Details: To make instruction selection really divergence driven it is necessary to assign
the correct register classes to the cross block values beforehand. For the divergent targets
same value type requires different register classes dependent on the value divergence.
Reviewers: rampitec, nhaehnle
Differential Revision: https://reviews.llvm.org/D59990
llvm-svn: 361644
The new cortex-m schedule in rL360768 helps performance, but can increase the
amount of high-registers used. This, on average, ends up increasing the
codesize by a fair amount (because less instructions are converted from T2 to
T1). On cortex-m at -Oz, where we are quite size-paranoid, it is better to use
the existing DAG scheduler with the RegPressure scheduling preference (at least
until the issues around T2 vs T1 instructions can be improved).
I have also made sure that the Sched::RegPressure dag scheduler is always
chosen for MinSize.
The test shows one case where we increase the number of registers used.
Differential Revision: https://reviews.llvm.org/D61882
llvm-svn: 360769
This generally follows what other targets do. I don't completely
understand why the special case for tail calls existed in the first
place; even when the code was committed in r105413, call lowering didn't
work in the way described in the comments.
Stack protector lowering breaks if the register copies are not glued to
a tail call: we have to insert the stack protector check before the tail
call, and we choose the location based on the assumption that all
physical register dependencies of a tail call are adjacent to the tail
call. (See FindSplitPointForStackProtector.) This is sort of fragile,
but I don't see any reason to break that assumption.
I'm guessing nobody has seen this before just because it's hard to
convince the scheduler to actually schedule the code in a way that
breaks; even without the glue, the only computation that could actually
be scheduled after the register copies is the computation of the call
address, and the scheduler usually prefers to schedule that before the
copies anyway.
Fixes https://bugs.llvm.org/show_bug.cgi?id=41417
Differential Revision: https://reviews.llvm.org/D60427
llvm-svn: 360099
The MachineFunction wasn't used in getOptimalMemOpType, but more importantly,
this allows reuse of findOptimalMemOpLowering that is calling getOptimalMemOpType.
This is the groundwork for the changes in D59766 and D59787, that allows
implementation of TTI::getMemcpyCost.
Differential Revision: https://reviews.llvm.org/D59785
llvm-svn: 359537
This does two main things, firstly adding some at least basic addressing modes
for i64 types, and secondly treats floats and doubles sensibly when there is no
fpu. The floating point change can help codesize in some cases, especially with
D60294.
Most backends seems to not consider the exact VT in isLegalAddressingMode,
instead switching on type size. That is now what this does when the target does
not have an fpu (as the float data will be loaded using LDR's). i64's currently
use the address range of an LDRD (even though they may be legalised and loaded
with an LDR). This is at least better than marking them all as illegal
addressing modes.
I have not attempted to do much with vectors yet. That will need changing once
MVE is added.
Differential Revision: https://reviews.llvm.org/D60677
llvm-svn: 358845
As discussed on PR41359, this patch renames the pair of shift-mask target feature functions to make their purposes more obvious.
shouldFoldShiftPairToMask -> shouldFoldConstantShiftPairToMask
preferShiftsToClearExtremeBits -> shouldFoldMaskToVariableShiftPair
llvm-svn: 358526
There's an existing optimization for x != C, but somehow it was missing
a special case for 0.
While I'm here, also cleaned up the code/comments a bit: the second
value produced by the MERGE_VALUES was actually dead, since a CMOV only
produces one result.
Differential Revision: https://reviews.llvm.org/D59616
llvm-svn: 357437
This should hopefully lead to minor improvements in code generation, and
more accurate spill/reload comments in assembly.
Also fix isLoadFromStackSlotPostFE/isStoreToStackSlotPostFE so they
don't lead to misleading assembly comments for merged memory operands;
this is technically orthogonal, but in practice the relevant memory
operand lists don't show up without this change.
Differential Revision: https://reviews.llvm.org/D59713
llvm-svn: 356963
These changes are related to PR37743 and include:
SelectionDAGBuilder::visitSelect handles the unary SelectPatternFlavor::SPF_ABS case to build ABS node.
Delete the redundant recognizer of the integer ABS pattern from the DAGCombiner.
Add promoting the integer ABS node in the LegalizeIntegerType.
Expand-based legalization of integer result for the ABS nodes.
Expand-based legalization of ABS vector operations.
Add some integer abs testcases for different typesizes for Thumb arch
Add the custom ABS expanding and change the SAD pattern recognizer for X86 arch: The i64 result of the ABS is expanded to:
tmp = (SRA, Hi, 31)
Lo = (UADDO tmp, Lo)
Hi = (XOR tmp, (ADDCARRY tmp, hi, Lo:1))
Lo = (XOR tmp, Lo)
The "detectZextAbsDiff" function is changed for the recognition of pattern with the ABS node. Given a ABS node, detect the following pattern:
(ABS (SUB (ZERO_EXTEND a), (ZERO_EXTEND b))).
Change integer abs testcases for codegen with the ABS node support for AArch64.
Indicate that the ABS is legal for the i64 type when the NEON is supported.
Change the integer abs testcases to show changing of codegen.
Add combine and legalization of ABS nodes for Thumb arch.
