The motivating example is:
extern int patatino;
int goo() {
int x = 0;
for (int i = 0; i < 1000000; ++i) {
x *= patatino;
}
return x;
}
Currently SCCP will not realize that this function returns always zero,
therefore will try to unroll and vectorize the loop at -O3 producing an
awful lot of (useless) code. With this change, it will just produce:
0000000000000000 <g>:
xor %eax,%eax
retq
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289175 91177308-0d34-0410-b5e6-96231b3b80d8
Supporting them properly is a reasonably complex chunk of work, so to allow bot
testing before then we should at least be able to fall back to DAG ISel.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289150 91177308-0d34-0410-b5e6-96231b3b80d8
Currently SCCP folds the value to -1, while ConstantProp folds to
0. This changes SCCP to do what ConstantFolding does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289147 91177308-0d34-0410-b5e6-96231b3b80d8
We were falsely claiming that we had an LSDA for the relevant EH
personality before this change, which could lead to the EH machinery
interpreting random adjacent data as an LSDA.
Fixes PR31317
This change is safe because cleanups can't contain exception handlers
today. We do these things to maintain that invariant:
- C++ destructors are naturally out-of-line
- __finally blocks are outlined in clang
- LLVM's inliner will not inline EH constructs into cleanups
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289101 91177308-0d34-0410-b5e6-96231b3b80d8
Not having this legal led to combine failures, resulting
in dumb things like bitcasts of constants not being folded
away.
The only reason I'm leaving the v_mov_b32 hack that f32
already uses is to avoid madak formation test regressions.
PeepholeOptimizer has an ordering issue where the immediate
fold attempt is into the sgpr->vgpr copy instead of the actual
use. Running it twice avoids that problem.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289096 91177308-0d34-0410-b5e6-96231b3b80d8
The correct commutable opcode was set to itself, so this
was simply swapping the operands to commute instead of also
changing the opcode to v_subrev_u16.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289093 91177308-0d34-0410-b5e6-96231b3b80d8
Multiple metadata values for records such as opencl.ocl.version, llvm.ident
and similar are created after linking several modules. For some of them, notably
opencl.ocl.version, this creates semantic problem because we cannot tell which
version of OpenCL the composite module conforms.
Moreover, such repetitions of identical values often create a huge list of
unneeded metadata, which grows bitcode size both in memory and stored on disk.
It can go up to several Mb when linked against our OpenCL library. Lastly, such
long lists obscure reading of dumped IR.
The pass unifies metadata after linking.
Differential Revision: https://reviews.llvm.org/D25381
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Summary:
Attaching !absolute_symbol to a global variable does two things:
1) Marks it as an absolute symbol reference.
2) Specifies the value range of that symbol's address.
Teach the X86 backend to allow absolute symbols to appear in place of
immediates by extending the relocImm and mov64imm32 matchers. Start using
relocImm in more places where it is legal.
As previously proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105800.html
Differential Revision: https://reviews.llvm.org/D25878
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Summary:
LC can currently select scalar load for uniform memory access
basing on readonly memory address space only. This restriction
originated from the fact that in HW prior to VI vector and scalar caches
are not coherent. With MemoryDependenceAnalysis we can check that the
memory location corresponding to the memory operand of the LOAD is not
clobbered along the all paths from the function entry.
Reviewers: rampitec, tstellarAMD, arsenm
Subscribers: wdng, arsenm, nhaehnle
Differential Revision: https://reviews.llvm.org/D26917
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289076 91177308-0d34-0410-b5e6-96231b3b80d8
ConstantFolding tried to cast one of the scalar indices to a vector
type. Instead, use the vector type only for the first index (which
is the only one allowed to be a vector) and use its scalar type
otherwise.
Fixes PR31250.
Reviewers: majnemer
Differential Revision: https://reviews.llvm.org/D27389
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289073 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Without the fix to isFrameOffsetLegal to consider the instruction's
immediate offset, the new test case hits the corresponding assertion in
resolveFrameIndex, because the LocalStackSlotAllocation pass re-uses a
different base register.
