Similar to AVX1, the cost of splitting/merging 512-bit -> 256-bits vectors for arithmetic operations are typically hidden due to different used ports etc.
The VINSERTF128 instruction is often much quicker, and never slower, than the more general VPERM2F128 instruction, so we should try to use that in more circumstances.
This requires a fallback to a commuted VPERM2F128 for the case where we need to fold the 256-bit vector source instead of the 128-bit subvector source.
There is one interesting side effect - DAGCombine's narrowExtractedVectorLoad combine gets called in a number of locations, this often creates an extracted subvector load without regard to other uses of the original wider load. I'm expecting AVX cpus to be capable of merging such aliased loads, but I do wonder whether narrowExtractedVectorLoad's call to X86TargetLowering::shouldReduceLoadWidth needs to be altered to check for more partial uses?
Noticed while investigating the quality of interleaved load/store codegen.
Differential Revision: https://reviews.llvm.org/D111960
We never expect the runtime VF to be negative so we should use
the uitofp instruction instead of sitofp.
Differential revision: https://reviews.llvm.org/D112610
Now that the reasoning was added to ConstantRange in D90924,
this replicates IndVars variant of this transform (D111836)
in a pass that uses value range reasoning for the transform.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D112895
when Taildup hit loop with multiple latches like:
// 1 -> 2 <-> 3 |
// \ <-> 4 |
// \ <-> 5 |
// \---> rest |
it may transform this loop into multiple loops by duplicate loop header.
However, this change may has little benefit while makes cfg much complex.
In some uncommon cases, it causes large compile time regression (offered by
@alexfh in D106056).
This patch disable tail-duplicate of such cases.
TestPlan: check-llvm
Differential Revision: https://reviews.llvm.org/D110613
This function is used at least in 2 places, to it makes sense to make it separate.
Differential Revision: https://reviews.llvm.org/D112516
Reviewed By: reames
Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to BitcodeReader, change
clang to emit the correct type, and fix tests to comply.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D112349
Ooops. It constructs codegen infra and provide only basic code to generate first add instruction successfully.
Differential Revision: https://reviews.llvm.org/D112206
Otherwise we'll hit a spurious assert failure when we reset and then
reinitialize TimeProfiler on the same thread, as can happen when e.g.
using LLD as a library and running it multiple times in the same
process.
Makes `lld/test/MachO/time-trace.s` pass with `LLD_IN_TEST=2`, which
runs the linker twice in the same process and exposed the issue.
Reviewed By: MaskRay, mehdi_amini
Differential Revision: https://reviews.llvm.org/D112880
For certain combination of LHS and RHS constant ranges,
the signedness of the relational comparison predicate is irrelevant.
This implements complete and precise model for all predicates,
as confirmed by the brute-force tests. I'm not sure if there are
some more cases that we can handle here.
In a follow-up, CVP will make use of this.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D90924
MachOPlatform used to make an EPC-call (registerObjectSections) to register the
eh-frame and thread-data sections for each linked object with the ORC runtime.
Now that JITLinkMemoryManager supports allocation actions we can use these
instead of an EPC call. This saves us one EPC-call per object linked, and
manages registration/deregistration in the executor, rather than the controller
process. In the future we may use this to allow JIT'd code in the executor to
outlive the controller object while still being able to be cleanly destroyed.
Since the code for allocation actions must be available when the actions are
run, and since the eh-frame registration code lives in the ORC runtime itself,
this change required that MachO eh-frame support be split out of
macho_platform.cpp and into its own macho_ehframe_registration.cpp file that has
no other dependencies. During bootstrap we start by forcing emission of
macho_ehframe_registration.cpp so that eh-frame registration is guaranteed to be
available for the rest of the bootstrap process. Then we load the rest of the
MachO-platform runtime support, erroring out if there is any attempt to use
TLVs. Once the bootstrap process is complete all subsequent code can use all
features.
Alloc actions should return a CWrapperFunctionResult. JITLink does not have
access to this type yet, due to library layering issues, so add a cut-down
version with a fixme.
This type has been moved up into the llvm::orc::shared namespace.
This type was originally put in the detail:: namespace on the assumption that
few (if any) LLVM source files would need to use it. In practice it has been
needed in many places, and will continue to be needed until/unless
OrcTargetProcess is fully merged into the ORC runtime.
As noted in https://reviews.llvm.org/D90924#inline-1076197
apparently this is a pretty common pattern,
let's not repeat it yet again, but have it in a common place.
There may be some more places where it could be used,
but these are the most obvious ones.
