diff options
| author | 3gg <3gg@shellblade.net> | 2025-12-27 12:03:39 -0800 |
|---|---|---|
| committer | 3gg <3gg@shellblade.net> | 2025-12-27 12:03:39 -0800 |
| commit | 5a079a2d114f96d4847d1ee305d5b7c16eeec50e (patch) | |
| tree | 8926ab44f168acf787d8e19608857b3af0f82758 /contrib/SDL-3.2.8/src/stdlib/SDL_memset.c | |
Initial commit
Diffstat (limited to 'contrib/SDL-3.2.8/src/stdlib/SDL_memset.c')
| -rw-r--r-- | contrib/SDL-3.2.8/src/stdlib/SDL_memset.c | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/contrib/SDL-3.2.8/src/stdlib/SDL_memset.c b/contrib/SDL-3.2.8/src/stdlib/SDL_memset.c new file mode 100644 index 0000000..324f917 --- /dev/null +++ b/contrib/SDL-3.2.8/src/stdlib/SDL_memset.c | |||
| @@ -0,0 +1,139 @@ | |||
| 1 | /* | ||
| 2 | Simple DirectMedia Layer | ||
| 3 | Copyright (C) 1997-2025 Sam Lantinga <slouken@libsdl.org> | ||
| 4 | |||
| 5 | This software is provided 'as-is', without any express or implied | ||
| 6 | warranty. In no event will the authors be held liable for any damages | ||
| 7 | arising from the use of this software. | ||
| 8 | |||
| 9 | Permission is granted to anyone to use this software for any purpose, | ||
| 10 | including commercial applications, and to alter it and redistribute it | ||
| 11 | freely, subject to the following restrictions: | ||
| 12 | |||
| 13 | 1. The origin of this software must not be misrepresented; you must not | ||
| 14 | claim that you wrote the original software. If you use this software | ||
| 15 | in a product, an acknowledgment in the product documentation would be | ||
| 16 | appreciated but is not required. | ||
| 17 | 2. Altered source versions must be plainly marked as such, and must not be | ||
| 18 | misrepresented as being the original software. | ||
| 19 | 3. This notice may not be removed or altered from any source distribution. | ||
| 20 | */ | ||
| 21 | #include "SDL_internal.h" | ||
| 22 | |||
| 23 | |||
| 24 | #ifdef SDL_memset | ||
| 25 | #undef SDL_memset | ||
| 26 | #endif | ||
| 27 | #if SDL_DYNAMIC_API | ||
| 28 | #define SDL_memset SDL_memset_REAL | ||
| 29 | #endif | ||
| 30 | void *SDL_memset(SDL_OUT_BYTECAP(len) void *dst, int c, size_t len) | ||
| 31 | { | ||
| 32 | #if defined(__GNUC__) && (defined(HAVE_LIBC) && HAVE_LIBC) | ||
| 33 | return __builtin_memset(dst, c, len); | ||
| 34 | #elif defined(HAVE_MEMSET) | ||
| 35 | return memset(dst, c, len); | ||
| 36 | #else | ||
| 37 | size_t left; | ||
| 38 | Uint32 *dstp4; | ||
| 39 | Uint8 *dstp1 = (Uint8 *)dst; | ||
| 40 | Uint8 value1; | ||
| 41 | Uint32 value4; | ||
| 42 | |||
| 43 | // The value used in memset() is a byte, passed as an int | ||
| 44 | c &= 0xff; | ||
| 45 | |||
| 46 | /* The destination pointer needs to be aligned on a 4-byte boundary to | ||
| 47 | * execute a 32-bit set. Set first bytes manually if needed until it is | ||
| 48 | * aligned. */ | ||
| 49 | value1 = (Uint8)c; | ||
| 50 | while ((uintptr_t)dstp1 & 0x3) { | ||
| 51 | if (len--) { | ||
