#include "llvm/MC/MCTargetOptions.h"
#include "llvm/Support/CommandLine.h"
#include <algorithm>
+#include <cassert>
+#include <vector>
namespace llvm {
namespace {
class X86AddressSanitizer : public X86AsmInstrumentation {
public:
struct RegisterContext {
+ private:
+ enum RegOffset {
+ REG_OFFSET_ADDRESS = 0,
+ REG_OFFSET_SHADOW,
+ REG_OFFSET_SCRATCH
+ };
+
+ public:
RegisterContext(unsigned AddressReg, unsigned ShadowReg,
- unsigned ScratchReg)
- : AddressReg(AddressReg), ShadowReg(ShadowReg), ScratchReg(ScratchReg) {
+ unsigned ScratchReg) {
+ for (unsigned Reg : { AddressReg, ShadowReg, ScratchReg }) {
+ BusyRegs.push_back(convReg(Reg, MVT::i64));
+ }
+ }
+
+ unsigned AddressReg(MVT::SimpleValueType VT) const {
+ return convReg(BusyRegs[REG_OFFSET_ADDRESS], VT);
+ }
+
+ unsigned ShadowReg(MVT::SimpleValueType VT) const {
+ return convReg(BusyRegs[REG_OFFSET_SHADOW], VT);
+ }
+
+ unsigned ScratchReg(MVT::SimpleValueType VT) const {
+ return convReg(BusyRegs[REG_OFFSET_SCRATCH], VT);
+ }
+
+ void AddBusyReg(unsigned Reg) {
+ if (Reg != X86::NoRegister)
+ BusyRegs.push_back(convReg(Reg, MVT::i64));
}
- unsigned addressReg(MVT::SimpleValueType VT) const {
- return getX86SubSuperRegister(AddressReg, VT);
+ void AddBusyRegs(const X86Operand &Op) {
+ AddBusyReg(Op.getMemBaseReg());
+ AddBusyReg(Op.getMemIndexReg());
}
- unsigned shadowReg(MVT::SimpleValueType VT) const {
- return getX86SubSuperRegister(ShadowReg, VT);
+ unsigned ChooseFrameReg(MVT::SimpleValueType VT) const {
+ static const unsigned Candidates[] = { X86::RBP, X86::RAX, X86::RBX,
+ X86::RCX, X86::RDX, X86::RDI,
+ X86::RSI };
+ for (unsigned Reg : Candidates) {
+ if (!std::count(BusyRegs.begin(), BusyRegs.end(), Reg))
+ return convReg(Reg, VT);
+ }
+ return X86::NoRegister;
}
- unsigned scratchReg(MVT::SimpleValueType VT) const {
- return getX86SubSuperRegister(ScratchReg, VT);
+ private:
+ unsigned convReg(unsigned Reg, MVT::SimpleValueType VT) const {
+ return Reg == X86::NoRegister ? Reg : getX86SubSuperRegister(Reg, VT);
}
- const unsigned AddressReg;
- const unsigned ShadowReg;
- const unsigned ScratchReg;
+ std::vector<unsigned> BusyRegs;
};
X86AddressSanitizer(const MCSubtargetInfo &STI)
IsSmallMemAccess(AccessSize)
? X86::RBX
: X86::NoRegister /* ScratchReg */);
+ RegCtx.AddBusyReg(DstReg);
+ RegCtx.AddBusyReg(SrcReg);
+ RegCtx.AddBusyReg(CntReg);
InstrumentMemOperandPrologue(RegCtx, Ctx, Out);
}
const bool IsWrite = MII.get(Inst.getOpcode()).mayStore();
- RegisterContext RegCtx(X86::RDI /* AddressReg */, X86::RAX /* ShadowReg */,
- IsSmallMemAccess(AccessSize)
- ? X86::RCX
- : X86::NoRegister /* ScratchReg */);
for (unsigned Ix = 0; Ix < Operands.size(); ++Ix) {
assert(Operands[Ix]);
MCParsedAsmOperand &Op = *Operands[Ix];
if (Op.isMem()) {
X86Operand &MemOp = static_cast<X86Operand &>(Op);
+ RegisterContext RegCtx(
+ X86::RDI /* AddressReg */, X86::RAX /* ShadowReg */,
