This is a follow-on from the discussion in http://reviews.llvm.org/D12154.
This change allows memset/memcpy to use SSE or AVX memory accesses for any chip that has
generally fast unaligned memory ops.
A motivating use case for this change is a clang invocation that doesn't explicitly set
the CPU, but does target a feature that we know only exists on a CPU that supports fast
unaligned memops. For example:
$ clang -O1 foo.c -mavx
This resolves a difference in lowering noted in PR24449:
https://llvm.org/bugs/show_bug.cgi?id=24449
Before this patch, we used different store types depending on whether the example can be
lowered as a memset or not.
Differential Revision: http://reviews.llvm.org/D12288
llvm-svn: 245950
This fixes two issues in x86 fptoui lowering.
1) Makes conversions from f80 go through the right path on AVX-512.
2) Implements an inline sequence for fptoui i64 instead of a library
call. This improves performance by 6X on SSE3+ and 3X otherwise.
Incidentally, it also removes the use of ftol2 for fptoui, which was
wrong to begin with, as ftol2 converts to a signed i64, producing
wrong results for values >= 2^63.
Patch by: mitch.l.bodart@intel.com
Differential Revision: http://reviews.llvm.org/D11316
llvm-svn: 245924
See discussion in D12154 ( http://reviews.llvm.org/D12154 ), AMD Software
Optimization Guides for 10H/12H/15H/16H, and Agner Fog's experimental data.
llvm-svn: 245733
This will confirm that the patch in D12154 is actually NFC.
It will also confirm that the proposed changes for the AMD chips
are behaving as expected.
llvm-svn: 245704
Fixes PR23464: one way to use the broadcast intrinsics is:
_mm256_broadcastw_epi16(_mm_cvtsi32_si128(*(int*)src));
We don't currently fold this, but now that we use native IR for
the intrinsics (r245605), we can look through one bitcast to find
the broadcast scalar.
Differential Revision: http://reviews.llvm.org/D10557
llvm-svn: 245613
Since r245605, the clang headers don't use these anymore.
r245165 updated some of the tests already; update the others, add
an autoupgrade, remove the intrinsics, and cleanup the definitions.
Differential Revision: http://reviews.llvm.org/D10555
llvm-svn: 245606
We still need to add constant folding of vector comparisons to fold the tests for targets that don't support the respective min/max nodes
I needed to update 2011-12-06-AVXVectorExtractCombine to load a vector instead of using a constant vector to prevent it folding
Differential Revision: http://reviews.llvm.org/D12118
llvm-svn: 245503
We don't do a great job with >= 0 comparisons against zero when the
result is used as an i8.
Given something like:
void f(long long LL, bool *B) {
*B = LL >= 0;
}
We used to generate:
shrq $63, %rdi
xorb $1, %dil
movb %dil, (%rsi)
Now we generate:
testq %rdi, %rdi
setns (%rsi)
Differential Revision: http://reviews.llvm.org/D12136
llvm-svn: 245498
Check to see if this is a CONCAT_VECTORS of a bunch of EXTRACT_SUBVECTOR operations. If so, and if the EXTRACT_SUBVECTOR vector inputs come from at most two distinct vectors the same size as the result, attempt to turn this into a legal shuffle.
Differential Revision: http://reviews.llvm.org/D12125
llvm-svn: 245490
Reintroduce r245442. Remove an overly conservative assertion introduced
in r245442. We could replace the assertion to use `shareSameRegisterFile`
instead, but in that point in `insertPHI` we already lost the original
Def subreg to check against. So drop the assertion completely.
Original commit message:
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 245479
This patch updates the X86 lowering so that the Exception Pointer and Selector
are 64-bit wide only if Subtarget.isTarget64BitLP64.
Patch by João Porto
Reviewers: dschuff, rnk
Differential Revision: http://reviews.llvm.org/D12111
llvm-svn: 245454
Reapply r243486.
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 245442
There are some cases where the mul sequence is smaller, but for the most part,
using a div is preferable. This does not apply to vectors, since x86 doesn't
have vector idiv, and a vector mul/shifts sequence ought to be smaller than a
scalarized division.
Differential Revision: http://reviews.llvm.org/D12082
llvm-svn: 245431
We can set additional bits in a mask given that we know the other
operand of an AND already has some bits set to zero. This can be more
efficient if doing so allows us to use an instruction which implicitly
sign extends the immediate.
This fixes PR24085.
Differential Revision: http://reviews.llvm.org/D11289
llvm-svn: 245169
For cases where we TRUNCATE and then ZERO_EXTEND to a larger size (often from vector legalization), see if we can mask the source data and then ZERO_EXTEND (instead of after a ANY_EXTEND). This can help avoid having to generate a larger mask, and possibly applying it to several sub-vectors.
(zext (truncate x)) -> (zext (and(x, m))
Includes a minor patch to SystemZ to better recognise 8/16-bit zero extension patterns from RISBG bit-extraction code.
This is the first of a number of minor patches to help improve the conversion of byte masks to clear mask shuffles.
Differential Revision: http://reviews.llvm.org/D11764
llvm-svn: 245160
Although targeting CoreCLR is similar to targeting MSVC, there are
certain important differences that the backend must be aware of
(e.g. differences in stack probes, EH, and library calls).
