t_vp_build: fix temporary register allocation to minimise the allocations

diff --git a/src/mesa/tnl/t_vp_build.c b/src/mesa/tnl/t_vp_build.c
index b7bc1977237dd0eb6577f5b555d6e552e2523058..a7fd815a2602e47c44f2026ce31aba4af4d43aca 100644 (file)
--- a/src/mesa/tnl/t_vp_build.c
+++ b/src/mesa/tnl/t_vp_build.c
@@ -890,7 +890,6 @@ static void build_lighting( struct tnl_program *p )
    {
       struct ureg shininess = get_material(p, 0, STATE_SHININESS);
       emit_op1(p, OPCODE_MOV, dots,  WRITEMASK_W, swizzle1(shininess,X));
-      release_temp(p, shininess);
 
       _col0 = make_temp(p, get_scenecolor(p, 0));
       if (separate)
@@ -904,7 +903,6 @@ static void build_lighting( struct tnl_program *p )
       struct ureg shininess = get_material(p, 1, STATE_SHININESS);
       emit_op1(p, OPCODE_MOV, dots, WRITEMASK_Z, 
               negate(swizzle1(shininess,X)));
-      release_temp(p, shininess);
 
       _bfc0 = make_temp(p, get_scenecolor(p, 1));
       if (separate)
@@ -972,7 +970,6 @@ static void build_lighting( struct tnl_program *p )
            struct ureg tmpPpli = get_temp(p);
 
            VPpli = get_temp(p); 
-           half = get_temp(p);
  
             /* In homogeneous object coordinates
              */
@@ -983,6 +980,9 @@ static void build_lighting( struct tnl_program *p )
             */
            emit_op2(p, OPCODE_SUB, VPpli, 0, tmpPpli, V); 
 
+            /* we're done with tmpPpli now */
+           release_temp(p, tmpPpli);
+
            /* Normalize VPpli.  The dist value also used in
             * attenuation below.
             */
@@ -997,10 +997,14 @@ static void build_lighting( struct tnl_program *p )
                p->state->unit[i].light_attenuated) {
               att = calculate_light_attenuation(p, i, VPpli, dist);
            }
+           
+           /* We're done with dist now */
+           release_temp(p, dist);
         
       
            /* Calculate viewer direction, or use infinite viewer:
             */
+           half = get_temp(p);
            if (p->state->light_local_viewer) {
               struct ureg eye_hat = get_eye_position_normalized(p);
               emit_op2(p, OPCODE_SUB, half, 0, VPpli, eye_hat);
@@ -1011,9 +1015,6 @@ static void build_lighting( struct tnl_program *p )
            }
 
            emit_normalize_vec3(p, half, half);
-
-           release_temp(p, dist);
-           release_temp(p, tmpPpli);
         }
 
         /* Calculate dot products:
@@ -1021,6 +1022,10 @@ static void build_lighting( struct tnl_program *p )
         emit_op2(p, OPCODE_DP3, dots, WRITEMASK_X, normal, VPpli);
         emit_op2(p, OPCODE_DP3, dots, WRITEMASK_Y, normal, half);
 
+        /* we're done with VPpli and half now, so free them as to not drive up
+           our temp usage unnecessary */
+        release_temp(p, VPpli);
+        release_temp(p, half);
        
         /* Front face lighting:
          */
@@ -1109,8 +1114,6 @@ static void build_lighting( struct tnl_program *p )
            release_temp(p, specular);
         }
 
-        release_temp(p, half);
-        release_temp(p, VPpli);
         release_temp(p, att);
       }
    }