Use INV_SQRT instead of 1/SQRTF

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/mesa/math/m_debug_norm.c

@@ -165,7 +165,7 @@ static void ref_norm_transform_normalize( const GLmatrix *mat,
 	    /* Hmmm, don't know how we could test the precalculated
 	     * length case...
 	     */
-            scale = 1.0 / SQRTF( len );
+            scale = INV_SQRTF( len );
 	    SCALE_SCALAR_3V( out[i], scale, t );
          } else {
             out[i][0] = out[i][1] = out[i][2] = 0;
@@ -241,7 +241,7 @@ static int test_norm_function( normal_func func, int mtype, long *cycles )
       ASSIGN_3V( d2[i], 0.0, 0.0, 0.0 );
       for ( j = 0 ; j < 3 ; j++ )
          s[i][j] = rnd();
-      length[i] = 1 / SQRTF( LEN_SQUARED_3FV( s[i] ) );
+      length[i] = INV_SQRTF( LEN_SQUARED_3FV( s[i] ) );
    }
 
    source->data = (GLfloat(*)[4]) s;

src/mesa/tnl/t_vb_points.c

@@ -64,7 +64,7 @@ run_point_stage(struct gl_context *ctx, struct tnl_pipeline_stage *stage)
       for (i = 0; i < VB->Count; i++) {
          const GLfloat dist = FABSF(*eyeCoord);
          const GLfloat q = p0 + dist * (p1 + dist * p2);
-         const GLfloat atten = (q != 0.0F) ? SQRTF(1.0F / q) : 1.0F;
+         const GLfloat atten = (q != 0.0F) ? INV_SQRTF(q) : 1.0F;
          size[i][0] = pointSize * atten; /* clamping done in rasterization */
          eyeCoord += eyeCoordStride;
       }