the
MIR test added, where it would repeatedly switch between register
locations. The new approach is simpler: either PHIs can be eliminated, or
they can't, and the location of the value is a different problem.
Various bits and pieces move to the header so that they can be tested in
the unit tests. The DbgValue class grows a "VPHI" kind to represent
variable value PHIS that haven't been eliminated yet.
Differential Revision: https://reviews.llvm.org/D110630
These registers are used as operands for instructions that expect an
integer register, so they should be added to Int32Regs or Int64Regs
register classes. Otherwise the machine verifier emits an error for
the following LIT tests when LLVM_ENABLE_MACHINE_VERIFIER=1
environment variable is set:
*** Bad machine code: Illegal physical register for instruction ***
- function: kernel_func
- basic block: %bb.0 entry (0x55c8903d5438)
- instruction: %3:int64regs = LEA_ADDRi64 $vrframelocal, 0
- operand 1: $vrframelocal
$vrframelocal is not a Int64Regs register.
CodeGen/NVPTX/call-with-alloca-buffer.ll
CodeGen/NVPTX/disable-opt.ll
CodeGen/NVPTX/lower-alloca.ll
CodeGen/NVPTX/lower-args.ll
CodeGen/NVPTX/param-align.ll
CodeGen/NVPTX/reg-types.ll
DebugInfo/NVPTX/dbg-declare-alloca.ll
DebugInfo/NVPTX/dbg-value-const-byref.ll
Differential Revision: https://reviews.llvm.org/D110164
The patch attempts to optimize a sequence of SIMD loads from the same
base pointer:
%0 = gep float*, float* base, i32 4
%1 = bitcast float* %0 to <4 x float>*
%2 = load <4 x float>, <4 x float>* %1
...
%n1 = gep float*, float* base, i32 N
%n2 = bitcast float* %n1 to <4 x float>*
%n3 = load <4 x float>, <4 x float>* %n2
For AArch64 the compiler generates a sequence of LDR Qt, [Xn, #16].
However, 32-bit NEON VLD1/VST1 lack the [Wn, #imm] addressing mode, so
the address is computed before every ld/st instruction:
add r2, r0, #32
add r0, r0, #16
vld1.32 {d18, d19}, [r2]
vld1.32 {d22, d23}, [r0]
This can be improved by computing address for the first load, and then
using a post-indexed form of VLD1/VST1 to load the rest:
add r0, r0, #16
vld1.32 {d18, d19}, [r0]!
vld1.32 {d22, d23}, [r0]
In order to do that, the patch adds more patterns to DAGCombine:
- (load (add ptr inc1)) and (add ptr inc2) are now folded if inc1
and inc2 are constants.
- (or ptr inc) is now recognized as a pointer increment if ptr is
sufficiently aligned.
In addition to that, we now search for all possible base updates and
then pick the best one.
Differential Revision: https://reviews.llvm.org/D108988
Without SSE41 sext/zext instructions the extensions will be split, meaning that the MUL->PMADDWD fold will split the sext_i32(x) into zext_i32(sext_i16(x))
Some functions get opted out of instruction referencing if they're being
compiled with no optimisations, however the LiveDebugValues pass picks one
implementation and then sticks with it through the rest of compilation.
This leads to a segfault if we encounter a function that doesn't use
instr-ref (because it's optnone, for example), but we've already decided
to use InstrRefBasedLDV which expects to be passed a DomTree.
Solution: keep both implementations around in the pass, and pick whichever
one is appropriate to the current function.
This patch fixes the bug that consisted of treating variable / immediate
length mem operations (such as memcpy, memset, ...) differently. The variable
length case needs to have the length minus 1 passed due to the use of EXRL
target instructions. However, the DAGCombiner can convert a register length
argument into a constant one, and whenever that happened one byte too little
would end up being performed.
This is also a refactorization by reducing the number of opcodes and variants
involved. For any opcode (variable or constant length), only the length minus
one is passed on to the ISD node. The rest of the logic is now instead
handled during isel pseudo expansion.
Review: Ulrich Weigand
Differential Revision: https://reviews.llvm.org/D111729
Replace check with
if ((ExitIfTrue && CI->isZero()) || (!ExitIfTrue && CI->isOne()))
with equivalent and simpler version
if (ExitIfTrue == CI->isZero())
Opitimize immediate materialisation in the following way if profitable:
1. Use BCLRI for upper 32 bits if the lower 32 bits are negative int32.
2. Use BSETI for upper 32 bits if the lower 32 bits are positive int32.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D111508
The 24-bit mul intrinsics yields the low-order 32 bits. We should only
do the transformation if the operands are known to be not wider than 24
bits and the result is known to be not wider than 32 bits.
Differential Revision: https://reviews.llvm.org/D111523
SimpleRemoteEPC notionally allowed subclasses to override the
createMemoryManager and createMemoryAccess methods to use custom objects, but
could not actually be subclassed in practice (The construction process in
SimpleRemoteEPC::Create could not be re-used).
Instead of subclassing, this commit adds a SimpleRemoteEPC::Setup class that
can be used by clients to set up the memory manager and memory access members.
A default-constructed Setup object results in no change from previous behavior
(EPCGeneric* memory manager and memory access objects used by default).
If the parameter had been annotated as nonnull because of the null
check, we want to remove the attribute, since it may no longer apply and
could result in miscompiles if left. Similarly, we also want to remove
undef-implying attributes, since they may not apply anymore either.
Fixes PR52110.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D111515
The tests that exercise the 'release' mode, where the model is AOT-ed,
check the output has certain properties, to validate that, indeed, a
different policy from the default one was exercised. For determinism, we
can't reliably check that output for an arbitrary learned policy, since
it could be that policy happens to mimic the default one in that
particular case.
This patch adds a requirement that those tests run only when the model
is autogenerated (e.g. on build bots).
Differential Revision: https://reviews.llvm.org/D111747
This extends the foldOpIntoPhi code used when visiting a freeze user of a phi to allow any non-undef/poison operand as opposed to only non-undef/poison constants. This lets us hoist a freeze in the increment of an IV into the preheader in many cases.
Differential Revision: https://reviews.llvm.org/D111744
After 8fc7a907b9, this loop does
the same as a plain `std::replace`.
Also clarify the comment about what this function does.
Differential Revision: https://reviews.llvm.org/D111730
`X86TTIImpl::getGSScalarCost()` has (at least) two issues:
* it naively computes the cost of sequence of `insertelement`/`extractelement`.
If we are operating not on the XMM (but YMM/ZMM),
this widely overestimates the cost of subvector insertions/extractions.
* Gather/scatter takes a vector of pointers, and scalarization results in us performing
scalar memory operation for each of these pointers, but we never account for the cost
of extracting these pointers out of the vector of pointers.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111222
Even if there are no interesting functions, the SCCP solver would still run
before bailing. Now bail earlier, avoid running the solver for nothing.
Differential Revision: https://reviews.llvm.org/D111645
NFC. This check does not verify any functional property since size 8
was added. Remove it for simplicity.
Reviewed By: rampitec
Differential Revision: https://reviews.llvm.org/D111737
Change-Id: Ifd7cbd324a137f939d8dc04acb8fbd54c9527a42
This PR implements the save of the XPLINK callee-saved registers
on z/OS.
Reviewed By: uweigand, Kai
Differential Revision: https://reviews.llvm.org/D111653
This is a follow on for D111675 which implements the gep case. I'd originally left it out because I was hoping to actually implement the inrange todo, but after a bit of staring at the code, decided to leave it as is since it doesn't effect this use case (i.e. instcombine requires the op to freeze to be an instruction).
Differential Revision: https://reviews.llvm.org/D111691
This has a couple of benefits:
1. It can sometimes fix clusters that got broken apart when the register
allocator inserted a copy.
2. Post-RA scheduling does not have to worry about increasing register
pressure, which in some cases gives it more freedom to reorder
instructions.
Testing on a collection of 10,000 graphics shaders compiled for gfx1010
showed:
- The average length of each run of one or more load instructions
increased by about 1%.
- The number of runs of two or more load instructions increased by
about 4%.
Differential Revision: https://reviews.llvm.org/D111646
In D110173 we start using the existing LLVM IDF calculator to place PHIs as
we reconstruct an SSA form of machine-code program. Sadly that's slower
than the old (but broken) way, this patch attempts to recover some of that
performance.
The key observation: every time we def a register, we also have to def it's
register units. If we def'd $rax, in the current implementation we
independently calculate PHI locations for {al, ah, ax, eax, hax, rax}, and
they will all have the same PHI positions. Instead of doing that, we can
calculate the PHI positions for {al, ah} and place PHIs for any aliasing
registers in the same positions. Any def of a super-register has to def
the unit, and vice versa, so this is sound. It cuts down the SSA placement
we need to do significantly.
This doesn't work for stack slots, or registers we only ever read, so place
PHIs normally for those. LiveDebugValues choses to ignore writes to SP at
calls, and now have to ignore writes to SP register units too.
Differential Revision: https://reviews.llvm.org/D111627
This is NFC-intended for scalar code. There are still unnecessary
m_ConstantInt restrictions in surrounding code, so this is not a
complete fix.
