pcsx2/common/emitter/simd.cpp

// SPDX-FileCopyrightText: 2002-2023 PCSX2 Dev Team
// SPDX-License-Identifier: LGPL-3.0+

#include "common/emitter/internal.h"
#include "common/VectorIntrin.h"

namespace x86Emitter
{

	// ------------------------------------------------------------------------
	// SimdPrefix - If the lower byte of the opcode is 0x38 or 0x3a, then the opcode is
	// treated as a 16 bit value (in SSE 0x38 and 0x3a denote prefixes for extended SSE3/4
	// instructions).  Any other lower value assumes the upper value is 0 and ignored.
	// Non-zero upper bytes, when the lower byte is not the 0x38 or 0x3a prefix, will
	// generate an assertion.
	//
	__emitinline void SimdPrefix(u8 prefix, u16 opcode)
	{
		pxAssertMsg(prefix == 0, "REX prefix must be just before the opcode");

		const bool is16BitOpcode = ((opcode & 0xff) == 0x38) || ((opcode & 0xff) == 0x3a);

		// If the lower byte is not a valid prefix and the upper byte is non-zero it
		// means we made a mistake!
		if (!is16BitOpcode)
			pxAssert((opcode >> 8) == 0);

		if (prefix != 0)
		{
			if (is16BitOpcode)
				xWrite32((opcode << 16) | 0x0f00 | prefix);
			else
			{
				xWrite16(0x0f00 | prefix);
				xWrite8(opcode);
			}
		}
		else
		{
			if (is16BitOpcode)
			{
				xWrite8(0x0f);
				xWrite16(opcode);
			}
			else
				xWrite16((opcode << 8) | 0x0f);
		}
	}

	const xImplSimd_DestRegEither xPAND = {0x66, 0xdb};
	const xImplSimd_DestRegEither xPANDN = {0x66, 0xdf};
	const xImplSimd_DestRegEither xPOR = {0x66, 0xeb};
	const xImplSimd_DestRegEither xPXOR = {0x66, 0xef};

	// [SSE-4.1] Performs a bitwise AND of dest against src, and sets the ZF flag
	// only if all bits in the result are 0.  PTEST also sets the CF flag according
	// to the following condition: (xmm2/m128 AND NOT xmm1) == 0;
	const xImplSimd_DestRegSSE xPTEST = {0x66, 0x1738};

	// =====================================================================================================
	// SSE Conversion Operations, as looney as they are.
	// =====================================================================================================
	// These enforce pointer strictness for Indirect forms, due to the otherwise completely confusing
	// nature of the functions.  (so if a function expects an m32, you must use (u32*) or ptr32[]).
	//

	__fi void xCVTDQ2PD(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0xf3, 0xe6); }
	__fi void xCVTDQ2PD(const xRegisterSSE& to, const xIndirect64& from) { OpWriteSSE(0xf3, 0xe6); }
	__fi void xCVTDQ2PS(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0x00, 0x5b); }
	__fi void xCVTDQ2PS(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0x00, 0x5b); }

	__fi void xCVTPD2DQ(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0xf2, 0xe6); }
	__fi void xCVTPD2DQ(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0xf2, 0xe6); }
	__fi void xCVTPD2PS(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0x66, 0x5a); }
	__fi void xCVTPD2PS(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0x66, 0x5a); }

	__fi void xCVTPI2PD(const xRegisterSSE& to, const xIndirect64& from) { OpWriteSSE(0x66, 0x2a); }
	__fi void xCVTPI2PS(const xRegisterSSE& to, const xIndirect64& from) { OpWriteSSE(0x00, 0x2a); }

	__fi void xCVTPS2DQ(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0x66, 0x5b); }
	__fi void xCVTPS2DQ(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0x66, 0x5b); }
	__fi void xCVTPS2PD(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0x00, 0x5a); }
	__fi void xCVTPS2PD(const xRegisterSSE& to, const xIndirect64& from) { OpWriteSSE(0x00, 0x5a); }

	__fi void xCVTSD2SI(const xRegister32or64& to, const xRegisterSSE& from) { OpWriteSSE(0xf2, 0x2d); }
	__fi void xCVTSD2SI(const xRegister32or64& to, const xIndirect64& from) { OpWriteSSE(0xf2, 0x2d); }
	__fi void xCVTSD2SS(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0xf2, 0x5a); }
	__fi void xCVTSD2SS(const xRegisterSSE& to, const xIndirect64& from) { OpWriteSSE(0xf2, 0x5a); }
	__fi void xCVTSI2SS(const xRegisterSSE& to, const xRegister32or64& from) { OpWriteSSE(0xf3, 0x2a); }
	__fi void xCVTSI2SS(const xRegisterSSE& to, const xIndirect32& from) { OpWriteSSE(0xf3, 0x2a); }

