diff options
Diffstat (limited to 'libc/arch-arm/cortex-a15/bionic/strcpy.S')
| -rw-r--r-- | libc/arch-arm/cortex-a15/bionic/strcpy.S | 427 |
1 files changed, 3 insertions, 424 deletions
diff --git a/libc/arch-arm/cortex-a15/bionic/strcpy.S b/libc/arch-arm/cortex-a15/bionic/strcpy.S index cb878c4..951face 100644 --- a/libc/arch-arm/cortex-a15/bionic/strcpy.S +++ b/libc/arch-arm/cortex-a15/bionic/strcpy.S @@ -1,5 +1,5 @@ /* - * Copyright (C) 2013 The Android Open Source Project + * Copyright (C) 2014 The Android Open Source Project * All rights reserved. * * Redistribution and use in source and binary forms, with or without @@ -25,427 +25,6 @@ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ -/* - * Copyright (c) 2013 ARM Ltd - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * 2. 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. - * 3. The name of the company may not be used to endorse or promote - * products derived from this software without specific prior written - * permission. - * - * THIS SOFTWARE IS PROVIDED BY ARM LTD ``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 ARM LTD 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 <private/bionic_asm.h> - - .syntax unified - - .thumb - .thumb_func - - .macro m_push - push {r0, r4, r5, lr} - .endm // m_push - - .macro m_pop - pop {r0, r4, r5, pc} - .endm // m_pop - - .macro m_copy_byte reg, cmd, label - ldrb \reg, [r1], #1 - strb \reg, [r0], #1 - \cmd \reg, \label - .endm // m_copy_byte - -ENTRY(strcpy) - // For short copies, hard-code checking the first 8 bytes since this - // new code doesn't win until after about 8 bytes. - m_push - m_copy_byte reg=r2, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r3, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r4, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r5, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r2, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r3, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r4, cmd=cbz, label=strcpy_finish - m_copy_byte reg=r5, cmd=cbnz, label=strcpy_continue - -strcpy_finish: - m_pop - -strcpy_continue: - pld [r1, #0] - ands r3, r0, #7 - beq strcpy_check_src_align - - // Align to a double word (64 bits). - rsb r3, r3, #8 - lsls ip, r3, #31 - beq strcpy_align_to_32 - - ldrb r2, [r1], #1 - strb r2, [r0], #1 - cbz r2, strcpy_complete - -strcpy_align_to_32: - bcc strcpy_align_to_64 - - ldrb r2, [r1], #1 - strb r2, [r0], #1 - cbz r2, strcpy_complete - ldrb r2, [r1], #1 - strb r2, [r0], #1 - cbz r2, strcpy_complete - -strcpy_align_to_64: - tst r3, #4 - beq strcpy_check_src_align - ldr r2, [r1], #4 - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - str r2, [r0], #4 - -strcpy_check_src_align: - // At this point dst is aligned to a double word, check if src - // is also aligned to a double word. - ands r3, r1, #7 - bne strcpy_unaligned_copy - - .p2align 2 -strcpy_mainloop: - ldrd r2, r3, [r1], #8 - - pld [r1, #64] - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_mainloop - -strcpy_complete: - m_pop - -strcpy_zero_in_first_register: - lsls lr, ip, #17 - bne strcpy_copy1byte - bcs strcpy_copy2bytes - lsls ip, ip, #1 - bne strcpy_copy3bytes - -strcpy_copy4bytes: - // Copy 4 bytes to the destiniation. - str r2, [r0] - m_pop - -strcpy_copy1byte: - strb r2, [r0] - m_pop - -strcpy_copy2bytes: - strh r2, [r0] - m_pop - -strcpy_copy3bytes: - strh r2, [r0], #2 - lsr r2, #16 - strb r2, [r0] - m_pop - -strcpy_zero_in_second_register: - lsls lr, ip, #17 - bne strcpy_copy5bytes - bcs strcpy_copy6bytes - lsls ip, ip, #1 - bne strcpy_copy7bytes - - // Copy 8 bytes to the destination. - strd r2, r3, [r0] - m_pop - -strcpy_copy5bytes: - str r2, [r0], #4 - strb r3, [r0] - m_pop - -strcpy_copy6bytes: - str r2, [r0], #4 - strh r3, [r0] - m_pop - -strcpy_copy7bytes: - str r2, [r0], #4 - strh r3, [r0], #2 - lsr r3, #16 - strb r3, [r0] - m_pop - -strcpy_unaligned_copy: - // Dst is aligned to a double word, while src is at an unknown alignment. - // There are 7 different versions of the unaligned copy code - // to prevent overreading the src. The mainloop of every single version - // will store 64 bits per loop. The difference is how much of src