M3:   "%mm3",
	M4:   "%mm4",
	M5:   "%mm5",
	M6:   "%mm6",
	M7:   "%mm7",
	X0:   "%xmm0",
	X1:   "%xmm1",
	X2:   "%xmm2",
	X3:   "%xmm3",
	X4:   "%xmm4",
	X5:   "%xmm5",
	X6:   "%xmm6",
	X7:   "%xmm7",
	X8:   "%xmm8",
	X9:   "%xmm9",
	X10:  "%xmm10",
	X11:  "%xmm11",
	X12:  "%xmm12",
	X13:  "%xmm13",
	X14:  "%xmm14",
	X15:  "%xmm15",
	CS:   "%cs",
	SS:   "%ss",

	// "VMOVQ r/m64, xmm1"/6E vs "VMOVQ xmm2/m64, xmm1"/7E with mem operand.
	VMOVQ (AX), X20           // 62e1fd086e20 or 62e1fe087e20
	VMOVQ 7(DX), X20          // 62e1fd086ea207000000 or 62e1fe087ea207000000
	VMOVQ -15(R11)(CX*1), X20 // 62c1fd086ea40bf1ffffff or 62c1fe087ea40bf1ffffff
	VMOVQ (SP)(AX*2), X20     // 62e1fd086e2444 or 62e1fe087e2444
	// "VMOVQ xmm1, r/m64"/7E vs "VMOVQ xmm1, xmm2/m64"/D6 with mem operand.

	xArgXmm          // arg xmm
	xArgXMM0         // arg <XMM0>
	xArgXmm1         // arg xmm1
	xArgXmm2         // arg xmm2
	xArgXmm2M128     // arg xmm2/m128
	xArgYmm2M256     // arg ymm2/m256
	xArgXmm2M16      // arg xmm2/m16
	xArgXmm2M32      // arg xmm2/m32
	xArgXmm2M64      // arg xmm2/m64
	xArgXmmM128      // arg xmm/m128
	xArgXmmM32       // arg xmm/m32
	xArgXmmM64       // arg xmm/m64

			c.checkindex(p, index, 15)
			Q = 1
			imm5 = 1
			imm5 |= index << 1
		case ARNG_2D:
			c.checkindex(p, index, 1)
			Q = 1
			imm5 = 8
			imm5 |= index << 4
		case ARNG_2S:
			c.checkindex(p, index, 3)
			Q = 0
			imm5 = 4
			imm5 |= index << 3
		case ARNG_4H:
			c.checkindex(p, index, 7)
			Q = 0
			imm5 = 2
			imm5 |= index << 2
		case ARNG_4S:

		"\n.\n.MOVBLZX.(.8.*.4.).(.R12.).,.AX.\n.ADDB.AX.,.DX.\n",
	},
	{
		"nested multiline macro",
		lines(
			"#define KEYROUND(xmm, load, off, r1, r2, index) \\",
			"\tMOVBLZX	(BP)(DX*4),	R8 \\",
			"\tload((off+1), r2) \\",
			"\tMOVB	R8,		(off*4)(R12) \\",
			"\tPINSRW	$index, (BP)(R8*4), xmm",
			"#define LOAD(off, reg) \\",
			"\tMOVBLZX	(off*4)(R12),	reg \\",
			"\tADDB	reg,		DX",
			"KEYROUND(X0, LOAD, 8, AX, BX, 0)",

	X86.HasRDRAND = isSet(30, ecx1)

	var osSupportsAVX, osSupportsAVX512 bool
	// For XGETBV, OSXSAVE bit is required and sufficient.
	if X86.HasOSXSAVE {
		eax, _ := xgetbv()
		// Check if XMM and YMM registers have OS support.
		osSupportsAVX = isSet(1, eax) && isSet(2, eax)

		if runtime.GOOS == "darwin" {
			// Darwin doesn't save/restore AVX-512 mask registers correctly across signal handlers.

	osSupportsAVX := false
	osSupportsAVX512 := false
	// For XGETBV, OSXSAVE bit is required and sufficient.
	if X86.HasOSXSAVE {
		eax, _ := xgetbv()
		// Check if XMM and YMM registers have OS support.
		osSupportsAVX = isSet(eax, 1<<1) && isSet(eax, 1<<2)

		// AVX512 detection does not work on Darwin,
		// see https://github.com/golang/go/issues/49233
		//

	SEED(1, SI, X5)
	SEED(2, R8, X6)
	SEED(3, R9, X7)
	SEED(4, R10, X8)
	SEED(5, R11, X9)
	SEED(6, R12, X10)
	SEED(7, R13, X11)

	// Zeros for remaining two matrix entries.
	// We have just enough XMM registers to hold the state,
	// without one for the temporary, so we flush and restore
	// some values to and from memory to provide a temporary.
	// The initial temporary is X15, so zero its memory instead
	// of X15 itself.

_0args:

	// Call stdcall function.
	CALL	AX

	ADDQ	$(const_maxArgs*8), SP

	// Return result.
	MOVQ	0(SP), CX
	MOVQ	8(SP), SP
	MOVQ	AX, libcall_r1(CX)
	// Floating point return values are returned in XMM0. Setting r2 to this
	// value in case this call returned a floating point value. For details,
	// see https://docs.microsoft.com/en-us/cpp/build/x64-calling-convention
	MOVQ    X0, libcall_r2(CX)

	// GetLastError().

	// 387 floating point registers.
	F0
	F1
	F2
	F3
	F4
	F5
	F6
	F7

	// MMX registers.
	M0
	M1
	M2
	M3
	M4
	M5
	M6
	M7

	// XMM registers.
	X0
	X1
	X2
	X3
	X4
	X5
	X6
	X7
	X8
	X9
	X10
	X11
	X12
	X13
	X14
	X15

	// Segment registers.
	ES
	CS
	SS
	DS
	FS