Index: lib/CodeGen/CGCall.cpp =================================================================== --- lib/CodeGen/CGCall.cpp +++ lib/CodeGen/CGCall.cpp @@ -2896,15 +2896,6 @@ RV = SI->getValueOperand(); SI->eraseFromParent(); - // If that was the only use of the return value, nuke it as well now. - auto returnValueInst = ReturnValue.getPointer(); - if (returnValueInst->use_empty()) { - if (auto alloca = dyn_cast(returnValueInst)) { - alloca->eraseFromParent(); - ReturnValue = Address::invalid(); - } - } - // Otherwise, we have to do a simple load. } else { RV = Builder.CreateLoad(ReturnValue); Index: lib/CodeGen/CodeGenFunction.cpp =================================================================== --- lib/CodeGen/CodeGenFunction.cpp +++ lib/CodeGen/CodeGenFunction.cpp @@ -255,6 +255,7 @@ if (CurBB->empty() || ReturnBlock.getBlock()->use_empty()) { ReturnBlock.getBlock()->replaceAllUsesWith(CurBB); delete ReturnBlock.getBlock(); + ReturnBlock = JumpDest(); } else EmitBlock(ReturnBlock.getBlock()); return llvm::DebugLoc(); @@ -274,6 +275,7 @@ Builder.SetInsertPoint(BI->getParent()); BI->eraseFromParent(); delete ReturnBlock.getBlock(); + ReturnBlock = JumpDest(); return Loc; } } @@ -448,6 +450,19 @@ // 5. Width of vector aguments and return types for functions called by this // function. CurFn->addFnAttr("min-legal-vector-width", llvm::utostr(LargestVectorWidth)); + + // If we generated an unreachable return block, delete it now. + if (ReturnBlock.isValid() && ReturnBlock.getBlock()->use_empty()) { + Builder.ClearInsertionPoint(); + ReturnBlock.getBlock()->eraseFromParent(); + } + if (ReturnValue.isValid()) { + auto *RetAlloca = dyn_cast(ReturnValue.getPointer()); + if (RetAlloca && RetAlloca->use_empty()) { + RetAlloca->eraseFromParent(); + ReturnValue = Address::invalid(); + } + } } /// ShouldInstrumentFunction - Return true if the current function should be Index: test/CodeGen/unreachable-ret.c =================================================================== --- /dev/null +++ test/CodeGen/unreachable-ret.c @@ -0,0 +1,23 @@ +// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s + +extern void abort() __attribute__((noreturn)); + +void f1() { + abort(); +} +// CHECK-LABEL: define void @f1() +// CHECK-NEXT: entry: +// CHECK-NEXT: call void @abort() +// CHECK-NEXT: unreachable +// CHECK-NEXT: } + +void *f2() { + abort(); + return 0; +} +// CHECK-LABEL: define i8* @f2() +// CHECK-NEXT: entry: +// CHECK-NEXT: call void @abort() +// CHECK-NEXT: unreachable +// CHECK-NEXT: } + Index: test/OpenMP/parallel_reduction_codegen.cpp =================================================================== --- test/OpenMP/parallel_reduction_codegen.cpp +++ test/OpenMP/parallel_reduction_codegen.cpp @@ -622,7 +622,7 @@ // CHECK-NOT: call i32 @__kmpc_reduce -// CHECK: ret void +// CHECK: } // CHECK: define {{.*}} i{{[0-9]+}} [[TMAIN_INT]]() // CHECK: [[TEST:%.+]] = alloca [[S_INT_TY]],