Extend 'matchSelectPattern' to recognize the ABS patterns with ICMP_SGE condition.
For discussion, see https://bugs.llvm.org/show_bug.cgi?id=37743
Patch by: @ikulagin (Ivan Kulagin)
Differential Revision: https://reviews.llvm.org/D49837
llvm-svn: 356468
This allows better code size for aarch64 floating point materialization
in a future patch.
Reviewers: evandro
Differential Revision: https://reviews.llvm.org/D58690
llvm-svn: 356389
I am about to introduce some non-power-of-2 width vector MVTs. This
commit fixes a power-of-2 assumption that my forthcoming change would
otherwise break, as shown by test/CodeGen/ARM/vcvt_combine.ll and
vdiv_combine.ll.
Differential Revision: https://reviews.llvm.org/D58927
Change-Id: I56a282e365d3874ab0621e5bdef98a612f702317
llvm-svn: 356341
This uses the infrastructure added in rL353152 to sink zext and sexts to
sub/add users, to enable vsubl/vaddl generation when NEON is available.
See https://bugs.llvm.org/show_bug.cgi?id=40025.
Reviewers: SjoerdMeijer, t.p.northover, samparker, efriedma
Reviewed By: samparker
Differential Revision: https://reviews.llvm.org/D58063
llvm-svn: 355460
When lowering a select_cc node where the true and false values are of type f16,
we can't use a general conditional move because the FP16 instructions do not
support conditional execution. Instead, we must ensure that the condition code
is one of the four supported by the VSEL instruction.
Differential revision: https://reviews.llvm.org/D58813
llvm-svn: 355385
This function was not checking for the condition code variants which are
undefined if either input is NaN, so we were missing selection of the VSEL
instruction in some cases when using -fno-honor-nans or -ffast-math.
Differential revision: https://reviews.llvm.org/D58812
llvm-svn: 355199
Summary:
The description of KnownBits::zext() and
KnownBits::zextOrTrunc() has confusingly been telling
that the operation is equivalent to zero extending the
value we're tracking. That has not been true, instead
the user has been forced to explicitly set the extended
bits as known zero afterwards.
This patch adds a second argument to KnownBits::zext()
and KnownBits::zextOrTrunc() to control if the extended
bits should be considered as known zero or as unknown.
Reviewers: craig.topper, RKSimon
Reviewed By: RKSimon
Subscribers: javed.absar, hiraditya, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58650
llvm-svn: 355099
In many places in the backend, we like to know whether we're
optimising for code size and this is performed by checking the
current machine function attributes. A subtarget is created on a
per-function basis, so it's possible to know when we're compiling for
code size on construction so record this in the new object.
Differential Revision: https://reviews.llvm.org/D57812
llvm-svn: 353501
This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57173
llvm-svn: 352913
This broke the RISCV build, and even with that fixed, one of the RISCV
tests behaves surprisingly differently with asserts than without,
leaving there no clear test pattern to use. Generally it seems bad for
hte IR to differ substantially due to asserts (as in, an alloca is used
with asserts that isn't needed without!) and nothing I did simply would
fix it so I'm reverting back to green.
This also required reverting the RISCV build fix in r351782.
llvm-svn: 351796
This patch may seem familiar... but my previous patch handled the
equivalent lsls+and, not this case. Usually instcombine puts the
"and" after the shift, so this case doesn't come up. However, if the
shift comes out of a GEP, it won't get canonicalized by instcombine,
and DAGCombine doesn't have an equivalent transform.
This also modifies isDesirableToCommuteWithShift to suppress DAGCombine
transforms which would make the overall code worse.
I'm not really happy adding a bunch of code to handle this, but it would
probably be tricky to substantially improve the behavior of DAGCombine
here.
Differential Revision: https://reviews.llvm.org/D56032
llvm-svn: 351776
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This patch adds the sign/zero extension done by
vgetlane to ARM computeKnownBitsForTargetNode.
Differential revision: https://reviews.llvm.org/D56098
llvm-svn: 350553
This saves materializing the immediate. The additional forms are less
common (they don't usually show up for bitfield insert/extract), but
they're still relevant.
I had to add a new target hook to prevent DAGCombine from reversing the
transform. That isn't the only possible way to solve the conflict, but
it seems straightforward enough.
Differential Revision: https://reviews.llvm.org/D55630
llvm-svn: 349857
These features (fairly) recently got split out into their own feature, so we
should make CodeGen use them when available. The main change here is that the
check used to be based on the triple, but now it's based on CPU features.
llvm-svn: 349355
This has two positive effects. First, using a custom node prevents
recombination leading to an infinite loop since the output DAG is notionally a
little more complex than the input one. Using a flag-setting instruction also
allows the subtraction to be folded with the related comparison more easily.
https://reviews.llvm.org/D53190
llvm-svn: 348122
Don't expand SDIV with an immediate that is a power of 2 if we optimise for
minimum code size. For example:
sdiv %1, i32 4
gets expanded to a sequence of 3 instructions, but this is suboptimal for
minimum code size so instead we just generate a MOV and a SDIV if integer
division is supported.
