r300/compiler: disable register allocation for indexable temporaries in VS

If there is relative addressing of temporaries, we cannot change register
indices, so skip register allocation entirely. To utilize register allocation
at least partially, we need separate indexable and non-indexable register
files in both TGSI and Mesa IR.

src/mesa/drivers/dri/r300/compiler/r3xx_vertprog.c

 	struct temporary_allocation * ta;
 	unsigned int i, j;
 
-	compiler->code->num_temporaries = 0;
 	memset(hwtemps, 0, sizeof(hwtemps));
 
-	/* Pass 1: Count original temporaries and allocate structures */
+	/* Pass 1: Count original temporaries. */
 	for(inst = compiler->Base.Program.Instructions.Next; inst != &compiler->Base.Program.Instructions; inst = inst->Next) {
 		const struct rc_opcode_info * opcode = rc_get_opcode_info(inst->U.I.Opcode);
 
 			}
 		}
 	}
+	compiler->code->num_temporaries = num_orig_temps;
+
+	/* Pass 2: If there is relative addressing of temporaries, we cannot change register indices. Give up. */
+	for (inst = compiler->Base.Program.Instructions.Next; inst != &compiler->Base.Program.Instructions; inst = inst->Next) {
+		const struct rc_opcode_info *opcode = rc_get_opcode_info(inst->U.I.Opcode);
+
+		if (opcode->HasDstReg)
+			if (inst->U.I.DstReg.RelAddr)
+				return;
 
+		for (i = 0; i < opcode->NumSrcRegs; ++i) {
+			if (inst->U.I.SrcReg[i].File == RC_FILE_TEMPORARY &&
+			    inst->U.I.SrcReg[i].RelAddr) {
+				return;
+			}
+		}
+	}
+
+	compiler->code->num_temporaries = 0;
 	ta = (struct temporary_allocation*)memory_pool_malloc(&compiler->Base.Pool,
 			sizeof(struct temporary_allocation) * num_orig_temps);
 	memset(ta, 0, sizeof(struct temporary_allocation) * num_orig_temps);
 
-	/* Pass 2: Determine original temporary lifetimes */
+	/* Pass 3: Determine original temporary lifetimes */
 	for(inst = compiler->Base.Program.Instructions.Next; inst != &compiler->Base.Program.Instructions; inst = inst->Next) {
 		const struct rc_opcode_info * opcode = rc_get_opcode_info(inst->U.I.Opcode);
 		/* Instructions inside of loops need to use the ENDLOOP
 		}
 	}
 
-	/* Pass 3: Register allocation */
+	/* Pass 4: Register allocation */
 	for(inst = compiler->Base.Program.Instructions.Next; inst != &compiler->Base.Program.Instructions; inst = inst->Next) {
 		const struct rc_opcode_info * opcode = rc_get_opcode_info(inst->U.I.Opcode);
 
 
 	rc_dataflow_swizzles(&compiler->Base);
 
+	debug_program_log(compiler, "after dataflow");
+
 	allocate_temporary_registers(compiler);
 
-	debug_program_log(compiler, "after dataflow");
+	debug_program_log(compiler, "after register allocation");
+
 
 	translate_vertex_program(compiler);