uint8_t *TR::X86FPConvertToIntSnippet::genFPConversion(uint8_t *buffer)
{
TR::ILOpCodes opcode = _convertInstruction->getNode()->getOpCodeValue();
TR::RealRegister *targetRegister = toRealRegister(_convertInstruction->getTargetRegister());
TR::RealRegister::RegNum targetReg = targetRegister->getRegisterNumber();
TR::Machine *machine = cg()->machine();
TR_ASSERT(cg()->getProperties().getIntegerReturnRegister() == TR::RealRegister::eax, "Only support integer return in eax");
if (targetReg != TR::RealRegister::eax)
{
// MOV R, eax
//
*buffer++ = 0x8b;
*buffer = 0xc0;
targetRegister->setRegisterFieldInModRM(buffer);
buffer++;
}
// Push the floating-point value on to the stack before calling the helper.
//
// SUB esp, 4/8
//
*buffer++ = 0x83;
*buffer++ = 0xec;
if (opcode == TR::f2i)
*buffer++ = 0x04;
else
*buffer++ = 0x08;
if (_convertInstruction->getIA32RegMemInstruction())
{
// FST [esp], st0
//
if (opcode == TR::f2i)
*buffer++ = 0xd9;
else
*buffer++ = 0xdd;
*buffer++ = 0x14;
*buffer++ = 0x24;
}
else
{
TR::X86RegRegInstruction *instr = _convertInstruction->getIA32RegRegInstruction();
TR_ASSERT(instr != NULL, "f2i conversion instruction must be either L4RegMem or CVTTSS2SIRegReg\n");
TR::RealRegister *sourceRegister = toRealRegister(instr->getSourceRegister());
// MOVSS/MOVSD [esp], source
//
if (opcode == TR::f2i)
*buffer++ = 0xf3;
else
*buffer++ = 0xf2;
*buffer++ = 0x0f;
*buffer++ = 0x11;
*buffer = 0x04;
sourceRegister->setRegisterFieldInModRM(buffer);
buffer++;
*buffer++ = 0x24;
}
// Call the helper
//
buffer = emitCallToConversionHelper(buffer);
// ADD esp, 4/8
//
*buffer++ = 0x83;
*buffer++ = 0xc4;
if (opcode == TR::f2i)
*buffer++ = 0x04;
else
*buffer++ = 0x08;
if (targetReg != TR::RealRegister::eax)
{
// XCHG R, eax
//
*buffer = 0x90;
targetRegister->setRegisterFieldInOpcode(buffer);
buffer++;
}
return buffer;
}
uint8_t *TR::AMD64FPConversionSnippet::genFPConversion(uint8_t *buffer)
{
// *this swipeable for debugging purposes
// This didn't end up as clean as I thought. TODO:AMD64: Separate out the 64-bit code into another class.
TR::ILOpCodes opCode = _convertInstruction->getNode()->getOpCodeValue();
TR::RealRegister *targetRegister = toRealRegister(_convertInstruction->getTargetRegister());
TR::RealRegister::RegNum targetReg = targetRegister->getRegisterNumber();
TR::Machine *machine = cg()->machine();
const TR::X86LinkageProperties &properties = cg()->getProperties();
uint8_t *originalBuffer = buffer;
TR_ASSERT(properties.getIntegerReturnRegister() == TR::RealRegister::eax, "Only support integer return in eax");
if (targetReg != TR::RealRegister::eax)
{
// MOV R, rax
//
*buffer++ = TR::RealRegister::REX | TR::RealRegister::REX_W | targetRegister->rexBits(TR::RealRegister::REX_R, false);
*buffer++ = 0x8b;
*buffer = 0xc0;
targetRegister->setRegisterFieldInModRM(buffer);
buffer++;
}
TR_ASSERT(properties.getFloatArgumentRegister(0) == TR::RealRegister::xmm0, "Only support 1st FP arg in xmm0");
TR::X86RegRegInstruction *instr = _convertInstruction->getIA32RegRegInstruction();
TR_ASSERT(instr != NULL, "conversion instruction must be CVTTSS2SIRegReg\n");
TR::RealRegister *sourceRegister = toRealRegister(instr->getSourceRegister());
TR::RealRegister::RegNum sourceReg = sourceRegister->getRegisterNumber();
// Save xmm0 if necessary
//
if (sourceReg != TR::RealRegister::xmm0)
{
TR_ASSERT(TR::Compiler->target.is64Bit(), "This push sequence only works on AMD64");
memcpy(buffer, pushBinary, sizeof(pushBinary));
buffer += sizeof(pushBinary);
// MOVSD xmm0, source
//
*buffer++ = 0xf2;
if( (*buffer = sourceRegister->rexBits(TR::RealRegister::REX_B, false)) )
buffer++;
*buffer++ = 0x0f;
*buffer++ = 0x10;
*buffer = 0xc0;
sourceRegister->setRegisterFieldInOpcode(buffer);
buffer++;
}
// Call the helper
//
buffer = emitCallToConversionHelper(buffer);
// Restore xmm0 if necessary
//
if (sourceReg != TR::RealRegister::xmm0)
{
TR_ASSERT(TR::Compiler->target.is64Bit(), "This pop sequence only works on AMD64");
memcpy(buffer, popBinary, sizeof(popBinary));
buffer += sizeof(popBinary);
}
if (targetReg != TR::RealRegister::eax)
{
// XCHG R, rax
//
*buffer++ = TR::RealRegister::REX | TR::RealRegister::REX_W | targetRegister->rexBits(TR::RealRegister::REX_B, false);
*buffer = 0x90;
targetRegister->setRegisterFieldInOpcode(buffer);
buffer++;
}
return buffer;
}
