Fix CSE RTL sharing ICE (PR rtl-optimization/55010)

Submitted by Jakub Jelinek on Oct. 22, 2012, 7:23 p.m.

Details

Message ID 20121022192331.GE1752@tucnak.redhat.com
State New
Headers show

Commit Message

Jakub Jelinek Oct. 22, 2012, 7:23 p.m.
Hi!

On the following testcase we have IF_THEN_ELSE in insn notes,
and when folding it, folded_arg1 is a subreg from earlier CC setter,
as the other argument has equiv constant, simplify_relational_operation
is called on it to simplify it and we end up with invalid RTL sharing
of the subreg in between the CC setter insn and the insn with the REG_EQ*
note.

Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?

2012-10-22  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/55010
	* cse.c (fold_rtx): Call copy_rtx on folded_arg{0,1} before passing
	it to simplify_relational_operation.

	* gcc.dg/pr55010.c: New test.


	Jakub

Comments

Eric Botcazou Oct. 24, 2012, 8:42 a.m.
> On the following testcase we have IF_THEN_ELSE in insn notes,
> and when folding it, folded_arg1 is a subreg from earlier CC setter,
> as the other argument has equiv constant, simplify_relational_operation
> is called on it to simplify it and we end up with invalid RTL sharing
> of the subreg in between the CC setter insn and the insn with the REG_EQ*
> note.
> 
> Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
> trunk?
> 
> 2012-10-22  Jakub Jelinek  <jakub@redhat.com>
> 
> 	PR rtl-optimization/55010
> 	* cse.c (fold_rtx): Call copy_rtx on folded_arg{0,1} before passing
> 	it to simplify_relational_operation.

OK with:

	* cse.c (fold_rtx) <RTX_COMPARE>: Call copy_rtx on ...

and if you also fix the long simplify_relational_operation line.

Patch hide | download patch | download mbox

--- gcc/cse.c.jj	2012-10-16 13:15:45.000000000 +0200
+++ gcc/cse.c	2012-10-22 10:44:34.100033945 +0200
@@ -3461,8 +3461,8 @@  fold_rtx (rtx x, rtx insn)
 	}
 
       {
-	rtx op0 = const_arg0 ? const_arg0 : folded_arg0;
-	rtx op1 = const_arg1 ? const_arg1 : folded_arg1;
+	rtx op0 = const_arg0 ? const_arg0 : copy_rtx (folded_arg0);
+	rtx op1 = const_arg1 ? const_arg1 : copy_rtx (folded_arg1);
         new_rtx = simplify_relational_operation (code, mode, mode_arg0, op0, op1);
       }
       break;
--- gcc/testsuite/gcc.dg/pr55010.c.jj	2012-10-22 10:47:47.289857369 +0200
+++ gcc/testsuite/gcc.dg/pr55010.c	2012-10-22 10:47:33.000000000 +0200
@@ -0,0 +1,13 @@ 
+/* PR rtl-optimization/55010 */
+/* { dg-do compile } */
+/* { dg-options "-O2" } */
+/* { dg-additional-options "-march=i686" { target { { i?86-*-* x86_64-*-* } && ia32 } } } */
+
+long long int a;
+unsigned long long int b;
+
+void
+foo (void)
+{
+  a = (a < 0) / ((a -= b) ? b >= ((b = a) || 0) : 0);
+}