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-rw-r--r--dependencies/include/SDL/SDL_bits.h126
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diff --git a/dependencies/include/SDL/SDL_bits.h b/dependencies/include/SDL/SDL_bits.h
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+++ b/dependencies/include/SDL/SDL_bits.h
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+/*
+ Simple DirectMedia Layer
+ Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org>
+
+ This software is provided 'as-is', without any express or implied
+ warranty. In no event will the authors be held liable for any damages
+ arising from the use of this software.
+
+ Permission is granted to anyone to use this software for any purpose,
+ including commercial applications, and to alter it and redistribute it
+ freely, subject to the following restrictions:
+
+ 1. The origin of this software must not be misrepresented; you must not
+ claim that you wrote the original software. If you use this software
+ in a product, an acknowledgment in the product documentation would be
+ appreciated but is not required.
+ 2. Altered source versions must be plainly marked as such, and must not be
+ misrepresented as being the original software.
+ 3. This notice may not be removed or altered from any source distribution.
+*/
+
+/**
+ * \file SDL_bits.h
+ *
+ * Functions for fiddling with bits and bitmasks.
+ */
+
+#ifndef SDL_bits_h_
+#define SDL_bits_h_
+
+#include "SDL_stdinc.h"
+
+#include "begin_code.h"
+/* Set up for C function definitions, even when using C++ */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * \file SDL_bits.h
+ */
+
+/**
+ * Get the index of the most significant bit. Result is undefined when called
+ * with 0. This operation can also be stated as "count leading zeroes" and
+ * "log base 2".
+ *
+ * \return the index of the most significant bit, or -1 if the value is 0.
+ */
+#if defined(__WATCOMC__) && defined(__386__)
+extern __inline int _SDL_bsr_watcom(Uint32);
+#pragma aux _SDL_bsr_watcom = \
+ "bsr eax, eax" \
+ parm [eax] nomemory \
+ value [eax] \
+ modify exact [eax] nomemory;
+#endif
+
+SDL_FORCE_INLINE int
+SDL_MostSignificantBitIndex32(Uint32 x)
+{
+#if defined(__GNUC__) && (__GNUC__ >= 4 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 4))
+ /* Count Leading Zeroes builtin in GCC.
+ * http://gcc.gnu.org/onlinedocs/gcc-4.3.4/gcc/Other-Builtins.html
+ */
+ if (x == 0) {
+ return -1;
+ }
+ return 31 - __builtin_clz(x);
+#elif defined(__WATCOMC__) && defined(__386__)
+ if (x == 0) {
+ return -1;
+ }
+ return _SDL_bsr_watcom(x);
+#elif defined(_MSC_VER)
+ unsigned long index;
+ if (_BitScanReverse(&index, x)) {
+ return index;
+ }
+ return -1;
+#else
+ /* Based off of Bit Twiddling Hacks by Sean Eron Anderson
+ * <seander@cs.stanford.edu>, released in the public domain.
+ * http://graphics.stanford.edu/~seander/bithacks.html#IntegerLog
+ */
+ const Uint32 b[] = {0x2, 0xC, 0xF0, 0xFF00, 0xFFFF0000};
+ const int S[] = {1, 2, 4, 8, 16};
+
+ int msbIndex = 0;
+ int i;
+
+ if (x == 0) {
+ return -1;
+ }
+
+ for (i = 4; i >= 0; i--)
+ {
+ if (x & b[i])
+ {
+ x >>= S[i];
+ msbIndex |= S[i];
+ }
+ }
+
+ return msbIndex;
+#endif
+}
+
+SDL_FORCE_INLINE SDL_bool
+SDL_HasExactlyOneBitSet32(Uint32 x)
+{
+ if (x && !(x & (x - 1))) {
+ return SDL_TRUE;
+ }
+ return SDL_FALSE;
+}
+
+/* Ends C function definitions when using C++ */
+#ifdef __cplusplus
+}
+#endif
+#include "close_code.h"
+
+#endif /* SDL_bits_h_ */
+
+/* vi: set ts=4 sw=4 expandtab: */