This prevents regressions seen with a planned follow-on to D111410.
Old versions of gcc want template specialisations to happen within the
namespace where the template lives; this is still present in gcc 5.1, which
we officially support, so it has to be worked around.
InstrRefBasedLDV used to try and determine which values are in which
registers using a lattice approach; however this is hard to understand, and
broken in various ways. This patch replaces that approach with a standard
SSA approach using existing LLVM utilities. PHIs are placed at dominance
frontiers; value propagation then eliminates un-necessary PHIs.
This patch also adds a bunch of unit tests that should cover many of the
weirder forms of control flow.
Differential Revision: https://reviews.llvm.org/D110173
This patch adds patterns to match the following with INC/DEC:
- @llvm.aarch64.sve.cnt[b|h|w|d] intrinsics + ADD/SUB
- vscale + ADD/SUB
For some implementations of SVE, INC/DEC VL is not as cheap as ADD/SUB and
so this behaviour is guarded by the "use-scalar-inc-vl" feature flag, which for SVE
is off by default. There are no known issues with SVE2, so this feature is
enabled by default when targeting SVE2.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D111441
This makes Wasm EH work with dynamic linking. So far we were only able
to handle destructors, which do not use any tags or LSDA info.
1. This uses `TargetExternalSymbol` for `GCC_except_tableN` symbols,
which points to the address of per-function LSDA info. It is more
convenient to use than `MCSymbol` because it can take additional
target flags.
2. When lowering `wasm_lsda` intrinsic, if PIC is enabled, make the
symbol relative to `__memory_base` and generate the `add` node. If
PIC is disabled, continue to use the absolute address.
3. Make tag symbols (`__cpp_exception` and `__c_longjmp`) undefined in
the backend, because it is hard to make it work with dynamic
linking's loading order. Instead, we make all tag symbols undefined
in the LLVM backend and import it from JS.
4. Add support for undefined tags to the linker.
Companion patches:
- https://github.com/WebAssembly/binaryen/pull/4223
- https://github.com/emscripten-core/emscripten/pull/15266
Reviewed By: sbc100
Differential Revision: https://reviews.llvm.org/D111388
Negative deltas for LDRLiteral19 have their high bits set. If these bits aren't
masked out then they will overwrite other instruction bits, leading to a bogus
encoding.
This long-standing relocation bug was exposed by e50aea58d5, "[JITLink][ORC]
Major JITLinkMemoryManager refactor.", which caused memory layouts to be
reordered, which in turn lead to a previously unseen negative delta. (Unseen
because LDRLiteral19s were only created in JITLink passes where they always
pointed at segments that were layed-out-after in the old layout).
No testcase yet: Our existing regression test infrastructure is good at checking
that operand bits are correct, but provides no easy way to test for bad opcode
bits. I'll have a think about the right way to approach this.
https://llvm.org/PR52153
The mips-specific includes have been unnecessary ever since the
__clear_cache() builtin replaced cacheflush().
Differential Revision: https://reviews.llvm.org/D111486
The newly introduced API for checking whether poison comes solely from flags which can be dropped was out of sync. This was noticed by a reviewer post commit.
For the moment, disable the floating point flags. In a follow up change, I plan to add support in dropPoisonGeneratingFlags, but that deserves to be a change of it's own.
Do the following optimization for immediate materialisation:
1. For values in range 0xffffffff 7fffffff ~ 0xffffffff 00000000, first
generate the lower 32-bit with Val|0x80000000 (which is expected be an
int32), then emit (BCLRI r, 31).
2. For values in range 0x80000000 ~ 0xffffffff, first generate the lower
32-bit with Val&~0x80000000 (which is expected to be an int32), then
emit (BSETI r, 31).
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D111532
GCC 9.1 removed Intel MPX support. Linux kernel removed MPX in 2019.
glibc 2.35 will remove MPX.
Our support is limited: we support assembling of bndmov but not bnd.
Just remove it.
Reviewed By: pengfei, skan
Differential Revision: https://reviews.llvm.org/D111517
If we have an instruction which produces poison only when flags are specified on the instruction, then we know that freezing the operands and dropping flags is equivalent to freezing the result. If we know those flags don't result in any undefined behavior being executed, then there's no point in preserving the flags as we gain no knowledge by having them.
This patch extends the existing propagation logic which sinks freeze to single potential non-poison operands to allow dropping of flags when we know the freeze is the sole use of the instruction with poison flags.
The main value is that we tend to sink freezes towards the phi in IV cycles where the incoming value to the phi is the freeze of an IV increment. This will in turn (in a future patch), let us fold the freeze through the phi into the loop preheader. Motivated by eliminating need for CanonicalizeFreezeInLoops for the clearly profitable cases from onephi.ll test case in the test directory.
Differential Revision: https://reviews.llvm.org/D111675
On AIX, the system assembler does not support the extended mnemonics
dcbtt and dcbtstt. This patch stops them from being emitted on
AIX and emits the base mnemonics instead, dcbt X, X, 16 and
dcbtstt X, X, 16 respectively.
Differential revision: https://reviews.llvm.org/D111258
f341161689 added a task dispatcher for async handlers, but didn't add a
TaskDispatcher::shutdown call to SelfExecutorProcessControl or SimpleRemoteEPC.
This patch adds the missing call, which ensures that we don't destroy the
dispatcher while tasks are still running.
This should fix the use-after-free crash seen in
https://lab.llvm.org/buildbot/#/builders/5/builds/13063
This patch fixes another crash revealed by PR51614:
when *deciding* to vectorize with masked interleave groups, check if the access
is reverse (which is currently not supported).
Differential Revision: https://reviews.llvm.org/D108900
If another inlining session came after a ModuleInlinerWrapperPass, the
advisor alanysis would still be cached, but its Result would be cleared.
We need to clear both.
This addresses PR52118
Differential Revision: https://reviews.llvm.org/D111586
The new pass walks kernel's pointer arguments, then loads from them.
If a loaded value is a pointer and loaded pointer is unmodified in
the kernel before the load, then promote loaded pointer to global.
Then recursively continue.
Differential Revision: https://reviews.llvm.org/D111464
This may not be obvious, but Alive2 agrees:
https://alive2.llvm.org/ce/z/Ld9qNT
If the mul has "nsw", then -1 * INT_MIN is poison, so the
negate can also have "nsw" because 0 - INT_MIN is poison.
If the mul has "nuw", then that means the "OtherOp" can only
be 0 or 1 (anything else multiplied by 0xfff... would wrap).
So the replacement negate must be "nsw" because it is either
"0-0" or "0-1".
This is another regression noticed with a planned follow-up
to D111410.
As noted in https://github.com/halide/Halide/pull/6302,
we hilariously fail to match PAVG if we even as much
as look at it the wrong way.
In this particular case, the problem stems from the fact that
`PAVG` root (def) is a `trunc`, and leafs (uses) are `zext`'s,
and InstCombine really loves to get rid of both of these,
for example replace them with a bit mask. So we may not have
said `zext`.
Instead of checking for that + type match,
i think we should rely on the actual active type,
as per the knownbits.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D111571
This patch continues unblocking optimizations that are blocked by pseudo probe instrumentation.
Not exactly like DbgIntrinsics, PseudoProbe intrinsic has other attributes (such as mayread, maywrite, mayhaveSideEffect) that can block optimizations. The issues fixed are:
- Flipped default param of getFirstNonPHIOrDbg API to skip pseudo probes
- Unblocked CSE by avoiding pseudo probe from clobbering memory SSA
- Unblocked induction variable simpliciation
- Allow empty loop deletion by treating probe intrinsic isDroppable
- Some refactoring.
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D110847
These "dump" methods call into MachineOperand::dump, which doesn't exist
with NDEBUG, thus we croak. Disable LiveDebugValues dump methods when
NDEBUG is turned on to avoid this.
With the -early-live-intervals command line flag,
TwoAddressInstructionPass::runOnMachineFunction would call
MachineFunction::verify before returning to check the live intervals.
But there was not much benefit to doing this since -verify-machineinstrs
and LLVM_ENABLE_EXPENSIVE_CHECKS provide a more general way of
scheduling machine verification after every pass.
Also it caused problems on targets like Lanai which are marked as "not
machine verifier clean", since verification would fail for known
target-specific problems which are nothing to do with LiveIntervals.
Differential Revision: https://reviews.llvm.org/D111618
This has a couple of benefits:
1. It can sometimes fix clusters that got broken apart when the register
allocator inserted a copy.
2. Post-RA scheduling does not have to worry about increasing register
pressure, which in some cases gives it more freedom to reorder
instructions.
Testing on a collection of 10,000 graphics shaders compiled for gfx1010
showed:
- The average length of each run of one or more load instructions
increased by about 1%.
- The number of runs of two or more load instructions increased by
about 4%.
This patch shifts the InstrRefBasedLDV class declaration to a header.
Partially because it's already massive, but mostly so that I can start
writing some unit tests for it. This patch also adds the boilerplate for
said unit tests.
