| // Copyright 2009 The Go Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style |
| // license that can be found in the LICENSE file. |
| |
| // This file provides fast assembly versions |
| // of the routines in arith.go. |
| |
| // func Mul128(x, y uint64) (z1, z0 uint64) |
| // z1<<64 + z0 = x*y |
| // |
| TEXT ·Mul128(SB),7,$0 |
| MOVQ a+0(FP), AX |
| MULQ a+8(FP) |
| MOVQ DX, a+16(FP) |
| MOVQ AX, a+24(FP) |
| RET |
| |
| |
| // func MulAdd128(x, y, c uint64) (z1, z0 uint64) |
| // z1<<64 + z0 = x*y + c |
| // |
| TEXT ·MulAdd128(SB),7,$0 |
| MOVQ a+0(FP), AX |
| MULQ a+8(FP) |
| ADDQ a+16(FP), AX |
| ADCQ $0, DX |
| MOVQ DX, a+24(FP) |
| MOVQ AX, a+32(FP) |
| RET |
| |
| |
| // func Div128(x1, x0, y uint64) (q, r uint64) |
| // q = (x1<<64 + x0)/y + r |
| // |
| TEXT ·Div128(SB),7,$0 |
| MOVQ a+0(FP), DX |
| MOVQ a+8(FP), AX |
| DIVQ a+16(FP) |
| MOVQ AX, a+24(FP) |
| MOVQ DX, a+32(FP) |
| RET |
