From: Roger Sayle <roger@eyesopen.com>
Date: Mon, 20 Dec 2004 02:43:14 +0000 (+0000)
Subject: re PR middle-end/19068 ([3.3 only] Wrong code for MIN_EXPR and MAX_EXPR)
X-Git-Tag: releases/gcc-3.3.6~171
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8d79b7b686d8b4f4da3235e26f238800ddcac6aa;p=thirdparty%2Fgcc.git

re PR middle-end/19068 ([3.3 only] Wrong code for MIN_EXPR and MAX_EXPR)


	PR middle-end/19068
	* expr.c (expand_expr_real_1) <MAX_EXPR>: Ensure that target, op0
	and op1 are all registers (or constants) before expanding the RTL
	comparison sequence [to avoid reg_overlap_mentioned (target, op1)].

	* g++.dg/opt/max1.C: New test case.

From-SVN: r92404
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 8151e64a93c0..28cbd426ba61 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2004-12-19  Roger Sayle  <roger@eyesopen.com>
+
+	PR middle-end/19068
+	* expr.c (expand_expr_real_1) <MAX_EXPR>: Ensure that target, op0
+	and op1 are all registers (or constants) before expanding the RTL
+	comparison sequence [to avoid reg_overlap_mentioned (target, op1)].
+
 2004-12-16  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR middle-end/18882
diff --git a/gcc/expr.c b/gcc/expr.c
index a2b0c8305687..78b35db8c847 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -8462,9 +8462,14 @@ expand_expr (exp, target, tmode, modifier)
       /* At this point, a MEM target is no longer useful; we will get better
 	 code without it.  */
 
-      if (GET_CODE (target) == MEM)
+      if (! REG_P (target))
 	target = gen_reg_rtx (mode);
 
+      /* We generate better code and avoid problems with op1 mentioning
+	 target by forcing op1 into a pseudo if it isn't a constant.  */
+      if (! CONSTANT_P (op1))
+	op1 = force_reg (mode, op1);
+
       if (target != op0)
 	emit_move_insn (target, op0);
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e1d6b270823c..383a8e6082a4 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2004-12-19  Roger Sayle  <roger@eyesopen.com>
+
+	PR middle-end/19068
+	* g++.dg/opt/max1.C: New test case.
+
 2004-12-16  Wolfgang Bangerth  <bangerth@dealii.com>
 
 	* g++.dg/other/complex1.C: New test.