Index: llvm/include/llvm/CodeGen/FastISel.h =================================================================== --- llvm/include/llvm/CodeGen/FastISel.h +++ llvm/include/llvm/CodeGen/FastISel.h @@ -490,7 +490,10 @@ /// - \c Add has a constant operand. bool canFoldAddIntoGEP(const User *GEP, const Value *Add); - /// Test whether the given value has exactly one use. + /// Test whether the register associated with this value has exactly one use, + /// in which case that single use is killing. Note that multiple IR values + /// may map onto the same register, in which case this is not the same as + /// checking that an IR value has one use. bool hasTrivialKill(const Value *V); /// Create a machine mem operand from the given instruction. Index: llvm/lib/CodeGen/SelectionDAG/FastISel.cpp =================================================================== --- llvm/lib/CodeGen/SelectionDAG/FastISel.cpp +++ llvm/lib/CodeGen/SelectionDAG/FastISel.cpp @@ -266,7 +266,8 @@ return I->hasOneUse() && !(I->getOpcode() == Instruction::BitCast || I->getOpcode() == Instruction::PtrToInt || - I->getOpcode() == Instruction::IntToPtr) && + I->getOpcode() == Instruction::IntToPtr || + I->getOpcode() == Instruction::ExtractValue) && cast(*I->user_begin())->getParent() == I->getParent(); } Index: llvm/test/CodeGen/X86/pr49467.ll =================================================================== --- /dev/null +++ llvm/test/CodeGen/X86/pr49467.ll @@ -0,0 +1,27 @@ +; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py +; RUN: llc -O0 -fast-isel -verify-machineinstrs -mtriple=x86_64 < %s | FileCheck %s + +declare { i8*, i64 } @get() + +declare void @use(i8*, i64) + +define void @test(i64* %p) nounwind { +; CHECK-LABEL: test: +; CHECK: # %bb.0: +; CHECK-NEXT: pushq %rax +; CHECK-NEXT: movq %rdi, (%rsp) # 8-byte Spill +; CHECK-NEXT: callq get@PLT +; CHECK-NEXT: movq (%rsp), %rdi # 8-byte Reload +; CHECK-NEXT: movq %rdx, %rsi +; CHECK-NEXT: movq %rsi, (%rdi) +; CHECK-NEXT: # implicit-def: $rdi +; CHECK-NEXT: callq use@PLT +; CHECK-NEXT: popq %rax +; CHECK-NEXT: retq + %struct = call { i8*, i64 } @get() + %struct.1 = extractvalue { i8*, i64 } %struct, 1 + store i64 %struct.1, i64* %p, align 8 + %struct.2 = extractvalue { i8*, i64 } %struct, 1 + call void @use(i8* undef, i64 %struct.2) + ret void +}