r300/compiler: Handle loops in the register allocator.

diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_pair_regalloc.c b/src/mesa/drivers/dri/r300/compiler/radeon_pair_regalloc.c
index 8a912da461302f8da66753e58ff502b221d9a578..ce72cd97ab2115c2582a1b2d7a929ba4b92f57d7 100644 (file)
--- a/src/mesa/drivers/dri/r300/compiler/radeon_pair_regalloc.c
+++ b/src/mesa/drivers/dri/r300/compiler/radeon_pair_regalloc.c
@@ -65,6 +65,11 @@ struct regalloc_state {
 
        struct hardware_register * HwTemporary;
        unsigned int NumHwTemporaries;
+       /**
+        * If an instruction is inside of a loop, end_loop will be the
+        * IP of the ENDLOOP instruction, otherwise end_loop will be 0
+        */
+       int end_loop;
 };
 
 static void print_live_intervals(struct live_intervals * src)
@@ -178,10 +183,10 @@ static void scan_callback(void * data, struct rc_instruction * inst,
                else
                        reg->Live.Start = inst->IP;
                reg->Live.End = inst->IP;
-       } else {
-               if (inst->IP > reg->Live.End)
-                       reg->Live.End = inst->IP;
-       }
+       } else if (s->end_loop)
+               reg->Live.End = s->end_loop;
+       else if (inst->IP > reg->Live.End)
+               reg->Live.End = inst->IP;
 }
 
 static void compute_live_intervals(struct regalloc_state * s)
@@ -191,6 +196,31 @@ static void compute_live_intervals(struct regalloc_state * s)
        for(struct rc_instruction * inst = s->C->Program.Instructions.Next;
            inst != &s->C->Program.Instructions;
            inst = inst->Next) {
+
+               /* For all instructions inside of a loop, the ENDLOOP
+                * instruction is used as the end of the live interval. */
+               if (inst->U.I.Opcode == RC_OPCODE_BGNLOOP && !s->end_loop) {
+                       int loops = 1;
+                       struct rc_instruction * tmp;
+                       for(tmp = inst->Next;
+                                       tmp != &s->C->Program.Instructions;
+                                       tmp = tmp->Next) {
+                               if (tmp->U.I.Opcode == RC_OPCODE_BGNLOOP) {
+                                       loops++;
+                                       break;
+                               } else if (tmp->U.I.Opcode
+                                                       == RC_OPCODE_ENDLOOP) {
+                                       if(!--loops) {
+                                               s->end_loop = tmp->IP;
+                                               break;
+                                       }
+                               }
+                       }
+               }
+
+               if (inst->IP == s->end_loop)
+                       s->end_loop = 0;
+
                rc_for_all_reads_mask(inst, scan_callback, s);
                rc_for_all_writes_mask(inst, scan_callback, s);
        }