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The C and C++ Include Header Files

/usr/include/python3.12/ImagingUtils.h


$ cat -n /usr/include/python3.12/ImagingUtils.h

     1	#ifdef WORDS_BIGENDIAN
     2	#define MAKE_UINT32(u0, u1, u2, u3) \
     3	    ((UINT32)(u3) | ((UINT32)(u2) << 8) | ((UINT32)(u1) << 16) | ((UINT32)(u0) << 24))
     4	#define MASK_UINT32_CHANNEL_0 0xff000000
     5	#define MASK_UINT32_CHANNEL_1 0x00ff0000
     6	#define MASK_UINT32_CHANNEL_2 0x0000ff00
     7	#define MASK_UINT32_CHANNEL_3 0x000000ff
     8	#else
     9	#define MAKE_UINT32(u0, u1, u2, u3) \
    10	    ((UINT32)(u0) | ((UINT32)(u1) << 8) | ((UINT32)(u2) << 16) | ((UINT32)(u3) << 24))
    11	#define MASK_UINT32_CHANNEL_0 0x000000ff
    12	#define MASK_UINT32_CHANNEL_1 0x0000ff00
    13	#define MASK_UINT32_CHANNEL_2 0x00ff0000
    14	#define MASK_UINT32_CHANNEL_3 0xff000000
    15	#endif
    16	
    17	#define SHIFTFORDIV255(a) ((((a) >> 8) + a) >> 8)
    18	
    19	/* like (a * b + 127) / 255), but much faster on most platforms */
    20	#define MULDIV255(a, b, tmp) (tmp = (a) * (b) + 128, SHIFTFORDIV255(tmp))
    21	
    22	#define DIV255(a, tmp) (tmp = (a) + 128, SHIFTFORDIV255(tmp))
    23	
    24	#define BLEND(mask, in1, in2, tmp1) DIV255(in1 *(255 - mask) + in2 * mask, tmp1)
    25	
    26	#define PREBLEND(mask, in1, in2, tmp1) (MULDIV255(in1, (255 - mask), tmp1) + in2)
    27	
    28	#define CLIP8(v) ((v) <= 0 ? 0 : (v) < 256 ? (v) : 255)
    29	
    30	/* This is to work around a bug in GCC prior 4.9 in 64 bit mode.
    31	   GCC generates code with partial dependency which is 3 times slower.
    32	   See: https://stackoverflow.com/a/26588074/253146 */
    33	#if defined(__x86_64__) && defined(__SSE__) && !defined(__NO_INLINE__) && \
    34	    !defined(__clang__) && defined(GCC_VERSION) && (GCC_VERSION < 40900)
    35	static float __attribute__((always_inline)) inline _i2f(int v) {
    36	    float x;
    37	    __asm__("xorps %0, %0; cvtsi2ss %1, %0" : "=x"(x) : "r"(v));
    38	    return x;
    39	}
    40	#else
    41	static float inline _i2f(int v) { return (float)v; }
    42	#endif