1 //===-- Bcmp implementation for aarch64 -------------------------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 #ifndef LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_BCMP_H
9 #define LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_BCMP_H
10
11 #include "src/__support/macros/attributes.h" // LIBC_INLINE
12 #include "src/__support/macros/config.h"
13 #include "src/__support/macros/optimization.h" // LIBC_UNLIKELY
14 #include "src/string/memory_utils/op_aarch64.h"
15 #include "src/string/memory_utils/op_generic.h"
16 #include "src/string/memory_utils/utils.h" // Ptr, CPtr
17
18 #include <stddef.h> // size_t
19
20 namespace LIBC_NAMESPACE_DECL {
21
inline_bcmp_aarch64(CPtr p1,CPtr p2,size_t count)22 [[maybe_unused]] LIBC_INLINE BcmpReturnType inline_bcmp_aarch64(CPtr p1,
23 CPtr p2,
24 size_t count) {
25 if (LIBC_LIKELY(count <= 32)) {
26 if (LIBC_UNLIKELY(count >= 16)) {
27 return aarch64::Bcmp<16>::head_tail(p1, p2, count);
28 }
29 switch (count) {
30 case 0:
31 return BcmpReturnType::zero();
32 case 1:
33 return generic::Bcmp<uint8_t>::block(p1, p2);
34 case 2:
35 return generic::Bcmp<uint16_t>::block(p1, p2);
36 case 3:
37 return generic::Bcmp<uint16_t>::head_tail(p1, p2, count);
38 case 4:
39 return generic::Bcmp<uint32_t>::block(p1, p2);
40 case 5:
41 case 6:
42 case 7:
43 return generic::Bcmp<uint32_t>::head_tail(p1, p2, count);
44 case 8:
45 return generic::Bcmp<uint64_t>::block(p1, p2);
46 case 9:
47 case 10:
48 case 11:
49 case 12:
50 case 13:
51 case 14:
52 case 15:
53 return generic::Bcmp<uint64_t>::head_tail(p1, p2, count);
54 }
55 }
56
57 if (count <= 64)
58 return aarch64::Bcmp<32>::head_tail(p1, p2, count);
59
60 // Aligned loop if > 256, otherwise normal loop
61 if (LIBC_UNLIKELY(count > 256)) {
62 if (auto value = aarch64::Bcmp<32>::block(p1, p2))
63 return value;
64 align_to_next_boundary<16, Arg::P1>(p1, p2, count);
65 }
66 return aarch64::Bcmp<32>::loop_and_tail(p1, p2, count);
67 }
68
69 } // namespace LIBC_NAMESPACE_DECL
70
71 #endif // LIBC_SRC_STRING_MEMORY_UTILS_AARCH64_INLINE_BCMP_H
72