xiaoxiang781216 commented on code in PR #18347: URL: https://github.com/apache/nuttx/pull/18347#discussion_r2850503139
########## include/nuttx/lib/stdbit.h: ########## @@ -0,0 +1,383 @@ +/**************************************************************************** + * include/nuttx/lib/stdbit.h + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to you under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + ****************************************************************************/ + +#ifndef __INCLUDE_NUTTX_LIB_STDBIT_H +#define __INCLUDE_NUTTX_LIB_STDBIT_H + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <nuttx/compiler.h> +#include <stdint.h> + +#ifdef CONFIG_ARCH_STDBIT_H +# include <arch/stdbit.h> +#else + +/**************************************************************************** + * Generic C23 stdbit implementation (CONFIG_LIBC_STDBIT_GENERIC). + * Requires __builtin_clz, __builtin_ctz, __builtin_popcount (and ll + * variants). If the toolchain does not provide them, enable the + * corresponding CONFIG_HAVE_BUILTIN_* in nuttx/compiler.h or do not + * use LIBC_STDBIT_GENERIC. + ****************************************************************************/ + +# if !defined(CONFIG_HAVE_BUILTIN_CLZ) || \ + !defined(CONFIG_HAVE_BUILTIN_CTZ) || \ + !defined(CONFIG_HAVE_BUILTIN_POPCOUNT) +# error "Generic stdbit requires CONFIG_HAVE_BUILTIN_CLZ, CTZ, POPCOUNT" +# endif + +# if defined(CONFIG_HAVE_LONG_LONG) && \ + !defined(CONFIG_HAVE_BUILTIN_POPCOUNTLL) +# error "Generic stdbit 64-bit requires CONFIG_HAVE_BUILTIN_POPCOUNTLL" +# endif + +/**************************************************************************** + * C23 endianness macros (reuse LITTLE_ENDIAN/BIG_ENDIAN from sys/endian.h) + ****************************************************************************/ + +# include <sys/endian.h> Review Comment: not fix yet ########## include/nuttx/lib/stdbit.h: ########## @@ -0,0 +1,383 @@ +/**************************************************************************** + * include/nuttx/lib/stdbit.h + * + * SPDX-License-Identifier: Apache-2.0 + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to you under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + ****************************************************************************/ + +#ifndef __INCLUDE_NUTTX_LIB_STDBIT_H +#define __INCLUDE_NUTTX_LIB_STDBIT_H + +/**************************************************************************** + * Included Files + ****************************************************************************/ + +#include <nuttx/config.h> +#include <nuttx/compiler.h> +#include <stdint.h> + +#ifdef CONFIG_ARCH_STDBIT_H +# include <arch/stdbit.h> +#else + +/**************************************************************************** + * Generic C23 stdbit implementation (CONFIG_LIBC_STDBIT_GENERIC). + * Requires __builtin_clz, __builtin_ctz, __builtin_popcount (and ll + * variants). If the toolchain does not provide them, enable the + * corresponding CONFIG_HAVE_BUILTIN_* in nuttx/compiler.h or do not + * use LIBC_STDBIT_GENERIC. + ****************************************************************************/ + +# if !defined(CONFIG_HAVE_BUILTIN_CLZ) || \ + !defined(CONFIG_HAVE_BUILTIN_CTZ) || \ + !defined(CONFIG_HAVE_BUILTIN_POPCOUNT) +# error "Generic stdbit requires CONFIG_HAVE_BUILTIN_CLZ, CTZ, POPCOUNT" +# endif + +# if defined(CONFIG_HAVE_LONG_LONG) && \ + !defined(CONFIG_HAVE_BUILTIN_POPCOUNTLL) +# error "Generic stdbit 64-bit requires CONFIG_HAVE_BUILTIN_POPCOUNTLL" +# endif + +/**************************************************************************** + * C23 