The maximal value of a half is 0x7bff, which is 65504 when converted to
an integer. This patch teaches that to computeConstantRange to compute a
constant range with the correct maximum value.
https://alive2.llvm.org/ce/z/BV_Spbhttps://alive2.llvm.org/ce/z/Nwuqvb
The maximum value for a float converted in the same way is 3.4e38, which
requires 129bits of data. I have not added that here as integer types so
larger are rare, compared to integers types larger than 17 bits require
for half floats.
The MVE tests change because instsimplify happens to be run as a part of
the backend, where it doesn't tend to for other backends.
Differential Revision: https://reviews.llvm.org/D112694
Register operands with superclasses can possibly have multiple regBanks
if they have different register types. The regBank ambiguity resolved
during regbankselect should be used to constrain the operand regclass
instead of obtaining one from the MCInstrDesc.
This is a prerequisite patch for D109300 that introduces allocatable AV_*
Superclasses for AMDGPU by combining both VGPRs and AGPRs and we want to
restrain the regclass to either A or V based on the incoming regbank.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D112323
fs::copy_file() on Darwin has a nice optimization to clone the file when
possible. Change the implementation to use clonefile() directly, instead
of the higher-level copyfile(). The latter does the wrong thing for
symlinks, which requires calling `stat` first...
With that out of the way, optimistically call clonefile() all the time,
and then for any error that's recoverable try again with copyfile()
(without the COPYFILE_CLONE flag, as before).
Differential Revision: https://reviews.llvm.org/D112250
With Global ISel getReservedRegs() is called before function is
regbank selected for the first time. Defer caching of usesAGPRs()
in this case.
Differential Revision: https://reviews.llvm.org/D112644
This patch adds support to remove stores that write the same value
as earlier memesets.
It uses isOverwrite to check that a memset completely overwrites a later
store. The candidate store must store the same bytewise value as the
byte stored by the memset.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D112321
The scale multiplication is only guaranteed to be nsw if the GEP
is inbounds (or the multiplication is trivial). Previously we were
only considering explicit muls in GEP indices.
These compiler-rt-only symbols aren't available in libgcc. Similar to
D108842, D108844, and D108926.
Fixes: pr/52043
Reviewed By: craig.topper, rengolin
Differential Revision: https://reviews.llvm.org/D112750
The tests are based on the example from:
https://llvm.org/PR52032
I suspect that it looks worse than it actually is. :)
That is, llvm-mca says there's no uop/timing difference with the
load folding and pcmpeq vs. broadcast on Haswell (and probably
other targets).
The load-folding definitely makes the code smaller, so it's good
for that at least. So this requires carving a narrow hole in the
transform to get just this case without changing others that look
good as-is (in other words, the transform still seems good for
most examples).
Differential Revision: https://reviews.llvm.org/D112464
Adds the following switches:
1. --sample-profile-inline-replay-fallback/--cgscc-inline-replay-fallback: controls what the replay advisor does for inline sites that are not present in the replay. Options are:
1. Original: defers to original advisor
2. AlwaysInline: inline all sites not in replay
3. NeverInline: inline no sites not in replay
2. --sample-profile-inline-replay-format/--cgscc-inline-replay-format: controls what format should be generated to match against the replay remarks. Options are:
1. Line
2. LineColumn
3. LineDiscriminator
4. LineColumnDiscriminator
Adds support for negative inlining decisions. These are denoted by "will not be inlined into" as compared to the positive "inlined into" in the remarks.
All of these together with the previous `--sample-profile-inline-replay-scope/--cgscc-inline-replay-scope` allow tweaking in how to apply replay. In my testing, I'm using:
1. --sample-profile-inline-replay-scope/--cgscc-inline-replay-scope = Function to only replay on a function
2. --sample-profile-inline-replay-fallback/--cgscc-inline-replay-fallback = NeverInline since I'm feeding in only positive remarks to the replay system
3. --sample-profile-inline-replay-format/--cgscc-inline-replay-format = Line since I'm generating the remarks from DWARF information from GCC which can conflict quite heavily in column number compared to Clang
An alternative configuration could be to do Function, AlwaysInline, Line fallback with negative remarks which closer matches the final call-sites. Note that this can lead to unbounded inlining if a negative remark doesn't match/exist for one reason or another.
Updated various tests to cover the new switches and negative remarks
Testing:
ninja check-all
Reviewed By: wenlei, mtrofin
Differential Revision: https://reviews.llvm.org/D112040
Use the new sys::path::is_style_posix() and is_style_windows() in a few
places that need to detect the system's native path style.
In llvm/lib/Support/Path.cpp, this patch removes most uses of the
private `real_style()`, where is_style_posix() and is_style_windows()
are just a little tidier.
Elsewhere, this removes `_WIN32` macro checks. Added a FIXME to a
FileManagerTest that seemed fishy, but maintained the existing
behaviour.