Differential Revision: http://reviews.llvm.org/D11012
llvm-svn: 245115
This patch fixes the x86 implementation of allowsMisalignedMemoryAccess() to correctly
return the 'Fast' output parameter for 32-byte accesses. To test that, an existing load
merging optimization is changed to use the TLI hook. This exposes a shortcoming in the
current logic and results in the regression test update. Changing other direct users of
the isUnalignedMem32Slow() x86 CPU attribute would be a follow-on patch.
Without the fix in allowsMisalignedMemoryAccesses(), we will infinite loop when targeting
SandyBridge because LowerINSERT_SUBVECTOR() creates 32-byte loads from two 16-byte loads
while PerformLOADCombine() splits them back into 16-byte loads.
Differential Revision: http://reviews.llvm.org/D10662
llvm-svn: 245075
This reverts commit r245047.
It was failing on the darwin bots. The problem was that when running
./bin/llc -march=msp430
llc gets to
if (TheTriple.getTriple().empty())
TheTriple.setTriple(sys::getDefaultTargetTriple());
Which means that we go with an arch of msp430 but a triple of
x86_64-apple-darwin14.4.0 which fails badly.
That code has to be updated to select a triple based on the value of
march, but that is not a trivial fix.
llvm-svn: 245062
Other than some places that were handling unknown as ELF, this should
have no change. The test updates are because we were detecting
arm-coff or x86_64-win64-coff as ELF targets before.
It is not clear if the enum should live on the Triple. At least now it lives
in a single location and should be easier to move somewhere else.
llvm-svn: 245047
This commit modifies the way the machine basic blocks are serialized - now the
machine basic blocks are serialized using a custom syntax instead of relying on
YAML primitives. Instead of using YAML mappings to represent the individual
machine basic blocks in a machine function's body, the new syntax uses a single
YAML block scalar which contains all of the machine basic blocks and
instructions for that function.
This is an example of a function's body that uses the old syntax:
body:
- id: 0
name: entry
instructions:
- '%eax = MOV32r0 implicit-def %eflags'
- 'RETQ %eax'
...
The same body is now written like this:
body: |
bb.0.entry:
%eax = MOV32r0 implicit-def %eflags
RETQ %eax
...
This syntax change is motivated by the fact that the bundled machine
instructions didn't map that well to the old syntax which was using a single
YAML sequence to store all of the machine instructions in a block. The bundled
machine instructions internally use flags like BundledPred and BundledSucc to
determine the bundles, and serializing them as MI flags using the old syntax
would have had a negative impact on the readability and the ease of editing
for MIR files. The new syntax allows me to serialize the bundled machine
instructions using a block construct without relying on the internal flags,
for example:
BUNDLE implicit-def dead %itstate, implicit-def %s1 ... {
t2IT 1, 24, implicit-def %itstate
%s1 = VMOVS killed %s0, 1, killed %cpsr, implicit killed %itstate
}
This commit also converts the MIR testcases to the new syntax. I developed
a script that can convert from the old syntax to the new one. I will post the
script on the llvm-commits mailing list in the thread for this commit.
llvm-svn: 244982
This abstracts away the test for "when can we fold across a MachineInstruction"
into the the MI interface, and changes call-frame optimization use the same test
the peephole optimizer users.
Differential Revision: http://reviews.llvm.org/D11945
llvm-svn: 244729
As discussed in D11886, this patch moves the SSE/AVX vector blend folding to instcombiner from PerformINTRINSIC_WO_CHAINCombine (which allows us to remove this completely).
InstCombiner already had partial support for this, I just had to add support for zero (ConstantAggregateZero) masks and also the case where both selection inputs were the same (allowing us to ignore the mask).
I also moved all the relevant combine tests into InstCombine/blend_x86.ll
Differential Revision: http://reviews.llvm.org/D11934
llvm-svn: 244723
First step in preventing immediates that occur more than once within a single
basic block from being pulled into their users, in order to prevent unnecessary
large instruction encoding .Currently enabled only when optimizing for size.
Patch by: zia.ansari@intel.com
Differential Revision: http://reviews.llvm.org/D11363
llvm-svn: 244601
When optimizing for size, replace "addl $4, %esp" and "addl $8, %esp"
following a call by one or two pops, respectively. We don't try to do it in
general, but only when the stack adjustment immediately follows a call - which
is the most common case.
That allows taking a short-cut when trying to find a free register to pop into,
instead of a full-blown liveness check. If the adjustment immediately follows a
call, then every register the call clobbers but doesn't define should be dead at
that point, and can be used.
Differential Revision: http://reviews.llvm.org/D11749
llvm-svn: 244578
The condition for clearing the folding candidate list was clamped together
with the "uninteresting instruction" condition. This is too conservative,
e.g. we don't need to clear the list when encountering an IMPLICIT_DEF.
Differential Revision: http://reviews.llvm.org/D11591
llvm-svn: 244577
The PATCHPOINT instructions have a single optional defined register operand,
but the machine verifier can't verify the optional defined register operands.
This commit makes sure that the machine verifier won't report an error when a
PATCHPOINT instruction doesn't have its optional defined register operand.
This change will allow us to enable the machine verifier for the code
generation tests for the patchpoint intrinsics.
Reviewers: Juergen Ributzka
llvm-svn: 244513
frame setup instruction.
