diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp --- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp +++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp @@ -2638,6 +2638,13 @@ Users.emplace_back(I); continue; } + + if (isReallocLikeFn(I, TLI, true)) { + Users.emplace_back(I); + Worklist.push_back(I); + continue; + } + return false; case Instruction::Store: { diff --git a/llvm/test/Transforms/InstCombine/alloc-realloc-free.ll b/llvm/test/Transforms/InstCombine/alloc-realloc-free.ll new file mode 100644 --- /dev/null +++ b/llvm/test/Transforms/InstCombine/alloc-realloc-free.ll @@ -0,0 +1,24 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --scrub-attributes +; RUN: opt -S -instcombine < %s | FileCheck %s + +define dso_local void @test() local_unnamed_addr #0 { +; CHECK-LABEL: @test( +; CHECK-NEXT: ret void +; + %1 = tail call noalias align 16 dereferenceable_or_null(4) i8* @malloc(i64 4) #4 + %2 = tail call align 16 dereferenceable_or_null(6) i8* @realloc(i8* %1, i64 6) #4 + tail call void @free(i8* %2) #4 + ret void +} + +declare dso_local noalias noundef i8* @malloc(i64 noundef) local_unnamed_addr #1 +declare dso_local noalias noundef i8* @realloc(i8* nocapture, i64 noundef) local_unnamed_addr #2 +declare dso_local void @free(i8* nocapture noundef) local_unnamed_addr #2 +declare void @llvm.dbg.value(metadata, metadata, metadata) #3 + +attributes #0 = { mustprogress nounwind uwtable willreturn } +attributes #1 = { inaccessiblememonly mustprogress nofree nounwind willreturn } +attributes #2 = { inaccessiblemem_or_argmemonly mustprogress nounwind willreturn } +attributes #3 = { nofree nosync nounwind readnone speculatable willreturn } +attributes #4 = { nounwind } +