diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp index 3483032651a..310aab43d28 100644 --- a/lib/Transforms/Utils/Local.cpp +++ b/lib/Transforms/Utils/Local.cpp @@ -229,6 +229,11 @@ bool llvm::ConstantFoldTerminator(BasicBlock *BB, bool DeleteDeadConditions, SIDef->getValue().getZExtValue())); } + // Update make.implicit metadata to the newly-created conditional branch. + MDNode *MakeImplicitMD = SI->getMetadata(LLVMContext::MD_make_implicit); + if (MakeImplicitMD) + NewBr->setMetadata(LLVMContext::MD_make_implicit, MakeImplicitMD); + // Delete the old switch. SI->eraseFromParent(); return true; diff --git a/test/Transforms/SimplifyCFG/preserve-make-implicit-on-switch-to-br.ll b/test/Transforms/SimplifyCFG/preserve-make-implicit-on-switch-to-br.ll new file mode 100644 index 00000000000..0e95336bbc1 --- /dev/null +++ b/test/Transforms/SimplifyCFG/preserve-make-implicit-on-switch-to-br.ll @@ -0,0 +1,30 @@ +; RUN: opt %s -simplifycfg -S | FileCheck %s + +; ConstantFoldTerminator function can convert SwitchInst with one case (and default) to +; a conditional BranchInst. This test checks the converted BranchInst preserve the +; make.implicit metadata. + +declare i32 @consume(i32*) +declare void @trap() + +define i32 @copy-metadata(i32* %x) { + +entry: + %x.int = ptrtoint i32* %x to i64 + +; CHECK: br i1 %cond, label %is_null, label %default, !make.implicit !0 + switch i64 %x.int, label %default [ + i64 0, label %is_null + ], !make.implicit !0 + +default: + %0 = call i32 @consume(i32* %x) + ret i32 %0 + +is_null: + call void @trap() + unreachable +} + +!0 = !{} +