This commit ensures that the stack map lowering code in FastISel adds an
appropriate number of immediate operands to the frame setup instruction.
The previous code added just one immediate operand, which was fine for a target
like AArch64, but on X86 the ADJCALLSTACKDOWN64 instruction needs two explicit
operands. This caused the machine verifier to report an error when the old code
added just one.
Reviewers: Juergen Ributzka
Differential Revision: http://reviews.llvm.org/D11853
llvm-svn: 244508
NaCl's sandbox doesn't allow PUSHF/POPF out of security concerns (priviledged emulators have forgotten to mask system bits in the past, and EFLAGS's DF bit is a constant source of hilarity). Commit r220529 fixed PR20376 by saving cmpxchg's flags result using EFLAGS, this commit now generated LAHF/SAHF instead, for all of x86 (not just NaCl) because it leads to an overall performance gain over PUSHF/POPF.
As with the previous patch this code generation is pretty bad because it occurs very later, after register allocation, and in many cases it rematerializes flags which were already available (e.g. already in a register through SETE). Fortunately it's somewhat rare that this code needs to fire.
I did [[ https://github.com/jfbastien/benchmark-x86-flags | a bit of benchmarking ]], the results on an Intel Haswell E5-2690 CPU at 2.9GHz are:
| Time per call (ms) | Runtime (ms) | Benchmark |
| 0.000012514 | 6257 | sete.i386 |
| 0.000012810 | 6405 | sete.i386-fast |
| 0.000010456 | 5228 | sete.x86-64 |
| 0.000010496 | 5248 | sete.x86-64-fast |
| 0.000012906 | 6453 | lahf-sahf.i386 |
| 0.000013236 | 6618 | lahf-sahf.i386-fast |
| 0.000010580 | 5290 | lahf-sahf.x86-64 |
| 0.000010304 | 5152 | lahf-sahf.x86-64-fast |
| 0.000028056 | 14028 | pushf-popf.i386 |
| 0.000027160 | 13580 | pushf-popf.i386-fast |
| 0.000023810 | 11905 | pushf-popf.x86-64 |
| 0.000026468 | 13234 | pushf-popf.x86-64-fast |
Clearly `PUSHF`/`POPF` are suboptimal. It doesn't really seems to be worth teaching LLVM about individual flags, at least not for this purpose.
Reviewers: rnk, jvoung, t.p.northover
Subscribers: llvm-commits
Differential revision: http://reviews.llvm.org/D6629
llvm-svn: 244503
As discussed in D11760, this patch moves the (V)PSRA(WD) arithmetic shift-by-constant folding to InstCombine to match the logical shift implementations.
Differential Revision: http://reviews.llvm.org/D11886
llvm-svn: 244495
I looked into adding a warning / error for this to FileCheck, but there doesn't
seem to be a good way to avoid it triggering on the instances of it in RUN lines.
llvm-svn: 244481
PR24139 contains an analysis of poor register allocation. One of the findings
was that when calculating the spill weight, a rematerializable interval once
split is no longer rematerializable. This is because the isRematerializable
check in CalcSpillWeights.cpp does not follow the copies introduced by live
range splitting (after splitting, the live interval register definition is a
copy which is not rematerializable).
Reviewers: qcolombet
Differential Revision: http://reviews.llvm.org/D11686
llvm-svn: 244439
points.
There is an infinite loop that can occur in Shrink Wrapping while searching
for the Save/Restore points.
Part of this search checks whether the save/restore points are located in
different loop nests and if so, uses the (post) dominator trees to find the
immediate (post) dominator blocks. However, if the current block does not have
any immediate (post) dominators then this search will result in an infinite
loop. This can occur in code containing an infinite loop.
The modification checks whether the immediate (post) dominator is different from
the current save/restore block. If it is not, then the search terminates and the
current location is not considered as a valid save/restore point for shrink wrapping.
Phabricator: http://reviews.llvm.org/D11607
llvm-svn: 244247
This change improves EmitLoweredSelect() so that multiple contiguous CMOV pseudo
instructions with the same (or exactly opposite) conditions get lowered using a single
new basic-block. This eliminates unnecessary extra basic-blocks (and CFG merge points)
when contiguous CMOVs are being lowered.
Patch by: kevin.b.smith@intel.com
Differential Revision: http://reviews.llvm.org/D11428
llvm-svn: 244202
Summary: PR24191 finds that the expected memory-register operations aren't generated when relaxed { load ; modify ; store } is used. This is similar to PR17281 which was addressed in D4796, but only for memory-immediate operations (and for memory orderings up to acquire and release). This patch also handles some floating-point operations.
Reviewers: reames, kcc, dvyukov, nadav, morisset, chandlerc, t.p.northover, pete
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11382
llvm-svn: 244128
In the commentary for D11660, I wasn't sure if it was alright to create new
integer machine instructions without also creating the implicit EFLAGS operand.
From what I can see, the implicit operand is always created by the MachineInstrBuilder
based on the instruction type, so we don't have to do that explicitly. However, in
reviewing the debug output, I noticed that the operand was not marked as 'dead'.
The machine combiner should do that to preserve future optimization opportunities
that may be checking for that dead EFLAGS operand themselves.
Differential Revision: http://reviews.llvm.org/D11696
llvm-svn: 243990
Since r241097, `DIBuilder` has only created distinct `DICompileUnit`s.
