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--- include/allegro/inline/fmaths.inl.orig Sun Jun 5 18:23:46 2005
+++ include/allegro/inline/fmaths.inl Thu Aug 11 18:53:53 2005
@@ -103,40 +103,11 @@
AL_INLINE(fixed, fixmul, (fixed x, fixed y),
{
- /* In benchmarks conducted circa May 2005 we found that, in the main:
- * - IA32 machines performed faster with one implementation;
- * - AMD64 and G4 machines performed faster with another implementation.
- *
- * Benchmarks were mainly done with differing versions of gcc.
- * Results varied with other compilers, optimisation levels, etc.
- * so this is not optimal, though a tenable compromise.
- */
- #if (defined ALLEGRO_I386) || (!defined LONG_LONG)
-
- fixed sign = (x^y) & 0x80000000;
- int mask_x = x >> 31;
- int mask_y = y >> 31;
- int mask_result = sign >> 31;
- fixed result;
-
- x = (x^mask_x) - mask_x;
- y = (y^mask_y) - mask_y;
-
- result = ((y >> 8)*(x >> 8) +
- (((y >> 8)*(x&0xff)) >> 8) +
- (((x >> 8)*(y&0xff)) >> 8));
-
- return (result^mask_result) - mask_result;
-
- #else
-
LONG_LONG lx = x;
LONG_LONG ly = y;
LONG_LONG lres = (lx*ly)>>16;
int res = lres;
return res;
-
- #endif
})
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