Differential Revision: https://reviews.llvm.org/D110165
collectLoopScalars collects pointer induction updates in ScalarPtrs, assuming
that the instruction will be scalar after vectorization. This may crash later
in VPReplicateRecipe::execute() if there there is another user of the instruction
other than the Phi node which needs to be widened.
This changes collectLoopScalars so that if there are any other users of
Update other than a Phi node, it is not added to ScalarPtrs.
Reviewed By: david-arm, fhahn
Differential Revision: https://reviews.llvm.org/D111294
This is a follow up of D110529 that disallowed constexprs. That change
introduced a regression as this also disallowed constexprs that are function
pointers, which is actually one of the motivating use cases that we do want to
support.
Differential Revision: https://reviews.llvm.org/D111567
This patch adds a new cost heuristic that allows peeling a single
iteration off read-only loops, if the loop contains a load that
1. is feeding an exit condition,
2. dominates the latch,
3. is not already known to be dereferenceable,
4. and has a loop invariant address.
If all non-latch exits are terminated with unreachable, such loads
in the loop are guaranteed to be dereferenceable after peeling,
enabling hoisting/CSE'ing them.
This enables vectorization of loops with certain runtime-checks, like
multiple calls to `std::vector::at` if the vector is passed as pointer.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D108114
Rename vfredsum and vfwredsum to vfredusum and vfwredusum. Add aliases for vfredsum and vfwredsum.
Reviewed By: luismarques, HsiangKai, khchen, frasercrmck, kito-cheng, craig.topper
Differential Revision: https://reviews.llvm.org/D105690
Adds explicit narrowing casts to JITLinkMemoryManager.cpp.
Honors -slab-address option in llvm-jitlink.cpp, which was accidentally
dropped in the refactor.
This effectively reverts commit 6641d29b70.
Per discussion in https://reviews.llvm.org/D111199,
the existing btf_tag attribute will be renamed to
btf_decl_tag. This patch updated BTF backend to
use btf_decl_tag attribute name and also
renamed BTF_KIND_TAG to BTF_KIND_DECL_TAG.
Differential Revision: https://reviews.llvm.org/D111592
All those frame indices which are dead after sgpr spill should be removed from
the function frame. Othewise, there is a side effect such as re-mapping of free
frame index ids by the later pass(es) like "stack slot coloring" which in turn
could mess-up with the book keeping of "frame index to VGPR lane".
Reviewed By: cdevadas
Differential Revision: https://reviews.llvm.org/D111150
Per discussion in https://reviews.llvm.org/D111199,
the existing btf_tag attribute will be renamed to
btf_decl_tag. This patch mostly updated the Bitcode and
DebugInfo test cases with new attribute name.
Differential Revision: https://reviews.llvm.org/D111591
This commit substantially refactors the JITLinkMemoryManager API to: (1) add
asynchronous versions of key operations, (2) give memory manager implementations
full control over link graph address layout, (3) enable more efficient tracking
of allocated memory, and (4) support "allocation actions" and finalize-lifetime
memory.
Together these changes provide a more usable API, and enable more powerful and
efficient memory manager implementations.
To support these changes the JITLinkMemoryManager::Allocation inner class has
been split into two new classes: InFlightAllocation, and FinalizedAllocation.
The allocate method returns an InFlightAllocation that tracks memory (both
working and executor memory) prior to finalization. The finalize method returns
a FinalizedAllocation object, and the InFlightAllocation is discarded. Breaking
Allocation into InFlightAllocation and FinalizedAllocation allows
InFlightAllocation subclassses to be written more naturally, and FinalizedAlloc
to be implemented and used efficiently (see (3) below).
In addition to the memory manager changes this commit also introduces a new
MemProt type to represent memory protections (MemProt replaces use of
sys::Memory::ProtectionFlags in JITLink), and a new MemDeallocPolicy type that
can be used to indicate when a section should be deallocated (see (4) below).
Plugin/pass writers who were using sys::Memory::ProtectionFlags will have to
switch to MemProt -- this should be straightworward. Clients with out-of-tree
memory managers will need to update their implementations. Clients using
in-tree memory managers should mostly be able to ignore it.
Major features:
(1) More asynchrony:
The allocate and deallocate methods are now asynchronous by default, with
synchronous convenience wrappers supplied. The asynchronous versions allow
clients (including JITLink) to request and deallocate memory without blocking.
(2) Improved control over graph address layout:
Instead of a SegmentRequestMap, JITLinkMemoryManager::allocate now takes a
reference to the LinkGraph to be allocated. The memory manager is responsible
for calculating the memory requirements for the graph, and laying out the graph
(setting working and executor memory addresses) within the allocated memory.
This gives memory managers full control over JIT'd memory layout. For clients
that don't need or want this degree of control the new "BasicLayout" utility can
be used to get a segment-based view of the graph, similar to the one provided by
SegmentRequestMap. Once segment addresses are assigned the BasicLayout::apply
method can be used to automatically lay out the graph.
(3) Efficient tracking of allocated memory.
The FinalizedAlloc type is a wrapper for an ExecutorAddr and requires only
64-bits to store in the controller. The meaning of the address held by the
FinalizedAlloc is left up to the memory manager implementation, but the
FinalizedAlloc type enforces a requirement that deallocate be called on any
non-default values prior to destruction. The deallocate method takes a
vector<FinalizedAlloc>, allowing for bulk deallocation of many allocations in a
single call.
Memory manager implementations will typically store the address of some
allocation metadata in the executor in the FinalizedAlloc, as holding this
metadata in the executor is often cheaper and may allow for clean deallocation
even in failure cases where the connection with the controller is lost.
(4) Support for "allocation actions" and finalize-lifetime memory.
Allocation actions are pairs (finalize_act, deallocate_act) of JITTargetAddress
triples (fn, arg_buffer_addr, arg_buffer_size), that can be attached to a
finalize request. At finalization time, after memory protections have been
applied, each of the "finalize_act" elements will be called in order (skipping
any elements whose fn value is zero) as
((char*(*)(const char *, size_t))fn)((const char *)arg_buffer_addr,
(size_t)arg_buffer_size);
At deallocation time the deallocate elements will be run in reverse order (again
skipping any elements where fn is zero).
The returned char * should be null to indicate success, or a non-null
heap-allocated string error message to indicate failure.
These actions allow finalization and deallocation to be extended to include
operations like registering and deregistering eh-frames, TLS sections,
initializer and deinitializers, and language metadata sections. Previously these
operations required separate callWrapper invocations. Compared to callWrapper
invocations, actions require no extra IPC/RPC, reducing costs and eliminating
a potential source of errors.
Finalize lifetime memory can be used to support finalize actions: Sections with
finalize lifetime should be destroyed by memory managers immediately after
finalization actions have been run. Finalize memory can be used to support
finalize actions (e.g. with extra-metadata, or synthesized finalize actions)
without incurring permanent memory overhead.
This patch contains following enhancements to SrcRegMap and DstRegMap:
1 In findOnlyInterestingUse not only check if the Reg is two address usage,
but also check after commutation can it be two address usage.
2 If a physical register is clobbered, remove SrcRegMap entries that are
mapped to it.
3 In processTiedPairs, when create a new COPY instruction, add a SrcRegMap
entry only when the COPY instruction is coalescable. (The COPY src is
killed)
With these enhancements isProfitableToCommute can do better commute decision,
and finally more register copies are removed.
Differential Revision: https://reviews.llvm.org/D108731
LoopSimplifyCFG does not need MSSA, but should preserve it if it's available.
This is a legacy PM change, aimed to denoise the test changes in D109958.
Differential Revision: https://reviews.llvm.org/D111578
In SimpleRemoteEPC, calls to from callWrapperAsync to sendMessage may fail.
The handlers may or may not be sent failure messages by handleDisconnect,
depending on when that method is run. This patch adds a check for an un-failed
handler, and if it finds one sends it a failure message.
IVUsers currently makes sure that all loops dominating a user are
in loop simplify form, because SCEVExpander needs a preheader to
insert into. However, loop simplify form requires much more than
that. In particular, it requires dedicated exits, which means that
exits need to be found and walked. For large functions with many
nested loops, this can result in pathological compile-time explosion.
Fix this by only checking the property we're actually interested in,
which is incidentally cheap to check.
Differential Revision: https://reviews.llvm.org/D111493
This shouldn't be called for non-neon targets at the moment in either
case, but it is good to be expliit about the CombineBaseUpdate being a
NEON function, not expecting to be run under MVE.
The CFG being changed and the overall call graph are not related, we can introduce/remove calls without changing the CFG.
Resolves one of the issues in PR51946.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D111275
There may be some other patterns like this or a generalization,
but this is an example that I noticed would definitely regress
with a planned follow-up to D111410.
https://alive2.llvm.org/ce/z/GVpQDb
PHI elimination updates LiveVariables info as described here:
// We only need to update the LiveVariables kill of SrcReg if this was the
// last PHI use of SrcReg to be lowered on this CFG edge and it is not live
// out of the predecessor. We can also ignore undef sources.