The backend is liable to start relying on that (if it hasn't already),
so make uniquable `DICompileUnit`s illegal and automatically upgrade old
bitcode. This is a nice cleanup, since we can remove an unnecessary
`DenseSet` (and the associated uniquing info) from `LLVMContextImpl`.
Almost all the testcases were updated with this script:
git grep -e '= !DICompileUnit' -l -- test |
grep -v test/Bitcode |
xargs sed -i '' -e 's,= !DICompileUnit,= distinct !DICompileUnit,'
I imagine something similar should work for out-of-tree testcases.
llvm-svn: 243885
The XformToShuffleWithZero method currently checks AND masks at the per-lane level for all-one and all-zero constants and attempts to convert them to legal shuffle clear masks.
This patch generalises XformToShuffleWithZero, splitting and checking the sub-lanes of the constants down to the byte level to see if any legal shuffle clear masks are possible. This allows a lot of masks (often from legalization or truncation) to be folded into existing shuffle patterns and removes a lot of constant mask loading.
There are a few examples of poor shuffle lowering that are exposed by this patch that will be cleaned up in future patches (e.g. merging shuffles that are separated by bitcasts, x86 legalized v8i8 zero extension uses PMOVZX+AND+AND instead of AND+PMOVZX, etc.)
Differential Revision: http://reviews.llvm.org/D11518
llvm-svn: 243831
Remove the fake `DW_TAG_auto_variable` and `DW_TAG_arg_variable` tags,
using `DW_TAG_variable` in their place Stop exposing the `tag:` field at
all in the assembly format for `DILocalVariable`.
Most of the testcase updates were generated by the following sed script:
find test/ -name "*.ll" -o -name "*.mir" |
xargs grep -l 'DILocalVariable' |
xargs sed -i '' \
-e 's/tag: DW_TAG_arg_variable, //' \
-e 's/tag: DW_TAG_auto_variable, //'
There were only a handful of tests in `test/Assembly` that I needed to
update by hand.
(Note: a follow-up could change `DILocalVariable::DILocalVariable()` to
set the tag to `DW_TAG_formal_parameter` instead of `DW_TAG_variable`
(as appropriate), instead of having that logic magically in the backend
in `DbgVariable`. I've added a FIXME to that effect.)
llvm-svn: 243774
Add i16, i32, i64 imul machine instructions to the list of reassociation
candidates.
A new bit of logic is needed to handle integer instructions: they have an
implicit EFLAGS operand, so we have to make sure it's dead in order to do
any reassociation with integer ops.
Differential Revision: http://reviews.llvm.org/D11660
llvm-svn: 243756
Fixing MinSize attribute handling was discussed in D11363.
This is a prerequisite patch to doing that.
The handling of OptSize when lowering mem* functions was broken
on Darwin because it wants to ignore -Os for these cases, but the
existing logic also made it ignore -Oz (MinSize).
The Linux change demonstrates a widespread problem. The backend
doesn't usually recognize the MinSize attribute by itself; it
assumes that if the MinSize attribute exists, then the OptSize
attribute must also exist.
Fixing this more generally will be a follow-on patch or two.
Differential Revision: http://reviews.llvm.org/D11568
llvm-svn: 243693
Bonus change to remove emacs major mode marker from SystemZMachineFunctionInfo.cpp because emacs already knows it's C++ from the extension. Also fix typo "appeary" in AMDGPUMCAsmInfo.h.
llvm-svn: 243585
This patch improves the 32-bit target i64 constant matching to detect the shuffle vector splats that are introduced by i64 vector shift vectorization (D8416).
Differential Revision: http://reviews.llvm.org/D11327
llvm-svn: 243577
This patch vectorizes the v2i64/v4i64 ASHR shift operations - the last remaining integer vector shifts that are still being transferred to/from the scalar unit to be completed.
Differential Revision: http://reviews.llvm.org/D11439
llvm-svn: 243569
PR24141: https://llvm.org/bugs/show_bug.cgi?id=24141
contains a test case where we have duplicate entries in a node's uses() list.
After r241826, we use CombineTo() to delete dead nodes when combining the uses into
reciprocal multiplies, but this fails if we encounter the just-deleted node again in
the list.
The solution in this patch is to not add duplicate entries to the list of users that
we will subsequently iterate over. For the test case, this avoids triggering the
combine divisors logic entirely because there really is only one user of the divisor.
Differential Revision: http://reviews.llvm.org/D11345
llvm-svn: 243500
Reapply 243271 with more fixes; although we are not handling multiple
sources with coalescable copies, we were not properly skipping this
case.
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 243486
GR64 <-> VR64 copies).
This commit adds a MIR test case for the commit r242191, which was committed
without one. This test case verifies that the ExpandPostRA pass expands the
GR64 <-> VR64 copies into the appropriate MMX_MOV instructions.
llvm-svn: 243457
The 'common' section TLS is not implemented.
Current C/C++ TLS variables are not placed in common section.
DWARF debug info to get the address of TLS variables is not generated yet.
clang and driver changes in http://reviews.llvm.org/D10524
Added -femulated-tls flag to select the emulated TLS model,
which will be used for old targets like Android that do not
support ELF TLS models.
