//===-- Portable optimization macros ----------------------------*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // This header file defines portable macros for performance optimization. #ifndef LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H #define LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H #include "src/__support/macros/attributes.h" // LIBC_INLINE #include "src/__support/macros/config.h" // LIBC_HAS_BUILTIN #include "src/__support/macros/properties/compiler.h" // LIBC_COMPILER_IS_CLANG // We use a template to implement likely/unlikely to make sure that we don't // accidentally pass an integer. namespace __llvm_libc::details { template LIBC_INLINE constexpr bool expects_bool_condition(T value, T expected) { return __builtin_expect(value, expected); } } // namespace __llvm_libc::details #define LIBC_LIKELY(x) __llvm_libc::details::expects_bool_condition(x, true) #define LIBC_UNLIKELY(x) __llvm_libc::details::expects_bool_condition(x, false) #if defined(LIBC_COMPILER_IS_CLANG) #define LIBC_LOOP_NOUNROLL _Pragma("nounroll") #elif defined(LIBC_COMPILER_IS_GCC) #define LIBC_LOOP_NOUNROLL _Pragma("GCC unroll 0") #else #error "Unhandled compiler" #endif #endif /* LLVM_LIBC_SRC_SUPPORT_MACROS_OPTIMIZATION_H */