Unfortunately if the last use also happened to be an undef use then it
would fail to update the LiveVariables at all. Fix this by not counting
undef uses in the VRegPHIUse map.
Thanks to Mikael Holmén for the test case!
Differential Revision: https://reviews.llvm.org/D111552
At the moment, a VPValue is created for the backedge-taken count, which
is used by some recipes. To make it easier to identify the operands of
recipes using the backedge-taken count, print it at the beginning of the
VPlan if it is used.
Reviewed By: a.elovikov
Differential Revision: https://reviews.llvm.org/D111298
On the controller-side, handle `Hangup` messages from the executor. The executor passed `Error::success()` or a failure message as payload.
Hangups cause an immediate disconnect of the transport layer. The disconnect function may be called later again and so implementations should be prepared. `FDSimpleRemoteEPCTransport::disconnect()` already has a flag to check that:
cd1bd95d87/llvm/lib/ExecutionEngine/Orc/Shared/SimpleRemoteEPCUtils.cpp (L112)
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D111527
This reverts commits f9aba9a5af and
035217ff51.
As explained in the original commit message, this didn't have the
intended effect of improving the common LLDB use case, but still
provided a marginal improvement for the places where LLDB creates a
scoped time with a string literal.
The reason for the revert is that this change pulls in the os/signpost.h
header in Signposts.h. The former transitively includes loader.h, which
contains a series of macro defines that conflict with MachO.h. There are
ways to work around that, but Adrian and I concluded that none of them
are worth the trade-off in complicating Signposts.h even further.
These instructions should allow src0 to be a literal with the same
value as the mandatory other literal. Enable it by introducing an
operand that defers adding its value to the MI when decoding till
the mandatory literal is parsed.
Reviewed By: dp, foad
Differential Revision: https://reviews.llvm.org/D111067
Change-Id: I22b0ae0d35bad17b6f976808e48bffe9a6af70b7
As a brief reminder, an "exit count" is the number of times the backedge executes before some event. It can be zero if we exit before the backedge is reached. A "trip count" is the number of times the loop header is entered if we branch into the loop. In general, TC = BTC + 1 and thus a zero trip count is ill defined
There is a cornercases which we don't handle well. Let's assume i8 for our examples to keep things simple. If BTC = 255, then the correct trip count is 256. However, 256 is not representable in i8.
In theory, code which needs to reason about trip counts is responsible for checking for this cornercase, and either bailing out, or handling it correctly. Historically, we don't have a great track record about actually doing so.
When reviewing D109676, I found myself asking a basic question. Was there any good reason to preserve the current wrap-to-zero behavior when converting from backedge taken counts to trip counts? After reviewing existing code, I could not find a single case which appears to correctly and precisely handle the overflow case.
This patch changes the default behavior to extend instead of wrap. That is, if the result might be 256, we return a value of i9 type to ensure we interpret the count correctly. I did leave the legacy behavior as an option since a) loop-flatten stops triggering if I extend due to weirdly specific pattern matching I didn't understand and b) we could reasonably use the mode if we'd externally established a lack of overflow.
I want to emphasize that this change is *not* NFC. There are two call sites (one in ScalarEvolution.cpp, one in LoopCacheAnalysis.cpp) which are switched to the extend semantics. The former appears imprecise (but correct) for a constant 255 BTC. The later appears incorrect, though I don't have a test case.
Differential Revision: https://reviews.llvm.org/D110587
armv9-a, armv9.1-a and armv9.2-a can be targeted using the -march option
both in ARM and AArch64.
- Armv9-A maps to Armv8.5-A.
- Armv9.1-A maps to Armv8.6-A.
- Armv9.2-A maps to Armv8.7-A.
- The SVE2 extension is enabled by default on these architectures.
- The cryptographic extensions are disabled by default on these
architectures.
The Armv9-A architecture is described in the Arm® Architecture Reference
Manual Supplement Armv9, for Armv9-A architecture profile
(https://developer.arm.com/documentation/ddi0608/latest).
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D109517
Adds LLVMOrcCreateStaticLibrarySearchGeneratorForPath and
LLVMOrcCreateDynamicLibrarySearchGeneratorForPath functions to create generators
for static and dynamic libraries.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D108535
https://bugs.llvm.org/show_bug.cgi?id=27506https://bugs.llvm.org/show_bug.cgi?id=31652https://bugs.llvm.org/show_bug.cgi?id=51043
Problems with SimpleLoopUnswitch cause the bug reports above.
```
while (...) {
if (C) { A }
else { B }
}
Into:
C' = freeze(C)
if (C') {
while (...) { A }
} else {
while (...) { B }
}
```
This problem can be solved by adding a freeze on hoisted branches(above transform) and has been solved by D29015.
However, D29015 is now reverted by performance regression(2b5a897651)
It is not the first time that an added freeze has caused performance regression.
SimplifyCFG also had a problem with UB caused by branching-on-undef, which was solved by adding freeze to the branching condition. (D104569)
Performance regression occurred in D104569, and patches such as D105344 and D105392 were written to minimize it.
This patch will correct the SimpleLoopUnswitch as D104569 handles the SimplyCFG while minimizing performance loss by introducing patches like D105344 and D105392(This patch was rebased with the author's permission)
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D106041
The Object library currently has three identical functions that translate a
Twine into a parser error. Until recently these functions have coexisted
peacefully, but since D110320 Clang with enabled modules is now diagnosing that
we have several definitions of `createError` in Object.
This patch just merges them all and puts them into Object's `Error.h` where the
error code for `parse_failed` is also defined which seems cleaner and unbreaks
the bots.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D111541
The select(pshufb,pshufb) -> or(pshufb,pshufb) fold uses getConstVector to create the refreshed pshufb masks, which treats all negative indices as undef.
PR52122 shows that if we were selecting an element that the PSHUFB has set to zero we must set it back to 0x80 when we recreate the PSHUFB mask and not just leave it as SM_SentinelZero
The lowering for EXTRACT_SUBVECTOR should not be called during type
legalization, only as part of lowering, hence return SDValue() when
called on illegal types.
This also adds missing tests for extracting fixed types from illegal
scalable types.
Differential Revision: https://reviews.llvm.org/D111412
AAPCS requires i1 argument to be zero-extended to 8-bits by the
caller. Emit a new AArch64ISD::ASSERT_ZEXT_BOOL hint (or AssertZExt
for GlobalISel) to enable some optimization opportunities. In
particular, when the argument is forwarded to the callee, we can avoid
zero-extension and use it as-is.
Differential Revision: https://reviews.llvm.org/D107160
This patch adds further support for vectorisation of loops that involve
selecting an integer value based on a previous comparison. Consider the
following C++ loop:
int r = a;
for (int i = 0; i < n; i++) {
if (src[i] > 3) {
r = b;
}
src[i] += 2;
}
We should be able to vectorise this loop because all we are doing is
selecting between two states - 'a' and 'b' - both of which are loop
invariant. This just involves building a vector of values that contain
either 'a' or 'b', where the final reduced value will be 'b' if any lane
contains 'b'.
The IR generated by clang typically looks like this:
%phi = phi i32 [ %a, %entry ], [ %phi.update, %for.body ]
...
%pred = icmp ugt i32 %val, i32 3
%phi.update = select i1 %pred, i32 %b, i32 %phi
We already detect min/max patterns, which also involve a select + cmp.
However, with the min/max patterns we are selecting loaded values (and
hence loop variant) in the loop. In addition we only support certain
cmp predicates. This patch adds a new pattern matching function
(isSelectCmpPattern) and new RecurKind enums - SelectICmp & SelectFCmp.
We only support selecting values that are integer and loop invariant,
however we can support any kind of compare - integer or float.
Tests have been added here:
Transforms/LoopVectorize/AArch64/sve-select-cmp.ll
Transforms/LoopVectorize/select-cmp-predicated.ll
Transforms/LoopVectorize/select-cmp.ll
Differential Revision: https://reviews.llvm.org/D108136
We were using the type of the loop back edge count to represent the
store size. This failed for small loop counts (e.g. in the added test,
the loop count was an i2).
Use the index type instead.
Fixes PR52104.
Differential Revision: https://reviews.llvm.org/D111401
The callWrapperAsync and callSPSWrapperAsync methods take a handler object
that is run on the return value of the call when it is ready. The new RunPolicy
parameters allow clients to control how these handlers are run. If no policy is
specified then the handler will be packaged as a GenericNamedTask and dispatched
using the ExecutorProcessControl's TaskDispatch member. Callers can use the
ExecutorProcessControl::RunInPlace policy to cause the handler to be run
directly instead, which may be preferrable for simple handlers, or they can
write their own policy object (e.g. to dispatch as some other kind of Task,
rather than GenericNamedTask).
Summary: This patch improves the error message context of the
XCOFF interfaces by providing more details.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D110320
f341161689 introduced a dependence (for builds with LLVM_ENABLE_THREADS) on
pthreads. This commit updates the CMakeLists.txt file to include a LINK_LIBS
entry for pthreads.
