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9b20c629fe
Add assembly-optimized implementations for 14 string/memory functions using word-at-a-time techniques (DETECTNULL, broadcast+XOR) and XLEN-adaptive macros for both RV32 and RV64: - memmove: direction check + forward tail to memcpy, reverse path with 16xSZREG unroll and shift-merge for misaligned src. - memcmp: word-granularity compare when both pointers share alignment, bytewise fallback for mismatched pointers. - memchr: broadcast target byte, XOR with each word, DETECTNULL to find matches. Counter-based bounds (no pointer overflow). - strlen: DETECTNULL word loop, constants loaded from .srodata. - strnlen: strlen with counter-based length limit. - strcpy/strncpy: word loop with DETECTNULL, zero-fill remainder for strncpy. strncpy reuses strcpy via #define USE_AS_STRNCPY. - stpcpy/stpncpy: reuse strcpy/strncpy via #define USE_AS_STPCPY. - strchr/strchrnul: broadcast+XOR detecting both target char and null simultaneously. strchrnul reuses strchr via #define. - strrchr: forward scan recording last match position. - strncmp: word-at-a-time compare with null detection and counter. - strcat: strlen(dst) then strcpy(dst_end, src) word-at-a-time. Each function is independently selectable via CONFIG_RISCV_<FUNC>, or all enabled together with CONFIG_RISCV_STRING_FUNCTION=y. Assisted-by: Claude Opus 5 (1M context) <noreply@anthropic.com> Signed-off-by: ganjing <ganjing@xiaomi.com>
27 lines
1.1 KiB
ArmAsm
27 lines
1.1 KiB
ArmAsm
/****************************************************************************
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* libs/libc/machine/risc-v/arch_stpcpy.S
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*
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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#include "libc.h"
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#define USE_AS_STPCPY
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#define STRCPY ARCH_LIBCFUN(stpcpy)
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#include "arch_strcpy.S"
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