	__fi void xCVTSS2SD(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0xf3, 0x5a); }
	__fi void xCVTSS2SD(const xRegisterSSE& to, const xIndirect32& from) { OpWriteSSE(0xf3, 0x5a); }
	__fi void xCVTSS2SI(const xRegister32or64& to, const xRegisterSSE& from) { OpWriteSSE(0xf3, 0x2d); }
	__fi void xCVTSS2SI(const xRegister32or64& to, const xIndirect32& from) { OpWriteSSE(0xf3, 0x2d); }

	__fi void xCVTTPD2DQ(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0x66, 0xe6); }
	__fi void xCVTTPD2DQ(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0x66, 0xe6); }
	__fi void xCVTTPS2DQ(const xRegisterSSE& to, const xRegisterSSE& from) { OpWriteSSE(0xf3, 0x5b); }
	__fi void xCVTTPS2DQ(const xRegisterSSE& to, const xIndirect128& from) { OpWriteSSE(0xf3, 0x5b); }

	__fi void xCVTTSD2SI(const xRegister32or64& to, const xRegisterSSE& from) { OpWriteSSE(0xf2, 0x2c); }
	__fi void xCVTTSD2SI(const xRegister32or64& to, const xIndirect64& from) { OpWriteSSE(0xf2, 0x2c); }
	__fi void xCVTTSS2SI(const xRegister32or64& to, const xRegisterSSE& from) { OpWriteSSE(0xf3, 0x2c); }
	__fi void xCVTTSS2SI(const xRegister32or64& to, const xIndirect32& from) { OpWriteSSE(0xf3, 0x2c); }


	// ------------------------------------------------------------------------

	void xImplSimd_DestRegSSE::operator()(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(Prefix, Opcode); }
	void xImplSimd_DestRegSSE::operator()(const xRegisterSSE& to, const xIndirectVoid& from) const { OpWriteSSE(Prefix, Opcode); }

	void xImplSimd_DestRegImmSSE::operator()(const xRegisterSSE& to, const xRegisterSSE& from, u8 imm) const { xOpWrite0F(Prefix, Opcode, to, from, imm); }
	void xImplSimd_DestRegImmSSE::operator()(const xRegisterSSE& to, const xIndirectVoid& from, u8 imm) const { xOpWrite0F(Prefix, Opcode, to, from, imm); }


	void xImplSimd_DestRegEither::operator()(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(Prefix, Opcode); }
	void xImplSimd_DestRegEither::operator()(const xRegisterSSE& to, const xIndirectVoid& from) const { OpWriteSSE(Prefix, Opcode); }


	void xImplSimd_DestSSE_CmpImm::operator()(const xRegisterSSE& to, const xRegisterSSE& from, SSE2_ComparisonType imm) const { xOpWrite0F(Prefix, Opcode, to, from, imm); }
	void xImplSimd_DestSSE_CmpImm::operator()(const xRegisterSSE& to, const xIndirectVoid& from, SSE2_ComparisonType imm) const { xOpWrite0F(Prefix, Opcode, to, from, imm); }

	// =====================================================================================================
	//  SIMD Arithmetic Instructions
	// =====================================================================================================

	void _SimdShiftHelper::operator()(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(Prefix, Opcode); }
	void _SimdShiftHelper::operator()(const xRegisterSSE& to, const xIndirectVoid& from) const { OpWriteSSE(Prefix, Opcode); }


	void _SimdShiftHelper::operator()(const xRegisterSSE& to, u8 imm8) const
	{
		xOpWrite0F(0x66, OpcodeImm, (int)Modcode, to);
		xWrite8(imm8);
	}

	void xImplSimd_Shift::DQ(const xRegisterSSE& to, u8 imm8) const
	{
		xOpWrite0F(0x66, 0x73, (int)Q.Modcode + 1, to, imm8);
	}


	const xImplSimd_ShiftWithoutQ xPSRA =
		{
			{0x66, 0xe1, 0x71, 4}, // W
			{0x66, 0xe2, 0x72, 4} // D
	};

	const xImplSimd_Shift xPSRL =
		{
			{0x66, 0xd1, 0x71, 2}, // W
			{0x66, 0xd2, 0x72, 2}, // D
			{0x66, 0xd3, 0x73, 2}, // Q
	};

	const xImplSimd_Shift xPSLL =
		{
			{0x66, 0xf1, 0x71, 6}, // W
			{0x66, 0xf2, 0x72, 6}, // D
			{0x66, 0xf3, 0x73, 6}, // Q
	};

	const xImplSimd_AddSub xPADD =
		{
			{0x66, 0xdc + 0x20}, // B
			{0x66, 0xdc + 0x21}, // W
			{0x66, 0xdc + 0x22}, // D
			{0x66, 0xd4}, // Q