Added TargetLowering::LowerToTLSEmulatedModel as a target-independent
function to convert a SDNode of TLS variable address to a function call
to __emutls_get_address.
Added into lib/Target/*/*ISelLowering.cpp to call LowerToTLSEmulatedModel
for TLSModel::Emulated. Although all targets supporting ELF TLS models are
enhanced, emulated TLS model has been tested only for Android ELF targets.
Modified AsmPrinter.cpp to print the emutls_v.* and emutls_t.* variables for
emulated TLS variables.
Modified DwarfCompileUnit.cpp to skip some DIE for emulated TLS variabls.
TODO: Add proper DIE for emulated TLS variables.
Added new unit tests with emulated TLS.
Differential Revision: http://reviews.llvm.org/D10522
llvm-svn: 243438
VPAND is a lot faster than VPSHUFB and VPBLENDVB - this patch ensures we attempt to lower to a basic bitmask before lowering to the slower byte shuffle/blend instructions.
Split off from D11518.
Differential Revision: http://reviews.llvm.org/D11541
llvm-svn: 243395
This is a follow-up to the FIXME that was added with D7474 ( http://reviews.llvm.org/rL229531 ).
I thought this load folding bug had been made hard-to-hit, but it turns out to be very easy
when targeting 32-bit x86 and causes a miscompile/crash in Wine:
https://bugs.winehq.org/show_bug.cgi?id=38826https://llvm.org/bugs/show_bug.cgi?id=22371#c25
The quick fix is to simply remove the scalar FP logical instructions from the load folding table
in X86InstrInfo, but that causes us to miss load folds that should be possible when lowering fabs,
fneg, fcopysign. So the majority of this patch is altering those lowerings to use *vector* FP
logical instructions (because that's all x86 gives us anyway). That lets us do the load folding
legally.
Differential Revision: http://reviews.llvm.org/D11477
llvm-svn: 243361
This commit zeroes out the virtual register references in the machine
function's liveins in the class 'MachineRegisterInfo' when the virtual
register definitions are cleared.
Reviewers: Matthias Braun
llvm-svn: 243290
Reapply r242295 with fixes in the implementation.
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 243271
Add a verifier check that `DILocalVariable`s of tag
`DW_TAG_arg_variable` always have a non-zero 'arg:' field, and those of
tag `DW_TAG_auto_variable` always have a zero 'arg:' field. These are
the only configurations that are properly understood by the backend.
(Also, fix the bad examples in LangRef and test/Assembler, and fix the
bug in Kaleidoscope Ch8.)
A large number of testcases seem to have bitrotted their way forward
from some ancient version of the debug info hierarchy that didn't have
`arg:` parameters. If you have out-of-tree testcases that start failing
in the verifier and you don't care enough to get the `arg:` right, you
may have some luck just calling:
sed -e 's/, arg: 0/, arg: 1/'
or some such, but I hand-updated the ones in tree.
llvm-svn: 243183
The test in PR24199 ( https://llvm.org/bugs/show_bug.cgi?id=24199 ) crashes because machine
trace metrics was not ignoring dbg_value instructions when calculating data dependencies.
The machine-combiner pass asks machine trace metrics to calculate an instruction trace,
does some reassociations, and calls MachineInstr::eraseFromParentAndMarkDBGValuesForRemoval()
along with MachineTraceMetrics::invalidate(). The dbg_value instructions have their operands
invalidated, but the instructions are not expected to be deleted.
On a subsequent loop iteration of the machine-combiner pass, machine trace metrics would be
called again and die while accessing the invalid debug instructions.
Differential Revision: http://reviews.llvm.org/D11423
llvm-svn: 243057
Adds pushes to the folding tables.
This also required a fix to the TD definition, since the memory forms of
the push instructions did not have the right mayLoad/mayStore flags.
Differential Revision: http://reviews.llvm.org/D11340
llvm-svn: 243010
The DAG Node "SCALAR_TO_VECTOR" may be created if the type of the scalar element is legal.
Added a check for the scalar type before creating this node.
Added a test that fails with assertion on the current version.
Differential Revision: http://reviews.llvm.org/D11413
llvm-svn: 242994
This commit broke the build. Numerous build bots broken, and it was
blocking my progress so reverting.
It should be trivial to reproduce -- enable the BPF backend and it
should fail when running llvm-tblgen.
llvm-svn: 242992
Summary:
This change generalizes the implicit null checks pass to work with
instructions that don't have any explicit register defs. This lets us
use X86's `cmp` against memory as faulting load instructions.
Reviewers: reames, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11286
llvm-svn: 242703
SKX supports conversion for all FP types. Integer types include doublewords and quardwords.
I added "Legal" status for these nodes and a bunch of tests.
I added "NoVLX" for AVX DAG selection to force VLX instructions selection when VLX is supported.
Differential Revision: http://reviews.llvm.org/D11255
llvm-svn: 242637
This adds new intrinsics "*absdiff" for absolute difference ops to facilitate efficient code generation for "sum of absolute differences" operation.
The patch also contains the introduction of corresponding SDNodes and basic legalization support.Sanity of the generated code is tested on X86.
This is 1st of the three patches.
Patch by Shahid Asghar-ahmad!
llvm-svn: 242409
This allows more call sequences to use pushes instead of movs when optimizing for size.
