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Differential D45471

ShadowCallStack/x86_64: Ignore pseudo-machine instructions
ClosedPublic

Authored by vlad.tsyrklevich on Apr 9 2018, 6:27 PM.

Details

Reviewers
pcc
Summary

TBR for a trivial bug fix

Diff Detail

Revision Contents

PathSize
lib/
Target/
X86/
3 lines
test/
CodeGen/
X86/
8 lines

Diff 141777

lib/Target/X86/ShadowCallStack.cpp

Show First 20 Lines • Show All 236 Lines • ▼ Show 20 Linesbool ShadowCallStack::runOnMachineFunction(MachineFunction &Fn) {
MCPhysReg LeafFuncRegister = X86::NoRegister; MCPhysReg LeafFuncRegister = X86::NoRegister;
if (!Fn.getFrameInfo().adjustsStack()) { if (!Fn.getFrameInfo().adjustsStack()) {
size_t InstructionCount = 0; size_t InstructionCount = 0;
std::bitset<X86::NUM_TARGET_REGS> UsedRegs; std::bitset<X86::NUM_TARGET_REGS> UsedRegs;
for (auto &MBB : Fn) { for (auto &MBB : Fn) {
for (auto &LiveIn : MBB.liveins()) for (auto &LiveIn : MBB.liveins())
UsedRegs.set(LiveIn.PhysReg); UsedRegs.set(LiveIn.PhysReg);
for (auto &MI : MBB) { for (auto &MI : MBB) {
if (!MI.isDebugValue() && !MI.isCFIInstruction() && !MI.isLabel())
InstructionCount++; InstructionCount++;
for (auto &Op : MI.operands()) for (auto &Op : MI.operands())
if (Op.isReg() && Op.isDef()) if (Op.isReg() && Op.isDef())
UsedRegs.set(Op.getReg()); UsedRegs.set(Op.getReg());
} }
} }
if (InstructionCount <= SkipLeafInstructions) if (InstructionCount <= SkipLeafInstructions)
return false; return false;
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test/CodeGen/X86/shadow-call-stack.mir

Show First 20 Lines • Show All 100 Lines • ▼ Show 20 Lines
# CHECK-LABEL: name: short_leaf_func # CHECK-LABEL: name: short_leaf_func
name: short_leaf_func name: short_leaf_func
tracksRegLiveness: true tracksRegLiveness: true
frameInfo: frameInfo:
adjustsStack: false # leaf function adjustsStack: false # leaf function
body: | body: |
; CHECK: bb.0: ; CHECK: bb.0:
bb.0: bb.0:
; Ensure these are not counted as machine instructions
CFI_INSTRUCTION 0
CFI_INSTRUCTION 0
CFI_INSTRUCTION 0
DBG_VALUE 0
DBG_VALUE 0
DBG_VALUE 0
; CHECK: $eax = MOV32ri 13 ; CHECK: $eax = MOV32ri 13
$eax = MOV32ri 13 $eax = MOV32ri 13
; CHECK-NEXT: RETQ $eax ; CHECK-NEXT: RETQ $eax
RETQ $eax RETQ $eax
... ...
--- ---
# CHECK-LABEL: name: normal_tail_call # CHECK-LABEL: name: normal_tail_call
▲ Show 20 Lines • Show All 88 Lines • Show Last 20 Lines