Mesa (gallium-0.1): tgsi: Rewrite NRM opcode, store 1.0 in W component.

[Jose Fonseca]

Module: Mesa
Branch: gallium-0.1
Commit: da54d3999a32deb52a5d3d1b4a8a6030fb5e536d
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=da54d3999a32deb52a5d3d1b4a8a6030fb5e536d

Author: Michal Krol <michal at vmware.com>
Date:   Thu Mar 12 11:54:11 2009 +0100

tgsi: Rewrite NRM opcode, store 1.0 in W component.

---

 src/gallium/auxiliary/tgsi/tgsi_exec.c |   50 +++++++++++++++++--------------
 1 files changed, 27 insertions(+), 23 deletions(-)

diff --git a/src/gallium/auxiliary/tgsi/tgsi_exec.c b/src/gallium/auxiliary/tgsi/tgsi_exec.c
index 7cdf683..d2d4cf7 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_exec.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_exec.c
@@ -2612,31 +2612,35 @@ exec_instruction(
 
    case TGSI_OPCODE_NRM:
       /* 3-component vector normalize */
-      {
-         union tgsi_exec_channel tmp, dot;
-
-         /* tmp = dp3(src0, src0): */
-         FETCH( &r[0], 0, CHAN_X );
-         micro_mul( &tmp, &r[0], &r[0] );
-
-         FETCH( &r[1], 0, CHAN_Y );
-         micro_mul( &dot, &r[1], &r[1] );
-         micro_add( &tmp, &tmp, &dot );
-
-         FETCH( &r[2], 0, CHAN_Z );
-         micro_mul( &dot, &r[2], &r[2] );
-         micro_add( &tmp, &tmp, &dot );
-
-         /* tmp = 1 / sqrt(tmp) */
-         micro_sqrt( &tmp, &tmp );
-         micro_div( &tmp, &mach->Temps[TEMP_1_I].xyzw[TEMP_1_C], &tmp );
+      if(IS_CHANNEL_ENABLED(*inst, CHAN_X) ||
+         IS_CHANNEL_ENABLED(*inst, CHAN_Y) ||
+         IS_CHANNEL_ENABLED(*inst, CHAN_Z)) {
+         /* r3 = sqrt(dp3(src0, src0)) */
+         FETCH(&r[0], 0, CHAN_X);
+         micro_mul(&r[3], &r[0], &r[0]);
+         FETCH(&r[1], 0, CHAN_Y);
+         micro_mul(&r[4], &r[1], &r[1]);
+         micro_add(&r[3], &r[3], &r[4]);
+         FETCH(&r[2], 0, CHAN_Z);
+         micro_mul(&r[4], &r[2], &r[2]);
+         micro_add(&r[3], &r[3], &r[4]);
+         micro_sqrt(&r[3], &r[3]);
 
-         /* note: w channel is undefined */
-         FOR_EACH_ENABLED_CHANNEL( *inst, chan_index ) {
-            /* chan = chan * tmp */
-            micro_mul( &r[chan_index], &tmp, &r[chan_index] );
-            STORE( &r[chan_index], 0, chan_index );
+         if (IS_CHANNEL_ENABLED(*inst, CHAN_X)) {
+            micro_div(&r[0], &r[0], &r[3]);
+            STORE(&r[0], 0, CHAN_X);
          }
+         if (IS_CHANNEL_ENABLED(*inst, CHAN_Y)) {
+            micro_div(&r[1], &r[1], &r[3]);
+            STORE(&r[1], 0, CHAN_Y);
+         }
+         if (IS_CHANNEL_ENABLED(*inst, CHAN_Z)) {
+            micro_div(&r[2], &r[2], &r[3]);
+            STORE(&r[2], 0, CHAN_Z);
+         }
+      }
+      if (IS_CHANNEL_ENABLED(*inst, CHAN_W)) {
+         STORE(&mach->Temps[TEMP_1_I].xyzw[TEMP_1_C], 0, CHAN_W);
       }
       break;