can - // be read without potentially crossing a page boundary. - tbb [pc, r3] -strcpy_unaligned_branchtable: - .byte 0 - .byte ((strcpy_unalign7 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign6 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign5 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign4 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign3 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign2 - strcpy_unaligned_branchtable)/2) - .byte ((strcpy_unalign1 - strcpy_unaligned_branchtable)/2) - - .p2align 2 - // Can read 7 bytes before possibly crossing a page. -strcpy_unalign7: - ldr r2, [r1], #4 - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - ldrb r3, [r1] - cbz r3, strcpy_unalign7_copy5bytes - ldrb r4, [r1, #1] - cbz r4, strcpy_unalign7_copy6bytes - ldrb r5, [r1, #2] - cbz r5, strcpy_unalign7_copy7bytes - - ldr r3, [r1], #4 - pld [r1, #64] - - lsrs ip, r3, #24 - strd r2, r3, [r0], #8 - beq strcpy_unalign_return - b strcpy_unalign7 - -strcpy_unalign7_copy5bytes: - str r2, [r0], #4 - strb r3, [r0] -strcpy_unalign_return: - m_pop - -strcpy_unalign7_copy6bytes: - str r2, [r0], #4 - strb r3, [r0], #1 - strb r4, [r0], #1 - m_pop - -strcpy_unalign7_copy7bytes: - str r2, [r0], #4 - strb r3, [r0], #1 - strb r4, [r0], #1 - strb r5, [r0], #1 - m_pop - - .p2align 2 - // Can read 6 bytes before possibly crossing a page. -strcpy_unalign6: - ldr r2, [r1], #4 - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - ldrb r4, [r1] - cbz r4, strcpy_unalign_copy5bytes - ldrb r5, [r1, #1] - cbz r5, strcpy_unalign_copy6bytes - - ldr r3, [r1], #4 - pld [r1, #64] - - tst r3, #0xff0000 - beq strcpy_copy7bytes - lsrs ip, r3, #24 - strd r2, r3, [r0], #8 - beq strcpy_unalign_return - b strcpy_unalign6 - - .p2align 2 - // Can read 5 bytes before possibly crossing a page. -strcpy_unalign5: - ldr r2, [r1], #4 - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - ldrb r4, [r1] - cbz r4, strcpy_unalign_copy5bytes - - ldr r3, [r1], #4 - - pld [r1, #64] - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_unalign5 - -strcpy_unalign_copy5bytes: - str r2, [r0], #4 - strb r4, [r0] - m_pop - -strcpy_unalign_copy6bytes: - str r2, [r0], #4 - strb r4, [r0], #1 - strb r5, [r0] - m_pop - - .p2align 2 - // Can read 4 bytes before possibly crossing a page. -strcpy_unalign4: - ldr r2, [r1], #4 - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - ldr r3, [r1], #4 - pld [r1, #64] - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_unalign4 - - .p2align 2 - // Can read 3 bytes before possibly crossing a page. -strcpy_unalign3: - ldrb r2, [r1] - cbz r2, strcpy_unalign3_copy1byte - ldrb r3, [r1, #1] - cbz r3, strcpy_unalign3_copy2bytes - ldrb r4, [r1, #2] - cbz r4, strcpy_unalign3_copy3bytes - - ldr r2, [r1], #4 - ldr r3, [r1], #4 - - pld [r1, #64] - - lsrs lr, r2, #24 - beq strcpy_copy4bytes - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_unalign3 - -strcpy_unalign3_copy1byte: - strb r2, [r0] - m_pop - -strcpy_unalign3_copy2bytes: - strb r2, [r0], #1 - strb r3, [r0] - m_pop - -strcpy_unalign3_copy3bytes: - strb r2, [r0], #1 - strb r3, [r0], #1 - strb r4, [r0] - m_pop - - .p2align 2 - // Can read 2 bytes before possibly crossing a page. -strcpy_unalign2: - ldrb r2, [r1] - cbz r2, strcpy_unalign_copy1byte - ldrb r4, [r1, #1] - cbz r4, strcpy_unalign_copy2bytes - - ldr r2, [r1], #4 - ldr r3, [r1], #4 - pld [r1, #64] - - tst r2, #0xff0000 - beq strcpy_copy3bytes - lsrs ip, r2, #24 - beq strcpy_copy4bytes - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_unalign2 - - .p2align 2 - // Can read 1 byte before possibly crossing a page. -strcpy_unalign1: - ldrb r2, [r1] - cbz r2, strcpy_unalign_copy1byte - - ldr r2, [r1], #4 - ldr r3, [r1], #4 - - pld [r1, #64] - - sub ip, r2, #0x01010101 - bic ip, ip, r2 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_first_register - - sub ip, r3, #0x01010101 - bic ip, ip, r3 - ands ip, ip, #0x80808080 - bne strcpy_zero_in_second_register - - strd r2, r3, [r0], #8 - b strcpy_unalign1 - -strcpy_unalign_copy1byte: - strb r2, [r0] - m_pop -strcpy_unalign_copy2bytes: - strb r2, [r0], #1 - strb r4, [r0] - m_pop -END(strcpy) +#define STRCPY +#include "string_copy.S" |