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@@ -0,0 +1,79 @@
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+/*
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+ Simple DirectMedia Layer
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+ Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org>
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+
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+ This software is provided 'as-is', without any express or implied
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+ warranty. In no event will the authors be held liable for any damages
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+ arising from the use of this software.
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+
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+ Permission is granted to anyone to use this software for any purpose,
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+ including commercial applications, and to alter it and redistribute it
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+ freely, subject to the following restrictions:
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+
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+ 1. The origin of this software must not be misrepresented; you must not
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+ claim that you wrote the original software. If you use this software
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+ in a product, an acknowledgment in the product documentation would be
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+ appreciated but is not required.
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+ 2. Altered source versions must be plainly marked as such, and must not be
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+ misrepresented as being the original software.
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+ 3. This notice may not be removed or altered from any source distribution.
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+*/
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+
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+#include "../SDL_internal.h"
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+
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+/* This file contains a portable memcpy manipulation function for SDL */
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+
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+void *
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+SDL_memcpy(SDL_OUT_BYTECAP(len) void *dst, SDL_IN_BYTECAP(len) const void *src, size_t len)
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+{
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+#ifdef __GNUC__
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+ /* Presumably this is well tuned for speed.
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+ On my machine this is twice as fast as the C code below.
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+ */
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+ return __builtin_memcpy(dst, src, len);
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+#elif defined(HAVE_MEMCPY)
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+ return memcpy(dst, src, len);
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+#elif defined(HAVE_BCOPY)
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+ bcopy(src, dst, len);
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+ return dst;
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+#else
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+ /* GCC 4.9.0 with -O3 will generate movaps instructions with the loop
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+ using Uint32* pointers, so we need to make sure the pointers are
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+ aligned before we loop using them.
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+ */
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+ if (((uintptr_t)src & 0x3) || ((uintptr_t)dst & 0x3)) {
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+ /* Do an unaligned byte copy */
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+ Uint8 *srcp1 = (Uint8 *)src;
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+ Uint8 *dstp1 = (Uint8 *)dst;
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+
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+ while (len--) {
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+ *dstp1++ = *srcp1++;
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+ }
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+ } else {
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+ size_t left = (len % 4);
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+ Uint32 *srcp4, *dstp4;
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+ Uint8 *srcp1, *dstp1;
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+
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+ srcp4 = (Uint32 *) src;
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+ dstp4 = (Uint32 *) dst;
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+ len /= 4;
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+ while (len--) {
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+ *dstp4++ = *srcp4++;
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+ }
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+
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+ srcp1 = (Uint8 *) srcp4;
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+ dstp1 = (Uint8 *) dstp4;
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+ switch (left) {
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+ case 3:
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+ *dstp1++ = *srcp1++;
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+ case 2:
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+ *dstp1++ = *srcp1++;
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+ case 1:
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+ *dstp1++ = *srcp1++;
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+ }
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+ }
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+ return dst;
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+#endif /* __GNUC__ */
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+}
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+
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+/* vi: set ts=4 sw=4 expandtab: */
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