+ IsSmallMemAccess(AccessSize) ? X86::RCX
+ : X86::NoRegister /* ScratchReg */);
+ RegCtx.AddBusyRegs(MemOp);
InstrumentMemOperandPrologue(RegCtx, Ctx, Out);
InstrumentMemOperand(MemOp, AccessSize, IsWrite, RegCtx, Ctx, Out);
InstrumentMemOperandEpilogue(RegCtx, Ctx, Out);
virtual void InstrumentMemOperandPrologue(const RegisterContext &RegCtx,
MCContext &Ctx,
MCStreamer &Out) override {
+ unsigned LocalFrameReg = RegCtx.ChooseFrameReg(MVT::i32);
+ assert(LocalFrameReg != X86::NoRegister);
+
const MCRegisterInfo *MRI = Ctx.getRegisterInfo();
unsigned FrameReg = GetFrameReg(Ctx, Out);
if (MRI && FrameReg != X86::NoRegister) {
- SpillReg(Out, X86::EBP);
+ SpillReg(Out, LocalFrameReg);
if (FrameReg == X86::ESP) {
- Out.EmitCFIAdjustCfaOffset(4 /* byte size of the FrameReg */);
- Out.EmitCFIRelOffset(MRI->getDwarfRegNum(X86::EBP, true /* IsEH */), 0);
+ Out.EmitCFIAdjustCfaOffset(4 /* byte size of the LocalFrameReg */);
+ Out.EmitCFIRelOffset(
+ MRI->getDwarfRegNum(LocalFrameReg, true /* IsEH */), 0);
}
EmitInstruction(
- Out, MCInstBuilder(X86::MOV32rr).addReg(X86::EBP).addReg(FrameReg));
+ Out,
+ MCInstBuilder(X86::MOV32rr).addReg(LocalFrameReg).addReg(FrameReg));
Out.EmitCFIRememberState();
- Out.EmitCFIDefCfaRegister(MRI->getDwarfRegNum(X86::EBP, true /* IsEH */));
+ Out.EmitCFIDefCfaRegister(
+ MRI->getDwarfRegNum(LocalFrameReg, true /* IsEH */));
}
- SpillReg(Out, RegCtx.addressReg(MVT::i32));
- SpillReg(Out, RegCtx.shadowReg(MVT::i32));
- if (RegCtx.ScratchReg != X86::NoRegister)
- SpillReg(Out, RegCtx.scratchReg(MVT::i32));
+ SpillReg(Out, RegCtx.AddressReg(MVT::i32));
+ SpillReg(Out, RegCtx.ShadowReg(MVT::i32));
+ if (RegCtx.ScratchReg(MVT::i32) != X86::NoRegister)
+ SpillReg(Out, RegCtx.ScratchReg(MVT::i32));
StoreFlags(Out);
}
virtual void InstrumentMemOperandEpilogue(const RegisterContext &RegCtx,
MCContext &Ctx,
MCStreamer &Out) override {
+ unsigned LocalFrameReg = RegCtx.ChooseFrameReg(MVT::i32);
+ assert(LocalFrameReg != X86::NoRegister);
+
RestoreFlags(Out);
- if (RegCtx.ScratchReg != X86::NoRegister)
- RestoreReg(Out, RegCtx.scratchReg(MVT::i32));
- RestoreReg(Out, RegCtx.shadowReg(MVT::i32));
- RestoreReg(Out, RegCtx.addressReg(MVT::i32));
+ if (RegCtx.ScratchReg(MVT::i32) != X86::NoRegister)
+ RestoreReg(Out, RegCtx.ScratchReg(MVT::i32));
+ RestoreReg(Out, RegCtx.ShadowReg(MVT::i32));
+ RestoreReg(Out, RegCtx.AddressReg(MVT::i32));
unsigned FrameReg = GetFrameReg(Ctx, Out);
if (Ctx.getRegisterInfo() && FrameReg != X86::NoRegister) {
- RestoreReg(Out, X86::EBP);
+ RestoreReg(Out, LocalFrameReg);
Out.EmitCFIRestoreState();
if (FrameReg == X86::ESP)
- Out.EmitCFIAdjustCfaOffset(-4 /* byte size of the FrameReg */);
+ Out.EmitCFIAdjustCfaOffset(-4 /* byte size of the LocalFrameReg */);
}
}
.addReg(X86::ESP)
.addImm(-16));
EmitInstruction(
- Out, MCInstBuilder(X86::PUSH32r).addReg(RegCtx.addressReg(MVT::i32)));