			{0x66, 0xdc + 0x10}, // SB
			{0x66, 0xdc + 0x11}, // SW
			{0x66, 0xdc}, // USB
			{0x66, 0xdc + 1}, // USW
	};

	const xImplSimd_AddSub xPSUB =
		{
			{0x66, 0xd8 + 0x20}, // B
			{0x66, 0xd8 + 0x21}, // W
			{0x66, 0xd8 + 0x22}, // D
			{0x66, 0xfb}, // Q

			{0x66, 0xd8 + 0x10}, // SB
			{0x66, 0xd8 + 0x11}, // SW
			{0x66, 0xd8}, // USB
			{0x66, 0xd8 + 1}, // USW
	};

	const xImplSimd_PMul xPMUL =
		{
			{0x66, 0xd5}, // LW
			{0x66, 0xe5}, // HW
			{0x66, 0xe4}, // HUW
			{0x66, 0xf4}, // UDQ

			{0x66, 0x0b38}, // HRSW
			{0x66, 0x4038}, // LD
			{0x66, 0x2838}, // DQ
	};

	const xImplSimd_rSqrt xRSQRT =
		{
			{0x00, 0x52}, // PS
			{0xf3, 0x52} // SS
	};

	const xImplSimd_rSqrt xRCP =
		{
			{0x00, 0x53}, // PS
			{0xf3, 0x53} // SS
	};

	const xImplSimd_Sqrt xSQRT =
		{
			{0x00, 0x51}, // PS
			{0xf3, 0x51}, // SS
			{0xf2, 0x51} // SS
	};

	const xImplSimd_AndNot xANDN =
		{
			{0x00, 0x55}, // PS
			{0x66, 0x55} // PD
	};

	const xImplSimd_PAbsolute xPABS =
		{
			{0x66, 0x1c38}, // B
			{0x66, 0x1d38}, // W
			{0x66, 0x1e38} // D
	};

	const xImplSimd_PSign xPSIGN =
		{
			{0x66, 0x0838}, // B
			{0x66, 0x0938}, // W
			{0x66, 0x0a38}, // D
	};

	const xImplSimd_PMultAdd xPMADD =
		{
			{0x66, 0xf5}, // WD
			{0x66, 0xf438}, // UBSW
	};

	const xImplSimd_HorizAdd xHADD =
		{
			{0xf2, 0x7c}, // PS
			{0x66, 0x7c}, // PD
	};

	const xImplSimd_DotProduct xDP =
		{
			{0x66, 0x403a}, // PS
			{0x66, 0x413a}, // PD
	};

	const xImplSimd_Round xROUND =
		{
			{0x66, 0x083a}, // PS
			{0x66, 0x093a}, // PD
			{0x66, 0x0a3a}, // SS
			{0x66, 0x0b3a}, // SD
	};

	// =====================================================================================================
	//  SIMD Comparison Instructions
	// =====================================================================================================

	void xImplSimd_Compare::PS(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(0x00, 0xc2, to, from, (u8)CType); }
	void xImplSimd_Compare::PS(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(0x00, 0xc2, to, from, (u8)CType); }

	void xImplSimd_Compare::PD(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(0x66, 0xc2, to, from, (u8)CType); }
	void xImplSimd_Compare::PD(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(0x66, 0xc2, to, from, (u8)CType); }

	void xImplSimd_Compare::SS(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(0xf3, 0xc2, to, from, (u8)CType); }
	void xImplSimd_Compare::SS(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(0xf3, 0xc2, to, from, (u8)CType); }

	void xImplSimd_Compare::SD(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(0xf2, 0xc2, to, from, (u8)CType); }
	void xImplSimd_Compare::SD(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(0xf2, 0xc2, to, from, (u8)CType); }

	const xImplSimd_MinMax xMIN =
		{
			{0x00, 0x5d}, // PS
			{0x66, 0x5d}, // PD
			{0xf3, 0x5d}, // SS
			{0xf2, 0x5d}, // SD
	};

	const xImplSimd_MinMax xMAX =
		{
			{0x00, 0x5f}, // PS
			{0x66, 0x5f}, // PD
			{0xf3, 0x5f}, // SS
			{0xf2, 0x5f}, // SD
	};