Differential Revision: https://reviews.llvm.org/D54546
llvm-svn: 347965
The lowering was missing live-ins in certain cases, like a sequence of
multiple tMOVCCr_pseudo instructions. This would lead to a verifier
failure, and on pre-v6 Thumb CPSR would be incorrectly clobbered.
For reasons I don't completely understand, it's hard to get a sequence
of multiple tMOVCCr_pseudo instructions; the issue only seems to show up
with 64-bit comparisons where the result is zero-extended. I added some
extra testcases in case that changes in the future. Probably some
optimization opportunities here if anyone is interested. (@test_slt_not
is the case that was getting miscompiled.)
The code to check the liveness of CPSR was stolen from
X86ISelLowering.cpp; maybe it could be refactored into common helper,
but I have no idea where to put it.
Differential Revision: https://reviews.llvm.org/D54192
llvm-svn: 346355
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.
Reviewers: arsenm, aheejin, dschuff, javed.absar
Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D53112
llvm-svn: 345218
The BKPT instruction is specified to cause a software breakpoint,
and at least on Linux results in a SIGTRAP. This makes it more
suitable for implementing debugtrap than TRAP (aka UDF #254), which
is specified to cause an undefined instruction exception and results
in a SIGILL on Linux.
Moreover, BKPT is not marked as a terminator, which is not only
consistent with the IR instruction but allows the analyzeBlock
function to correctly analyze a basic block containing the instruction,
which fixes an assertion failure in the machine block placement pass
previously triggered by the included test case.
Because BKPT is only supported starting with ARMv5T, we continue to
use UDF #254 when targeting v4T.
Differential Revision: https://reviews.llvm.org/D53614
llvm-svn: 345171
A global alias may use indices which are not considered in bounds. In
such a case, accessing the base object will fail as it only peers
through inbounds accesses. This pattern is used by the swift compiler
to create references to preceeding members in the type metadata. This
would cause the code generation to fail when targeting a platform that
used ELF as the object file format. Be conservative and fail the
read-only check if we run into an alias that we cannot peer through.
llvm-svn: 345107
As I suggested on PR39281, this patch uses PADDL pairwise addition to widen from the vXi8 CTPOP result to the target vector type.
This is a blocker for moving more x86 code to generic vector CTPOP expansion (P32655 + D53258) - ARM's vXi64 CTPOP currently expands, which would generate a vXi64 MUL but ARM's custom lowering expands the general MUL case and vectors aren't well handled in LegalizeDAG - improving the CTPOP lowering was a lot easier than fixing the MUL lowering for this one case......
Differential Revision: https://reviews.llvm.org/D53257
llvm-svn: 344512
Correctly check for relocations in the constant to promote. And don't
allow promoting a constant multiple times.
This partially fixes https://bugs.llvm.org//show_bug.cgi?id=32780 ;
it's not a complete fix because we also need to prevent
ARMConstantIslands from cloning the constant.
(-arm-promote-constant is currently off by default, and it stays off
with this patch. I'll look into turning it on again when all the known
issues are fixed.)
Differential Revision: https://reviews.llvm.org/D51472
llvm-svn: 343361
This mostly affects IR generated by non-clang frontends because clang
generally sets the alignment of globals explicitly.
Fixes https://bugs.llvm.org//show_bug.cgi?id=32394 .
(-arm-promote-constant is currently off by default, and it stays off
with this patch. I'll look into turning it on again when all the known
issues are fixed.)
Differential Revision: https://reviews.llvm.org/D51469
llvm-svn: 343359
This involves changing the shouldExpandAtomicCmpXchgInIR interface, but I have
updated the in-tree backends using this hook (ARM, AArch64, Hexagon) so they
will see no functional change. Previously this hook returned bool, but it now
returns AtomicExpansionKind.
This hook allows targets to select how a given cmpxchg is to be expanded.
D48131 uses this to expand part-word cmpxchg to a target-specific intrinsic.
See my associated RFC for more info on the motivation for this change
<http://lists.llvm.org/pipermail/llvm-dev/2018-June/123993.html>.
Differential Revision: https://reviews.llvm.org/D48130
llvm-svn: 342550
The Technical Reference Manuals for these two CPUs state that branching
to an unaligned 32-bit instruction incurs an extra pipeline reload
penalty. That's bad.
This also enables the optimization at -Os since it costs on average one
byte per loop in return for 1 cycle per iteration, which is pretty good
going.
llvm-svn: 342127
On Windows, if shouldAssumeDSOLocal returns false, it's either a
dllimport reference, or a reference that we should treat as non-local
and create a stub for.
Clean up AArch64Subtarget::ClassifyGlobalReference a little while
touching the flag handling relating to dllimport.
Differential Revision: https://reviews.llvm.org/D51590
llvm-svn: 341402
The runtime pseudo relocations can't handle the ARM format embedded
addresses in movw/movt pairs. By using stubs, the potentially
dllimported addresses can be touched up by the runtime pseudo relocation
framework.
Differential Revision: https://reviews.llvm.org/D51450
llvm-svn: 341176
The inline sequence is very long (about 70 bytes on Thumb1), so it's
not really a good idea to inline it, especially when optimizing for
size.
Differential Revision: https://reviews.llvm.org/D47917
llvm-svn: 340458
This avoids a potential infinite loop setting and unsetting bits in the
mask.
