From 0c58cd9067b4718bd3bcaed635a511d286424138 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Thu, 19 Jul 2012 10:42:05 +0900
Subject: [PATCH] Generate only one daglabel for value operands.

As each value is now unique, their labels can also be unique, which will
improve CSE.
---
 tools/qfcc/include/expr.h |  1 +
 tools/qfcc/source/dags.c  | 14 +++++++++++---
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/tools/qfcc/include/expr.h b/tools/qfcc/include/expr.h
index 05e8b07c5..805af9784 100644
--- a/tools/qfcc/include/expr.h
+++ b/tools/qfcc/include/expr.h
@@ -158,6 +158,7 @@ typedef struct {
 
 typedef struct ex_value_s {
 	struct ex_value_s *next;
+	struct daglabel_s *daglabel;///< dag label for this value
 	etype_t     type;
 	union {
 		const char *string_val;			///< string constant
diff --git a/tools/qfcc/source/dags.c b/tools/qfcc/source/dags.c
index 1500bfc86..a078dc14c 100644
--- a/tools/qfcc/source/dags.c
+++ b/tools/qfcc/source/dags.c
@@ -89,6 +89,7 @@ operand_label (operand_t *op)
 {
 	operand_t  *o;
 	symbol_t   *sym = 0;
+	ex_value_t *val = 0;
 	daglabel_t *label;
 
 	if (!op)
@@ -108,11 +109,18 @@ operand_label (operand_t *op)
 		label = new_label ();
 		label->op = op;
 		sym->daglabel = label;
-	} else {
-		if (o->op_type != op_value && o->op_type != op_pointer)
-			debug (0, "unexpected operand type: %d", o->op_type);
+	} else if (o->op_type == op_value) {
+		val = o->o.value;
+		if (val->daglabel)
+			return val->daglabel;
 		label = new_label ();
 		label->op = op;
+		val->daglabel = label;
+	} else if (o->op_type == op_pointer) {
+		label = new_label ();
+		label->op = op;
+	} else {
+		internal_error (0, "unexpected operand type: %d", o->op_type);
 	}
 	return label;
 }