	// [TODO] : Merge this into the xCMP class, so that they are notation as: xCMP.EQ

	const xImplSimd_Compare xCMPEQ = {SSE2_Equal};
	const xImplSimd_Compare xCMPLT = {SSE2_Less};
	const xImplSimd_Compare xCMPLE = {SSE2_LessOrEqual};
	const xImplSimd_Compare xCMPUNORD = {SSE2_LessOrEqual};
	const xImplSimd_Compare xCMPNE = {SSE2_NotEqual};
	const xImplSimd_Compare xCMPNLT = {SSE2_NotLess};
	const xImplSimd_Compare xCMPNLE = {SSE2_NotLessOrEqual};
	const xImplSimd_Compare xCMPORD = {SSE2_Ordered};

	const xImplSimd_COMI xCOMI =
		{
			{0x00, 0x2f}, // SS
			{0x66, 0x2f}, // SD
	};

	const xImplSimd_COMI xUCOMI =
		{
			{0x00, 0x2e}, // SS
			{0x66, 0x2e}, // SD
	};

	const xImplSimd_PCompare xPCMP =
		{
			{0x66, 0x74}, // EQB
			{0x66, 0x75}, // EQW
			{0x66, 0x76}, // EQD

			{0x66, 0x64}, // GTB
			{0x66, 0x65}, // GTW
			{0x66, 0x66}, // GTD
	};

	const xImplSimd_PMinMax xPMIN =
		{
			{0x66, 0xda}, // UB
			{0x66, 0xea}, // SW
			{0x66, 0x3838}, // SB
			{0x66, 0x3938}, // SD

			{0x66, 0x3a38}, // UW
			{0x66, 0x3b38}, // UD
	};

	const xImplSimd_PMinMax xPMAX =
		{
			{0x66, 0xde}, // UB
			{0x66, 0xee}, // SW
			{0x66, 0x3c38}, // SB
			{0x66, 0x3d38}, // SD

			{0x66, 0x3e38}, // UW
			{0x66, 0x3f38}, // UD
	};

	// =====================================================================================================
	//  SIMD Shuffle/Pack  (Shuffle puck?)
	// =====================================================================================================

	__fi void xImplSimd_Shuffle::_selector_assertion_check(u8 selector) const
	{
		pxAssertMsg((selector & ~3) == 0,
			"Invalid immediate operand on SSE Shuffle: Upper 6 bits of the SSE Shuffle-PD Selector are reserved and must be zero.");
	}

	void xImplSimd_Shuffle::PS(const xRegisterSSE& to, const xRegisterSSE& from, u8 selector) const
	{
		xOpWrite0F(0xc6, to, from, selector);
	}

	void xImplSimd_Shuffle::PS(const xRegisterSSE& to, const xIndirectVoid& from, u8 selector) const
	{
		xOpWrite0F(0xc6, to, from, selector);
	}

	void xImplSimd_Shuffle::PD(const xRegisterSSE& to, const xRegisterSSE& from, u8 selector) const
	{
		_selector_assertion_check(selector);
		xOpWrite0F(0x66, 0xc6, to, from, selector & 0x3);
	}

	void xImplSimd_Shuffle::PD(const xRegisterSSE& to, const xIndirectVoid& from, u8 selector) const
	{
		_selector_assertion_check(selector);
		xOpWrite0F(0x66, 0xc6, to, from, selector & 0x3);
	}

	void xImplSimd_PInsert::B(const xRegisterSSE& to, const xRegister32& from, u8 imm8) const { xOpWrite0F(0x66, 0x203a, to, from, imm8); }
	void xImplSimd_PInsert::B(const xRegisterSSE& to, const xIndirect32& from, u8 imm8) const { xOpWrite0F(0x66, 0x203a, to, from, imm8); }

	void xImplSimd_PInsert::W(const xRegisterSSE& to, const xRegister32& from, u8 imm8) const { xOpWrite0F(0x66, 0xc4, to, from, imm8); }
	void xImplSimd_PInsert::W(const xRegisterSSE& to, const xIndirect32& from, u8 imm8) const { xOpWrite0F(0x66, 0xc4, to, from, imm8); }

	void xImplSimd_PInsert::D(const xRegisterSSE& to, const xRegister32& from, u8 imm8) const { xOpWrite0F(0x66, 0x223a, to, from, imm8); }
	void xImplSimd_PInsert::D(const xRegisterSSE& to, const xIndirect32& from, u8 imm8) const { xOpWrite0F(0x66, 0x223a, to, from, imm8); }