Differential Revision: https://reviews.llvm.org/D112289
Replay in sample profiling needs to be asked on candidates that may not have counts or below the threshold. If replay is in effect for a function make sure these are captured and also imported during thinLTO.
Testing:
ninja check-all
Reviewed By: wenlei
Differential Revision: https://reviews.llvm.org/D112033
Expose three helpers in namespace llvm::sys::path to detect the
path rules followed by sys::path::Style.
- is_style_posix()
- is_style_windows()
- is_style_native()
This are constexpr functions that that will allow a bunch of
path-related code to stop checking `_WIN32`.
Originally I looked at adding system_style(), analogous to
sys::endian::system_endianness(), but future patches (from others) will
add more Windows style variants for slash preferences. These helpers
should be resilient to that change, allowing callers to detect basic
path rules.
Differential Revision: https://reviews.llvm.org/D112288
`classifyLocalReference(nullptr)` is called to get the appropriate
relocation type for jump tables. We should not use @GOTPCREL for this
case.
The new test cases trigger assertions without this patch.
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D112832
This patch removes an internal failure found in FindMemType and "bubbles
it up" to the users of that method: GenWidenVectorLoads and
GenWidenVectorStores. FindMemType -- renamed findMemType -- now returns
an optional value, returning None if no such type is found.
Each of the aforementioned users now pre-calculates the list of types it
will use to widen the memory access. If the type breakdown is not
possible they will signal a failure, at which point the compiler will
crash as it does currently.
This patch is preparing the ground for alternative legalization
strategies for vector loads and stores, such as using vector-predication
versions of loads or stores.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112000
If the VL operand of a mask register instruction comes from an
explicit vsetvli with a different VTYPE, we can still avoid needing
a vsetvli as long as the SEW/LMUL ratio is the same and policy bits
match.
Differential Revision: https://reviews.llvm.org/D112762
Add support for generating TargetFrameIndex in complex patterns for
indexed addressing modes in SVE. Additionally, add missing load/stores
to getMemOpInfo and getLoadStoreImmIdx.
Differential Revision: https://reviews.llvm.org/D112617
createReplacementInstr was a trivial wrapper around
ConstantExpr::getAsInstruction, which also inserted the new instruction
into a basic block. Implement this directly in getAsInstruction by
adding an InsertBefore parameter and change all callers to use it. NFC.
A follow-up patch will remove createReplacementInstr.
Differential Revision: https://reviews.llvm.org/D112791
Change numBitsSigned to return the minimum size of a signed integer that
can hold the value. This is different by one from the previous result
but is more consistent with numBitsUnsigned. Update all callers. All
callers are now more consistent between the signed and unsigned cases,
and some callers get simpler, especially the ones that deal with
quantities like numBitsSigned(LHS) + numBitsSigned(RHS).
Differential Revision: https://reviews.llvm.org/D112813
As mentioned on D108539, when the gather indices are smaller than the pointer size, they are sign-extended BEFORE scale is applied, making the general fold unsafe.
If the index have sufficient sign-bits then folding the scale could be safe - I'll investigate this.
The sequence of instructions `xor (ashr X, BW-1), C` (or with a truncation
`xor (trunc (ashr X, BW-1)), C)` takes a value, produces all zeros or all
ones and with it optionally inverts a constant depending on whether the
original input was positive or negative. This is the same as checking if
the value is positive, and selecting between the constant and ~constant.
https://alive2.llvm.org/ce/z/NJ85qY
This is a fairly general version of a fold that helps pull saturating
arithmetic into a canonical form.
Differential Revision: https://reviews.llvm.org/D109151
This adds support for SVE structured loads/stores to the relevant target
hooks, such that we can support these instructions in the InterleavedAccess
pass.
Depends on D112078
Differential Revision: https://reviews.llvm.org/D112303
The TailDuplicator merged two blocks, even if the first one ended with
a terminator, resulting in invalid MIR, where a terminator is in the
middle of a block.
Abort merging if the first block ends with a terminator.
Differential Revision: https://reviews.llvm.org/D112226
Shift node is still needed to check if the shift is shr or shl to increment/decrement offset. Do not override the node.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D112733
The new name better suits the type.
This patch also changes the signature of the run method (it now returns a
WrapperFunctionResult), and adds runWithSPSRet methods that deserialize the
function result using SPS.
Together these chages bring this type into close alignment with its ORC runtime
counterpart.
Add i32x4.relaxed_trunc_f32x4_s, i32x4.relaxed_trunc_f32x4_u,
i32x4.relaxed_trunc_f64x2_s_zero, i32x4.relaxed_trunc_f64x2_u_zero.
These are only exposed as builtins, and require user opt-in.
Differential Revision: https://reviews.llvm.org/D112186
This is relanding commit da1d1a0869 .
