for i := range b {
			idx := Index(b[i:], q[:j])
			if idx != -1 {
				t.Fatalf("Index(b[%d:], q[:%d])=%d, want -1\n", i, j, idx)
			}
		}
		q[j-1] = 0
	}

	// Test differing alignments and sizes of q which always end on a page boundary.
	q[len(q)-1] = 1 // difference is only found on the last byte
	for j := 0; j < len(q); j++ {
		for i := range b {
			idx := Index(b[i:], q[j:])
			if idx != -1 {

	n, perr := strconv.ParseInt(nStr, 10, 0) // Intentionally parse as native int
	if perr != nil || n < 5 || n > int64(len(s)) {
		return "", "", s, ErrHeader
	}
	n -= int64(len(nStr) + 1) // convert from index in s to index in rest
	if n <= 0 {
		return "", "", s, ErrHeader
	}

	// Extract everything between the space and the final newline.
	rec, nl, rem := rest[:n-1], rest[n-1:n], rest[n:]
	if nl != "\n" {

	// Intel pseudonyms for our own renamings.
	PADDD	M2, M1 // PADDL M2, M1
	MOVDQ2Q	X1, M1 // MOVQ X1, M1
	MOVNTDQ	X1, (AX)	// MOVNTO X1, (AX)
	MOVOA	(AX), X1	// MOVO (AX), X1

// Tests for SP indexed addresses.
	MOVQ	foo(SP)(AX*1), BX		// 488b1c04
	MOVQ	foo+32(SP)(CX*2), DX		// 488b544c20
	MOVQ	foo+32323(SP)(R8*4), R9		// 4e8b8c84437e0000
	MOVL	foo(SP)(SI*8), DI		// 8b3cf4
	MOVL	foo+32(SP)(R10*1), R11		// 468b5c1420

		"\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)",