endianness macros (reuse LITTLE_ENDIAN/BIG_ENDIAN from sys/endian.h) + ****************************************************************************/ + +# include <sys/endian.h> +# define __STDC_ENDIAN_LITTLE__ LITTLE_ENDIAN +# define __STDC_ENDIAN_BIG__ BIG_ENDIAN +# define __STDC_ENDIAN_NATIVE__ BYTE_ORDER + +/**************************************************************************** + * Leading / trailing zeros (C23: zero input returns bit width) + ****************************************************************************/ + +# define stdc_leading_zeros_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0 ? 8 : \ + __builtin_clz((unsigned)(x) << 24))) +# define stdc_leading_zeros_us(x) \ + ((unsigned int)((unsigned short)(x) == 0 ? 16 : \ + __builtin_clz((unsigned)(x) << 16))) +# define stdc_leading_zeros_ui(x) \ + ((unsigned int)((x) == 0 ? 32 : __builtin_clz(x))) +# define stdc_leading_zeros_ul(x) \ + ((unsigned int)((x) == 0 ? (8*sizeof(unsigned long)) : __builtin_clzl(x))) +# define stdc_leading_zeros_ull(x) \ + ((unsigned int)((x) == 0 ? (8*sizeof(unsigned long long)) : __builtin_clzll(x))) + +# define stdc_trailing_zeros_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0 ? 8 : __builtin_ctz((unsigned)(x)))) +# define stdc_trailing_zeros_us(x) \ + ((unsigned int)((unsigned short)(x) == 0 ? 16 : __builtin_ctz((unsigned)(x)))) +# define stdc_trailing_zeros_ui(x) \ + ((unsigned int)((x) == 0 ? 32 : __builtin_ctz(x))) +# define stdc_trailing_zeros_ul(x) \ + ((unsigned int)((x) == 0 ? (8*sizeof(unsigned long)) : __builtin_ctzl(x))) +# define stdc_trailing_zeros_ull(x) \ + ((unsigned int)((x) == 0 ? (8*sizeof(unsigned long long)) : __builtin_ctzll(x))) + +/**************************************************************************** + * Leading / trailing ones (C23: zero input returns 0) + ****************************************************************************/ + +# define stdc_leading_ones_uc(x) stdc_leading_zeros_uc((unsigned char)~(x)) +# define stdc_leading_ones_us(x) stdc_leading_zeros_us((unsigned short)~(x)) +# define stdc_leading_ones_ui(x) stdc_leading_zeros_ui(~(x)) +# define stdc_leading_ones_ul(x) stdc_leading_zeros_ul(~(x)) +# define stdc_leading_ones_ull(x) stdc_leading_zeros_ull(~(x)) + +# define stdc_trailing_ones_uc(x) stdc_trailing_zeros_uc((unsigned char)~(x)) +# define stdc_trailing_ones_us(x) stdc_trailing_zeros_us((unsigned short)~(x)) +# define stdc_trailing_ones_ui(x) stdc_trailing_zeros_ui(~(x)) +# define stdc_trailing_ones_ul(x) stdc_trailing_zeros_ul(~(x)) +# define stdc_trailing_ones_ull(x) stdc_trailing_zeros_ull(~(x)) + +/**************************************************************************** + * First leading zero/one (bit index from MSB; C23: 0 returns bit width) + ****************************************************************************/ + +# define stdc_first_leading_zero_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0xFF ? 0 : stdc_leading_ones_uc(x) + 1)) +# define stdc_first_leading_zero_us(x) \ + ((unsigned int)((unsigned short)(x) == 0xFFFF ? 0 : stdc_leading_ones_us(x) + 1)) +# define stdc_first_leading_zero_ui(x) \ + ((unsigned int)((x) == ~0u ? 0 : stdc_leading_ones_ui(x) + 1)) +# define stdc_first_leading_zero_ul(x) \ + ((unsigned int)((x) == ~0ul ? 0 : stdc_leading_ones_ul(x) + 1)) +# define stdc_first_leading_zero_ull(x) \ + ((unsigned int)((x) == ~0ull ? 0 : stdc_leading_ones_ull(x) + 1)) + +# define stdc_first_leading_one_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0 ? 0 : stdc_leading_zeros_uc(x) + 1)) +# define stdc_first_leading_one_us(x) \ + ((unsigned int)((unsigned short)(x) == 0 ? 