VMOVHPD 7(DX), X5, X5            // c5d1166a07 or 62f1d52816aa07000000 or 62f1d54816aa07000000
	VMOVHPD -15(R11)(CX*1), X5, X5   // c4c151166c0bf1 or 62d1d52816ac0bf1ffffff or 62d1d54816ac0bf1ffffff
	VMOVHPD (SP)(AX*2), X5, X5       // c5d1162c44 or c4e1d1162c44 or 62f1d528162c44 or 62f1d548162c44
	VMOVHPD (AX), X8, X5             // c5b91628 or c4e1b91628 or 62f1bd281628 or 62f1bd481628

	// which names a file in the testdata/ directory containing the
	// uncompressed expected content.
	// If content is very large, an alternative to setting Content or File
	// is to set Size, which will then be checked against the header-reported size
	// but will bypass the decompressing of the actual data.
	// This last option is used for testing very large (multi-GB) compressed files.

	r := NewReader(strings.NewReader("line 1\n"))
	for i := 0; i < 2; i++ {
		l, _, err := r.ReadLine()
		if l != nil && err != nil {
			t.Fatalf("on line %d/2; ReadLine=%#v, %v; want non-nil line or Error, but not both",
				i+1, l, err)
		}
	}
}

type readLineResult struct {
	line     []byte
	isPrefix bool
	err      error
}

var readLineNewlinesTests = []struct {

	}

	// Coerce gcc into telling us whether each name is a type, a value, or undeclared.
	// For names, find out whether they are integer constants.
	// We used to look at specific warning or error messages here, but that tied the
	// behavior too closely to specific versions of the compilers.
	// Instead, arrange that we can infer what we need from only the presence or absence
	// of an error on a specific line.
	//

	FMOVD	1(R1), F2 // 221040fc
	FMOVD	8(R1), F2 // 220440fd
	FMOVQ	32(R5), F2 // a208c03d
	FMOVQ	65520(R10), F10 // 4afdff3d
	FMOVQ	64(RSP), F11    // eb13c03d

// medium offsets that either fit a single instruction or can use add+ldr/str
	MOVD -4095(R17), R3                        // 3bfe3fd1630340f9
	MOVD -391(R17), R3                         // 3b1e06d1630340f9
	MOVD -257(R17), R3                         // 3b0604d1630340f9

	ANDCC $65536000, R3, R4         // 746403e8

	OR $1, R3                       // 60630001
	OR $1, R3, R4                   // 60640001
	OR $-1, R4                      // 3be0ffff7fe42378
	OR $-1, R4, R5                  // 3be0ffff7fe52378
	OR $65535, R5                   // 60a5ffff
	OR $65535, R5, R6               // 60a6ffff
	OR $65536, R6                   // 64c60001
	OR $65536, R6, R7               // 64c70001