ExecutorProcessControl objects will now have a TaskDispatcher member which
should be used to dispatch work (in particular, handling incoming packets in
the implementation of remote EPC implementations like SimpleRemoteEPC).
The GenericNamedTask template can be used to wrap function objects that are
callable as 'void()' (along with an optional name to describe the task).
The makeGenericNamedTask functions can be used to create GenericNamedTask
instances without having to name the function object type.
In a future patch ExecutionSession will be updated to use the
ExecutorProcessControl's dispatcher, instead of its DispatchTaskFunction.
The callee address is now the first parameter and the 'SendResult' function
the second. This change improves consistentency with the non-async functions
where the callee is the first address and the return value the second.
Transformation from malloc+memset to calloc is always correct and in many situations
it brings significant observable benefits in terms of execution speed and memory consumption [1][2].
Unfortunately there are cases when producing calloc cause performance drops [3].
As discussed here: https://reviews.llvm.org/D103009 it's possible to differentiate between those 2 scenarios.
If optimizer is able to prove that after malloc call it's _very_ likely to reach memset branch then after
calloc emission we shouldn't observe any performance hits. Therefore finding "null pointer check" pattern
before memset basic block sounds like good justification for performing transformation.
Also that method was already suggested by GCC folks [4]. Main reason for change is that for now
to be safe we check for post dominance relation which is way too conservative approach making transformation
"almost" disabled in practice. This patch tends to enable transformation again but with extra care.
[1] https://stackoverflow.com/questions/2688466/why-mallocmemset-is-slower-than-calloc
[2] https://vorpus.org/blog/why-does-calloc-exist/
[3] http://smalldatum.blogspot.com/2017/11/a-new-optimization-in-gcc-5x-and-mysql.html
[4] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83022
Differential Revision: https://reviews.llvm.org/D110021
The test diffs show that we have better analysis/folds for 'add'
(although we should at least have the simplifications
independently, so we don't have the one-use restriction).
This is related to solving regressions that would appear in
transforms related to D111410, and that is part of a series
of enhancements that may eventually helpi solve PR34047.
https://alive2.llvm.org/ce/z/3tB9KG
define i1 @src(i8 %x, i8 %C, i8 %C2) {
%sub = sub nuw i8 %C2, %x
%r = icmp slt i8 %sub, %C
ret i1 %r
}
define i1 @tgt(i8 %x, i8 %C, i8 %C2) {
%Cnot = xor i8 %C, -1
%C2not = xor i8 %C2, -1
%add = add nuw i8 %x, %C2not
%r = icmp sgt i8 %add, %Cnot
ret i1 %r
}
This adds the `--dump-blockinfo` flag to `llvm-bcanalyzer`, allowing a sufficiently motivated user to dump (parts of) the `BLOCKINFO_BLOCK` block. The default behavior is unchanged, and `--dump-blockinfo` only takes effect in the same context as other flags that control dump behavior (i.e., requires that `--dump` is also passed).
Reviewed By: tejohnson
Differential Revision: https://reviews.llvm.org/D107536
There were 2 related but over-specified folds for:
C1 - X == C
One allowed multi-use but was limited to equal constants.
The other allowed different constants but disallowed multi-use.
This combines the 2 folds into a more general match.
The test diffs show the multi-use cases that were falling
through the cracks.
https://alive2.llvm.org/ce/z/4_hEt2
define i1 @src(i8 %x, i8 %subC, i8 %C) {
%s = sub i8 %subC, %x
%r = icmp eq i8 %s, %C
ret i1 %r
}
define i1 @tgt(i8 %x, i8 %subC, i8 %C) {
%newC = sub i8 %subC, %C
%isneg = icmp eq i8 %x, %newC
ret i1 %isneg
}
We would like to start pushing -mcpu=generic towards enabling the set of
features that improves performance for some CPUs, without hurting any
others. A blend of the performance options hopefully beneficial to all
CPUs. The largest part of that is enabling in-order scheduling using the
Cortex-A55 schedule model. This is similar to the Arm backend change
from eecb353d0e which made -mcpu=generic perform in-order scheduling
using the cortex-a8 schedule model.
The idea is that in-order cpu's require the most help in instruction
scheduling, whereas out-of-order cpus can for the most part out-of-order
schedule around different codegen. Our benchmarking suggests that
hypothesis holds. When running on an in-order core this improved
performance by 3.8% geomean on a set of DSP workloads, 2% geomean on
some other embedded benchmark and between 1% and 1.8% on a set of
singlecore and multicore workloads, all running on a Cortex-A55 cluster.
On an out-of-order cpu the results are a lot more noisy but show flat
performance or an improvement. On the set of DSP and embedded
benchmarks, run on a Cortex-A78 there was a very noisy 1% speed
improvement. Using the most detailed results I could find, SPEC2006 runs
on a Neoverse N1 show a small increase in instruction count (+0.127%),
but a decrease in cycle counts (-0.155%, on average). The instruction
count is very low noise, the cycle count is more noisy with a 0.15%
decrease not being significant. SPEC2k17 shows a small decrease (-0.2%)
in instruction count leading to a -0.296% decrease in cycle count. These
results are within noise margins but tend to show a small improvement in
general.
When specifying an Apple target, clang will set "-target-cpu apple-a7"
on the command line, so should not be affected by this change when
running from clang. This also doesn't enable more runtime unrolling like
-mcpu=cortex-a55 does, only changing the schedule used.
A lot of existing tests have updated. This is a summary of the important
differences:
- Most changes are the same instructions in a different order.
- Sometimes this leads to very minor inefficiencies, such as requiring
an extra mov to move variables into r0/v0 for the return value of a test
function.
- misched-fusion.ll was no longer fusing the pairs of instructions it
should, as per D110561. I've changed the schedule used in the test
for now.
- neon-mla-mls.ll now uses "mul; sub" as opposed to "neg; mla" due to
the different latencies. This seems fine to me.
- Some SVE tests do not always remove movprfx where they did before due
to different register allocation giving different destructive forms.
- The tests argument-blocks-array-of-struct.ll and arm64-windows-calls.ll
produce two LDR where they previously produced an LDP due to
store-pair-suppress kicking in.
- arm64-ldp.ll and arm64-neon-copy.ll are missing pre/postinc on LPD.
- Some tests such as arm64-neon-mul-div.ll and
ragreedy-local-interval-cost.ll have more, less or just different
spilling.
- In aarch64_generated_funcs.ll.generated.expected one part of the
function is no longer outlined. Interestingly if I switch this to use
any other scheduled even less is outlined.
Some of these are expected to happen, such as differences in outlining
or register spilling. There will be places where these result in worse
codegen, places where they are better, with the SPEC instruction counts
suggesting it is not a decrease overall, on average.
Differential Revision: https://reviews.llvm.org/D110830
There is a bug reported at https://bugs.llvm.org/show_bug.cgi?id=48938
After looking through the glibc, I found the `atexit(f)` is the same as `__cxa_atexit(f, NULL, NULL)`. In orc runtime, we identify different JITDylib by their dso_handle value, so that a NULL dso_handle is invalid. So in this patch, I added a `PlatformJDDSOHandle` to ELFNixRuntimeState, and functions which are registered by atexit will be registered at PlatformJD.
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D111413
The current code checks whether the vector's element type is a valid structure element type, rather than a valid vector element type. The two have separate implementations and but only accept very slightly different sets of types, which is probably why this wasn't caught before.
Differential Revision: https://reviews.llvm.org/D109655
566690b0 uses size information in float semantics, but PPCDoubleDouble
left them empty.
As follow-up, we can consider remove PPCDoubleDoubleLegacy and fill
other fields in the future.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D111398
llvm.is.constant* intrinsics are evaluated to 0 or 1 integral values.
A common use case for llvm.is.constant comes from the higher level
__builtin_constant_p. A common usage pattern of __builtin_constant_p in
the Linux kernel is:
void foo (int bar) {
if (__builtin_constant_p(bar)) {
// lots of code that will fold away to a constant.
} else {
// a little bit of code, usually a libcall.
}
}
A minor issue in InlineCost calculations is when `bar` is _not_ Constant
and still will not be after inlining, we don't discount the true branch
and the inline cost of `foo` ends up being the cost of both branches
together, rather than just the false branch.
This leads to code like the above where inlining will not help prove bar
Constant, but it still would be beneficial to inline foo, because the
"true" branch is irrelevant from a cost perspective.
For example, IPSCCP can sink a passed constant argument to foo:
const int x = 42;
void bar (void) { foo(x); }
This improves our inlining decisions, and fixes a few head scratching
cases were the disassembly shows a relatively small `foo` not inlined
into a lone caller.
We could further improve this modeling by tracking whether the argument
to llvm.is.constant* is a parameter of the function, and if inlining
would allow that parameter to become Constant. This idea is noted in a
FIXME comment.
Link: https://github.com/ClangBuiltLinux/linux/issues/1302
Reviewed By: kazu
Differential Revision: https://reviews.llvm.org/D111272
This moves the registry higher in the LLVM library dependency stack.
Every client of the target registry needs to link against MC anyway to
actually use the target, so we might as well move this out of Support.