This patch additionally addresses failures found in buildbots & post review comments.
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
Fixes non-determinisctic order of XOR instructions created after
5a7a458306. The order of call argument evaluation is not
defined, so create one Value before the call.
timm isn't the common case, and TImmLeafs should make it clear what
they are. We're adding a plain ImmLeaf for 0_65535, so rename
i64_imm0_65535 to timm64_0_65535, and imm32_0_7 to timm32_0_7.
`__stack_chk_guard` is a global variable that has no uses before the LLVM code generation phase (how it is defined is platform-dependent). LTO needs to preserve this symbol for that reason. Currently, legacy LTO API preserves it by hardcoding the logic in Internalizer, but this symbol is not preserved by regular LTO API in thinlink phase. This patch marks `__stack_chk_guard` used during IR symbol table writing since this is how builtin functions are preserved by thinlink by using `RuntimeLibcalls.def`.
Reviewed By: MaskRay, tejohnson
Differential Revision: https://reviews.llvm.org/D112595
Move the section collecting `AlwaysPreserved` up before any
`maybeInternalize` is called. Otherwise, functions in `AlwaysPreserved` (in this case, `__stack_chk_fail`)
are not preserved.
Reviewed By: MaskRay, tejohnson
Differential Revision: https://reviews.llvm.org/D112684
In function convertInstTo3Addr, after converting a two address instruction into
three address instruction, only the last new instruction is inserted into
DistanceMap. This is wrong, DistanceMap should track all instructions from the
beginning of current MBB to the working instruction. When a two address
instruction is converted to three address instruction, multiple instructions may
be generated (usually an extra COPY is generated), all of them should be
inserted into DistanceMap.
Similarly when unfolding memory operand in function tryInstructionTransform
DistanceMap is not maintained correctly.
Differential Revision: https://reviews.llvm.org/D111857
This extends `optimizeCompareInstr` to re-use previous comparison
results if the previous comparison was with an immediate that was 1
bigger or smaller. Example:
CMP x, 13
...
CMP x, 12 ; can be removed if we change the SETg
SETg ... ; x > 12 changed to `SETge` (x >= 13) removing CMP
Motivation: This often happens because SelectionDAG canonicalization
tends to add/subtract 1 often when optimizing for fallthrough blocks.
Example for `x > C` the fallthrough optimization switches true/false
blocks with `!(x > C)` --> `x <= C` and canonicalization turns this into
`x < C + 1`.
Differential Revision: https://reviews.llvm.org/D110867
`X86InstrInfo::optimizeCompareInstr` would only optimize a `SUB`
followed by a `CMP` in `isRedundantFlagInstr`. This extends the code to
also look for other combinations like `CMP`+`CMP`, `TEST`+`TEST`, `SUB
x,0`+`TEST`.
- Change `isRedundantFlagInstr` to run `analyzeCompareInstr` on the
candidate instruction and compare the results. This normalizes things
and gives consistent results for various comparisons (`CMP x, y`,
`SUB x, y`) and immediate cases (`TEST x, x`, `SUB x, 0`,
`CMP x, 0`...).
- Turn `isRedundantFlagInstr` into a member function so it can call
`analyzeCompare`. - We now also check `isRedundantFlagInstr` even if
`IsCmpZero` is true, since we now have cases like `TEST`+`TEST`.
Differential Revision: https://reviews.llvm.org/D110865
This patch updates recipe creation to ensure all
VPWidenIntOrFpInductionRecipes are in the header block. At the moment,
new induction recipes can be created in different blocks when trying to
optimize casts and induction variables.
Having all induction recipes in the header makes it easier to
analyze/transform them in VPlan.
Reviewed By: Ayal
Differential Revision: https://reviews.llvm.org/D111300
This is a (very) small move towards making the machine dominators more
aligned with the IR dominators:
* DominatorTree / MachineDomTree is the class holding the dominator tree
* DominatorTreeWrapperPass / MachineDominatorTree is the corresponding
(machine) function pass
This alignment will be used by analyses that are designed as templates
that work with LLVM IR as well as Machine IR.
Reviewed By: critson
Differential Revision: https://reviews.llvm.org/D112690
With D112160 and D112164, on a Chrome Mac build this reduces the total
size of CGProfile sections by 78% (around 25% eliminated entirely) and
total size of object files by 0.14%.
Differential Revision: https://reviews.llvm.org/D112655
This is relanding commit da1d1a0869 .
This patch additionally addresses failures found in buildbots & post review comments.
