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Diffstat (limited to 'newlib/libc/machine/aarch64/strchrnul.S')
| -rw-r--r-- | newlib/libc/machine/aarch64/strchrnul.S | 149 |
1 files changed, 0 insertions, 149 deletions
diff --git a/newlib/libc/machine/aarch64/strchrnul.S b/newlib/libc/machine/aarch64/strchrnul.S deleted file mode 100644 index a0ac13b7f..000000000 --- a/newlib/libc/machine/aarch64/strchrnul.S +++ /dev/null @@ -1,149 +0,0 @@ -/* - strchrnul - find a character or nul in a string - - Copyright (c) 2014, ARM Limited - 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. - * Neither the name of the company nor the names of its contributors - may be used to endorse or promote products derived from this - software without specific prior written permission. - - 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 - HOLDER 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. */ - -#if (defined (__OPTIMIZE_SIZE__) || defined (PREFER_SIZE_OVER_SPEED)) -/* See strchrnul-stub.c */ -#else - -/* Assumptions: - * - * ARMv8-a, AArch64 - * Neon Available. - */ - -/* Arguments and results. */ -#define srcin x0 -#define chrin w1 - -#define result x0 - -#define src x2 -#define tmp1 x3 -#define wtmp2 w4 -#define tmp3 x5 - -#define vrepchr v0 -#define vdata1 v1 -#define vdata2 v2 -#define vhas_nul1 v3 -#define vhas_nul2 v4 -#define vhas_chr1 v5 -#define vhas_chr2 v6 -#define vrepmask v7 -#define vend1 v16 - -/* Core algorithm. - - For each 32-byte hunk we calculate a 64-bit syndrome value, with - two bits per byte (LSB is always in bits 0 and 1, for both big - and little-endian systems). For each tuple, bit 0 is set iff - the relevant byte matched the requested character or nul. Since the - bits in the syndrome reflect exactly the order in which things occur - in the original string a count_trailing_zeros() operation will - identify exactly which byte is causing the termination. */ - -/* Locals and temporaries. */ - - .macro def_fn f p2align=0 - .text - .p2align \p2align - .global \f - .type \f, %function -\f: - .endm - -def_fn strchrnul - /* Magic constant 0x40100401 to allow us to identify which lane - matches the termination condition. */ - mov wtmp2, #0x0401 - movk wtmp2, #0x4010, lsl #16 - dup vrepchr.16b, chrin - bic src, srcin, #31 /* Work with aligned 32-byte hunks. */ - dup vrepmask.4s, wtmp2 - ands tmp1, srcin, #31 - b.eq .Lloop - - /* Input string is not 32-byte aligned. Rather than forcing - the padding bytes to a safe value, we calculate the syndrome - for all the bytes, but then mask off those bits of the - syndrome that are related to the padding. */ - ld1 {vdata1.16b, vdata2.16b}, [src], #32 - neg tmp1, tmp1 - cmeq vhas_nul1.16b, vdata1.16b, #0 - cmeq vhas_chr1.16b, vdata1.16b, vrepchr.16b - cmeq vhas_nul2.16b, vdata2.16b, #0 - cmeq vhas_chr2.16b, vdata2.16b, vrepchr.16b - orr vhas_chr1.16b, vhas_chr1.16b, vhas_nul1.16b - orr vhas_chr2.16b, vhas_chr2.16b, vhas_nul2.16b - and vhas_chr1.16b, vhas_chr1.16b, vrepmask.16b - and vhas_chr2.16b, vhas_chr2.16b, vrepmask.16b - lsl tmp1, tmp1, #1 - addp vend1.16b, vhas_chr1.16b, vhas_chr2.16b // 256->128 - mov tmp3, #~0 - addp vend1.16b, vend1.16b, vend1.16b // 128->64 - lsr tmp1, tmp3, tmp1 - - mov tmp3, vend1.2d[0] - bic tmp1, tmp3, tmp1 // Mask padding bits. - cbnz tmp1, .Ltail - -.Lloop: - ld1 {vdata1.16b, vdata2.16b}, [src], #32 - cmeq vhas_nul1.16b, vdata1.16b, #0 - cmeq vhas_chr1.16b, vdata1.16b, vrepchr.16b - cmeq vhas_nul2.16b, vdata2.16b, #0 - cmeq vhas_chr2.16b, vdata2.16b, vrepchr.16b - /* Use a fast check for the termination condition. */ - orr vhas_chr1.16b, vhas_nul1.16b, vhas_chr1.16b - orr vhas_chr2.16b, vhas_nul2.16b, vhas_chr2.16b - orr vend1.16b, vhas_chr1.16b, vhas_chr2.16b - addp vend1.2d, vend1.2d, vend1.2d - mov tmp1, vend1.2d[0] - cbz tmp1, .Lloop - - /* Termination condition found. Now need to establish exactly why - we terminated. */ - and vhas_chr1.16b, vhas_chr1.16b, vrepmask.16b - and vhas_chr2.16b, vhas_chr2.16b, vrepmask.16b - addp vend1.16b, vhas_chr1.16b, vhas_chr2.16b // 256->128 - addp vend1.16b, vend1.16b, vend1.16b // 128->64 - - mov tmp1, vend1.2d[0] -.Ltail: - /* Count the trailing zeros, by bit reversing... */ - rbit tmp1, tmp1 - /* Re-bias source. */ - sub src, src, #32 - clz tmp1, tmp1 /* ... and counting the leading zeros. */ - /* tmp1 is twice the offset into the fragment. */ - add result, src, tmp1, lsr #1 - ret - - .size strchrnul, . - strchrnul -#endif |