This allows us to ensure that Support doesn't have includes from MC/*.
Differential Revision: https://reviews.llvm.org/D111454
PR45875 notes an instance where exception handling crashes on aarch64-fuchsia
where SCS is enabled by default. The underlying issue seems to be that within libunwind,
various _Unwind_* functions, the x18 register is not updated if a function is marked
with nounwind. This removes the check for nounwind and emits the CFI instruction that updates x18.
Differential Revision: https://reviews.llvm.org/D79822
If a loop is flattened, the inner loop is removed and the LPM
should be informed of this fact, so it can invalidate associated
analyses. To support this, we relax an assertion in LPMUpdater to
allow invalidating non-top-level loops when running in LoopNestMode,
as the pass does not know how exactly it will get scheduled.
Differential Revision: https://reviews.llvm.org/D111350
This reverts commit dfd74db981.
SimpleRemoteEPC should share dispatch with the ExecutionSession, rather than
having two different dispatch systems on the controller side.
SimpleRemoteEPCServer::Dispatch doesn't need to be shared.
Renames SimpleRemoteEPCServer::Dispatcher to SimpleRemoteEPCDispatcher and
moves it into OrcShared. SimpleRemoteEPCServer::ThreadDispatcher is similarly
moved and renamed to DynamicThreadPoolSimpleRemoteEPCDispatcher.
This will allow these classes to be reused by SimpleRemoteEPC on the controller
side of the connection.
We only need to invalidate if the instruction being removed is the cached "first special instruction". If the instruction is before that one, it can't (by assumption) be special. If it is after that one, it wasn't the first.
The RISCV target doesn't define a "generic" cpu, only "generic-rv32" and
"generic-rv64". Define sys::getHostCPUName for RISC-V that returns the
correct cpu for the host.
Reviewed By: craig.topper, MaskRay
Differential Revision: https://reviews.llvm.org/D105274
This factors out utilities for scanning a bounded block of instructions since we have this code repeated in a bunch of places. The change to InlineFunction isn't strictly NFC as the limit mechanism there didn't handle debug instructions correctly.
This reverts commit 3e8d2008f7.
The code removed in this commit is actually required for extracting
fixed types from illegal scalable types, hence this commit causes
assertion failures in such extracts.
For PS shaders we can use the input SPI_PS_INPUT_ENA and SPI_PS_INPUT_ADDR
registers
Calculate the number of VGPR registers used as input VGPRs based on these
registers rather than the arguments passed in (this conservatively always
allocates the maximum).
Differential Revision: https://reviews.llvm.org/D101633
Change-Id: Idf7c060cbbd5f7e3300102c55ecee3c07f209de6
Removed obsolete DT verification that should not be there because the
strategy of DT updates has changed.
Differential Revision: https://reviews.llvm.org/D110922
This was using MachineFunction::createExternalSymbolName() before, which seems
reasonable, but in fact this is freed before the asm emitter which tries to access
the function name string. Switching it to use the string returned by the attribute
seems to fix the problem.
In order to not generate an unnecessary G_CTLZ, I extended the constant folder
in the CSEMIRBuilder to handle G_CTLZ. I also added some extra handing of
vector constants too. It seems we don't have any support for doing constant
folding of vector constants, so the tests show some other useless G_SUB
instructions too.
Differential Revision: https://reviews.llvm.org/D111036
At this point it looks like a B extension will never exist. Instead
Zba, Zbb, Zbc, and Zbs are individual extensions being ratified
together as a package. Unknown at this time when or if the other
Zb* extensions will be ratified.
This patch removes references to the B extension. I've updated and
split tests accordingly.
This has been split from D110669 to make review a little easier.
Differential Revision: https://reviews.llvm.org/D111338
Added support for peeling loops with "deoptimizing" exits -
such exits that it or any of its children (or any of their
children, etc) either has a @llvm.experimental.deoptimize call
prior to the terminating return instruction of this basic block
or is terminated with unreachable. All blocks in the the
sequence must have a single successor, maybe except for the last
one.
Previously we only checked the exit block for being deoptimizing.
Now we check if the last reachable block from the exit is deoptimizing.
Patch by Dmitry Makogon!
Differential Revision: https://reviews.llvm.org/D110922
Reviewed By: mkazantsev
This patch adds two flags to be supported for the new runtime. The flags
are `-fopenmp-assume-threads-oversubscription` and
-fopenmp-assume-teams-oversubscription`. These add global values that
can be checked by the work sharing runtime functions to make better
judgements about how to distribute work between the threads.
Reviewed By: jdoerfert
Differential Revision: https://reviews.llvm.org/D111348
The shift libcalls have a shift amount parameter of MVT::i32, but
sometimes ExpandIntRes_Shift may be called with a node whose
second operand is a type that is larger than that. This leads to
an ABI mismatch, and for example causes a spurious zeroing of
a register in RV32 for 64-bit shifts. Note that at present regular
shift intstructions already have their shift amount operand adapted
at SelectionDAGBuilder::visitShift time, and funnelled shifts bypass that.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D110508
Using uselistorders is fairly niche, it shouldn't be on by default and mostly just clutters the output.
Reviewed By: jamieschmeiser
Differential Revision: https://reviews.llvm.org/D111282
This change fixes a bug where the compiler generates a prologue_end
for line 0 locs. That is because line 0 is not associated with any
source location, so there should not be a prolgoue_end at a location
that doesn't correspond to a source location.
There were some LLVM tests that were explicitly checking for line 0
prologue_end's as well since I believe that to be incorrect, I had to
change those tests as well.
Patch by Shubham Rastogi!
Differential Revision: https://reviews.llvm.org/D110740
Updating the MachineDominatorTree is easy since SILowerControlFlow only
splits and removes basic blocks. This should save a bit of compile time
because previously we would recompute the dominator tree from scratch
after this pass.
Another reason for doing this is that SILowerControlFlow preserves
LiveIntervals which transitively requires MachineDominatorTree. I think
that means that SILowerControlFlow is obliged to preserve
MachineDominatorTree too as explained here:
https://lists.llvm.org/pipermail/llvm-dev/2020-November/146923.html
although it does not seem to have caused any problems in practice yet.
Differential Revision: https://reviews.llvm.org/D111313
In a couple of places machine verification was disabled for no apparent
reason, probably just because an "addPass(..., false)" line was cut and
pasted from elsewhere.
After this patch the only remaining place where machine verification is
disabled in the generic TargetPassConfig code, is after addPreEmitPass.
DecompGEP.Base and UnderlyingV are currently always the same.
However, logically DecompGEP.Base is the right value to use here,
because the decomposed offset is relative to that base.
LoopFlatten does preserve loop analyses (DT, LI and SCEV), but
currently doesn't mark them as preserved in the NewPM (they are
marked as preserved in the LegacyPM). I think this doesn't really
have an effect in the end because the loop pass adaptor will just
assume they're preserved anyway, but let's be explicit about this
for the sake of clarity.
Differential Revision: https://reviews.llvm.org/D111328
When PHIElimination adds kills after lowering PHIs to COPYs it knows
that some instructions after the inserted COPY might use the same
SrcReg, but it was only looking at the terminator instructions at the
end of the block, not at other instructions like INLINEASM_BR that can
appear after the COPY insertion point.
Since we have already called findPHICopyInsertPoint, which knows about
INLINEASM_BR, we might as well reuse the insertion point that it
calculated when looking for instructions that might use SrcReg.
This fixes a machine verification failure if you force machine
verification to run after PHIElimination (currently it is disabled for
other reasons) when running
test/CodeGen/X86/callbr-asm-phi-placement.ll.
Differential Revision: https://reviews.llvm.org/D110834
Summary:
The IR is saved in its print form before each pass is started and a
signal handler is registered. If the compilation crashes, the signal
handler will print the saved IR to dbgs(). This option
can be modified using -print-module-scope to get the IR for the complete
module. Filtering options can be used to improve performance by limiting
which passes (or functions) save the IR. Note that this option only works
with the new pass manager.
Author: Jamie Schmeiser <schmeise@ca.ibm.com>
Reviewed By: aeubanks (Arthur Eubanks) yrouban (Yevgeny Rouban)
Differential Revision: https://reviews.llvm.org/D86657
X86InstrInfo::convertToThreeAddress would convert this:
%1:gr32 = ADD32rr killed %0:gr32(tied-def 0), %0:gr32, implicit-def dead $eflags
to this:
undef %2.sub_32bit:gr64 = COPY killed %0:gr32
undef %3.sub_32bit:gr64_nosp = COPY %0:gr32
%1:gr32 = LEA64_32r killed %2:gr64, 1, killed %3:gr64_nosp, 0, $noreg
Note that in the ADD32rr, %0 was used twice and the first use had a kill
flag, which is what MachineInstr::addRegisterKilled does.
In the converted code, each use of %0 is copied to a new reg, and the
first COPY inherits the kill flag from the ADD32rr. This causes
machine verification to fail (if you force it to run after
TwoAddressInstructionPass) because the second COPY uses %0 after it is
killed. Note that machine verification is currently disabled after
TwoAddressInstructionPass but this is a step towards being able to
enable it.