	void xImplSimd_PInsert::Q(const xRegisterSSE& to, const xRegister64& from, u8 imm8) const { xOpWrite0F(0x66, 0x223a, to, from, imm8); }
	void xImplSimd_PInsert::Q(const xRegisterSSE& to, const xIndirect64& from, u8 imm8) const { xOpWrite0F(0x66, 0x223a, to, from, imm8); }

	void SimdImpl_PExtract::B(const xRegister32& to, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x143a, from, to, imm8); }
	void SimdImpl_PExtract::B(const xIndirect32& dest, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x143a, from, dest, imm8); }

	void SimdImpl_PExtract::W(const xRegister32& to, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0xc5, from, to, imm8); }
	void SimdImpl_PExtract::W(const xIndirect32& dest, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x153a, from, dest, imm8); }

	void SimdImpl_PExtract::D(const xRegister32& to, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x163a, from, to, imm8); }
	void SimdImpl_PExtract::D(const xIndirect32& dest, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x163a, from, dest, imm8); }

	void SimdImpl_PExtract::Q(const xRegister64& to, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x163a, from, to, imm8); }
	void SimdImpl_PExtract::Q(const xIndirect64& dest, const xRegisterSSE& from, u8 imm8) const { xOpWrite0F(0x66, 0x163a, from, dest, imm8); }

	const xImplSimd_Shuffle xSHUF = {};

	const xImplSimd_PShuffle xPSHUF =
		{
			{0x66, 0x70}, // D
			{0xf2, 0x70}, // LW
			{0xf3, 0x70}, // HW

			{0x66, 0x0038}, // B
	};

	const SimdImpl_PUnpack xPUNPCK =
		{
			{0x66, 0x60}, // LBW
			{0x66, 0x61}, // LWD
			{0x66, 0x62}, // LDQ
			{0x66, 0x6c}, // LQDQ

			{0x66, 0x68}, // HBW
			{0x66, 0x69}, // HWD
			{0x66, 0x6a}, // HDQ
			{0x66, 0x6d}, // HQDQ
	};

	const SimdImpl_Pack xPACK =
		{
			{0x66, 0x63}, // SSWB
			{0x66, 0x6b}, // SSDW
			{0x66, 0x67}, // USWB
			{0x66, 0x2b38}, // USDW
	};

	const xImplSimd_Unpack xUNPCK =
		{
			{0x00, 0x15}, // HPS
			{0x66, 0x15}, // HPD
			{0x00, 0x14}, // LPS
			{0x66, 0x14}, // LPD
	};

	const xImplSimd_PInsert xPINSR;
	const SimdImpl_PExtract xPEXTR;

	// =====================================================================================================
	//  SIMD Move And Blend Instructions
	// =====================================================================================================

	void xImplSimd_MovHL::PS(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(Opcode, to, from); }
	void xImplSimd_MovHL::PS(const xIndirectVoid& to, const xRegisterSSE& from) const { xOpWrite0F(Opcode + 1, from, to); }

	void xImplSimd_MovHL::PD(const xRegisterSSE& to, const xIndirectVoid& from) const { xOpWrite0F(0x66, Opcode, to, from); }
	void xImplSimd_MovHL::PD(const xIndirectVoid& to, const xRegisterSSE& from) const { xOpWrite0F(0x66, Opcode + 1, from, to); }

	void xImplSimd_MovHL_RtoR::PS(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(Opcode, to, from); }
	void xImplSimd_MovHL_RtoR::PD(const xRegisterSSE& to, const xRegisterSSE& from) const { xOpWrite0F(0x66, Opcode, to, from); }

	static const u16 MovPS_OpAligned = 0x28; // Aligned [aps] form
	static const u16 MovPS_OpUnaligned = 0x10; // unaligned [ups] form

	void xImplSimd_MoveSSE::operator()(const xRegisterSSE& to, const xRegisterSSE& from) const
	{
		if (to != from)
			xOpWrite0F(Prefix, MovPS_OpAligned, to, from);
	}

	void xImplSimd_MoveSSE::operator()(const xRegisterSSE& to, const xIndirectVoid& from) const
	{
		// ModSib form is aligned if it's displacement-only and the displacement is aligned:
		bool isReallyAligned = isAligned || (((from.Displacement & 0x0f) == 0) && from.Index.IsEmpty() && from.Base.IsEmpty());

