Index: llvm/trunk/lib/CodeGen/LivePhysRegs.cpp =================================================================== --- llvm/trunk/lib/CodeGen/LivePhysRegs.cpp +++ llvm/trunk/lib/CodeGen/LivePhysRegs.cpp @@ -225,10 +225,10 @@ void LivePhysRegs::addLiveOuts(const MachineBasicBlock &MBB) { const MachineFunction &MF = *MBB.getParent(); - if (!MBB.succ_empty()) { + if (!MBB.isReturnBlock()) { addPristines(MF); addLiveOutsNoPristines(MBB); - } else if (MBB.isReturnBlock()) { + } else { // For the return block: Add all callee saved registers. const MachineFrameInfo &MFI = MF.getFrameInfo(); if (MFI.isCalleeSavedInfoValid()) Index: llvm/trunk/test/CodeGen/Thumb/stm-scavenging.ll =================================================================== --- llvm/trunk/test/CodeGen/Thumb/stm-scavenging.ll +++ llvm/trunk/test/CodeGen/Thumb/stm-scavenging.ll @@ -0,0 +1,47 @@ +; RUN: llc < %s | FileCheck %s +target triple = "thumbv6---gnueabi" + +; Use STM to save the three registers +; CHECK-LABEL: use_stm: +; CHECK: .save {r7, lr} +; CHECK: .setfp r7, sp +; CHECK: stm r3!, {r0, r1, r2} +; CHECK: bl throws_1 +define void @use_stm(i32 %a, i32 %b, i32 %c, i32* %d) local_unnamed_addr noreturn "no-frame-pointer-elim"="true" { +entry: + %arrayidx = getelementptr inbounds i32, i32* %d, i32 2 + store i32 %a, i32* %arrayidx, align 4 + %arrayidx1 = getelementptr inbounds i32, i32* %d, i32 3 + store i32 %b, i32* %arrayidx1, align 4 + %arrayidx2 = getelementptr inbounds i32, i32* %d, i32 4 + store i32 %c, i32* %arrayidx2, align 4 + tail call void @throws_1(i32 %a, i32 %b, i32 %c) noreturn + unreachable +} + +; Don't use STM: there is no available register to store +; the address. We could transform this with some extra math, but +; that currently isn't implemented. +; CHECK-LABEL: no_stm: +; CHECK: .save {r7, lr} +; CHECK: .setfp r7, sp +; CHECK: str r0, +; CHECK: str r1, +; CHECK: str r2, +; CHECK: bl throws_2 +define void @no_stm(i32 %a, i32 %b, i32 %c, i32* %d) local_unnamed_addr noreturn "no-frame-pointer-elim"="true" { +entry: + %arrayidx = getelementptr inbounds i32, i32* %d, i32 2 + store i32 %a, i32* %arrayidx, align 4 + %arrayidx1 = getelementptr inbounds i32, i32* %d, i32 3 + store i32 %b, i32* %arrayidx1, align 4 + %arrayidx2 = getelementptr inbounds i32, i32* %d, i32 4 + store i32 %c, i32* %arrayidx2, align 4 + tail call void @throws_2(i32 %a, i32 %b, i32 %c, i32* %d) noreturn + unreachable +} + + +declare void @throws_1(i32, i32, i32) noreturn +declare void @throws_2(i32, i32, i32, i32*) noreturn +