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
This extends the canonicalizeClampLike function to allow cases where the
input is truncated, but still matching on the types of the ICmps. For
example
%t = trunc i32 %X to i8
%a = add i32 %X, 128
%cmp = icmp ult i32 %a, 256
%c = icmp sgt i32 %X, -1
%f = select i1 %c, i8 High, i8 Low
%r = select i1 %cmp, i8 %t, i8 %f
becomes
%c1 = icmp slt i32 %X, -128
%c2 = icmp sge i32 %X, 128
%s1 = select i1 %c1, i32 sext(Low), i32 %X
%s2 = select i1 %c2, i32 sext(High), i32 %s1
%t = trunc i32 %s2 to i8
https://alive2.llvm.org/ce/z/vPzfxH
We limit the transform to constant High and Low values, where we know
the sext are free.
Differential Revision: https://reviews.llvm.org/D108049
That's https://reviews.llvm.org/D90328 follow-up.
This change eliminates writes to variables where the value that is being written is already stored in the variable.
This achieves the goal by looping through all memory definitions in the current state and getting defining access from each of them.
When there is defining access where the write instruction is identical to the original instruction it will remove this redundant write.
For example:
void f() {
x = 1;
if foo() {
x = 1;
g();
} else {
h();
}
}
void g();
void h();
The second x=1 will be eliminated since it is rewriting 1 to x. This pass will produce this:
void f() {
x = 1;
if foo() {
g();
} else {
h();
}
}
void g();
void h();
Differential Revision: https://reviews.llvm.org/D111727
If the index operand for a gather/scatter intrinsic is being scaled (self-addition or a shl-by-immediate) then we may be able to fold that scaling into the intrinsic scale immediate value instead.
Fixes PR13310.
Differential Revision: https://reviews.llvm.org/D108539
Gathered loads/extractelements/extractvalue instructions should be
checked if they can represent a vector reordering node too and their
order should ve taken into account for better graph reordering analysis/
Also, if the gather node has reused scalars, they must be reordered
instead of the scalars themselves.
Differential Revision: https://reviews.llvm.org/D112454
The motivating test is reduced from:
https://llvm.org/PR52261
Note that the more general problem of folding any binop into a multi-use
select of constants is still there. We need to ease the restriction in
InstCombinerImpl::FoldOpIntoSelect() to catch those. But these examples
never reach that code because Negator exclusively handles negation
patterns within visitSub().
Differential Revision: https://reviews.llvm.org/D112657
The newly added test previously caused the compiler to fail an
assertion. It looks like a strightforward TypeSize upgrade.
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D112142
mul24 intrinsic's operands are simplified by
AMDGPUTargetLowering::performIntrinsicWOChainCombine(). This change adds
the mul24hi intrinsics in the combine since its operands can be
simplified like that of the mul24 intrinsics.
Differential Revision: https://reviews.llvm.org/D112702
- Move the `s_and exec` to its correct position before the content of
the waterfall loop
- Use the SI_WATERFALL pseudo instruction, like for sdag, to benefit
from optimizations
- Add support for indirect function calls
To support indirect calls, add a G_SI_CALL instruction without register
class restrictions and insert a waterfall loop when applying register
banks.
Differential Revision: https://reviews.llvm.org/D109052
Save the instruction list of a block before selecting banks.
This allows to cope with moved instructions, even if they are reordered
or splitted into multiple basic blocks.
Differential Revision: https://reviews.llvm.org/D111223
The support for neoverse-512tvb mirrors the same option available in GCC[1].
There is no functional effect for this option yet.
This patch ensures the driver accepts "-mcpu=neoverse-512tvb", and enough
plumbing is in place to allow the new option to be used in the future.
[1]https://gcc.gnu.org/onlinedocs/gcc/AArch64-Options.html
Differential Revision: https://reviews.llvm.org/D112406
Since D81803 / 79657e2339, temp files
created on network shares don't set "Disposition.DeleteFile = true".
This flag normally takes care of removing the temp file both if the
process exits abnormally (either crashing or killed externally), and
when the file is closed cleanly.
For network shares, we voluntarily choose to not set the flag, and
if the operation to inspect the file handle (as a prerequisite to
setting the flag since 79657e2339)
fails we also error out. In both of these cases, we can at least make
sure to remove the temp files when they are closed cleanly.
Adjust the semantics of "OF_Delete" to not set the delete
disposition, but only set the access mode for allowing deletion.
Move the call to setDeleteDisposition into TempFile::create,
where we can check if it failed, and if it did, set a flag noting
that the file should be removed manually at the end.
This does leak files on crash, but at least doesn't leak files
in regular successful runs. (Technically, the alternative codepath
could use the RemoveFileOnSignal function, but that might complicate
the TempFile implementation further.)
This fixes https://github.com/mstorsjo/llvm-mingw/issues/233 and
https://bugs.llvm.org/show_bug.cgi?id=52080.