+ Out, MCInstBuilder(X86::PUSH32r).addReg(RegCtx.AddressReg(MVT::i32)));
const std::string &Fn = FuncName(AccessSize, IsWrite);
MCSymbol *FnSym = Ctx.GetOrCreateSymbol(StringRef(Fn));
void X86AddressSanitizer32::InstrumentMemOperandSmall(
X86Operand &Op, unsigned AccessSize, bool IsWrite,
const RegisterContext &RegCtx, MCContext &Ctx, MCStreamer &Out) {
- unsigned AddressRegI32 = RegCtx.addressReg(MVT::i32);
- unsigned ShadowRegI32 = RegCtx.shadowReg(MVT::i32);
- unsigned ShadowRegI8 = RegCtx.shadowReg(MVT::i8);
+ unsigned AddressRegI32 = RegCtx.AddressReg(MVT::i32);
+ unsigned ShadowRegI32 = RegCtx.ShadowReg(MVT::i32);
+ unsigned ShadowRegI8 = RegCtx.ShadowReg(MVT::i8);
- assert(RegCtx.ScratchReg != X86::NoRegister);
- unsigned ScratchRegI32 = RegCtx.scratchReg(MVT::i32);
+ assert(RegCtx.ScratchReg(MVT::i32) != X86::NoRegister);
+ unsigned ScratchRegI32 = RegCtx.ScratchReg(MVT::i32);
ComputeMemOperandAddress(Op, MVT::i32, AddressRegI32, Ctx, Out);
void X86AddressSanitizer32::InstrumentMemOperandLarge(
X86Operand &Op, unsigned AccessSize, bool IsWrite,
const RegisterContext &RegCtx, MCContext &Ctx, MCStreamer &Out) {
- unsigned AddressRegI32 = RegCtx.addressReg(MVT::i32);
- unsigned ShadowRegI32 = RegCtx.shadowReg(MVT::i32);
+ unsigned AddressRegI32 = RegCtx.AddressReg(MVT::i32);
+ unsigned ShadowRegI32 = RegCtx.ShadowReg(MVT::i32);
ComputeMemOperandAddress(Op, MVT::i32, AddressRegI32, Ctx, Out);
virtual void InstrumentMemOperandPrologue(const RegisterContext &RegCtx,
MCContext &Ctx,
MCStreamer &Out) override {
+ unsigned LocalFrameReg = RegCtx.ChooseFrameReg(MVT::i64);
+ assert(LocalFrameReg != X86::NoRegister);
+
const MCRegisterInfo *MRI = Ctx.getRegisterInfo();
unsigned FrameReg = GetFrameReg(Ctx, Out);
if (MRI && FrameReg != X86::NoRegister) {
SpillReg(Out, X86::RBP);
if (FrameReg == X86::RSP) {
- Out.EmitCFIAdjustCfaOffset(8 /* byte size of the FrameReg */);
- Out.EmitCFIRelOffset(MRI->getDwarfRegNum(X86::RBP, true /* IsEH */), 0);
+ Out.EmitCFIAdjustCfaOffset(8 /* byte size of the LocalFrameReg */);
+ Out.EmitCFIRelOffset(
+ MRI->getDwarfRegNum(LocalFrameReg, true /* IsEH */), 0);
}
EmitInstruction(
- Out, MCInstBuilder(X86::MOV64rr).addReg(X86::RBP).addReg(FrameReg));
+ Out,
+ MCInstBuilder(X86::MOV64rr).addReg(LocalFrameReg).addReg(FrameReg));
Out.EmitCFIRememberState();
- Out.EmitCFIDefCfaRegister(MRI->getDwarfRegNum(X86::RBP, true /* IsEH */));
+ Out.EmitCFIDefCfaRegister(
+ MRI->getDwarfRegNum(LocalFrameReg, true /* IsEH */));
}
EmitAdjustRSP(Ctx, Out, -128);
- SpillReg(Out, RegCtx.shadowReg(MVT::i64));
- SpillReg(Out, RegCtx.addressReg(MVT::i64));
- if (RegCtx.ScratchReg != X86::NoRegister)
- SpillReg(Out, RegCtx.scratchReg(MVT::i64));
+ SpillReg(Out, RegCtx.ShadowReg(MVT::i64));
+ SpillReg(Out, RegCtx.AddressReg(MVT::i64));
+ if (RegCtx.ScratchReg(MVT::i64) != X86::NoRegister)
+ SpillReg(Out, RegCtx.ScratchReg(MVT::i64));
