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Differential D45381

[SimplifyLibcalls] Remove the hasOneUse() limitation on the malloc
AbandonedPublic

Authored by xbolva00 on Apr 6 2018, 11:17 AM.

Details

Reviewers
spatel
lebedev.ri
Summary

Discussion and part of https://reviews.llvm.org/D45344

The reason that's there is discussed in D16337 - the transform must be made safe from intermediate stores.

Diff Detail

Repository
rL LLVM

Event Timeline

xbolva00 created this revision.Apr 6 2018, 11:17 AM
Herald added a subscriber: llvm-commits. · View Herald TranscriptApr 6 2018, 11:17 AM
xbolva00 updated this revision to Diff 141387.Apr 6 2018, 11:19 AM
spatel mentioned this in D45344: [SimplifyLibcalls] Fold malloc + memset to calloc even for llvm.memset.Apr 6 2018, 2:49 PM
xbolva00 retitled this revision from [InstCombine] Remove the hasOneUse() limitation on the malloc to [SimplifyLibcalls] Remove the hasOneUse() limitation on the malloc.Apr 6 2018, 3:13 PM
xbolva00 added a reviewer: lebedev.ri.Apr 7 2018, 4:19 AM
xbolva00 edited the summary of this revision. (Show Details)
xbolva00 abandoned this revision.Apr 7 2018, 4:36 AM

Revision Contents

PathSize
lib/
Transforms/
Utils/
6 lines

Diff 141385

lib/Transforms/Utils/SimplifyLibCalls.cpp

Context not available.
if (!FillValue || FillValue->getZExtValue() != 0) if (!FillValue || FillValue->getZExtValue() != 0)
return nullptr; return nullptr;
// TODO: We should handle the case where the malloc has more than one use.
// This is necessary to optimize common patterns such as when the result of
// the malloc is checked against null or when a memset intrinsic is used in
// place of a memset library call.
auto *Malloc = dyn_cast<CallInst>(Memset->getArgOperand(0)); auto *Malloc = dyn_cast<CallInst>(Memset->getArgOperand(0));
if (!Malloc || !Malloc->hasOneUse()) if (!Malloc)
return nullptr; return nullptr;
// Is the inner call really malloc()? // Is the inner call really malloc()?
Context not available.