		xOpWrite0F(Prefix, isReallyAligned ? MovPS_OpAligned : MovPS_OpUnaligned, to, from);
	}

	void xImplSimd_MoveSSE::operator()(const xIndirectVoid& to, const xRegisterSSE& from) const
	{
		// ModSib form is aligned if it's displacement-only and the displacement is aligned:
		bool isReallyAligned = isAligned || ((to.Displacement & 0x0f) == 0 && to.Index.IsEmpty() && to.Base.IsEmpty());
		xOpWrite0F(Prefix, isReallyAligned ? MovPS_OpAligned + 1 : MovPS_OpUnaligned + 1, from, to);
	}

	static const u8 MovDQ_PrefixAligned = 0x66; // Aligned [dqa] form
	static const u8 MovDQ_PrefixUnaligned = 0xf3; // unaligned [dqu] form

	void xImplSimd_MoveDQ::operator()(const xRegisterSSE& to, const xRegisterSSE& from) const
	{
		if (to != from)
			xOpWrite0F(MovDQ_PrefixAligned, 0x6f, to, from);
	}

	void xImplSimd_MoveDQ::operator()(const xRegisterSSE& to, const xIndirectVoid& from) const
	{
		// ModSib form is aligned if it's displacement-only and the displacement is aligned:
		bool isReallyAligned = isAligned || ((from.Displacement & 0x0f) == 0 && from.Index.IsEmpty() && from.Base.IsEmpty());
		xOpWrite0F(isReallyAligned ? MovDQ_PrefixAligned : MovDQ_PrefixUnaligned, 0x6f, to, from);
	}

	void xImplSimd_MoveDQ::operator()(const xIndirectVoid& to, const xRegisterSSE& from) const
	{
		// ModSib form is aligned if it's displacement-only and the displacement is aligned:
		bool isReallyAligned = isAligned || ((to.Displacement & 0x0f) == 0 && to.Index.IsEmpty() && to.Base.IsEmpty());

		// use opcode 0x7f : alternate ModRM encoding (reverse src/dst)
		xOpWrite0F(isReallyAligned ? MovDQ_PrefixAligned : MovDQ_PrefixUnaligned, 0x7f, from, to);
	}

	void xImplSimd_PMove::BW(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase); }
	void xImplSimd_PMove::BW(const xRegisterSSE& to, const xIndirect64& from) const { OpWriteSSE(0x66, OpcodeBase); }

	void xImplSimd_PMove::BD(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase + 0x100); }
	void xImplSimd_PMove::BD(const xRegisterSSE& to, const xIndirect32& from) const { OpWriteSSE(0x66, OpcodeBase + 0x100); }

	void xImplSimd_PMove::BQ(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase + 0x200); }
	void xImplSimd_PMove::BQ(const xRegisterSSE& to, const xIndirect16& from) const { OpWriteSSE(0x66, OpcodeBase + 0x200); }

	void xImplSimd_PMove::WD(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase + 0x300); }
	void xImplSimd_PMove::WD(const xRegisterSSE& to, const xIndirect64& from) const { OpWriteSSE(0x66, OpcodeBase + 0x300); }

	void xImplSimd_PMove::WQ(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase + 0x400); }
	void xImplSimd_PMove::WQ(const xRegisterSSE& to, const xIndirect32& from) const { OpWriteSSE(0x66, OpcodeBase + 0x400); }

	void xImplSimd_PMove::DQ(const xRegisterSSE& to, const xRegisterSSE& from) const { OpWriteSSE(0x66, OpcodeBase + 0x500); }
	void xImplSimd_PMove::DQ(const xRegisterSSE& to, const xIndirect64& from) const { OpWriteSSE(0x66, OpcodeBase + 0x500); }


	const xImplSimd_MoveSSE xMOVAPS = {0x00, true};
	const xImplSimd_MoveSSE xMOVUPS = {0x00, false};

#ifdef ALWAYS_USE_MOVAPS
	const xImplSimd_MoveSSE xMOVDQA = {0x00, true};
	const xImplSimd_MoveSSE xMOVAPD = {0x00, true};

	const xImplSimd_MoveSSE xMOVDQU = {0x00, false};
	const xImplSimd_MoveSSE xMOVUPD = {0x00, false};
#else
	const xImplSimd_MoveDQ xMOVDQA = {0x66, true};
	const xImplSimd_MoveSSE xMOVAPD = {0x66, true};

	const xImplSimd_MoveDQ xMOVDQU = {0xf3, false};
	const xImplSimd_MoveSSE xMOVUPD = {0x66, false};
#endif


	const xImplSimd_MovHL xMOVH = {0x16};
	const xImplSimd_MovHL xMOVL = {0x12};

	const xImplSimd_MovHL_RtoR xMOVLH = {0x16};
	const xImplSimd_MovHL_RtoR xMOVHL = {0x12};

	const xImplSimd_Blend xBLEND =
		{
			{0x66, 0x0c3a}, // PS
			{0x66, 0x0d3a}, // PD
			{0x66, 0x1438}, // VPS
			{0x66, 0x1538}, // VPD
	};

	const xImplSimd_PMove xPMOVSX = {0x2038};
	const xImplSimd_PMove xPMOVZX = {0x3038};

