From: Eric Botcazou <ebotcazou@libertysurf.fr>
Date: Thu, 19 Dec 2002 20:27:56 +0000 (+0100)
Subject: re PR rtl-optimization/8988 (gcc3.2 and 3.2.1 with -O2 and -mcpu=i386 generates code... 
X-Git-Tag: releases/gcc-3.2.2~165
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=736c576bbae2bd2b1d26472a787b9e3bda0e63ef;p=thirdparty%2Fgcc.git

re PR rtl-optimization/8988 (gcc3.2 and 3.2.1 with -O2 and -mcpu=i386 generates code that segfaults)

	PR optimization/8988
	* loop.c (maybe_eliminate_biv): Kill REG_EQUAL notes mentioning
	the biv when eliminating.

From-SVN: r60329
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 49962b81341d..a088ccf3d212 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2002-12-19  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	PR optimization/8988
+	* loop.c (maybe_eliminate_biv): Kill REG_EQUAL notes mentioning
+	the biv when eliminating.
+
 2002-12-17  Jakub Jelinek  <jakub@redhat.com>
 
 	PR opt/8794
diff --git a/gcc/loop.c b/gcc/loop.c
index ff598d323c49..2dddc66e63ea 100644
--- a/gcc/loop.c
+++ b/gcc/loop.c
@@ -8521,11 +8521,12 @@ maybe_eliminate_biv (loop, bl, eliminate_p, threshold, insn_count)
       enum rtx_code code = GET_CODE (p);
       basic_block where_bb = 0;
       rtx where_insn = threshold >= insn_count ? 0 : p;
+      rtx note;
 
       /* If this is a libcall that sets a giv, skip ahead to its end.  */
       if (GET_RTX_CLASS (code) == 'i')
 	{
-	  rtx note = find_reg_note (p, REG_LIBCALL, NULL_RTX);
+	  note = find_reg_note (p, REG_LIBCALL, NULL_RTX);
 
 	  if (note)
 	    {
@@ -8543,6 +8544,8 @@ maybe_eliminate_biv (loop, bl, eliminate_p, threshold, insn_count)
 		}
 	    }
 	}
+
+      /* Closely examine the insn if the biv is mentioned.  */
       if ((code == INSN || code == JUMP_INSN || code == CALL_INSN)
 	  && reg_mentioned_p (reg, PATTERN (p))
 	  && ! maybe_eliminate_biv_1 (loop, PATTERN (p), p, bl,
@@ -8554,6 +8557,12 @@ maybe_eliminate_biv (loop, bl, eliminate_p, threshold, insn_count)
 		     bl->regno, INSN_UID (p));
 	  break;
 	}
+
+      /* If we are eliminating, kill REG_EQUAL notes mentioning the biv.  */
+      if (eliminate_p
+	  && (note = find_reg_note (p, REG_EQUAL, NULL_RTX)) != NULL_RTX
+	  && reg_mentioned_p (reg, XEXP (note, 0)))
+	remove_note (p, note);
     }
 
   if (p == loop->end)
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 735eb975d900..17e079d5e9b3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2002-12-19  Eric Botcazou  <ebotcazou@libertysurf.fr>
+
+	* gcc.c-torture/execute/20021219-1.c: New test.
+
 2002-12-18  Kriang Lerdsuwanakij  <lerdsuwa@users.sourceforge.net>
 
 	PR c++/8442
diff --git a/gcc/testsuite/gcc.c-torture/execute/20021219-1.c b/gcc/testsuite/gcc.c-torture/execute/20021219-1.c
new file mode 100644
index 000000000000..2e658a5a8859
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/20021219-1.c
@@ -0,0 +1,18 @@
+/* PR optimization/8988 */
+/* Contributed by Kevin Easton */
+
+void foo(char *p1, char **p2)
+{}
+ 
+int main(void)
+{
+  char str[] = "foo { xx }";
+  char *ptr = str + 5;
+
+  foo(ptr, &ptr);
+
+  while (*ptr && (*ptr == 13 || *ptr == 32))
+    ptr++;
+
+  return 0;
+}