Reduced from a failure on the polly-aosp bot.
Differential Revision: https://reviews.llvm.org/D51066
llvm-svn: 340446
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.
This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.
Differential Revision: https://reviews.llvm.org/D49673
llvm-svn: 340397
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.
Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.
This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.
This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.
As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]
Differential Revision: https://reviews.llvm.org/D50680
llvm-svn: 339740
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.
To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.
Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)
Differential Revision: https://reviews.llvm.org/D50667
llvm-svn: 339734
LLVM normally prefers to minimize the number of bits set in an AND
immediate, but that doesn't always match the available ARM instructions.
In Thumb1 mode, prefer uxtb or uxth where possible; otherwise, prefer
a two-instruction sequence movs+ands or movs+bics.
Some potential improvements outlined in
ARMTargetLowering::targetShrinkDemandedConstant, but seems to work
pretty well already.
The ARMISelDAGToDAG fix ensures we don't generate an invalid UBFX
instruction due to a larger-than-expected mask. (It's orthogonal, in
some sense, but as far as I can tell it's either impossible or nearly
impossible to reproduce the bug without this change.)
According to my testing, this seems to consistently improve codesize by
a small amount by forming bic more often for ISD::AND with an immediate.
Differential Revision: https://reviews.llvm.org/D50030
llvm-svn: 339472
Saves materializing the immediate for the "ands".
Corresponding patterns exist for lsrs+lsls, but that seems less common
in practice.
Now implemented as a DAGCombine.
Differential Revision: https://reviews.llvm.org/D49585
llvm-svn: 337945
The original code attempted to do this, but the std::abs() call didn't
actually do anything due to implicit type conversions. Fix the type
conversions, and perform the correct check for negative immediates.
This probably has very little practical impact, but it's worth fixing
just to avoid confusion in the future, I think.
Differential Revision: https://reviews.llvm.org/D48907
llvm-svn: 336742
This patch adds support for the q versions of the dup
(load-to-all-lanes) NEON intrinsics, such as vld2q_dup_f16() for
example.
Currently, non-q versions of the dup intrinsics are implemented
in clang by generating IR that first loads the elements of the
structure into the first lane with the lane (to-single-lane)
intrinsics, and then propagating it other lanes. There are at
least two problems with this approach. First, there are no
double-spaced to-single-lane byte-element instructions. For
example, there is no such instruction as 'vld2.8 { d0[0], d2[0]
}, [r0]'. That means we cannot rely on the to-single-lane
intrinsics and instructions to implement the q versions of the
dup intrinsics. Note that to-all-lanes instructions do support
all sizes of data items, including bytes.
The second problem with the current approach is that we need a
separate vdup instruction to propagate the structure to each
lane. So for vld4q_dup_f16() we would need four vdup instructions
in addition to the initial vld instruction.
This patch introduces dup LLVM intrinsics and reworks handling of
the currently supported (non-q) NEON dup intrinsics to expand
them into those LLVM intrinsics, thus eliminating the need for
using to-single-lane intrinsics and instructions.
Additionally, this patch adds support for u64 and s64 dup NEON
intrinsics. These are marked as Arch64-only in the ARM NEON
Reference, but it seems there are no reasons to not support them
in AArch32 mode. Please correct, if that is wrong.
That's what we generate with this patch applied:
vld2q_dup_f16:
vld2.16 {d0[], d2[]}, [r0]
vld2.16 {d1[], d3[]}, [r0]
vld3q_dup_f16:
vld3.16 {d0[], d2[], d4[]}, [r0]
vld3.16 {d1[], d3[], d5[]}, [r0]
vld4q_dup_f16:
vld4.16 {d0[], d2[], d4[], d6[]}, [r0]
vld4.16 {d1[], d3[], d5[], d7[]}, [r0]
Differential Revision: https://reviews.llvm.org/D48439
llvm-svn: 335733
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47447
llvm-svn: 334361
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47120
llvm-svn: 333825
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47121
llvm-svn: 333819
Summary: This code is now dead as the ARM backend uses ADDCARRY/SUBCARRY/SETCCCARRY .
Reviewers: rogfer01, efriedma, rengolin, javed.absar
Subscribers: kristof.beyls, chrib, llvm-commits
Differential Revision: https://reviews.llvm.org/D47413
llvm-svn: 333544
We've had Thumb1 support for ARMISD::SUBE for a while now, so this just
works. Reduces codesize a bit for 64-bit integer comparisons.
Differential Revision: https://reviews.llvm.org/D47387
llvm-svn: 333445
Chances are we'll be asked again after type legalization, but before that point
it's better to claim misaligned accesses aren't allowed than to assert.
llvm-svn: 332840
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
Summary: As per title. SETCCE is deprecated and will eventually be removed.
Reviewers: rogfer01, efriedma, rengolin, javed.absar
Subscribers: kristof.beyls, chrib, llvm-commits
Differential Revision: https://reviews.llvm.org/D46512
llvm-svn: 331929
By default LLVM thinks very large vectors get aligned to their size when
passed across functions. Unfortunately no-one told the ARM backend so it
doesn't trigger stack realignment and so accesses can cause the usual
misalignment issues (e.g. a data abort).
