r300/compiler: use perspective division only for TXP in shadow samplers

diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c b/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c
index e1bb7c72131aafaff3401b8aa8665967712975ac..f7c54d0fe8110454ad2bb01f7dfbe3f063788b41 100644 (file)
--- a/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c
+++ b/src/mesa/drivers/dri/r300/compiler/radeon_program_tex.c
@@ -113,13 +113,13 @@ int radeonTransformTEX(
                        return 1;
                } else {
                        rc_compare_func comparefunc = compiler->state.unit[inst->U.I.TexSrcUnit].texture_compare_func;
-                       struct rc_instruction * inst_rcp = rc_insert_new_instruction(c, inst);
-                       struct rc_instruction * inst_mad = rc_insert_new_instruction(c, inst_rcp);
-                       struct rc_instruction * inst_cmp = rc_insert_new_instruction(c, inst_mad);
-                       unsigned tmp_recip_w = rc_find_free_temporary(c);
+                       struct rc_instruction * inst_rcp = NULL;
+                       struct rc_instruction * inst_mad;
+                       struct rc_instruction * inst_cmp;
                        unsigned tmp_texsample = rc_find_free_temporary(c);
                        unsigned tmp_sum = rc_find_free_temporary(c);
-                       int pass, fail;
+                       unsigned tmp_recip_w;
+                       int pass, fail, tex;
 
                        /* Save the output register. */
                        struct rc_dst_register output_reg = inst->U.I.DstReg;
@@ -129,28 +129,40 @@ int radeonTransformTEX(
                        inst->U.I.DstReg.Index = tmp_texsample;
                        inst->U.I.DstReg.WriteMask = RC_MASK_XYZW;
 
-                       /* Compute 1/W. */
-                       inst_rcp->U.I.Opcode = RC_OPCODE_RCP;
-                       inst_rcp->U.I.DstReg.File = RC_FILE_TEMPORARY;
-                       inst_rcp->U.I.DstReg.Index = tmp_recip_w;
-                       inst_rcp->U.I.DstReg.WriteMask = RC_MASK_W;
-                       inst_rcp->U.I.SrcReg[0] = inst->U.I.SrcReg[0];
-                       inst_rcp->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_WWWW;
+                       if (inst->U.I.Opcode == RC_OPCODE_TXP) {
+                               tmp_recip_w = rc_find_free_temporary(c);
+
+                               /* Compute 1/W. */
+                               inst_rcp = rc_insert_new_instruction(c, inst);
+                               inst_rcp->U.I.Opcode = RC_OPCODE_RCP;
+                               inst_rcp->U.I.DstReg.File = RC_FILE_TEMPORARY;
+                               inst_rcp->U.I.DstReg.Index = tmp_recip_w;
+                               inst_rcp->U.I.DstReg.WriteMask = RC_MASK_W;
+                               inst_rcp->U.I.SrcReg[0] = inst->U.I.SrcReg[0];
+                               inst_rcp->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_WWWW;
+                       }
 
-                       /* Perspective-divide r (=depth) by W and add the texture sample (see below). */
-                       inst_mad->U.I.Opcode = RC_OPCODE_MAD;
+                       /* Perspective-divide r by W (if it's TXP) and add the texture sample (see below). */
+                       inst_mad = rc_insert_new_instruction(c, inst_rcp ? inst_rcp : inst);
                        inst_mad->U.I.DstReg.File = RC_FILE_TEMPORARY;
                        inst_mad->U.I.DstReg.Index = tmp_sum;
                        inst_mad->U.I.SrcReg[0] = inst->U.I.SrcReg[0];
                        inst_mad->U.I.SrcReg[0].Swizzle = RC_SWIZZLE_ZZZZ;
-                       inst_mad->U.I.SrcReg[1].File = RC_FILE_TEMPORARY;
-                       inst_mad->U.I.SrcReg[1].Index = tmp_recip_w;
-                       inst_mad->U.I.SrcReg[1].Swizzle = RC_SWIZZLE_WWWW;
-                       inst_mad->U.I.SrcReg[2].File = RC_FILE_TEMPORARY;
-                       inst_mad->U.I.SrcReg[2].Index = tmp_texsample;
-                       inst_mad->U.I.SrcReg[2].Swizzle = compiler->state.unit[inst->U.I.TexSrcUnit].depth_texture_swizzle;
-
-                       /* Recall that SrcReg[0] is tex, SrcReg[2] is r and:
+                       if (inst->U.I.Opcode == RC_OPCODE_TXP) {
+                               inst_mad->U.I.Opcode = RC_OPCODE_MAD;
+                               inst_mad->U.I.SrcReg[1].File = RC_FILE_TEMPORARY;
+                               inst_mad->U.I.SrcReg[1].Index = tmp_recip_w;
+                               inst_mad->U.I.SrcReg[1].Swizzle = RC_SWIZZLE_WWWW;
+                               tex = 2;
+                       } else {
+                               inst_mad->U.I.Opcode = RC_OPCODE_ADD;
+                               tex = 1;
+                       }
+                       inst_mad->U.I.SrcReg[tex].File = RC_FILE_TEMPORARY;
+                       inst_mad->U.I.SrcReg[tex].Index = tmp_texsample;
+                       inst_mad->U.I.SrcReg[tex].Swizzle = compiler->state.unit[inst->U.I.TexSrcUnit].depth_texture_swizzle;
+
+                       /* Recall that SrcReg[0] is r, SrcReg[tex] is tex and:
                         *   LESS:    r  < tex  <=>      -tex+r < 0
                         *   GEQUAL:  r >= tex  <=> not (-tex+r < 0)
                         *   GREATER: r  > tex  <=>       tex-r < 0
@@ -158,7 +170,7 @@ int radeonTransformTEX(
                         *
                         * This negates either r or tex: */
                        if (comparefunc == RC_COMPARE_FUNC_LESS || comparefunc == RC_COMPARE_FUNC_GEQUAL)
-                               inst_mad->U.I.SrcReg[2].Negate = inst_mad->U.I.SrcReg[2].Negate ^ RC_MASK_XYZW;
+                               inst_mad->U.I.SrcReg[tex].Negate = inst_mad->U.I.SrcReg[tex].Negate ^ RC_MASK_XYZW;
                        else
                                inst_mad->U.I.SrcReg[0].Negate = inst_mad->U.I.SrcReg[0].Negate ^ RC_MASK_XYZW;
 
@@ -171,6 +183,7 @@ int radeonTransformTEX(
                                fail = 1;
                        }
 
+                       inst_cmp = rc_insert_new_instruction(c, inst_mad);
                        inst_cmp->U.I.Opcode = RC_OPCODE_CMP;
                        inst_cmp->U.I.DstReg = output_reg;
                        inst_cmp->U.I.SrcReg[0].File = RC_FILE_TEMPORARY;