Method GetDbgBreakKind

IDEHelper/X64.cpp:995–1079

}

DbgBreakKind X64CPU::GetDbgBreakKind(uint64 address, DbgModuleMemoryCache* memoryCache, int64* regs, int64* outObjectPtr)
{
	// We've looking for a CMP BYTE PTR [<reg>], -0x80
	//  if <reg> is R12 then encoding takes an extra 2 bytes
	X64Instr inst;
	for (int checkLen = 5; checkLen >= 3; checkLen--)
	{
		int offset = -3 - checkLen;

		if (!Decode(address + offset, memoryCache, &inst))
			continue;

		if (inst.GetLength() != checkLen)
			continue;

		const MCInstrDesc &instDesc = mInstrInfo->get(inst.mMCInst.getOpcode());
		if (!instDesc.isCompare())
			continue;

		auto immediateType = (instDesc.TSFlags & llvm::X86II::ImmMask);
		if ((immediateType == llvm::X86II::Imm8) && (inst.mMCInst.getNumOperands() == 2))
		{
			// We're checking for a TEST [<reg>], 1
			if (inst.mMCInst.getOpcode() != llvm::X86::TEST8ri)
				continue;
			auto immOp = inst.mMCInst.getOperand(1);
			if (!immOp.isImm())
				continue;
			if (immOp.getImm() != 1)
				continue;
			return DbgBreakKind_ArithmeticOverflow;
		}

		if ((immediateType == 0) || (inst.mMCInst.getNumOperands() < 6))
			continue;

		auto form = (instDesc.TSFlags & llvm::X86II::FormMask);

		auto baseReg = inst.mMCInst.getOperand(llvm::X86::AddrBaseReg);
		/*auto scaleAmt = inst.mMCInst.getOperand(llvm::X86::AddrScaleAmt);
		auto indexReg = inst.mMCInst.getOperand(llvm::X86::AddrIndexReg);
		auto addrDisp = inst.mMCInst.getOperand(llvm::X86::AddrDisp);*/

		auto immOp = inst.mMCInst.getOperand(5);
		if (!immOp.isImm())
			continue;
		if (immOp.getImm() != -0x80)
			continue;

		int regNum = ConvertRegNum(baseReg);
		if (regNum == -1)
			continue;

		*outObjectPtr = (uint64)regs[regNum];

		return DbgBreakKind_ObjectAccess;
	}