0 : stdc_leading_zeros_us(x) + 1)) +# define stdc_first_leading_one_ui(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_leading_zeros_ui(x) + 1)) +# define stdc_first_leading_one_ul(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_leading_zeros_ul(x) + 1)) +# define stdc_first_leading_one_ull(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_leading_zeros_ull(x) + 1)) + +/**************************************************************************** + * First trailing zero/one (bit index from LSB; C23: 0 returns bit width) + ****************************************************************************/ + +# define stdc_first_trailing_zero_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0xFF ? 0 : stdc_trailing_ones_uc(x) + 1)) +# define stdc_first_trailing_zero_us(x) \ + ((unsigned int)((unsigned short)(x) == 0xFFFF ? 0 : stdc_trailing_ones_us(x) + 1)) +# define stdc_first_trailing_zero_ui(x) \ + ((unsigned int)((x) == ~0u ? 0 : stdc_trailing_ones_ui(x) + 1)) +# define stdc_first_trailing_zero_ul(x) \ + ((unsigned int)((x) == ~0ul ? 0 : stdc_trailing_ones_ul(x) + 1)) +# define stdc_first_trailing_zero_ull(x) \ + ((unsigned int)((x) == ~0ull ? 0 : stdc_trailing_ones_ull(x) + 1)) + +# define stdc_first_trailing_one_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0 ? 0 : stdc_trailing_zeros_uc(x) + 1)) +# define stdc_first_trailing_one_us(x) \ + ((unsigned int)((unsigned short)(x) == 0 ? 0 : stdc_trailing_zeros_us(x) + 1)) +# define stdc_first_trailing_one_ui(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_trailing_zeros_ui(x) + 1)) +# define stdc_first_trailing_one_ul(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_trailing_zeros_ul(x) + 1)) +# define stdc_first_trailing_one_ull(x) \ + ((unsigned int)((x) == 0 ? 0 : stdc_trailing_zeros_ull(x) + 1)) + +/**************************************************************************** + * Count zeros / ones + ****************************************************************************/ + +# define stdc_count_ones_uc(x) \ + ((unsigned int)__builtin_popcount((unsigned)(x))) +# define stdc_count_ones_us(x) \ + ((unsigned int)__builtin_popcount((unsigned)(x))) +# define stdc_count_ones_ui(x) ((unsigned int)__builtin_popcount(x)) +# define stdc_count_ones_ul(x) ((unsigned int)__builtin_popcountl(x)) +# define stdc_count_ones_ull(x) ((unsigned int)__builtin_popcountll(x)) + +# define stdc_count_zeros_uc(x) ((unsigned int)(8 - stdc_count_ones_uc(x))) +# define stdc_count_zeros_us(x) ((unsigned int)(16 - stdc_count_ones_us(x))) +# define stdc_count_zeros_ui(x) ((unsigned int)(32 - stdc_count_ones_ui(x))) +# define stdc_count_zeros_ul(x) \ + ((unsigned int)((8*sizeof(unsigned long)) - stdc_count_ones_ul(x))) +# define stdc_count_zeros_ull(x) \ + ((unsigned int)((8*sizeof(unsigned long long)) - stdc_count_ones_ull(x))) + +/**************************************************************************** + * Single-bit test, bit width, bit floor, bit ceil + ****************************************************************************/ + +# define stdc_has_single_bit_uc(x) (stdc_count_ones_uc(x) == 1) +# define stdc_has_single_bit_us(x) (stdc_count_ones_us(x) == 1) +# define stdc_has_single_bit_ui(x) (stdc_count_ones_ui(x) == 1) +# define stdc_has_single_bit_ul(x) (stdc_count_ones_ul(x) == 1) +# define stdc_has_single_bit_ull(x) (stdc_count_ones_ull(x) == 1) + +# define stdc_bit_width_uc(x) \ + ((unsigned int)((unsigned char)(x) == 0 ? 0 : 8 - stdc_leading_zeros_uc(x))) Review Comment: not change yet -- This is an automated message from the Apache Git Service. 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