From f84a2ecae8cdd8a7e449347c81c72643ecf732ed Mon Sep 17 00:00:00 2001
From: Chris Hanson <org/chris-hanson/cph>
Date: Wed, 26 Apr 1989 05:09:52 +0000
Subject: [PATCH] Add new phase to find pairs of invertible RTL expressions and
 eliminate them.

---
 v7/src/compiler/base/toplev.scm | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/v7/src/compiler/base/toplev.scm b/v7/src/compiler/base/toplev.scm
index d6ae1bf54..8df151911 100644
--- a/v7/src/compiler/base/toplev.scm
+++ b/v7/src/compiler/base/toplev.scm
@@ -1,6 +1,6 @@
 #| -*-Scheme-*-
 
-$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/compiler/base/toplev.scm,v 4.15 1989/04/21 17:06:51 markf Exp $
+$Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/compiler/base/toplev.scm,v 4.16 1989/04/26 05:09:52 cph Exp $
 
 Copyright (c) 1988 Massachusetts Institute of Technology
 
@@ -606,6 +606,7 @@ MIT in each case. |#
     (lambda ()
       (if compiler:cse?
 	  (phase/common-subexpression-elimination))
+      (phase/invertible-expression-elimination)
       (phase/lifetime-analysis)
       (if compiler:code-compression?
 	  (phase/code-compression))
@@ -617,6 +618,11 @@ MIT in each case. |#
   (compiler-subphase "Common Subexpression Elimination"
     (lambda ()
       (common-subexpression-elimination *rtl-graphs*))))
+
+(define (phase/invertible-expression-elimination)
+  (compiler-subphase "Invertible Expression Elimination"
+    (lambda ()
+      (invertible-expression-elimination *rtl-graphs*))))
 (define (phase/lifetime-analysis)
   (compiler-subphase "Lifetime Analysis"
     (lambda ()
-- 
2.25.1