Differential Revision: https://reviews.llvm.org/D111875
Adding support to the CS preinliner to trim cold base profiles. This makes trimming consistent with the inline decision made by the preinliner. Also disable the existing profile merger when preinliner is on unless explicitly specified.
Reviewed By: wenlei, wlei
Differential Revision: https://reviews.llvm.org/D112489
Sync the order of Zvlsseg registers with vector registers to avoid
unnecessary register copies between vector instructions and zvlsseg
instructions.
Differential Revision: https://reviews.llvm.org/D110250
In the instruction encoding, the passthru register is always
tied to the destination register. The CPU scheduler has to wait
for the last writer of this register to finish executing before
the gather can start. This is true even if the initial mask is
all ones so that the passthru will never be used.
By explicitly zeroing the register we can break the false
dependency. The zero idiom is executed completing by the
register renamer and so is immedately considered ready.
Authored by Craig.
Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D112505
If we know the source operand of COPY is defined by a vector instruction
with tail agnostic and the same LMUL and there is no vsetvli between
COPY and the define instruction to change the vl and vtype, we could use
vmv.v.v or vmv.v.i to copy vector registers to get better performance than
the whole vector register move instructions.
If the source of COPY is from vmv.v.i, we could use vmv.v.i for the
COPY.
This patch only considers all these instructions within one basic block.
Case 1:
```
bb.0:
...
VSETVLI # The first VSETVLI before COPY and VOP.
... # Use this VSETVLI to check LMUL and tail agnostic.
...
vy = VOP va, vb # Define vy.
... # There is no vsetvli between VOP and COPY.
vx = COPY vy
```
Case 2:
```
bb.0:
...
VSETVLI # The first VSETVLI before VOP.
... # Use this VSETVLI to check LMUL and tail agnostic.
...
vy = VOP va, vb # Define vy.
... # There is no vsetvli to change vl between VOP and COPY.
...
VSETVLI # The first VSETVLI before COPY.
... # This VSETVLI does not change vl and vtype.
...
vx = COPY vy
```
Co-Authored-by: Zakk Chen <zakk.chen@sifive.com>
Co-Authored-by: Kito Cheng <kito.cheng@sifive.com>
Differential Revision: https://reviews.llvm.org/D103510
Following discussion in D110390, it seems that we are suffering from unability
to traverse users of a SCEV being invalidated. The result of that is that ScalarEvolution's
inner caches may store obsolete data about SCEVs even if their operands are
forgotten. It creates problems when we try to verify the contents of those caches.
It's also a frequent situation when messing with cache causes very sneaky and
hard-to-analyze bugs related to corruption of memory when dealing with cached
data. They are lurking there because ScalarEvolution's veirfication is not powerful
enough and misses many problematic cases. I plan to make SCEV's verification
much stricter in follow-ups, and this requires dangling-pointers-free caches.
This patch makes sure that, whenever we forget cached information for a SCEV,
we also forget it for all SCEVs that (transitively) use it.
This may have negative compile time impact. It's a sacrifice we are more
than willing to make to enforce correctness. We can also save some time by
reworking invokers of forgetMemoizedResults (maybe we can forget multiple
SCEVs with single query).
Differential Revision: https://reviews.llvm.org/D111533
Reviewed By: reames
Add new hasVInstructions() which is currently equivalent.
Replace vector uses of hasStdExtZfh/F/D with new vector specific
versions. The vector spec no longer requires that the vectors implement the
same types as scalar. It only requires that the scalar type is
the maximum size the vectors can support. This is currently
implemented using the scalar rule we were using before.
Add new hasVInstructionsI64() begin using to qualify code that
requires i64 vector elements.
This is all NFC for now, but we can start using this to better
implement D112408 which introduces the Zve extensions.
Reviewed By: frasercrmck, eopXD
Differential Revision: https://reviews.llvm.org/D112496
Even if we look for `nocapture` we need to bail on escaping pointers.
The crucial thing is that we might not look at a big enough scope when
we derive the memory behavior. Thus, it might be `nocapture` in a larger
context while it is "captured" in a smaller context.
In ARM mode, passing -mtp=cp15 forces the use of an inline MRC system register read to move the thread pointer value into a register.
Currently, in Thumb2 mode, -mtp=cp15 is ignored, and a call to the __aeabi_read_tp helper is emitted instead.
This is inconsistent, and breaks the Linux/ARM build for Thumb2 targets, as the Linux kernel does not provide an implementation of __aeabi_read_tp,.
Reviewed By: nickdesaulniers, peter.smith
Differential Revision: https://reviews.llvm.org/D112600
When we strip and accumulate constant offsets we need to pick the right
address space such that the offset APInt has the right bit width.