Fix this by not inserting more than one COPY from the same source
register.
Differential Revision: https://reviews.llvm.org/D110829
In the review of D111085 it was pointed out that these functions don't
conform to the naming scheme in use in LLVM. With this commit we should
be good for all of FPEnv.h.
Print this basic block flag as inlineasm-br-indirect-target and parse
it. This allows you to write MIR test cases for INLINEASM_BR. The test
case I added is one that I wanted to precommit anyway for D110834.
Differential Revision: https://reviews.llvm.org/D111291
This patch fixes problems reported in PR51981.
When rotating a loop it isn't enough to just forget SCEV for that
loop nest. When rotating we might clone some instructions from the
old header into the preheader, and insert new PHI nodes to merge
values together. There could be users of the original value that are
updated to use the PHI result. And those users were not necessarily
depending on a PHI node earlier, so they weren't cleaned up when just
forgetting all SCEV:s for the loop nest. So we need to explicitly
forget those values to avoid invalid cached SCEV expressions.
Reviewed By: fhahn, mkazantsev
Differential Revision: https://reviews.llvm.org/D110813
SCEV-based salvaging will use excessive resources if it encounters
very long SCEV expressions. This patch places a limit on the length of
SCEV expression that salvaging will attempt to translate.
Reviewed by: Orlando
Differential Revision: https://reviews.llvm.org/D110558
Based on the reasoning of D53903, register operands of DBG_VALUE are
invariably treated as RegState::Debug operands. This change enforces
this invariant as part of MachineInstr::addOperand so that all passes
emit this flag consistently.
RegState::Debug is inconsistently set on DBG_VALUE registers throughout
LLVM. This runs the risk of a filtering iterator like
MachineRegisterInfo::reg_nodbg_iterator to process these operands
erroneously when not parsed from MIR sources.
This issue was observed in the development of the llvm-mos fork which
adds a backend that relies on physical register operands much more than
existing targets. Physical RegUnit 0 has the same numeric encoding as
$noreg (indicating an undef for DBG_VALUE). Allowing debug operands into
the machine scheduler correlates $noreg with RegUnit 0 (i.e. a collision
of register numbers with different zero semantics). Eventually, this
causes an assert where DBG_VALUE instructions are prohibited from
participating in live register ranges.
Reviewed By: MatzeB, StephenTozer
Differential Revision: https://reviews.llvm.org/D110105
Currently when creating tail predicated loops, we need to validate that
all the live-outs of a loop will be equivalent with and without tail
predication, and if they are not we cannot legally create a
tail-predicated loop, leaving expensive vctp and vpst instructions in
the loop. These notably can include register-allocation instructions
like stack loads and stores, and copys lowered from COPYs to MVE_VORRs.
Instead of trying to prove this is valid late in the pipeline, this
patch introduces a MQPRCopy pseudo instruction that COPY is lowered to.
This can then either be converted to a MVE_VORR where possible, or to a
couple of VMOVD instructions if not. This way they do not behave
differently within and outside of tail-predications regions, and we can
know by construction that they are always valid. The idea is that we can
do the same with stack load and stores, converting them to VLDR/VSTR or
VLDM/VSTM where required to prove tail predication is always valid.
This does unfortunately mean inserting multiple VMOVD instructions,
instead of a single MVE_VORR, but my experiments show it to be an
improvement in general.
Differential Revision: https://reviews.llvm.org/D111048
Fix the calculation of ReplacedAllUntiedUses when any of the tied defs
are early-clobber. The effect of this is to fix the placement of kill
flags on an instruction like this (from @f2 in
test/CodeGen/SystemZ/asm-18.ll):
INLINEASM &"stepb $1, $2" [attdialect], $0:[regdef-ec:GRH32Bit], def early-clobber %3:grh32bit, $1:[reguse tiedto:$0], killed %4:grh32bit(tied-def 3), $2:[reguse:GRH32Bit], %4:grh32bit
After TwoAddressInstruction without this patch:
%3:grh32bit = COPY killed %4:grh32bit
INLINEASM &"stepb $1, $2" [attdialect], $0:[regdef-ec:GRH32Bit], def early-clobber %3:grh32bit, $1:[reguse tiedto:$0], %3:grh32bit(tied-def 3), $2:[reguse:GRH32Bit], %4:grh32bit
Note that the COPY kills %4, even though there is a later use of %4 in
the INLINEASM. This fails machine verification if you force it to run
after TwoAddressInstruction (currently it is disabled for other
reasons).
After TwoAddressInstruction with this patch:
%3:grh32bit = COPY %4:grh32bit
INLINEASM &"stepb $1, $2" [attdialect], $0:[regdef-ec:GRH32Bit], def early-clobber %3:grh32bit, $1:[reguse tiedto:$0], %3:grh32bit(tied-def 3), $2:[reguse:GRH32Bit], %4:grh32bit
Differential Revision: https://reviews.llvm.org/D110848
Changes in architecture revision 00eac1:
* Renamed to PSEL.
* Copies whole source register.
* Element type suffix removed from destination.
* Element index no longer optional and '#' prefix has been removed.
The reference can be found here:
https://developer.arm.com/documentation/ddi0602/2021-09
Depends on D111212.
Reviewed By: kmclaughlin
Differential Revision: https://reviews.llvm.org/D111213
Changes in architecture revision 00eac1:
* Tile slice index offset no longer prefixed with '#'.
* The syntax for 128-bit (.Q) ZA tile slice accesses must now include
an explicit zero index.
The reference can be found here:
https://developer.arm.com/documentation/ddi0602/2021-09
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D111212
To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunction
(D109792), the function is renamed to getAliaseeObject.
This reverts c7f16ab3e3 / r109694 - which
suggested this was done to improve consistency with the gdb test suite.
Possible that at the time GCC did not canonicalize integer types, and so
matching types was important for cross-compiler validity, or that it was
only a case of over-constrained test cases that printed out/tested the
exact names of integer types.
In any case neither issue seems to exist today based on my limited
testing - both gdb and lldb canonicalize integer types (in a way that
happens to match Clang's preferred naming, incidentally) and so never
print the original text name produced in the DWARF by GCC or Clang.
This canonicalization appears to be in `integer_types_same_name_p` for
GDB and in `TypeSystemClang::GetBasicTypeEnumeration` for lldb.
(I tested this with one translation unit defining 3 variables - `long`,
`long (*)()`, and `int (*)()`, and another translation unit that had
main, and a function that took `long (*)()` as a parameter - then
compiled them with mismatched compilers (either GCC+Clang, or
Clang+(Clang with this patch applied)) and no matter the combination,
despite the debug info for one CU naming the type "long int" and the
other naming it "long", both debuggers printed out the name as "long"
and were able to correctly perform overload resolution and pass the
`long int (*)()` variable to the `long (*)()` function parameter)
Did find one hiccup, identified by the lldb test suite - that CodeView
was relying on these names to map them to builtin types in that format.
So added some handling for that in LLVM. (these could be split out into
separate patches, but seems small enough to not warrant it - will do
that if there ends up needing any reverti/revisiting)
Differential Revision: https://reviews.llvm.org/D110455
When checking to see if we can apply IR flags to a SCEV, we need to identify a bound on the defining scope of the SCEV to be produced. We'd previously added support for a couple SCEVExpr types which trivially imply bounds, but hadn't handled types such as umax where the bounds come from the bounds of the operands. This does the obvious thing, and recurses through operands searching for a tighter bound on the defining scope.
I'm honestly surprised by how little this seems to mater on existing tests, but it's worth doing for completeness sake alone.
Differential Revision: https://reviews.llvm.org/D111191
Without popcnt we had a special case for using the parity flag from a single test i8 test instruction if only bits 7:0 could be non-zero. That special case is still useful when we have popcnt.
To reach this special case, we enable custom lowering of parity for i16/i32/i64 even when popcnt is enabled. The check for POPCNT being enabled is now after the special case in LowerPARITY.
Fixes PR52093
Differential Revision: https://reviews.llvm.org/D111249
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
When determining the defining scope, avoid repeatedly querying
dominationg against the function entry instruction. This ends up
begin a very common case that we can handle more efficiently.
isAllOnes() should return true for zero bit values because
there are no zeros in it.
Thanks to Jay Foad for pointing this out.
Differential Revision: https://reviews.llvm.org/D111241
This does for readability of returns within said function as what we do for the caller side when reasoning about what might be poison.
Differential Revision: https://reviews.llvm.org/D111180
Lowering of byval parameters with sizes that are not represented by a single
store require multiple stores to properly address the correct size of the
parameter.
Sizes that cannot be done with a single store are 3 bytes, 5 bytes, 6 bytes,
7 bytes. It is not correct to simply perform an 8 byte store and for these
elements because then the store would be larger than the element and alias
analysis would assume that this is undefined behaivour and return NoAlias
for them.
This patch adds the correct stores so that the size of the store is not larger
than the size of the element.
