| // Copyright 2016 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. |
| |
| #include "textflag.h" |
| |
| TEXT runtime∕internal∕sys·TrailingZeros64(SB), NOSPLIT, $0-12 |
| // Try low 32 bits. |
| MOVL x_lo+0(FP), AX |
| BSFL AX, AX |
| JZ tryhigh |
| MOVL AX, ret+8(FP) |
| RET |
| |
| tryhigh: |
| // Try high 32 bits. |
| MOVL x_hi+4(FP), AX |
| BSFL AX, AX |
| JZ none |
| ADDL $32, AX |
| MOVL AX, ret+8(FP) |
| RET |
| |
| none: |
| // No bits are set. |
| MOVL $64, ret+8(FP) |
| RET |
| |
| TEXT runtime∕internal∕sys·TrailingZeros32(SB), NOSPLIT, $0-8 |
| MOVL x+0(FP), AX |
| BSFL AX, AX |
| JNZ 2(PC) |
| MOVL $32, AX |
| MOVL AX, ret+4(FP) |
| RET |
| |
| TEXT runtime∕internal∕sys·TrailingZeros8(SB), NOSPLIT, $0-8 |
| MOVBLZX x+0(FP), AX |
| BSFL AX, AX |
| JNZ 2(PC) |
| MOVL $8, AX |
| MOVL AX, ret+4(FP) |
| RET |
