qbe

commit 3b708f506f5b5b45b5cc22493595a31e7183b620
parent 7d36a71a2287e28312403ab12a6ca5b49c7a73b0
Author: Quentin Carbonneaux <quentin.carbonneaux@yale.edu>
Date:   Thu, 20 Aug 2015 13:49:49 -0400

use loop frequency in ties of rpo

Diffstat:
M
lisc/ssa.c
 | 
16
+++++++++++-----

1 file changed, 11 insertions(+), 5 deletions(-)
diff --git a/lisc/ssa.c b/lisc/ssa.c
@@ -44,13 +44,19 @@ fillpreds(Fn *f)
 static int
 rporec(Blk *b, int x)
 {
-	if (b->id >= 0)
+	Blk *s1, *s2;
+
+	if (!b || b->id >= 0)
 		return x;
 	b->id = 1;
-	if (b->s2)
-		x = rporec(b->s2, x);
-	if (b->s1)
-		x = rporec(b->s1, x);
+	s1 = b->s1;
+	s2 = b->s2;
+	if (s1 && s2 && s1->loop > s2->loop) {
+		s1 = b->s2;
+		s2 = b->s1;
+	}
+	x = rporec(s1, x);
+	x = rporec(s2, x);
 	b->id = x;
 	assert(x >= 0);
 	return x - 1;