the optimized UNCLAMPED_FLOAT_TO_UBYTE macro was broken

src/mesa/main/imports.h

@@ -8,9 +8,9 @@
 
 /*
  * Mesa 3-D graphics library
- * Version:  5.1
+ * Version:  6.0
  *
- * Copyright (C) 1999-2003  Brian Paul   All Rights Reserved.
+ * Copyright (C) 1999-2004  Brian Paul   All Rights Reserved.
  *
  * Permission is hereby granted, free of charge, to any person obtaining a
  * copy of this software and associated documentation files (the "Software"),
@@ -510,8 +510,8 @@ static INLINE int iceil(float f)
 
 
 /***
- *** UNCLAMPED_FLOAT_TO_UBYTE: map float from {0,1} to ubyte in [0,255]
- *** CLAMPED_FLOAT_TO_UBYTE: map float in [0,1] to ubyte in [0,255]
+ *** UNCLAMPED_FLOAT_TO_UBYTE: clamp float to [0,1] and map to ubyte in [0,255]
+ *** CLAMPED_FLOAT_TO_UBYTE: map float known to be in [0,1] to ubyte in [0,255]
  ***/
 #if defined(USE_IEEE) && !defined(DEBUG)
 #define IEEE_0996 0x3f7f0000	/* 0.996 or so */
@@ -522,13 +522,21 @@ static INLINE int iceil(float f)
         do {								\
            fi_type __tmp;						\
            __tmp.f = (F);						\
-           UB = ((__tmp.i >= IEEE_0996)					\
-               ? ((GLint)__tmp.i < 0) ? (GLubyte)0 : (GLubyte)255	\
-               : (__tmp.f = __tmp.f*(255.0F/256.0F) + 32768.0F,		\
-                  (GLubyte)__tmp.i));					\
+           if (__tmp.i < 0)						\
+              UB = (GLubyte) 0;						\
+           else if (__tmp.i >= IEEE_0996)				\
+              UB = (GLubyte) 255;					\
+           else {							\
+              __tmp.f = __tmp.f * (255.0F/256.0F) + 32768.0F;		\
+              UB = (GLubyte) __tmp.i;					\
+           }								\
+        } while (0)
+#define CLAMPED_FLOAT_TO_UBYTE(UB, F)					\
+        do {								\
+           fi_type __tmp;						\
+           __tmp.f = (F) * (255.0F/256.0F) + 32768.0F;			\
+           UB = (GLubyte) __tmp.i;					\
         } while (0)
-#define CLAMPED_FLOAT_TO_UBYTE(ub, f) \
-        UNCLAMPED_FLOAT_TO_UBYTE(ub, f)
 #else
 #define UNCLAMPED_FLOAT_TO_UBYTE(ub, f) \
 	ub = ((GLubyte) IROUND(CLAMP((f), 0.0F, 1.0F) * 255.0F))