| 52 | *dstp1++ = value1; | ||
| 53 | } else { | ||
| 54 | return dst; | ||
| 55 | } | ||
| 56 | } | ||
| 57 | |||
| 58 | value4 = ((Uint32)c | ((Uint32)c << 8) | ((Uint32)c << 16) | ((Uint32)c << 24)); | ||
| 59 | dstp4 = (Uint32 *)dstp1; | ||
| 60 | left = (len % 4); | ||
| 61 | len /= 4; | ||
| 62 | while (len--) { | ||
| 63 | *dstp4++ = value4; | ||
| 64 | } | ||
| 65 | |||
| 66 | dstp1 = (Uint8 *)dstp4; | ||
| 67 | switch (left) { | ||
| 68 | case 3: | ||
| 69 | *dstp1++ = value1; | ||
| 70 | SDL_FALLTHROUGH; | ||
| 71 | case 2: | ||
| 72 | *dstp1++ = value1; | ||
| 73 | SDL_FALLTHROUGH; | ||
| 74 | case 1: | ||
| 75 | *dstp1++ = value1; | ||
| 76 | } | ||
| 77 | |||
| 78 | return dst; | ||
| 79 | #endif // HAVE_MEMSET | ||
| 80 | } | ||
| 81 | |||
| 82 | // Note that memset() is a byte assignment and this is a 32-bit assignment, so they're not directly equivalent. | ||
| 83 | void *SDL_memset4(void *dst, Uint32 val, size_t dwords) | ||
| 84 | { | ||
| 85 | #if defined(__APPLE__) && defined(HAVE_STRING_H) | ||
| 86 | memset_pattern4(dst, &val, dwords * 4); | ||
| 87 | #elif defined(__GNUC__) && defined(__i386__) | ||
| 88 | int u0, u1, u2; | ||
| 89 | __asm__ __volatile__( | ||
| 90 | "cld \n\t" | ||
| 91 | "rep ; stosl \n\t" | ||
| 92 | : "=&D"(u0), "=&a"(u1), "=&c"(u2) | ||
| 93 | : "0"(dst), "1"(val), "2"(SDL_static_cast(Uint32, dwords)) | ||
| 94 | : "memory"); | ||
| 95 | #else | ||
| 96 | size_t _n = (dwords + 3) / 4; | ||
| 97 | Uint32 *_p = SDL_static_cast(Uint32 *, dst); | ||
| 98 | Uint32 _val = (val); | ||
| 99 | if (dwords == 0) { | ||
| 100 | return dst; | ||
| 101 | } | ||
| 102 | switch (dwords % 4) { | ||
| 103 | case 0: | ||
| 104 | do { | ||
| 105 | *_p++ = _val; | ||
| 106 | SDL_FALLTHROUGH; | ||
| 107 | case 3: | ||
| 108 | *_p++ = _val; | ||
| 109 | SDL_FALLTHROUGH; | ||
| 110 | case 2: | ||
| 111 | *_p++ = _val; | ||
| 112 | SDL_FALLTHROUGH; | ||
| 113 | case 1: | ||
| 114 | *_p++ = _val; | ||
| 115 | } while (--_n); | ||
| 116 | } | ||
| 117 | #endif | ||
| 118 | return dst; | ||
| 119 | } | ||
| 120 | |||
| 121 | /* The optimizer on Visual Studio 2005 and later generates memcpy() and memset() calls. | ||
| 122 | We will provide our own implementation if we're not building with a C runtime. */ | ||
| 123 | #ifndef HAVE_LIBC | ||
| 124 | // NOLINTNEXTLINE(readability-redundant-declaration) | ||
| 125 | extern void *memset(void *dst, int c, size_t len); | ||
| 126 | #if defined(_MSC_VER) && !defined(__INTEL_LLVM_COMPILER) | ||
| 127 | #pragma intrinsic(memset) | ||
| 128 | #endif | ||
| 129 | |||
| 130 | #if defined(_MSC_VER) && !defined(__clang__) | ||
| 131 | #pragma function(memset) | ||
| 132 | #endif | ||
| 133 | // NOLINTNEXTLINE(readability-inconsistent-declaration-parameter-name) | ||
| 134 | void *memset(void *dst, int c, size_t len) | ||
| 135 | { | ||
| 136 | return SDL_memset(dst, c, len); | ||
| 137 | } | ||
| 138 | #endif // !HAVE_LIBC | ||
| 139 | |||
