From: Marc Glisse <marc.glisse@inria.fr>
Date: Thu, 16 May 2013 10:26:51 +0000 (+0200)
Subject: re PR middle-end/57286 (infinite recursion in fold-const.c:10037)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=43bb4dd14d015211a19ccd8c1802cc7e1361d8b7;p=gcc.git

re PR middle-end/57286 (infinite recursion in fold-const.c:10037)

2013-05-16  Marc Glisse  <marc.glisse@inria.fr>

	PR middle-end/57286
gcc/
	* fold-const.c (fold_ternary_loc) <VEC_COND_EXPR>: Disable some
	transformations to avoid an infinite loop.

gcc/testsuite/
	* gcc.dg/pr57286.c: New testcase.
	* gcc.dg/vector-shift-2.c: Don't assume int has size 4.
	* g++.dg/ext/vector22.C: Comment out transformations not
	performed anymore.

From-SVN: r198964
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a54dceca35c..3a0929cd122 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2013-05-16  Marc Glisse  <marc.glisse@inria.fr>
+
+	PR middle-end/57286
+	* fold-const.c (fold_ternary_loc) <VEC_COND_EXPR>: Disable some
+	transformations to avoid an infinite loop.
+
 2013-05-16  Marek Polacek  <polacek@redhat.com>
 
 	* tree-scalar-evolution.c (scev_const_prop): Add more dumps.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index e02f0c60d9a..97b5216eb71 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -14211,6 +14211,12 @@ fold_ternary_loc (location_t loc, enum tree_code code, tree type,
 				    fold_convert_loc (loc, type,
 						      TREE_OPERAND (arg0, 0)));
 
+      /* Disable the transformations below for vectors, since
+	 fold_binary_op_with_conditional_arg may undo them immediately,
+	 yielding an infinite loop.  */
+      if (code == VEC_COND_EXPR)
+	return NULL_TREE;
+
       /* Convert A ? B : 0 into A && B if A and B are truth values.  */
       if (integer_zerop (op2)
 	  && truth_value_p (TREE_CODE (arg0))
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e608612d2d1..6ec937c4ad5 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,11 @@
+2013-05-16  Marc Glisse  <marc.glisse@inria.fr>
+
+	PR middle-end/57286
+	* gcc.dg/pr57286.c: New testcase.
+	* gcc.dg/vector-shift-2.c: Don't assume int has size 4.
+	* g++.dg/ext/vector22.C: Comment out transformations not
+	performed anymore.
+
 2013-05-15  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	PR target/57260
diff --git a/gcc/testsuite/g++.dg/ext/vector22.C b/gcc/testsuite/g++.dg/ext/vector22.C
index ab569c7dffa..47f64e7e7a7 100644
--- a/gcc/testsuite/g++.dg/ext/vector22.C
+++ b/gcc/testsuite/g++.dg/ext/vector22.C
@@ -3,13 +3,15 @@
 
 typedef unsigned vec __attribute__((vector_size(4*sizeof(int))));
 
+/* Disabled after PR57286
 void f(vec*a,vec*b){
   *a=(*a)?-1:(*b<10);
   *b=(*b)?(*a<10):0;
 }
+*/
 void g(vec*a,vec*b){
   *a=(*a)?(*a<*a):-1;
-  *b=(*b)?-1:(*b<*b);
+// *b=(*b)?-1:(*b<*b);
 }
 void h(vec*a){
   *a=(~*a==5);
diff --git a/gcc/testsuite/gcc.dg/pr57286.c b/gcc/testsuite/gcc.dg/pr57286.c
new file mode 100644
index 00000000000..c6f45305487
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr57286.c
@@ -0,0 +1,7 @@
+/* { dg-do compile } */
+/* { dg-options "-O" } */
+
+typedef int vec __attribute__ ((vector_size (4*sizeof(int))));
+void f (vec *x){
+    *x = (*x < 0) | 1;
+}
diff --git a/gcc/testsuite/gcc.dg/vector-shift-2.c b/gcc/testsuite/gcc.dg/vector-shift-2.c
index 14fff121c5e..380f2dfb307 100644
--- a/gcc/testsuite/gcc.dg/vector-shift-2.c
+++ b/gcc/testsuite/gcc.dg/vector-shift-2.c
@@ -1,7 +1,7 @@
 /* { dg-do compile } */
 /* { dg-options "-O -fdump-tree-ccp1" } */
 
-typedef unsigned vec __attribute__ ((vector_size (16)));
+typedef unsigned vec __attribute__ ((vector_size (4*sizeof(int))));
 void
 f (vec *a)
 {