In particular, calling conventions that pass some parameters in registers (e.g. thiscall) are now supported.
This should no longer cause miscompiles, now that a bug in emitPrologue was fixed in r242395.
llvm-svn: 242398
- Teaches the ValueTracker in the PeepholeOptimizer to look through PHI
instructions.
- Add findNextSourceAndRewritePHI method to lookup into multiple sources
returnted by the ValueTracker and rewrite PHIs with new sources.
With these changes we can find more register sources and rewrite more
copies to allow coaslescing of bitcast instructions. Hence, we eliminate
unnecessary VR64 <-> GR64 copies in x86, but it could be extended to
other archs by marking "isBitcast" on target specific instructions. The
x86 example follows:
A:
psllq %mm1, %mm0
movd %mm0, %r9
jmp C
B:
por %mm1, %mm0
movd %mm0, %r9
jmp C
C:
movd %r9, %mm0
pshufw $238, %mm0, %mm0
Becomes:
A:
psllq %mm1, %mm0
jmp C
B:
por %mm1, %mm0
jmp C
C:
pshufw $238, %mm0, %mm0
Differential Revision: http://reviews.llvm.org/D11197
rdar://problem/20404526
llvm-svn: 242295
Current implementation handles unordered comparison poorly in soft-float mode.
Consider (a ULE b) which is a <= b. It is lowered to (ledf2(a, b) <= 0 || unorddf2(a, b) != 0) (in general). We can do better job by lowering it to (__gtdf2(a, b) <= 0).
Such replacement is true for other CMP's (ult, ugt, uge). In general, we just call same function as for ordered case but negate comparison against zero.
Differential Revision: http://reviews.llvm.org/D10804
llvm-svn: 242280
Summary:
Before this change, personality directives were not emitted
if there was no invoke left in the function (of course until
recently this also meant that we couldn't know what
the personality actually was). This patch forces personality directives
to still be emitted, unless it is known to be a noop in the absence of
invokes, or the user explicitly specified `nounwind` (and not
`uwtable`) on the function.
Reviewers: majnemer, rnk
Subscribers: rnk, llvm-commits
Differential Revision: http://reviews.llvm.org/D10884
llvm-svn: 242185
- Factor out code to query and modify the sign bit of a floatingpoint
value as an integer. This also works if none of the targets integer
types is big enough to hold all bits of the floatingpoint value.
- Legalize FABS(x) as FCOPYSIGN(x, 0.0) if FCOPYSIGN is available,
otherwise perform bit manipulation on the sign bit. The previous code
used "x >u 0 ? x : -x" which is incorrect for x being -0.0! It also
takes 34 instructions on ARM Cortex-M4. With this patch we only
require 5:
vldr d0, LCPI0_0
vmov r2, r3, d0
lsrs r2, r3, #31
bfi r1, r2, #31, #1
bx lr
(This could be further improved if the compiler would recognize that
r2, r3 is zero).
- Only lower FCOPYSIGN(x, y) = sign(x) ? -FABS(x) : FABS(x) if FABS is
available otherwise perform bit manipulation on the sign bit.
- Perform the sign(x) test by masking out the sign bit and comparing
with 0 rather than shifting the sign bit to the highest position and
testing for "<s 0". For x86 copysignl (on 80bit values) this gets us:
testl $32768, %eax
rather than:
shlq $48, %rax
sets %al
testb %al, %al
llvm-svn: 242107
The outlined funclets call intrinsics which reference labels from the
LSDA. This situation can easily arise in small functions with a single
cleanup at -O0, where Clang marks a definition as nounwind, and then
WinEHPrepare "discovers" that the landingpad is dead by accident and
deletes it.
We now need to ask the LLVM IR Function for it's personality directly,
rather than going through MachineModuleInfo.
Fixes PR23892.
llvm-svn: 242063
It had accidently accepted a symbol+offset value (and emitted
incorrect code for it, keeping only the offset part) instead of
properly reporting the constraint as invalid.
Differential Revision: http://reviews.llvm.org/D11039
llvm-svn: 242040
In this patch I have only encoding. Intrinsics and DAG lowering will be in the next patch.
I temporary removed the old intrinsics test (just to split this patch).
Half types are not covered here.
Differential Revision: http://reviews.llvm.org/D11134
llvm-svn: 242023
While the v4i32 shl operation is already vectorized using a cvttps2dq/pmulld pattern, the lshr/ashr opeations are still scalarized.
This patch adds vectorization support for non-uniform v4i32 shift operations - it splats constant shift amounts to allow them to use the immediate sse shift instructions, or extracts/zero-extends non-constant shift amounts. The individual results are then blended together.
Differential Revision: http://reviews.llvm.org/D11063
llvm-svn: 241989
If our two inputs have known top-zero bit counts M and N, we trivially
know that the output cannot have any bits set in the top (min(M, N)-1)
bits, since nothing could carry past that point.
llvm-svn: 241927
Apparently this is important, otherwise _except_handler3 assumes that
the registration node is corrupted and ignores it.