	// [SSE-3]
	const xImplSimd_DestRegSSE xMOVSLDUP = {0xf3, 0x12};

	// [SSE-3]
	const xImplSimd_DestRegSSE xMOVSHDUP = {0xf3, 0x16};

	//////////////////////////////////////////////////////////////////////////////////////////
	// MMX Mov Instructions (MOVD, MOVQ, MOVSS).
	//
	// Notes:
	//  * Some of the functions have been renamed to more clearly reflect what they actually
	//    do.  Namely we've affixed "ZX" to several MOVs that take a register as a destination
	//    since that's what they do (MOVD clears upper 32/96 bits, etc).
	//
	//  * MOVD has valid forms for MMX and XMM registers.
	//

	__fi void xMOVDZX(const xRegisterSSE& to, const xRegister32or64& from) { xOpWrite0F(0x66, 0x6e, to, from); }
	__fi void xMOVDZX(const xRegisterSSE& to, const xIndirectVoid& src) { xOpWrite0F(0x66, 0x6e, to, src); }

	__fi void xMOVD(const xRegister32or64& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0x7e, from, to); }
	__fi void xMOVD(const xIndirectVoid& dest, const xRegisterSSE& from) { xOpWrite0F(0x66, 0x7e, from, dest); }

	// Moves from XMM to XMM, with the *upper 64 bits* of the destination register
	// being cleared to zero.
	__fi void xMOVQZX(const xRegisterSSE& to, const xRegisterSSE& from) { xOpWrite0F(0xf3, 0x7e, to, from); }

	// Moves from XMM to XMM, with the *upper 64 bits* of the destination register
	// being cleared to zero.
	__fi void xMOVQZX(const xRegisterSSE& to, const xIndirectVoid& src) { xOpWrite0F(0xf3, 0x7e, to, src); }

	// Moves from XMM to XMM, with the *upper 64 bits* of the destination register
	// being cleared to zero.
	__fi void xMOVQZX(const xRegisterSSE& to, const void* src) { xOpWrite0F(0xf3, 0x7e, to, src); }

	// Moves lower quad of XMM to ptr64 (no bits are cleared)
	__fi void xMOVQ(const xIndirectVoid& dest, const xRegisterSSE& from) { xOpWrite0F(0x66, 0xd6, from, dest); }

	//////////////////////////////////////////////////////////////////////////////////////////
	//

#define IMPLEMENT_xMOVS(ssd, prefix) \
	__fi void xMOV##ssd(const xRegisterSSE& to, const xRegisterSSE& from) \
	{ \
		if (to != from) \
			xOpWrite0F(prefix, 0x10, to, from); \
	} \
	__fi void xMOV##ssd##ZX(const xRegisterSSE& to, const xIndirectVoid& from) { xOpWrite0F(prefix, 0x10, to, from); } \
	__fi void xMOV##ssd(const xIndirectVoid& to, const xRegisterSSE& from) { xOpWrite0F(prefix, 0x11, from, to); }

	IMPLEMENT_xMOVS(SS, 0xf3)
		IMPLEMENT_xMOVS(SD, 0xf2)

		//////////////////////////////////////////////////////////////////////////////////////////
		// Non-temporal movs only support a register as a target (ie, load form only, no stores)
		//

		__fi void xMOVNTDQA(const xRegisterSSE& to, const xIndirectVoid& from)
	{
		xOpWrite0F(0x66, 0x2a38, to.Id, from);
	}

	__fi void xMOVNTDQA(const xIndirectVoid& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0xe7, from, to); }

	__fi void xMOVNTPD(const xIndirectVoid& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0x2b, from, to); }
	__fi void xMOVNTPS(const xIndirectVoid& to, const xRegisterSSE& from) { xOpWrite0F(0x2b, from, to); }

