| /* |
| * Copyright (C) 2008 The Android Open Source Project |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * * Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * * Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS |
| * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED |
| * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| */ |
| |
| #include <machine/cpu-features.h> |
| #include <machine/asm.h> |
| |
| /* |
| * Optimized memset() for ARM. |
| * |
| * memset() returns its first argument. |
| */ |
| |
| .fpu neon |
| |
| ENTRY(bzero) |
| mov r2, r1 |
| mov r1, #0 |
| // Fall through to memset... |
| END(bzero) |
| |
| ENTRY(memset) |
| .save {r0} |
| stmfd sp!, {r0} |
| |
| vdup.8 q0, r1 |
| |
| /* do we have at least 16-bytes to write (needed for alignment below) */ |
| cmp r2, #16 |
| blo 3f |
| |
| /* align destination to 16 bytes for the write-buffer */ |
| rsb r3, r0, #0 |
| ands r3, r3, #0xF |
| beq 2f |
| |
| /* write up to 15-bytes (count in r3) */ |
| sub r2, r2, r3 |
| movs ip, r3, lsl #31 |
| strmib r1, [r0], #1 |
| strcsb r1, [r0], #1 |
| strcsb r1, [r0], #1 |
| movs ip, r3, lsl #29 |
| bge 1f |
| |
| // writes 4 bytes, 32-bits aligned |
| vst1.32 {d0[0]}, [r0, :32]! |
| 1: bcc 2f |
| |
| // writes 8 bytes, 64-bits aligned |
| vst1.8 {d0}, [r0, :64]! |
| 2: |
| /* make sure we have at least 32 bytes to write */ |
| subs r2, r2, #32 |
| blo 2f |
| vmov q1, q0 |
| |
| 1: /* The main loop writes 32 bytes at a time */ |
| subs r2, r2, #32 |
| vst1.8 {d0 - d3}, [r0, :128]! |
| bhs 1b |
| |
| 2: /* less than 32 left */ |
| add r2, r2, #32 |
| tst r2, #0x10 |
| beq 3f |
| |
| // writes 16 bytes, 128-bits aligned |
| vst1.8 {d0, d1}, [r0, :128]! |
| 3: /* write up to 15-bytes (count in r2) */ |
| movs ip, r2, lsl #29 |
| bcc 1f |
| vst1.8 {d0}, [r0]! |
| 1: bge 2f |
| vst1.32 {d0[0]}, [r0]! |
| 2: movs ip, r2, lsl #31 |
| strmib r1, [r0], #1 |
| strcsb r1, [r0], #1 |
| strcsb r1, [r0], #1 |
| ldmfd sp!, {r0} |
| bx lr |
| END(memset) |