Reviewed By: JonChesterfield
Differential Revision: https://reviews.llvm.org/D112544
SPSExecutorAddr will now be serializable to/from ExecutorAddr, rather than
uint64_t. This improves type safety when working with serialized addresses.
Also updates the SupportFunctionCall to use an ExecutorAddrRange (rather than
a separate ExecutorAddr addr and uint64_t size field), and updates the
tpctypes::*Write data structures to use ExecutorAddr rather than
JITTargetAddress.
Upon further investigation and discussion,
this is actually the opposite direction from what we should be taking,
and this direction wouldn't solve the motivational problem anyway.
Additionally, some more (polly) tests have escaped being updated.
So, let's just take a step back here.
This reverts commit f3190dedee.
This reverts commit 749581d21f.
This reverts commit f3df87d57e.
This reverts commit ab1dbcecd6.
- When an unconditional branch is expanded into an indirect branch, if
there is no scavenged register, an SGPR pair needs spilling to enable
the destination PC calculation. In addition, before jumping into the
destination, that clobbered SGPR pair need restoring.
- As SGPR cannot be spilled to or restored from memory directly, the
spilling/restoring of that SGPR pair reuses the regular SGPR spilling
support but without spilling it into memory. As that spilling and
restoring points are fully controlled, we only need to spill that SGPR
into the temporary VGPR, which needs spilling into its emergency slot.
- The target-specific hook is revised to take additional restore block,
where the restoring code is filled. After that, the relaxation will
place that restore block directly before the destination block and
insert an unconditional branch in any fall-through block into the
destination block.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D106449
Enables the arm64 MachO platform, adds basic tests, and implements the
missing TLV relocations and runtime wrapper function. The TLV
relocations are just handled as GOT accesses.
rdar://84671534
Differential Revision: https://reviews.llvm.org/D112656
GEP decomposition currently checks whether the multiplication of
the linear expression offset and GEP scale overflows. However, if
everything else works correctly, this overflow check is both
unnecessary and dangerously misleading. While it will avoid an
overflow in Scale * Offset in particular, other parts of the
calculation (including those on dynamic values) may still overflow.
The code working on the decomposed GEPs is responsible for ensuring
that it remains correct in the presence of overflow. D112611 fixes
the last issue of that kind that I'm aware of (in fact, the overflow
check was originally introduced to work around precisely that issue).
Differential Revision: https://reviews.llvm.org/D112618
A constant complaint we get is that the __typeid__ symbols in the CFI
jump tables causes confusing stack traces in applications. Emit the more
readable cfi_jt aliases regardless of function export (LTO vs Thin LTO).
Reviewed By: pcc, tejohnson
Differential Revision: https://reviews.llvm.org/D107934
This method parallels the dropPoisonGeneratingFlags on Instruction, but is hoisted to operator to handle constant expressions as well.
This is mostly code movement, but I did go ahead and add the inrange constexpr gep case. This had been discussed previously, but apparently never followed up o.
It's a no-op, no overflow happens ever: https://alive2.llvm.org/ce/z/Zw89rZ
While generally i don't like such hacks,
we have a very good reason to do this: here we are expanding
a run-time correctness check for the vectorization,
and said `umul_with_overflow` will not be optimized out
before we query the cost of the checks we've generated.
Which means, the cost of run-time checks would be artificially inflated,
and after https://reviews.llvm.org/D109368 that will affect
the minimal trip count for which these checks are even evaluated.
And if they aren't even evaluated, then the vectorized code
certainly won't be run.
We could consider doing this in IRBuilder, but then we'd need to
also teach `CreateExtractValue()` to look into chain of `insertvalue`'s,
and i'm not sure there's precedent for that.
Refs. https://reviews.llvm.org/D109368#3089809
Gathered loads/extractelements/extractvalue instructions should be
checked if they can represent a vector reordering node too and their
order should ve taken into account for better graph reordering analysis/
Also, if the gather node has reused scalars, they must be reordered
instead of the scalars themselves.
Differential Revision: https://reviews.llvm.org/D112454
This patch changes the definition of getStepVector from:
Value *getStepVector(Value *Val, int StartIdx, Value *Step, ...
to
Value *getStepVector(Value *Val, Value *StartIdx, Value *Step, ...
because:
1. it seems inconsistent to pass some values as Value* and some as
integer, and
2. future work will require the StartIdx to be an expression made up
of runtime calculations of the VF.
In widenIntOrFpInduction I've changed the code to pass in the
value returned from getRuntimeVF, but the presence of the assert:
assert(!VF.isScalable() && "scalable vectors not yet supported.");
means that currently this code path is only exercised for fixed-width
VFs and so the patch is still NFC.