StoreFlags(Out);
}
virtual void InstrumentMemOperandEpilogue(const RegisterContext &RegCtx,
MCContext &Ctx,
MCStreamer &Out) override {
+ unsigned LocalFrameReg = RegCtx.ChooseFrameReg(MVT::i64);
+ assert(LocalFrameReg != X86::NoRegister);
+
RestoreFlags(Out);
- if (RegCtx.ScratchReg != X86::NoRegister)
- RestoreReg(Out, RegCtx.scratchReg(MVT::i64));
- RestoreReg(Out, RegCtx.addressReg(MVT::i64));
- RestoreReg(Out, RegCtx.shadowReg(MVT::i64));
+ if (RegCtx.ScratchReg(MVT::i64) != X86::NoRegister)
+ RestoreReg(Out, RegCtx.ScratchReg(MVT::i64));
+ RestoreReg(Out, RegCtx.AddressReg(MVT::i64));
+ RestoreReg(Out, RegCtx.ShadowReg(MVT::i64));
EmitAdjustRSP(Ctx, Out, 128);
unsigned FrameReg = GetFrameReg(Ctx, Out);
if (Ctx.getRegisterInfo() && FrameReg != X86::NoRegister) {
- RestoreReg(Out, X86::RBP);
+ RestoreReg(Out, LocalFrameReg);
Out.EmitCFIRestoreState();
if (FrameReg == X86::RSP)
- Out.EmitCFIAdjustCfaOffset(-8 /* byte size of the FrameReg */);
+ Out.EmitCFIAdjustCfaOffset(-8 /* byte size of the LocalFrameReg */);
}
}
.addReg(X86::RSP)
.addImm(-16));
- if (RegCtx.AddressReg != X86::RDI) {
+ if (RegCtx.AddressReg(MVT::i64) != X86::RDI) {
EmitInstruction(Out, MCInstBuilder(X86::MOV64rr).addReg(X86::RDI).addReg(
- RegCtx.addressReg(MVT::i64)));
+ RegCtx.AddressReg(MVT::i64)));
}
const std::string &Fn = FuncName(AccessSize, IsWrite);
MCSymbol *FnSym = Ctx.GetOrCreateSymbol(StringRef(Fn));
void X86AddressSanitizer64::InstrumentMemOperandSmall(
X86Operand &Op, unsigned AccessSize, bool IsWrite,
const RegisterContext &RegCtx, MCContext &Ctx, MCStreamer &Out) {
- unsigned AddressRegI64 = RegCtx.addressReg(MVT::i64);
- unsigned AddressRegI32 = RegCtx.addressReg(MVT::i32);
- unsigned ShadowRegI64 = RegCtx.shadowReg(MVT::i64);
- unsigned ShadowRegI32 = RegCtx.shadowReg(MVT::i32);
- unsigned ShadowRegI8 = RegCtx.shadowReg(MVT::i8);
+ unsigned AddressRegI64 = RegCtx.AddressReg(MVT::i64);
+ unsigned AddressRegI32 = RegCtx.AddressReg(MVT::i32);
+ unsigned ShadowRegI64 = RegCtx.ShadowReg(MVT::i64);
+ unsigned ShadowRegI32 = RegCtx.ShadowReg(MVT::i32);
+ unsigned ShadowRegI8 = RegCtx.ShadowReg(MVT::i8);
- assert(RegCtx.ScratchReg != X86::NoRegister);
- unsigned ScratchRegI32 = RegCtx.scratchReg(MVT::i32);
+ assert(RegCtx.ScratchReg(MVT::i32) != X86::NoRegister);
+ unsigned ScratchRegI32 = RegCtx.ScratchReg(MVT::i32);
ComputeMemOperandAddress(Op, MVT::i64, AddressRegI64, Ctx, Out);
void X86AddressSanitizer64::InstrumentMemOperandLarge(
X86Operand &Op, unsigned AccessSize, bool IsWrite,
const RegisterContext &RegCtx, MCContext &Ctx, MCStreamer &Out) {
- unsigned AddressRegI64 = RegCtx.addressReg(MVT::i64);
- unsigned ShadowRegI64 = RegCtx.shadowReg(MVT::i64);
+ unsigned AddressRegI64 = RegCtx.AddressReg(MVT::i64);
+ unsigned ShadowRegI64 = RegCtx.ShadowReg(MVT::i64);
ComputeMemOperandAddress(Op, MVT::i64, AddressRegI64, Ctx, Out);