mesa: Replace IS_NEGATIVE(x) with x < 0.0f.

I only made IS_NEGATIVE(x) use signbit in commit 0f3ba405 in an attempt
to fix 54805, but it didn't help. We didn't use signbit on some
platforms and instead defined it to x < 0.0f.

Reviewed-by: Kenneth Graunke <[email protected]>

4 files changed, 8 insertions, 15 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_clip_line.c b/src/mesa/drivers/dri/i965/brw_clip_line.c
index 90cd07cd4a3..3b8af58ec76 100644
--- a/src/mesa/drivers/dri/i965/brw_clip_line.c
+++ b/src/mesa/drivers/dri/i965/brw_clip_line.c
@@ -109,7 +109,7 @@ static void brw_clip_line_alloc_regs( struct brw_clip_compile *c )
  *        GLfloat dp0 = DOTPROD( vtx0, plane[p] );
  *        GLfloat dp1 = DOTPROD( vtx1, plane[p] );
  *
- *        if (IS_NEGATIVE(dp1)) {
+ *        if (dp1 < 0.0f) {
  *           GLfloat t = dp1 / (dp1 - dp0);
  *           if (t > t1) t1 = t;
  *        } else {
diff --git a/src/mesa/drivers/dri/i965/brw_clip_tri.c b/src/mesa/drivers/dri/i965/brw_clip_tri.c
index 62336fc795b..2227a65ae4c 100644
--- a/src/mesa/drivers/dri/i965/brw_clip_tri.c
+++ b/src/mesa/drivers/dri/i965/brw_clip_tri.c
@@ -320,7 +320,7 @@ void brw_clip_tri( struct brw_clip_compile *c )
 	    brw_MOV(p, get_addr_reg(vtx), deref_1uw(inlist_ptr, 0));
 
             load_clip_distance(c, vtxPrev, c->reg.dpPrev, hpos_offset, BRW_CONDITIONAL_L);
-	    /* IS_NEGATIVE(prev) */
+	    /* (prev < 0.0f) */
 	    brw_IF(p, BRW_EXECUTE_1);
 	    {
                load_clip_distance(c, vtx, c->reg.dp, hpos_offset, BRW_CONDITIONAL_GE);
@@ -366,7 +366,7 @@ void brw_clip_tri( struct brw_clip_compile *c )
 	       brw_ADD(p, c->reg.nr_verts, c->reg.nr_verts, brw_imm_ud(1));
 
                load_clip_distance(c, vtx, c->reg.dp, hpos_offset, BRW_CONDITIONAL_L);
-	       /* IS_NEGATIVE(next)
+	       /* (next < 0.0f)
 		*/
 	       brw_IF(p, BRW_EXECUTE_1);
 	       {
diff --git a/src/mesa/main/macros.h b/src/mesa/main/macros.h
index 712699f75a8..cd5f2d6f28b 100644
--- a/src/mesa/main/macros.h
+++ b/src/mesa/main/macros.h
@@ -799,13 +799,6 @@ NORMALIZE_3FV(GLfloat v[3])
 }
 
 
-/** Is float value negative? */
-static inline GLboolean
-IS_NEGATIVE(float x)
-{
-   return signbit(x) != 0;
-}
-
 /** Test two floats have opposite signs */
 static inline GLboolean
 DIFFERENT_SIGNS(GLfloat x, GLfloat y)
diff --git a/src/mesa/tnl/t_vb_cliptmp.h b/src/mesa/tnl/t_vb_cliptmp.h
index 83de16d76fb..7dafb83cf17 100644
--- a/src/mesa/tnl/t_vb_cliptmp.h
+++ b/src/mesa/tnl/t_vb_cliptmp.h
@@ -41,12 +41,12 @@ do {									\
 	 GLuint idx = inlist[i];					\
 	 GLfloat dp = CLIP_DOTPROD(idx, A, B, C, D );			\
 									\
-	 if (!IS_NEGATIVE(dpPrev)) {					\
+	 if (dpPrev >= 0.0f) {						\
 	    outlist[outcount++] = idxPrev;				\
 	 }								\
 									\
 	 if (DIFFERENT_SIGNS(dp, dpPrev)) {				\
-	    if (IS_NEGATIVE(dp)) {					\
+	    if (dp < 0.0f) {						\
 	       /* Going out of bounds.  Avoid division by zero as we	\
 		* know dp != dpPrev from DIFFERENT_SIGNS, above.	\
 		*/							\
@@ -85,15 +85,15 @@ do {									\
    if (mask & PLANE_BIT) {						\
       const GLfloat dp0 = CLIP_DOTPROD( v0, A, B, C, D );		\
       const GLfloat dp1 = CLIP_DOTPROD( v1, A, B, C, D );		\
-      const GLboolean neg_dp0 = IS_NEGATIVE(dp0);			\
-      const GLboolean neg_dp1 = IS_NEGATIVE(dp1);			\
+      const GLboolean neg_dp0 = dp0 < 0.0f;				\
+      const GLboolean neg_dp1 = dp1 < 0.0f;				\
       									\
       /* For regular clipping, we know from the clipmask that one	\
        * (or both) of these must be negative (otherwise we wouldn't	\
        * be here).							\
        * For userclip, there is only a single bit for all active	\
        * planes, so we can end up here when there is nothing to do,	\
-       * hence the second IS_NEGATIVE() test:				\
+       * hence the second < 0.0f test:					\
        */								\
       if (neg_dp0 && neg_dp1)						\
          return; /* both vertices outside clip plane: discard */	\