Also fix a bug in WinEHPrepare where we would insert code after a
terminator instruction.
llvm-svn: 241877
The runtime does not restore CSRs when transferring control back to the
function handling the exception. According to the experts on IRC, LLVM's
register allocator has no way to model register clobbers that only
happen on one edge of the CFG. For now, don't worry about trying to use
the meager three CSRs available on 32-bit X86 and just say that such
invokes preserve nothing.
llvm-svn: 241865
Summary:
Before this change ImplicitNullChecks would only pick loads of the form:
```
test Reg, Reg
jz elsewhere
fallthrough:
movl 32(Reg), Reg2
```
but not (say)
```
test Reg, Reg
jz elsewhere
fallthrough:
inc Reg3
movl 32(Reg), Reg2
```
This change teaches ImplicitNullChecks to look through "unrelated"
instructions like `inc Reg3` when searching for a load instruction
to convert to a trapping load.
Reviewers: atrick, JosephTremoulet, reames
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11044
llvm-svn: 241850
This patch allows the read_register and write_register intrinsics to
read/write the RBP/EBP registers on X86 iff the targeted register is
the frame pointer for the containing function.
Differential Revision: http://reviews.llvm.org/D10977
llvm-svn: 241827
This patch fixes bugs that were exposed by the addition of fast-math-flags in the DAG:
r237046 ( http://reviews.llvm.org/rL237046 ):
1. When replacing a division node, it's not enough to RAUW.
We should call CombineTo() to delete dead nodes and combine again.
2. Because we are changing the DAG, we can't return an empty SDValue
after the transform. As the code comments say:
Visitation implementation - Implement dag node combining for different node types.
The semantics are as follows: Return Value:
SDValue.getNode() == 0 - No change was made
SDValue.getNode() == N - N was replaced, is dead and has been handled.
otherwise - N should be replaced by the returned Operand.
The new test case shows no difference with or without this patch, but it will crash if
we re-apply r237046 or enable FMF via the current -enable-fmf-dag cl::opt.
Differential Revision: http://reviews.llvm.org/D9893
llvm-svn: 241826
Summary: If shift amount is a constant value > 64 bit it is handled incorrectly during type legalization and X86 lowering. This patch the type of shift amount argument in function DAGTypeLegalizer::ExpandShiftByConstant from unsigned to APInt.
Reviewers: nadav, majnemer, sanjoy, RKSimon
Subscribers: RKSimon, llvm-commits
Differential Revision: http://reviews.llvm.org/D10767
llvm-svn: 241806
Summary: If shift amount is a constant value > 64 bit it is handled incorrectly during type legalization and X86 lowering. This patch the type of shift amount argument in function DAGTypeLegalizer::ExpandShiftByConstant from unsigned to APInt.
Reviewers: nadav, majnemer, sanjoy, RKSimon
Subscribers: RKSimon, llvm-commits
Differential Revision: http://reviews.llvm.org/D10767
llvm-svn: 241790
The justification of this change is here: http://lists.cs.uiuc.edu/pipermail/llvmdev/2015-March/082989.html
According to the current GEP syntax, vector GEP requires that each index must be a vector with the same number of elements.
%A = getelementptr i8, <4 x i8*> %ptrs, <4 x i64> %offsets
In this implementation I let each index be or vector or scalar. All vector indices must have the same number of elements. The scalar value will mean the splat vector value.
(1) %A = getelementptr i8, i8* %ptr, <4 x i64> %offsets
or
(2) %A = getelementptr i8, <4 x i8*> %ptrs, i64 %offset
In all cases the %A type is <4 x i8*>
In the case (2) we add the same offset to all pointers.
The case (1) covers C[B[i]] case, when we have the same base C and different offsets B[i].
The documentation is updated.
http://reviews.llvm.org/D10496
llvm-svn: 241788
All the usual X86 target-specific conventions are collapsed to the
normal Win64 convention, but the custom conventions like GHC and webkit
should not be.
Previously we would assume that the caller allocated 32 bytes of shadow
space for us, which is not how webkit_jscc or other custom conventions
are supposed to work.
Based on a patch by peavo@outlook.com.
Fixes PR24051.
llvm-svn: 241725
The incoming EBP value points to the end of a local stack allocation, so
we can use that to restore ESI, the base pointer. Once we do that, we
can use local stack allocations. If we know we need stack realignment,
spill the original frame pointer in the prologue and reload it after
restoring ESI.
llvm-svn: 241648
Summary:
Initially, these intrinsics seemed like part of a family of "frame"
related intrinsics, but now I think that's more confusing than helpful.
Initially, the LangRef specified that this would create a new kind of
allocation that would be allocated at a fixed offset from the frame
pointer (EBP/RBP). We ended up dropping that design, and leaving the
stack frame layout alone.
These intrinsics are really about sharing local stack allocations, not
frame pointers. I intend to go further and add an `llvm.localaddress()`
intrinsic that returns whatever register (EBP, ESI, ESP, RBX) is being
used to address locals, which should not be confused with the frame
pointer.
Naming suggestions at this point are welcome, I'm happy to re-run sed.
Reviewers: majnemer, nicholas
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11011
llvm-svn: 241633
The vperm2f128/vperm2i128 shuffle mask decoding was not attempting to deal with shuffles that give zero lanes. This patch fixes this so that the assembly printer can provide shuffle comments.
As this decoder is also used in X86ISelLowering for shuffle combining, I've added an early-out to match existing behaviour. The hope is that we can add zero support in the future, this would allow other ops' decodes (e.g. insertps) to be combined as well.
