| //===-- Implementation of bcmp --------------------------------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #ifndef LLVM_LIBC_SRC_STRING_MEMORY_UTILS_BCMP_IMPLEMENTATIONS_H |
| #define LLVM_LIBC_SRC_STRING_MEMORY_UTILS_BCMP_IMPLEMENTATIONS_H |
| |
| #include "src/__support/architectures.h" |
| #include "src/__support/common.h" |
| #include "src/string/memory_utils/elements.h" |
| |
| #include <stddef.h> // size_t |
| |
| namespace __llvm_libc { |
| |
| // Fixed-size difference between 'lhs' and 'rhs'. |
| template <typename Element> bool Differs(const char *lhs, const char *rhs) { |
| return !Element::Equals(lhs, rhs); |
| } |
| // Runtime-size difference between 'lhs' and 'rhs'. |
| template <typename Element> |
| bool Differs(const char *lhs, const char *rhs, size_t size) { |
| return !Element::Equals(lhs, rhs, size); |
| } |
| |
| static inline int inline_bcmp(const char *lhs, const char *rhs, size_t count) { |
| #if defined(LLVM_LIBC_ARCH_X86) |
| using namespace ::__llvm_libc::x86; |
| #elif defined(LLVM_LIBC_ARCH_AARCH64) |
| using namespace ::__llvm_libc::aarch64; |
| #else |
| using namespace ::__llvm_libc::scalar; |
| #endif |
| if (count == 0) |
| return 0; |
| if (count == 1) |
| return Differs<_1>(lhs, rhs); |
| if (count == 2) |
| return Differs<_2>(lhs, rhs); |
| if (count == 3) |
| return Differs<_3>(lhs, rhs); |
| if (count <= 8) |
| return Differs<HeadTail<_4>>(lhs, rhs, count); |
| if (count <= 16) |
| return Differs<HeadTail<_8>>(lhs, rhs, count); |
| if (count <= 32) |
| return Differs<HeadTail<_16>>(lhs, rhs, count); |
| if (count <= 64) |
| return Differs<HeadTail<_32>>(lhs, rhs, count); |
| if (count <= 128) |
| return Differs<HeadTail<_64>>(lhs, rhs, count); |
| return Differs<Align<_32>::Then<Loop<_32>>>(lhs, rhs, count); |
| } |
| |
| } // namespace __llvm_libc |
| |
| #endif // LLVM_LIBC_SRC_STRING_MEMORY_UTILS_BCMP_IMPLEMENTATIONS_H |