With only the fix to isFrameOffsetLegal, code quality reduces in a bunch of
places because frame base registers are added where they're not needed.
This is addressed by properly implementing needsFrameBaseReg, which also
helps to avoid unnecessary zero frame indices in a bunch of other places.
Fixes piglit glsl-1.50/execution/variable-indexing/gs-output-array-vec4-index-wr.shader_test
Reviewers: arsenm, tstellarAMD
Subscribers: qcolombet, kzhuravl, wdng, yaxunl, tony-tye, llvm-commits
Differential Revision: https://reviews.llvm.org/D27344
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289048 91177308-0d34-0410-b5e6-96231b3b80d8
When trying to vectorize trees that start at insertelement instructions
function tryToVectorizeList() uses vectorization factor calculated as
MinVecRegSize/ScalarTypeSize. But sometimes it does not work as tree
cost for this fixed vectorization factor is too high.
Patch tries to improve the situation. It tries different vectorization
factors from max(PowerOf2Floor(NumberOfVectorizedValues),
MinVecRegSize/ScalarTypeSize) to MinVecRegSize/ScalarTypeSize and tries
to choose the best one.
Differential Revision: https://reviews.llvm.org/D27215
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The relocations for `DIEEntry::EmitValue` were wrong for Win64
(emitting FK_Data_4 instead of FK_SecRel_4). This corrects that
oversight so that the DWARF data is correct in Win64 COFF files.
Fixes PR15393.
Patch by Jameson Nash <jameson@juliacomputing.com> based on a patch
by David Majnemer.
Differential Revision: https://reviews.llvm.org/D21731
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Replace @progbits in the section directive with %progbits, because "@" starts a comment on arm/thumb.
Use b.w branch instruction.
Use .thumb_function and .thumb_set for proper arm/thumb interwork. This way jumptable entry addresses on thumb have bit 0 set (correctly). This does not affect CFI check math, because the address of the jumptable start also has that bit set.
This does not work on thumbv5, because it does not support b.w, and the linker would not insert a veneer (trampoline?) to extend the range of b.n. We may need to do full-range plt-style jumptables on thumbv54, which are 12 bytes per entry. Another option is "push lr; bl; pop pc" (4 bytes) but that needs unwinding instructions, etc.
Differential Revision: https://reviews.llvm.org/D27499
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@289008 91177308-0d34-0410-b5e6-96231b3b80d8
The fix committed in r288851 doesn't cover all the cases.
In particular, if we have an instruction with side effects
which has a no non-dbg use not depending on the bits, we still
perform RAUW destroying the dbg.value's first argument.
Prevent metadata from being replaced here to avoid the issue.
Differential Revision: https://reviews.llvm.org/D27534
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288987 91177308-0d34-0410-b5e6-96231b3b80d8
ConstantExpr instances were emitting code into the current block rather than
the entry block. This meant they didn't necessarily dominate all uses, which is
clearly wrong.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288985 91177308-0d34-0410-b5e6-96231b3b80d8
This change makes the yaml tags for the members of the DWARF data match the names of the DWARF sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288981 91177308-0d34-0410-b5e6-96231b3b80d8
MachineIRBuilder had weird before/after and beginning/end flags for the insert
point. Unfortunately the non-default means that instructions will be inserted
in reverse order which is almost never what anyone wants.
Really, I think we just want (like IRBuilder has) the ability to insert at any
C++ iterator-style point (i.e. before any instruction or before MBB.end()). So
this fixes MIRBuilders to behave like IRBuilders in this respect.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288980 91177308-0d34-0410-b5e6-96231b3b80d8
The tests that already work are folded in InstSimplify, so those
tests should be redundant and we can remove them if they don't
seem worthwhile for completeness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@288957 91177308-0d34-0410-b5e6-96231b3b80d8
