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| author |   Roman Lebedev <lebedev.ri@gmail.com> | 2021-04-10 00:31:56 +0300 |
|---|---|---|
| committer | Roman Lebedev <lebedev.ri@gmail.com> | 2021-04-10 00:56:28 +0300 |
| commit | 077bff39d46364035a5dcfa32fc69910ad0975d0 (patch) | |
| tree | bb125d668e537244529013b0265ab57bbffa494c | |
| parent | [NFC][SROA] Add C++'s `std::clamp()` testcase from PR47271/PR49909 (diff) | |
| download | llvm-project-077bff39d46364035a5dcfa32fc69910ad0975d0.tar.gz llvm-project-077bff39d46364035a5dcfa32fc69910ad0975d0.tar.bz2 llvm-project-077bff39d46364035a5dcfa32fc69910ad0975d0.zip | |
[Analysis] isDereferenceableAndAlignedPointer(): recurse into select's hands
By doing this within the method itself,
we support traversing multiple levels of selects (TODO: PHI's),
fixing the SROA `std::clamp()` testcase.
Fixes https://bugs.llvm.org/show_bug.cgi?id=47271
Mostly fixes https://bugs.llvm.org/show_bug.cgi?id=49909
| -rw-r--r-- | llvm/lib/Analysis/Loads.cpp | 10 | ||||
| -rw-r--r-- | llvm/test/Transforms/SROA/std-clamp.ll | 14 |
2 files changed, 15 insertions, 9 deletions
diff --git a/llvm/lib/Analysis/Loads.cpp b/llvm/lib/Analysis/Loads.cpp index 8d01ea045097..2ae1fd5b5bde 100644 --- a/llvm/lib/Analysis/Loads.cpp +++ b/llvm/lib/Analysis/Loads.cpp @@ -59,6 +59,16 @@ static bool isDereferenceableAndAlignedPointer( // Note that it is not safe to speculate into a malloc'd region because // malloc may return null. + // Recurse into both hands of select. + if (const SelectInst *Sel = dyn_cast<SelectInst>(V)) { + return isDereferenceableAndAlignedPointer(Sel->getTrueValue(), Alignment, + Size, DL, CtxI, DT, TLI, Visited, + MaxDepth) && + isDereferenceableAndAlignedPointer(Sel->getFalseValue(), Alignment, + Size, DL, CtxI, DT, TLI, Visited, + MaxDepth); + } + // bitcast instructions are no-ops as far as dereferenceability is concerned. if (const BitCastOperator *BC = dyn_cast<BitCastOperator>(V)) { if (BC->getSrcTy()->isPointerTy()) diff --git a/llvm/test/Transforms/SROA/std-clamp.ll b/llvm/test/Transforms/SROA/std-clamp.ll index 561904252288..c0132a519722 100644 --- a/llvm/test/Transforms/SROA/std-clamp.ll +++ b/llvm/test/Transforms/SROA/std-clamp.ll @@ -6,18 +6,14 @@ target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16 define float @_Z8stdclampfff(float %x, float %lo, float %hi) { ; CHECK-LABEL: @_Z8stdclampfff( ; CHECK-NEXT: bb: -; CHECK-NEXT: [[I:%.*]] = alloca float, align 4 -; CHECK-NEXT: [[I3:%.*]] = alloca float, align 4 ; CHECK-NEXT: [[I4:%.*]] = alloca float, align 4 -; CHECK-NEXT: store float [[X:%.*]], float* [[I]], align 4 -; CHECK-NEXT: store float [[LO:%.*]], float* [[I3]], align 4 ; CHECK-NEXT: store float [[HI:%.*]], float* [[I4]], align 4 -; CHECK-NEXT: [[I5:%.*]] = fcmp fast olt float [[X]], [[LO]] +; CHECK-NEXT: [[I5:%.*]] = fcmp fast olt float [[X:%.*]], [[LO:%.*]] ; CHECK-NEXT: [[I6:%.*]] = fcmp fast olt float [[HI]], [[X]] -; CHECK-NEXT: [[I7:%.*]] = select i1 [[I6]], float* [[I4]], float* [[I]] -; CHECK-NEXT: [[I8:%.*]] = select i1 [[I5]], float* [[I3]], float* [[I7]] -; CHECK-NEXT: [[I9:%.*]] = load float, float* [[I8]], align 4 -; CHECK-NEXT: ret float [[I9]] +; CHECK-NEXT: [[I9_SROA_SPECULATE_LOAD_FALSE_SROA_SPECULATE_LOAD_TRUE:%.*]] = load float, float* [[I4]], align 4 +; CHECK-NEXT: [[I9_SROA_SPECULATE_LOAD_FALSE_SROA_SPECULATED:%.*]] = select i1 [[I6]], float [[I9_SROA_SPECULATE_LOAD_FALSE_SROA_SPECULATE_LOAD_TRUE]], float [[X]] +; CHECK-NEXT: [[I9_SROA_SPECULATED:%.*]] = select i1 [[I5]], float [[LO]], float [[I9_SROA_SPECULATE_LOAD_FALSE_SROA_SPECULATED]] +; CHECK-NEXT: ret float [[I9_SROA_SPECULATED]] ; bb: %i = alloca float, align 4 |