This changes the ABI alignment to the stack alignment, which in practice
(and as a bonus) also coincides with the alignment "natural" vectors get.
llvm-svn: 331451
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
This adds code generation support for the FP16 vmaxnm/vminnm scalar
instructions.
Differential Revision: https://reviews.llvm.org/D44675
llvm-svn: 330034
This is a follow up of rL327695 to instruction select more variants of VSELGT
and VSELGE, for which it is necessary to custom lower SELECT.
More work is required in this area, which will be addressed soon:
- more variants need to be regression tested, but this depends on the next point.
- first LowerConstantFP need to be adjusted for fp16 values.
Differential Revision: https://reviews.llvm.org/D45205
llvm-svn: 329788
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.
The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.
Differential Revision: https://reviews.llvm.org/D45017
llvm-svn: 328806
Follow up patch of r328313 to support the UseVMOVSR constraint. Removed
some unneeded instructions from the test and removed some stray
comments.
Differential Revision: https://reviews.llvm.org/D44941
llvm-svn: 328691
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)
llvm-svn: 328395
When targeting execute-only and fp-armv8, float constants in a compare
resulted in instruction selection failures. This is now fixed by using
vmov.f32 where possible, otherwise the floating point constant is
lowered into a integer constant that is moved into a floating point
register.
This patch also restores using fpcmp with immediate 0 under fp-armv8.
Change-Id: Ie87229706f4ed879a0c0cf66631b6047ed6c6443
llvm-svn: 328313
This extends the use of this attribute on ARM and AArch64 from
SVN r325900 (where it was only checked for fixed stack
allocations on ARM/AArch64, but for all stack allocations on X86).
This also adds a testcase for the existing use of disabling the
fixed stack probe with the attribute on ARM and AArch64.
Differential Revision: https://reviews.llvm.org/D44291
llvm-svn: 327897
This is the groundwork for adding the Armv8.2-A FP16 vector intrinsics, which
uses v4f16 and v8f16 vector operands and return values. All the moving parts
are tested with two intrinsics, a 1-operand v8f16 and a 2-operand v4f16
intrinsic. In a follow-up patch the rest of the intrinsics and tests will be
added.
Differential Revision: https://reviews.llvm.org/D44538
llvm-svn: 327839
This implements lowering of SELECT_CC for f16s, which enables
codegen of VSEL with f16 types.
Differential Revision: https://reviews.llvm.org/D44518
llvm-svn: 327695
Emulated TLS is enabled by llc flag -emulated-tls,
which is passed by clang driver.
When llc is called explicitly or from other drivers like LTO,
missing -emulated-tls flag would generate wrong TLS code for targets
that supports only this mode.
Now use useEmulatedTLS() instead of Options.EmulatedTLS to decide whether
emulated TLS code should be generated.
Unit tests are modified to run with and without the -emulated-tls flag.
Differential Revision: https://reviews.llvm.org/D42999
llvm-svn: 326341
Summary:
Expressions of the form x < 0 ? 0 : x; and x < -1 ? -1 : x can be lowered using bit-operations instead of branching or conditional moves
In thumb-mode this results in a two-instruction sequence, a shift followed by a bic or or while in ARM/thumb2 mode that has flexible second operand the shift can be folded into a single bic/or instructions. In most cases this results in smaller code and possibly less branches, and in no case larger than before.
Patch by Martin Svanfeldt
Reviewers: fhahn, pbarrio, rogfer01
Reviewed By: pbarrio, rogfer01
Subscribers: chrib, yroux, eugenis, efriedma, rogfer01, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42574
llvm-svn: 326333
Summary:
Add a target option AllowRegisterRenaming that is used to opt in to
post-register-allocation renaming of registers. This is set to 0 by
default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq
fields of all opcodes to be set to 1, causing
MachineOperand::isRenamable to always return false.
Set the AllowRegisterRenaming flag to 1 for all in-tree targets that
have lit tests that were effected by enabling COPY forwarding in
MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC,
RISCV, Sparc, SystemZ and X86).
Add some more comments describing the semantics of the
MachineOperand::isRenamable function and how it is set and maintained.
Change isRenamable to check the operand's opcode
hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of
relying on it being consistently reflected in the IsRenamable bit
setting.
Clear the IsRenamable bit when changing an operand's register value.
Remove target code that was clearing the IsRenamable bit when changing
registers/opcodes now that this is done conservatively by default.
Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in
one place covering all opcodes that have constant pipe read limit
restrictions.
Reviewers: qcolombet, MatzeB
Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D43042
llvm-svn: 325931
This patch combines some cases of ARMISD::CMOV for integers that arise in comparisons of the form
a != b ? x : 0
a == b ? 0 : x
and that currently (e.g. in Thumb1) are emitted as branches.
Differential Revision: https://reviews.llvm.org/D34515
llvm-svn: 325323
Summary:
In LLVM, 't' selects a floating-point/SIMD register and only supports
32-bit values. This is appropriately documented in the LLVM Language
Reference Manual. However, this behaviour diverges from that of GCC, where
't' selects the s0-s31 registers and its qX and dX variants depending on
additional operand modifiers (q/P).