Differential Revision: http://reviews.llvm.org/D10593
llvm-svn: 241516
Extend the reassociation optimization of http://reviews.llvm.org/rL240361 (D10460)
to SSE scalar FP SP adds in addition to AVX scalar FP SP adds.
With the 'switch' in place, we can trivially add other opcodes and test cases in
future patches.
Differential Revision: http://reviews.llvm.org/D10975
llvm-svn: 241515
This patch adds vectorization support for uniform constant i64 arithmetic shift right operators.
Differential Revision: http://reviews.llvm.org/D9645
llvm-svn: 241514
This patch adds support for v8i16 and v16i8 shuffle lowering using the immediate versions of the SSE4A EXTRQ and INSERTQ instructions. Although rather limited (they can only act on the lower 64-bits of the source vectors, leave the upper 64-bits of the result vector undefined and don't have VEX encoded variants), the instructions are still useful for the zero extension of any lane (EXTRQ) or inserting a lane into another vector (INSERTQ). Testing demonstrated that it wasn't typically worth it to use these instructions for v2i64 or v4i32 vector shuffles although they are capable of it.
As well as adding specific pattern matching for the shuffles, the patch uses EXTRQ for zero extension cases where SSE41 isn't available and its more efficient than the SSE2 'unpack' default approach. It also adds shuffle decode support for the EXTRQ / INSERTQ cases when the instructions are handling full byte-sized extractions / insertions.
From this foundation, future patches will be able to make use of the instructions for situations that use their ability to extract/insert at the bit level.
Differential Revision: http://reviews.llvm.org/D10146
llvm-svn: 241508
Followup to D10433 and D10589 that fixes i8/i16 uint2fp vector conversions by zero extending to i32 and using the sint2fp path (unless the target does actually support uint2fp).
llvm-svn: 241394
Add support for v2i8/v2i16 to v2f64 by using a sign extension to v2i32 before conversion to v2f64.
Differential Revision: http://reviews.llvm.org/D10589
llvm-svn: 241325
This patch adds support for sign extension for sub 128-bit vectors, such as to v2i32. It concatenates with UNDEF subvectors up to 128-bits, performs the sign extension (i.e. as v4i32) and then extracts the target subvector.
Patch 1/2 of D10589 - the second patch covers the conversion of v2i8/v2i16 to v2f64.
llvm-svn: 241323
The code responsible for shl folding in the DAGCombiner was assuming incorrectly that all constants are less than 64 bits. This patch simply changes the way values are compared.
It has been reverted previously because of some problems with comparing APInt with raw uint64_t. That has been fixed/changed with r241204.
llvm-svn: 241254
TwoAddressInstructionPass stops after a successful commuting but 3 Addr
conversion might be good for some cases.
Consider:
int foo(int a, int b) {
return a + b;
}
Before this commit, we emit:
addl %esi, %edi
movl %edi, %eax
ret
After this commit, we try 3 Addr conversion:
leal (%rsi,%rdi), %eax
ret
Patch by Volkan Keles <vkeles@apple.com>!
Differential Revision: http://reviews.llvm.org/D10851
llvm-svn: 241206
This patch is not intended to change existing codegen behavior for any target.
It just exposes the JumpIsExpensive setting on the command-line to allow for
easier testing and emergency overrides.
Also, change the existing regression test to use FileCheck, explicitly specify
the jump-is-expensive option, and use more precise checks.
Differential Revision: http://reviews.llvm.org/D10846
llvm-svn: 241179
The EH code might have been deleted as unreachable and the personality
pruned while the filter is still present. Currently I'm hitting this at
-O0 due to the clang bug PR24009.
llvm-svn: 241170
The incoming EBP value established by the runtime is actually a pointer
to the end of the EH registration object, and not the true parent
function frame pointer. Clang doesn't need llvm.x86.seh.exceptioninfo
anymore because we know that the exception info pointer is at a fixed
offset from this incoming EBP.
The llvm.x86.seh.recoverfp intrinsic takes an EBP value provided by the
EH runtime and returns a pointer that is usable with llvm.framerecover.
The llvm.x86.seh.restoreframe intrinsic is inserted by the 32-bit
specific preparation pass in blocks targetted by the EH runtime. It
re-establishes any physical registers used by the parent function to
address the stack, such as the frame, base, and stack pointers.
Neither of these intrinsics correctly handle stack realignment prologues
yet, but it's possible to add that later.
Reviewers: majnemer
Differential Revision: http://reviews.llvm.org/D10848
llvm-svn: 241125
Summary:
This change introduces a !make.implicit metadata that allows the
frontend to pre-select the set of explicit null checks that will be
considered for transformation into implicit null checks.
The reason for not using profiling data instead of !make.implicit is
explained in the change to `FaultMaps.rst`.
Reviewers: atrick, reames, pgavlin, JosephTremoulet
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D10824
llvm-svn: 241116
It is mandatory to specify a comdat in order to receive comdat semantics
for a symbol. We were previously getting this wrong in -function-sections
mode; linker-weak symbols were being emitted in a selectany comdat. This
change causes such symbols to use a noduplicates comdat instead, fixing
the inconsistency.
Also correct an inaccuracy in the docs.
Differential Revision: http://reviews.llvm.org/D10828
llvm-svn: 241103
Sanjay Patel