diff options
| -rw-r--r-- | lib/Target/X86/X86FrameLowering.cpp | 29 | ||||
| -rw-r--r-- | test/CodeGen/X86/segmented-stacks.ll | 2 |
2 files changed, 25 insertions, 6 deletions
diff --git a/lib/Target/X86/X86FrameLowering.cpp b/lib/Target/X86/X86FrameLowering.cpp index 757cef2d7f..07e0d0ed26 100644 --- a/lib/Target/X86/X86FrameLowering.cpp +++ b/lib/Target/X86/X86FrameLowering.cpp @@ -1336,15 +1336,28 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const { if (Is64Bit) IsNested = HasNestArgument(&MF); + // The MOV R10, RAX needs to be in a different block, since the RET we emit in + // allocMBB needs to be last (terminating) instruction. + MachineBasicBlock *restoreR10MBB = NULL; + if (IsNested) + restoreR10MBB = MF.CreateMachineBasicBlock(); + for (MachineBasicBlock::livein_iterator i = prologueMBB.livein_begin(), e = prologueMBB.livein_end(); i != e; i++) { allocMBB->addLiveIn(*i); checkMBB->addLiveIn(*i); + + if (IsNested) + restoreR10MBB->addLiveIn(*i); } - if (IsNested) + if (IsNested) { allocMBB->addLiveIn(X86::R10); + restoreR10MBB->addLiveIn(X86::RAX); + } + if (IsNested) + MF.push_front(restoreR10MBB); MF.push_front(allocMBB); MF.push_front(checkMBB); @@ -1414,13 +1427,19 @@ X86FrameLowering::adjustForSegmentedStacks(MachineFunction &MF) const { if (!Is64Bit) BuildMI(allocMBB, DL, TII.get(X86::ADD32ri), X86::ESP).addReg(X86::ESP) .addImm(8); + BuildMI(allocMBB, DL, TII.get(X86::RET)); - if (Is64Bit && IsNested) - BuildMI(allocMBB, DL, TII.get(X86::MOV64rr), X86::R10).addReg(X86::RAX); + if (IsNested) + BuildMI(restoreR10MBB, DL, TII.get(X86::MOV64rr), X86::R10) + .addReg(X86::RAX); - BuildMI(allocMBB, DL, TII.get(X86::RET)); + if (IsNested) { + allocMBB->addSuccessor(restoreR10MBB); + restoreR10MBB->addSuccessor(&prologueMBB); + } else { + allocMBB->addSuccessor(&prologueMBB); + } - allocMBB->addSuccessor(&prologueMBB); checkMBB->addSuccessor(allocMBB); checkMBB->addSuccessor(&prologueMBB); diff --git a/test/CodeGen/X86/segmented-stacks.ll b/test/CodeGen/X86/segmented-stacks.ll index 37f082c730..ecdb00d5d1 100644 --- a/test/CodeGen/X86/segmented-stacks.ll +++ b/test/CodeGen/X86/segmented-stacks.ll @@ -81,7 +81,7 @@ define i32 @test_nested(i32 * nest %closure, i32 %other) { ; X64-NEXT: movabsq $0, %r10 ; X64-NEXT: movabsq $0, %r11 ; X64-NEXT: callq __morestack -; X64-NEXT: movq %rax, %r10 ; X64-NEXT: ret +; X64: movq %rax, %r10 } |