For example, the following C code:
#include <arm_neon.h>
float32x4_t a, b, x;
asm("vadd.f32 %0, %1, %2" : "=t" (x) : "t" (a), "t" (b))
results in the following assembly if compiled with GCC:
vadd.f32 s0, s0, s1
whereas LLVM will show "error: couldn't allocate output register for
constraint 't'", since a, b, x are 128-bit variables, not 32-bit.
This patch extends the use of 't' to mean that of GCC, thus allowing
selection of the lower Q vector regs and their D/S variants. For example,
the earlier code will now compile as:
vadd.f32 q0, q0, q1
This behaviour still differs from that of GCC but I think it is actually
more correct, since LLVM picks up the right register type based on the
datatype of x, while GCC would need an extra operand modifier to achieve
the same result, as follows:
asm("vadd.f32 %q0, %q1, %q2" : "=t" (x) : "t" (a), "t" (b))
Since this is only an extension of functionality, existing code should not
be affected by this change. Note that operand modifiers q/P are already
supported by LLVM, so this patch should suffice to support inline
assembly with constraint 't' originally built for GCC.
Reviewers: grosbach, rengolin
Reviewed By: rengolin
Subscribers: rogfer01, efriedma, olista01, aemerson, javed.absar, eraman, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42962
llvm-svn: 325244
This adds most of the FP16 codegen support, but these areas need further work:
- FP16 literals and immediates are not properly supported yet (e.g. literal
pool needs work),
- Instructions that are generated from intrinsics (e.g. vabs) haven't been
added.
This will be addressed in follow-up patches.
Differential Revision: https://reviews.llvm.org/D42849
llvm-svn: 324321
Commit r323512 introduced an optimisation in LowerReturn for half-precision
return values. A missing check caused a crash when the return value is "undef"
(i.e. a node that has no operands).
Differential Revision: https://reviews.llvm.org/D42743
llvm-svn: 323968
Summary:
Expressions of the form x < 0 ? 0 : x; and x < -1 ? -1 : x can be lowered using bit-operations instead of branching or conditional moves
In thumb-mode this results in a two-instruction sequence, a shift followed by a bic or or while in ARM/thumb2 mode that has flexible second operand the shift can be folded into a single bic/or instructions. In most cases this results in smaller code and possibly less branches, and in no case larger than before.
Patch by Marten Svanfeldt.
Reviewers: fhahn, pbarrio
Reviewed By: pbarrio
Subscribers: efriedma, rogfer01, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42574
llvm-svn: 323869
Half-precision arguments and return values are passed as if it were an int or
float for ARM. This results in truncates and bitcasts to/from i16 and f16
values, which are legalized very early to stack stores/loads. When FullFP16 is
enabled, we want to avoid codegen for these bitcasts as it is unnecessary and
inefficient.
Differential Revision: https://reviews.llvm.org/D42580
llvm-svn: 323861
This is the groundwork for Armv8.2-A FP16 code generation .
Clang passes and returns _Float16 values as floats, together with the required
bitconverts and truncs etc. to implement correct AAPCS behaviour, see D42318.
We will implement half-precision argument passing/returning lowering in the ARM
backend soon, but for now this means that this:
_Float16 sub(_Float16 a, _Float16 b) {
return a + b;
}
gets lowered to this:
define float @sub(float %a.coerce, float %b.coerce) {
entry:
%0 = bitcast float %a.coerce to i32
%tmp.0.extract.trunc = trunc i32 %0 to i16
%1 = bitcast i16 %tmp.0.extract.trunc to half
<SNIP>
%add = fadd half %1, %3
<SNIP>
}
When FullFP16 is *not* supported, we don't make f16 a legal type, and we get
legalization for "free", i.e. nothing changes and everything works as before.
And also f16 argument passing/returning is handled.
When FullFP16 is supported, we do make f16 a legal type, and have 2 places that
we need to patch up: f16 argument passing and returning, which involves minor
tweaks to avoid unnecessary code generation for some bitcasts.
As a "demonstrator" that this works for the different FP16, FullFP16, softfp
modes, etc., I've added match rules to the VSUB instruction description showing
that we can codegen this instruction from IR, but more importantly, also to
some conversion instructions. These conversions were causing issue before in
the FP16 and FullFP16 cases.
I've also added match rules to the VLDRH and VSTRH desriptions, so that we can
actually compile the entire half-precision sub code example above. This showed
that these loads and stores had the wrong addressing mode specified: AddrMode5
instead of AddrMode5FP16, which turned out not be implemented at all, so that
has also been added.
This is the minimal patch that shows all the different moving parts. In patch
2/3 I will add some efficient lowering of bitcasts, and in 2/3 I will add the
remaining Armv8.2-A FP16 instruction descriptions.
Thanks to Sam Parker and Oliver Stannard for their help and reviews!
Differential Revision: https://reviews.llvm.org/D38315
llvm-svn: 323512
Summary: For long shifts, the inlined version takes about 20 instructions on Thumb1. To avoid the code bloat, expand to __aeabi_ calls if target is Thumb1.
Reviewers: samparker
Reviewed By: samparker
Subscribers: samparker, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42401
llvm-svn: 323354
This matches what MSVC does for alloca() function calls on ARM.
