}

func messWith(fileName string, corrupter func(b []byte)) (r io.ReaderAt, size int64) {
	data, err := os.ReadFile(filepath.Join("testdata", fileName))
	if err != nil {
		panic("Error reading " + fileName + ": " + err.Error())
	}
	corrupter(data)
	return bytes.NewReader(data), int64(len(data))
}

func returnCorruptCRC32Zip() (r io.ReaderAt, size int64) {
	return messWith("go-with-datadesc-sig.zip", func(b []byte) {

	w.buf = append(w.buf, p...)
	w.writeBytes += len(p)
	return len(p), nil
}

func (w *readFromWriter) ReadFrom(r io.Reader) (int64, error) {
	b, err := io.ReadAll(r)
	w.buf = append(w.buf, b...)
	w.readFromBytes += len(b)
	return int64(len(b)), err
}

// Test that calling (*Writer).ReadFrom with a partially-filled buffer
// fills the buffer before switching over to ReadFrom.

func (c *typeConv) pad(fld []*ast.Field, sizes []int64, size int64) ([]*ast.Field, []int64) {
	n := len(fld)
	fld = fld[0 : n+1]
	fld[n] = &ast.Field{Names: []*ast.Ident{c.Ident("_")}, Type: c.Opaque(size)}
	sizes = sizes[0 : n+1]
	sizes[n] = size
	return fld, sizes
}

// Struct conversion: return Go and (gc) C syntax for type.

	for _, n := range sizes {
		if isRaceBuilder && n > 4<<10 {
			continue
		}
		b.Run(valName(n), func(b *testing.B) {
			if len(bmbuf) < n {
				bmbuf = make([]byte, n)
			}
			b.SetBytes(int64(n))
			f(b, n)
		})
	}
}

var indexSizes = []int{10, 32, 4 << 10, 4 << 20, 64 << 20}

var isRaceBuilder = strings.HasSuffix(testenv.Builder(), "-race")

func BenchmarkIndexByte(b *testing.B) {

//		g.Type = obj.TYPE_CONST;
//		g.Offset = int64($6);
//		outcode($1, $2, &$3, 0, &g);
//	}
	MOVM	0(R1), [R2,R5,R8,g] // MOVM	(R1), [R2,R5,R8,g]
	MOVM	(R1), [R2-R5] // MOVM (R1), [R2,R3,R4,R5]
	MOVM	(R1), [R2]

//	LTYPE8 cond '[' reglist ']' ',' ioreg
//	{
//		var g obj.Addr
//
//		g = nullgen;
//		g.Type = obj.TYPE_CONST;
//		g.Offset = int64($4);
//		outcode($1, $2, &g, 0, &$7);
//	}