From: Richard Henderson <rth@redhat.com>
Date: Thu, 26 Oct 2000 00:17:53 +0000 (-0700)
Subject: cse.c (find_comparison_args): Check that we can reverse a comparison if needed before... 
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=78192b0984feaab04d373d0754d06d8a7cd623f3;p=gcc.git

cse.c (find_comparison_args): Check that we can reverse a comparison if needed before accepting the substitution.

        * cse.c (find_comparison_args): Check that we can reverse a
        comparison if needed before accepting the substitution.

From-SVN: r37064
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 03aa3176d48..3edb9b2bff5 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2000-10-25  Richard Henderson  <rth@redhat.com>
+
+	* cse.c (find_comparison_args): Check that we can reverse a
+	comparison if needed before accepting the substitution.
+
 2000-10-25  Richard Henderson  <rth@redhat.com>
 
 	* reload.c (find_reloads_address_part): Kill rtx obstack hackery.
diff --git a/gcc/cse.c b/gcc/cse.c
index ac9ae6be46c..17d35ceff76 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -3234,6 +3234,12 @@ find_comparison_args (code, parg1, parg2, pmode1, pmode2)
       if (x == 0)
 	break;
 
+      /* If we need to reverse the comparison, make sure that that is
+	 possible -- we can't necessarily infer the value of GE from LT
+	 with floating-point operands.  */
+      if (reverse_code && ! can_reverse_comparison_p (x, NULL_RTX))
+	break;
+
       arg1 = XEXP (x, 0), arg2 = XEXP (x, 1);
       if (GET_RTX_CLASS (GET_CODE (x)) == '<')
 	code = GET_CODE (x);