Mesa (master): r600: set barrier for tex inst if dst is used earlier, might overwrite it otherwise

[Alex Deucher]

Module: Mesa
Branch: master
Commit: 869e20bcb7db9c6540eb6b538104303df738d302
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=869e20bcb7db9c6540eb6b538104303df738d302

Author: Andre Maasikas <amaasikas at gmail.com>
Date:   Wed Oct 21 19:04:21 2009 +0300

r600: set barrier for tex inst if dst is used earlier, might overwrite it otherwise

---

 src/mesa/drivers/dri/r600/r700_fragprog.c |   27 +++++++++++++++++++++++++--
 1 files changed, 25 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/r600/r700_fragprog.c b/src/mesa/drivers/dri/r600/r700_fragprog.c
index 3736bce..0f549ea 100644
--- a/src/mesa/drivers/dri/r600/r700_fragprog.c
+++ b/src/mesa/drivers/dri/r600/r700_fragprog.c
@@ -135,15 +135,19 @@ GLboolean Find_Instruction_Dependencies_fp(struct r700_fragment_program *fp,
 {
     GLuint i, j;
     GLint * puiTEMPwrites;
+    GLint * puiTEMPreads;
     struct prog_instruction * pILInst;
     InstDeps         *pInstDeps;
     struct prog_instruction * texcoord_DepInst;
     GLint              nDepInstID;
 
     puiTEMPwrites = (GLint*) MALLOC(sizeof(GLuint)*mesa_fp->Base.NumTemporaries);
+    puiTEMPreads = (GLint*) MALLOC(sizeof(GLuint)*mesa_fp->Base.NumTemporaries);
+
     for(i=0; i<mesa_fp->Base.NumTemporaries; i++)
     {
         puiTEMPwrites[i] = -1;
+        puiTEMPreads[i] = -1;
     }
 
     pInstDeps = (InstDeps*)MALLOC(sizeof(InstDeps)*mesa_fp->Base.NumInstructions);
@@ -167,6 +171,11 @@ GLboolean Find_Instruction_Dependencies_fp(struct r700_fragment_program *fp,
             {
                 //Set dep.
                 pInstDeps[i].nSrcDeps[j] = puiTEMPwrites[pILInst->SrcReg[j].Index];
+                //Set first read
+                if(puiTEMPreads[pILInst->SrcReg[j].Index] < 0 )
+                {
+                    puiTEMPreads[pILInst->SrcReg[j].Index] = i;
+                }
             }
             else
             {
@@ -177,8 +186,6 @@ GLboolean Find_Instruction_Dependencies_fp(struct r700_fragment_program *fp,
 
     fp->r700AsmCode.pInstDeps = pInstDeps;
 
-    FREE(puiTEMPwrites);
-
     //Find dep for tex inst    
     for(i=0; i<mesa_fp->Base.NumInstructions; i++)
     {
@@ -203,9 +210,25 @@ GLboolean Find_Instruction_Dependencies_fp(struct r700_fragment_program *fp,
                 {   //... other deps?
                 }
             }
+            // make sure that we dont overwrite src used earlier
+            nDepInstID = puiTEMPreads[pILInst->DstReg.Index];
+            if(nDepInstID < i)
+            {
+                pInstDeps[i].nDstDep = puiTEMPreads[pILInst->DstReg.Index];
+                texcoord_DepInst = &(mesa_fp->Base.Instructions[nDepInstID]);
+                if(GL_TRUE == IsAlu(texcoord_DepInst->Opcode) )
+                {
+                    pInstDeps[nDepInstID].nDstDep = i;
+                }
+ 
+            }
+
         }
 	}
 
+    FREE(puiTEMPwrites);
+    FREE(puiTEMPreads);
+
     return GL_TRUE;
 }