Even if MSVC doesn't support VLAs at the language level, it does
support the alloca function.
On the clang level, both the _alloca() (when emulating MSVC, which is
what the alloca() function expands to) and __builtin_alloca() builtin
functions, and VLAs, map to the same LLVM IR "alloca" function - so
within LLVM they're not distinguishable from each other.
Differential Revision: https://reviews.llvm.org/D42292
llvm-svn: 323308
This extends my previous patches to also optimize overflow-checked multiplies during SelectionDAG.
Differential revision: https://reviews.llvm.org/D40922
llvm-svn: 322738
This patch teaches the Arm back-end to generate the SMMULR, SMMLAR and SMMLSR
instructions from equivalent IR patterns.
Differential Revision: https://reviews.llvm.org/D41775
llvm-svn: 322361
The AArch64 backend contains code to optimize {s,u}{add,sub}.with.overflow during SelectionDAG. This commit ports that code to the ARM backend.
Differential revision: https://reviews.llvm.org/D35635
llvm-svn: 321224
Summary:
Implement lower of unsigned saturation on an interval [0, k] where k + 1 is a power of two using USAT instruction in a similar way to how [~k, k] is lowered using SSAT on ARM models that supports it.
Patch by Marten Svanfeldt
Reviewers: t.p.northover, pbarrio, eastig, SjoerdMeijer, javed.absar, fhahn
Reviewed By: fhahn
Subscribers: fhahn, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D41348
llvm-svn: 321164
Note:
- X86ISelLowering: setLibcallName(SINCOS) was superfluous as
InitLibcalls() already does it.
- ARMISelLowering: Setting libcallnames for sincos/sincosf seemed
superfluous as in the darwin case it wouldn't be used while for all
other cases InitLibcalls already does it.
llvm-svn: 321036
Rather than adding more bits to express every
MMO flag you could want, just directly use the
MMO flags. Also fixes using a bunch of bool arguments to
getMemIntrinsicNode.
On AMDGPU, buffer and image intrinsics should always
have MODereferencable set, but currently there is no
way to do that directly during the initial intrinsic
lowering.
llvm-svn: 320746
Summary:
Add isRenamable() predicate to MachineOperand. This predicate can be
used by machine passes after register allocation to determine whether it
is safe to rename a given register operand. Register operands that
aren't marked as renamable may be required to be assigned their current
register to satisfy constraints that are not captured by the machine
IR (e.g. ABI or ISA constraints).
Reviewers: qcolombet, MatzeB, hfinkel
Subscribers: nemanjai, mcrosier, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D39400
llvm-svn: 320503
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
- fixes PR35103
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 320355
Summary:
The compiler fails with the following error message:
fatal error: error in backend: ran out of registers during
register allocation
Tail call optimization for Armv8-M.base fails to meet all the required
constraints when handling calls to function pointers where the
arguments take up r0-r3. This is because the pointer to the
function to be called can only be stored in r0-r3, but these are
all occupied by arguments. This patch makes sure that tail call
optimization does not try to handle this type of calls.
Reviewers: chill, MatzeB, olista01, rengolin, efriedma
Reviewed By: olista01, efriedma
Subscribers: efriedma, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D40706
llvm-svn: 319664
This matches how it is done on X86.
This allows using emulated tls on windows; in MinGW environments,
native tls isn't supported at the moment.
Differential Revision: https://reviews.llvm.org/D40769
llvm-svn: 319643
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
't' constraint normally only accepts f32 operands, but for VCVT the
operands can be i32. LLVM is overly restrictive and rejects asm like:
float foo() {
float result;
__asm__ __volatile__(
"vcvt.f32.s32 %[result], %[arg1]\n"
: [result]"=t"(result)
: [arg1]"t"(0x01020304) );
return result;
}
Relax the value type for 't' constraint to either f32 or i32.
Differential Revision: https://reviews.llvm.org/D40137
llvm-svn: 318472
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D39871
llvm-svn: 318081
When generating table jump code for switch statements, place the jump
table label as the first operand in the various addition instructions
in order to enable addressing mode selectors to better match index
computation and possibly fold them into the addressing mode of the
table entry load instruction.
Differential revision: https://reviews.llvm.org/D39752
llvm-svn: 318033
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
The generic dag combiner will fold:
(shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)
(shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)
This can create constants which are too large to use as an immediate.
Many ALU operations are also able of performing the shl, so we can
unfold the transformation to prevent a mov imm instruction from being
generated.
Other patterns, such as b + ((a << 1) | 510), can also be simplified
in the same manner.
Differential Revision: https://reviews.llvm.org/D38084
llvm-svn: 317197
As far as I can tell, this matches gcc: -mfloat-abi determines the
calling convention for all functions except those explicitly defined as
soft-float in the ARM RTABI.
This change only affects cases where the user specifies -mfloat-abi to
override the default calling convention derived from the target triple.
Fixes https://bugs.llvm.org//show_bug.cgi?id=34530.
Differential Revision: https://reviews.llvm.org/D38299
llvm-svn: 316708
Swap the compare operands if the lhs is a shift and the rhs isn't,
as in arm and T2 the shift can be performed by the compare for its
second operand.