Differential revision: https://reviews.llvm.org/D111882
While we could emit such a tautological `select`,
it will stick around until the next instsimplify invocation,
which may happen after we count the cost of this redundant `select`.
Which is precisely what happens with loop vectorization legality checks,
and that artificially increases the cost of said checks,
which is bad.
There is prior art for this in `IRBuilderBase::CreateAnd()`/`IRBuilderBase::CreateOr()`.
Refs. https://reviews.llvm.org/D109368#3089809
PromoteIntRes_MLOAD always sets the extension type to `EXTLOAD`, which
results in a sign-extended load. If the type returned by getExtensionType()
for the load being promoted is something other than `NON_EXTLOAD`, we
should instead pass this to getMaskedLoad() as the extension type.
Reviewed By: CarolineConcatto
Differential Revision: https://reviews.llvm.org/D112320
Gathered loads/extractelements/extractvalue instructions should be
checked if they can represent a vector reordering node too and their
order should ve taken into account for better graph reordering analysis/
Also, if the gather node has reused scalars, they must be reordered
instead of the scalars themselves.
Differential Revision: https://reviews.llvm.org/D112454
Widens the result and first input vector because they have the same size.
The subvector to be inserted is widened in the operand widen function.
Differential Revision: https://reviews.llvm.org/D112187
BasicAA currently tries to determine that the offset is positive by
checking whether all variable indices are positive based on known
bits, multiplied by a positive scale. However, this is incorrect
if the scale multiplication might overflow. In the modified test
case the original value is positive, but may be negative after a
left shift.
Fix this by converting known bits into a constant range and reusing
the range-based logic, which handles overflow correctly.
Differential Revision: https://reviews.llvm.org/D112611
As noted in D112464, a pre-AVX target may not be able to fold an
under-aligned vector load into another op, so we shouldn't report
that as a load folding candidate. I only found one caller where
this would make a difference -- combineCommutableSHUFP() -- so
that's where I added a test to show the (minor) regression.
Differential Revision: https://reviews.llvm.org/D112545
Combine FADD and FMUL intrinsics into FMA when the result of the FMUL is an FADD operand
with one only use and both use the same predicate.
Differential Revision: https://reviews.llvm.org/D111638
This change introduces subtarget features to predicate certain
instructions and system registers that are available only on
'A' profile targets. Those features are not present when
targeting a generic CPU, which is the default processor.
In other words the generic CPU now means the intersection of
'A' and 'R' profiles. To maintain backwards compatibility we
enable the features that correspond to -march=armv8-a when the
architecture is not explicitly specified on the command line.
References: https://developer.arm.com/documentation/ddi0600/latest
Differential Revision: https://reviews.llvm.org/D110065
Need to emit select(cmp) instructions for poison-safe forms of select
ops. Currently alive reports that `Target is more poisonous than source`
for operations we generating for such instructions.
https://alive2.llvm.org/ce/z/FiNiAA
Differential Revision: https://reviews.llvm.org/D112562
Make the range check more precise by calculating the range of
potentially accessed bytes for both accesses and checking whether
their intersection is empty. In that case there can be no overlap
between the accesses and the result is NoAlias.
This is more powerful than the previous approach, because it can
deal with sign-wrapped ranges. In the test case the original range
is [-1, INT_MAX] but becomes [0, INT_MIN] after applying the offset.
This is a wrapping range, so getSignedMin/getSignedMax will treat
it as a full range. However, the range excludes the elements
[INT_MIN+1, -1], which is enough to prove NoAlias with an access
at offset -1.
Differential Revision: https://reviews.llvm.org/D112486
Add an optional bool RemoveDeadValNo argument to the
removeSegment(iterator) overload, for consistency with the other
overloads. This gives clients a way to remove dead valnos while also
getting an updated iterator returned (in the manner of vector::erase).
Use this to clean up some inefficient code in
LiveIntervals::repairOldRegInRange. NFC.
Differential Revision: https://reviews.llvm.org/D110560
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
I have removed LoopVectorizationPlanner::setBestPlan, since this
function is quite aggressive because it deletes all other plans
except the one containing the <VF,UF> pair required. The code is
currently written to assume that all <VF,UF> pairs will live in the
same vplan. This is overly restrictive, since scalable VFs live in
different plans to fixed-width VFS. When we add support for
vectorising epilogue loops when the main loop uses scalable vectors
then we will the vplan for the main loop will be different to the
epilogue.
Instead I have added a new function called
LoopVectorizationPlanner::getBestPlanFor
that returns the best vplan for the <VF,UF> pair requested and leaves
all the vplans untouched. We then pass this best vplan to
LoopVectorizationPlanner::executePlan
which now takes an additional VPlanPtr argument.
Differential revision: https://reviews.llvm.org/D111125
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