	// ------------------------------------------------------------------------

	__fi void xMOVMSKPS(const xRegister32& to, const xRegisterSSE& from) { xOpWrite0F(0x50, to, from); }
	__fi void xMOVMSKPD(const xRegister32& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0x50, to, from, true); }

	// xMASKMOV:
	// Selectively write bytes from mm1/xmm1 to memory location using the byte mask in mm2/xmm2.
	// The default memory location is specified by DS:EDI.  The most significant bit in each byte
	// of the mask operand determines whether the corresponding byte in the source operand is
	// written to the corresponding byte location in memory.
	__fi void xMASKMOV(const xRegisterSSE& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0xf7, to, from); }

	// xPMOVMSKB:
	// Creates a mask made up of the most significant bit of each byte of the source
	// operand and stores the result in the low byte or word of the destination operand.
	// Upper bits of the destination are cleared to zero.
	//
	// When operating on a 64-bit (MMX) source, the byte mask is 8 bits; when operating on
	// 128-bit (SSE) source, the byte mask is 16-bits.
	//
	__fi void xPMOVMSKB(const xRegister32or64& to, const xRegisterSSE& from) { xOpWrite0F(0x66, 0xd7, to, from); }

	// [sSSE-3] Concatenates dest and source operands into an intermediate composite,
	// shifts the composite at byte granularity to the right by a constant immediate,
	// and extracts the right-aligned result into the destination.
	//
	__fi void xPALIGNR(const xRegisterSSE& to, const xRegisterSSE& from, u8 imm8) { xOpWrite0F(0x66, 0x0f3a, to, from, imm8); }


	// --------------------------------------------------------------------------------------
	//  INSERTPS / EXTRACTPS   [SSE4.1 only!]
	// --------------------------------------------------------------------------------------
	// [TODO] these might be served better as classes, especially if other instructions use
	// the M32,sse,imm form (I forget offhand if any do).


	// [SSE-4.1] Insert a single-precision floating-point value from src into a specified
	// location in dest, and selectively zero out the data elements in dest according to
	// the mask  field in the immediate byte. The source operand can be a memory location
	// (32 bits) or an XMM register (lower 32 bits used).
	//
	// Imm8 provides three fields:
	//  * COUNT_S: The value of Imm8[7:6] selects the dword element from src.  It is 0 if
	//    the source is a memory operand.
	//  * COUNT_D: The value of Imm8[5:4] selects the target dword element in dest.
	//  * ZMASK: Each bit of Imm8[3:0] selects a dword element in dest to  be written
	//    with 0.0 if set to 1.
	//
	__emitinline void xINSERTPS(const xRegisterSSE& to, const xRegisterSSE& from, u8 imm8) { xOpWrite0F(0x66, 0x213a, to, from, imm8); }
	__emitinline void xINSERTPS(const xRegisterSSE& to, const xIndirect32& from, u8 imm8) { xOpWrite0F(0x66, 0x213a, to, from, imm8); }

	// [SSE-4.1] Extract a single-precision floating-point value from src at an offset
	// determined by imm8[1-0]*32. The extracted single precision floating-point value
	// is stored into the low 32-bits of dest (or at a 32-bit memory pointer).
	//
	__emitinline void xEXTRACTPS(const xRegister32or64& to, const xRegisterSSE& from, u8 imm8) { xOpWrite0F(0x66, 0x173a, to, from, imm8); }
	__emitinline void xEXTRACTPS(const xIndirect32& dest, const xRegisterSSE& from, u8 imm8) { xOpWrite0F(0x66, 0x173a, from, dest, imm8); }


	// =====================================================================================================
	//  Ungrouped Instructions!
	// =====================================================================================================


	// Store Streaming SIMD Extension Control/Status to Mem32.
	__emitinline void xSTMXCSR(const xIndirect32& dest)
	{
		xOpWrite0F(0, 0xae, 3, dest);
	}

	// Load Streaming SIMD Extension Control/Status from Mem32.
	__emitinline void xLDMXCSR(const xIndirect32& src)
	{
		xOpWrite0F(0, 0xae, 2, src);
	}

	// Save x87 FPU, MMX Technology, and SSE State to buffer
	// Target buffer must be at least 512 bytes in length to hold the result.
	__emitinline void xFXSAVE(const xIndirectVoid& dest)
	{
		xOpWrite0F(0, 0xae, 0, dest);
	}

	// Restore x87 FPU, MMX , XMM, and MXCSR State.
	// Source buffer should be 512 bytes in length.
	__emitinline void xFXRSTOR(const xIndirectVoid& src)
	{
		xOpWrite0F(0, 0xae, 1, src);
	}
} // namespace x86Emitter