Differential Revision: https://reviews.llvm.org/D39004
llvm-svn: 316562
This adds some more debug messages to the type legalizer and functions
like PromoteNode, ExpandNode, ExpandLibCall in an attempt to make
the debug messages a little bit more informative and useful.
Differential Revision: https://reviews.llvm.org/D38450
llvm-svn: 314773
I implemented isTruncateFree in rL313533, this patch fixes the logic
to match my comment, as the previous logic was too general. Now the
only truncates that are free are i64 -> i32.
Differential Revision: https://reviews.llvm.org/D38234
llvm-svn: 314280
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313618
Implement the isTruncateFree hooks, lifted from AArch64, that are
used by TargetTransformInfo. This allows simplifycfg to reduce the
test case into a single basic block.
Differential Revision: https://reviews.llvm.org/D37516
llvm-svn: 313533
This was causing PR34045 to fire again.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
Also revert follow-up r313010:
> [ARM] Fix typo when creating ISD::SUB nodes
>
> In D35192, I accidentally introduced a typo when creating ISD::SUB nodes,
> giving them two values instead of one.
>
> This fails when the merge_values combiner finds one of these nodes.
>
> This change fixes PR34564.
>
> Differential Revision: https://reviews.llvm.org/D37690
llvm-svn: 313044
In D35192, I accidentally introduced a typo when creating ISD::SUB nodes,
giving them two values instead of one.
This fails when the merge_values combiner finds one of these nodes.
This change fixes PR34564.
Differential Revision: https://reviews.llvm.org/D37690
llvm-svn: 313010
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313009
It caused PR34564.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312980
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312898
ARMTargetLowering::isLegalAddressingMode can accept illegal addressing modes
for the Thumb1 target. This causes generation of redundant code and affects
performance.
This fixes PR34106: https://bugs.llvm.org/show_bug.cgi?id=34106
Differential Revision: https://reviews.llvm.org/D36467
llvm-svn: 311649
The ARM backend should call setBooleanContents so that it can
use known bits to make some optimizations.
Review: D35821
Patch by Joel Galenson <jgalenson@google.com>
llvm-svn: 311446
The calling convention can be specified by the user in IR. Failing to support
a particular calling convention isn't a programming error, and so relying on
llvm_unreachable to catch and report an unsupported calling convention is not
appropriate.
Differential Revision: https://reviews.llvm.org/D36830
llvm-svn: 311435
This is the exact same fix as in SVN r247254. In that commit, the fix was
applied only for isVTRNMask and isVTRN_v_undef_Mask, but the same issue
is present for VZIP/VUZP as well.
This fixes PR33921.
Differential Revision: https://reviews.llvm.org/D36899
llvm-svn: 311258
When lowering a VLA, we emit a __chstk call. However, this call can
internally clobber CPSR. We did not mark this register as an ImpDef,
which could potentially allow a comparison to be hoisted above the call
to `__chkstk`. In such a case, the CPSR could be clobbered, and the
check invalidated. When the support was initially added, it seemed that
the call would take care of preventing CPSR from being clobbered, but
this is not the case. Mark the register as clobbered to fix a possible
state corruption.
llvm-svn: 311061
Summary:
Without the SrcVT its hard to know what is really being asked for. For example if your target has 128, 256, and 512 bit vectors. Maybe extracting 128 from 256 is cheap, but maybe extracting 128 from 512 is not.
For x86 we do support extracting a quarter of a 512-bit register. But for i1 vectors we don't have isel patterns for extracting arbitrary pieces. So we need this to have a correct implementation of isExtractSubvectorCheap for mask vectors.
Reviewers: RKSimon, zvi, efriedma
Reviewed By: RKSimon
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D36649
llvm-svn: 310793
The existing code is very clever, but not clear, which seems
like the wrong tradeoff here.
Differential Revision: https://reviews.llvm.org/D36559
llvm-svn: 310653
This patch:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) <- (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) <- (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRY into ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) -> C
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 309923
IMHO it is an antipattern to have a enum value that is Default.
At any given piece of code it is not clear if we have to handle
Default or if has already been mapped to a concrete value. In this
case in particular, only the target can do the mapping and it is nice
to make sure it is always done.
This deletes the two default enum values of CodeModel and uses an
explicit Optional<CodeModel> when it is possible that it is
unspecified.
llvm-svn: 309911
Changing mask argument type from const SmallVectorImpl<int>& to
ArrayRef<int>.
This came up in D35700 where a mask is received as an ArrayRef<int> and
we want to pass it to TargetLowering::isShuffleMaskLegal().
Also saves a few lines of code.
llvm-svn: 309085
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.
In order to achieve this, the following common code changes were made:
* New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
LSR should do instruction-based addressing evaluations by calling
isLegalAddressingMode() with the Instruction pointers.
* In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
not just loads or stores.
SystemZ changes:
* isLSRCostLess() implemented with Insns first, and without ImmCost.
* New function supportedAddressingMode() that is a helper for TTI methods
looking at Instructions passed via pointers.
Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262https://reviews.llvm.org/D35049
llvm-svn: 308729
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
Alexander Timofeev