diff options
| -rw-r--r-- | lib/Target/X86/X86FrameLowering.cpp | 6 | ||||
| -rw-r--r-- | test/CodeGen/X86/compact-unwind.ll | 30 |
2 files changed, 36 insertions, 0 deletions
diff --git a/lib/Target/X86/X86FrameLowering.cpp b/lib/Target/X86/X86FrameLowering.cpp index ae51178f73..42b4e73509 100644 --- a/lib/Target/X86/X86FrameLowering.cpp +++ b/lib/Target/X86/X86FrameLowering.cpp @@ -525,6 +525,12 @@ uint32_t X86FrameLowering::getCompactUnwindEncoding(MachineFunction &MF) const { // If there are too many saved registers, we cannot use compact encoding. if (SavedRegIdx >= CU_NUM_SAVED_REGS) return CU::UNWIND_MODE_DWARF; + unsigned Reg = MI.getOperand(0).getReg(); + if (Reg == (Is64Bit ? X86::RAX : X86::EAX)) { + ExpectEnd = true; + continue; + } + SavedRegs[SavedRegIdx++] = MI.getOperand(0).getReg(); StackAdjust += OffsetSize; InstrOffset += PushInstrSize; diff --git a/test/CodeGen/X86/compact-unwind.ll b/test/CodeGen/X86/compact-unwind.ll new file mode 100644 index 0000000000..8c4fa27da5 --- /dev/null +++ b/test/CodeGen/X86/compact-unwind.ll @@ -0,0 +1,30 @@ +; RUN: llc < %s -disable-cfi -disable-fp-elim -mtriple x86_64-apple-darwin11 | FileCheck %s + +%ty = type { i8* } + +@gv = external global i32 + +; This is aligning the stack with a push of a random register. +; CHECK: pushq %rax + +; Even though we can't encode %rax into the compact unwind, We still want to be +; able to generate a compact unwind encoding in this particular case. +; +; CHECK: __LD,__compact_unwind +; CHECK: _foo ## Range Start +; CHECK: 16842753 ## Compact Unwind Encoding: 0x1010001 + +define i8* @foo(i64 %size) { + %addr = alloca i64, align 8 + %tmp20 = load i32* @gv, align 4 + %tmp21 = call i32 @bar() + %tmp25 = load i64* %addr, align 8 + %tmp26 = inttoptr i64 %tmp25 to %ty* + %tmp29 = getelementptr inbounds %ty* %tmp26, i64 0, i32 0 + %tmp34 = load i8** %tmp29, align 8 + %tmp35 = getelementptr inbounds i8* %tmp34, i64 %size + store i8* %tmp35, i8** %tmp29, align 8 + ret i8* null +} + +declare i32 @bar() |