Reviewed By: nemanjai, #powerpc
Differential Revision: https://reviews.llvm.org/D108795
This patch removes a compile time restriction from isSCEVExprNeverPoison. We've strengthened our ability to reason about flags on scopes other than addrecs, and this bailout prevents us from using it. The comment is also suspect as well in that we're in the middle of constructing a SCEV for I. As such, we're going to visit all operands *anyways*.
Differential Revision: https://reviews.llvm.org/D111186
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
Currently the fadd optimizations in InstSimplify don't know how to do this
"X + -0.0 ==> X" fold when using the constrained intrinsics. This adds the
support.
This commit is derived from D106362 with some improvements from D107285.
Differential Revision: https://reviews.llvm.org/D111085
D100244 missed a check on the ResNo of the extract's operand 0 when finding a
pair of extracts to combine into a VMOVRRD (extract(x, n); extract(x, n+1) ->
VMOVRRD(extract x, n/2)). As a result, it can incorrectly pair an extract(x, n)
with another extract(x:3, n+1) for example. This patch fixes the bug by adding
the proper check on ResNo.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D111188
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.
This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.
The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.
Updating clang's max allowed alignment will come in a future patch.
Reviewed By: hans
Differential Revision: https://reviews.llvm.org/D110451
BasicAA GEP decomposition currently performs all calculation on the
maximum pointer size, but at least 64-bit, with an option to double
the size. The code comment claims that this improves analysis power
when working with uint64_t indices on 32-bit systems. However, I don't
see how this can be, at least while maintaining correctness:
When working on canonical code, the GEP indices will have GEP index
size. If the original code worked on uint64_t with a 32-bit size_t,
then there will be truncs inserted before use as a GEP index. Linear
expression decomposition does not look through truncs, so this will
be an opaque value as far as GEP decomposition is concerned. Working
on a wider pointer size does not help here (or have any effect at all).
When working on non-canonical code (before first InstCombine), the
GEP indices are implicitly truncated to GEP index size. The BasicAA
code currently just ignores this fact completely, and pretends that
this truncation doesn't happen. This is incorrect and will be
addressed by D110977.
I believe that for correctness reasons, it is important to work on
the actual GEP index size to properly model potential overflow.
BasicAA tries to patch over the fact that it uses the wrong size
(see adjustToPointerSize), but it only does that in limited cases
(only for constant values, and not all of them either). I'd like to
move this code towards always working on the correct size, and
dropping these artificial pointer size adjustments is the first step
towards that.
Differential Revision: https://reviews.llvm.org/D110657
https://alive2.llvm.org/ce/z/QagQMn
This fold is handled by instcombine via SimplifyUsingDistributiveLaws(),
but we are missing the sibliing fold for 'logical and' (implemented with
'select'). Retrofitting the code in instcombine looks much harder
than just adding a small adjustment here, and this is potentially more
efficient and beneficial to other passes.
We need to be better at exposing the comparison predicate to getCmpSelInstrCost calls as some targets (e.g. X86 SSE) have very different costs for different comparisons (PR48337), and we can't always rely on the optional Instruction argument.
This initial commit requires explicit condition type and predicate arguments. The next step will be to review a lot of the existing getCmpSelInstrCost calls which have used BAD_ICMP_PREDICATE even when the predicate is known.
Differential Revision: https://reviews.llvm.org/D111024
As described on D111049, removing the <string> dependency from error handling removes considerable build overhead, its recommended that the report_fatal_error(Twine) variant is used instead.
This patch add a TableManager which reponsible for fixing edges that need entries to reference the target symbol and constructing such entries.
In the past, the PerGraphGOTAndPLTStubsBuilder pass was used to build GOT and PLT entry, and the PerGraphTLSInfoEntryBuilder pass was used to build TLSInfo entry. By generalizing the behavior of building entry, I added a TableManager which could be reused when built GOT, PLT and TLSInfo entries.
If this patch makes sense and can be accepted, I will apply the TableManager to other targets(MachO_x86_64, MachO_arm64, ELF_riscv), and delete the file PerGraphGOTAndPLTStubsBuilder.h
Reviewed By: lhames
Differential Revision: https://reviews.llvm.org/D110383
We already handle more complicated cases like:
extelt (bitcast (inselt poison, X, 0)) --> trunc (lshr X)
But we missed this simpler pattern:
https://alive2.llvm.org/ce/z/D55h64 / https://alive2.llvm.org/ce/z/GKzzRq
This is part of solving:
https://llvm.org/PR52057
I made the transform depend on legal/desirable int type to avoid creating
a shift of an illegal type (for example i128). I'm not sure if that
restriction is actually necessary, but we can change that as a follow-up
if the backend can deal with integer ops on too-wide illegal types.
The pile of AVX512 test changes are all neutral AFAICT - the x86 backend
seems to know how to turn that into the expected "kmov" instructions.
Differential Revision: https://reviews.llvm.org/D111082
As described on D111049, we're trying to remove the <string> dependency from error handling and replace uses of report_fatal_error(const std::string&) with the Twine() variant which can be forward declared.
As described on D111049, we're trying to remove the <string> dependency from error handling and replace uses of report_fatal_error(const std::string&) with the Twine() variant which can be forward declared.
The X86 backend only needs to know whether structure return is via an
sret pointer. This removes the categorization enumeration and
adjusts, templatizes and renames the related functions.
Differential Revision: https://reviews.llvm.org/D109966
As suggested on D111024, we should treat getCmpSelInstrCost calls without a specific predicate as matching the worst case predicate cost.
These regressions will be addressed with a mixture of D111024 and fixing other specific getCmpSelInstrCost calls to have realistic predicates.
Seem to cause test failures in compiler-rt.
Revert "[SystemZ] Implement memcmp of variable length with CLC."
This reverts commit 7a4e9a0c73.
Revert "[SystemZ] Implement memcpy of variable length with MVC."
This reverts commit c6c13c58ee.
We were previously silently generating incorrect code when extracting a
fixed-width vector from a scalable vector. This is worse than crashing,
since the user will have no indication that this is currently unsupported
behaviour. I have fixed the code to only perform DAG combines when safe
to do so, i.e. the input and output vectors are both fixed-width or
both scalable.
Test added here:
CodeGen/AArch64/sve-extract-scalable-vector.ll
Differential revision: https://reviews.llvm.org/D110624
The currently implementation of funcrefs is broken since it is putting
the funcref itself on the stack before the call_indirect. Instead what
should be on the stack is the constant 0, which is the index at which
we store the funcref in __funcref_call_table.
Reviewed By: tlively
Differential Revision: https://reviews.llvm.org/D111152
This is a non-functional change to remove the duplicate
WasmAddressSpace enum and refactor reftype predicates by moving them
to the Utilities source file.
Reviewed By: tlively
Differential Revision: https://reviews.llvm.org/D111144
If these blocks are unreachable, then we can discard all of the instructions.
However, keep the block around because it may have an address taken or the
block may have a stale reference from a PHI somewhere. Instead of finding
those PHIs and fixing them up, just leave the block empty.
Differential Revision: https://reviews.llvm.org/D111201
Without this change _term instructions can be removed during
critical edge splitting.
Reviewed By: foad
Differential Revision: https://reviews.llvm.org/D111126
This removes `WasmTagType`. `WasmTagType` contained an attribute and a
signature index:
```
struct WasmTagType {
uint8_t Attribute;
uint32_t SigIndex;
};
```
Currently the attribute field is not used and reserved for future use,
and always 0. And that this class contains `SigIndex` as its property is
a little weird in the place, because the tag type's signature index is
not an inherent property of a tag but rather a reference to another
section that changes after linking. This makes tag handling in the
linker also weird that tag-related methods are taking both `WasmTagType`
and `WasmSignature` even though `WasmTagType` contains a signature
index. This is because the signature index changes in linking so it
doesn't have any info at this point. This instead moves `SigIndex` to
`struct WasmTag` itself, as we did for `struct WasmFunction` in D111104.
In this CL, in lib/MC and lib/Object, this now treats tag types in the
same way as function types. Also in YAML, this removes `struct Tag`,
because now it only contains the tag index. Also tags set `SigIndex` in
`WasmImport` union, as functions do.
I think this makes things simpler and makes tag handling more in line
with function handling. These two shares similar properties in that both
of them have signatures, but they are kind of nominal so having the same
signature doesn't mean they are the same element.
Also a drive-by fix: the reserved 'attirubute' part's encoding changed
from uleb32 to uint8 a while ago. This was fixed in lib/MC and
lib/Object but not in YAML. This doesn't change object files because the
field's value is always 0 and its encoding is the same for the both
encoding.
This is effectively NFC; I didn't mark it as such just because it
changed YAML test results.
Reviewed By: sbc100, tlively
Differential Revision: https://reviews.llvm.org/D111086
This also removes the need to disable the mandatory inlining phase in
tests.
In a departure from the previous remark, we don't output a 'cost' in
this case, because there's no such thing. We just report that inlining
happened because of the attribute.
Differential Revision: https://reviews.llvm.org/D110891
This removes repeated calls to m_Not, so hopefully a little
more efficient.
Also, we may need to enhance some of these blocks to allow
logical and/or (select of bools).