From cecbe5d9c327af05a0fb36c7b05de39d26c067cf Mon Sep 17 00:00:00 2001
From: Jakub Jelinek <jakub@redhat.com>
Date: Tue, 26 Feb 2013 11:00:31 +0100
Subject: [PATCH] re PR tree-optimization/56448 (cc1 hangs on volatile array
with -O or above)
PR tree-optimization/56448
* fold-const.c (operand_equal_p) <case tcc_reference>: Don't look at
TREE_SIDE_EFFECTS if flags contain OEP_CONSTANT_ADDRESS_OF.
Clear OEP_CONSTANT_ADDRESS_OF from flags before recursing on second or
later operands of the references, or even first operand for
INDIRECT_REF, TARGET_MEM_REF or MEM_REF.
* gcc.c-torture/compile/pr56448.c: New test.
From-SVN: r196278
---
gcc/ChangeLog | 7 ++++
gcc/fold-const.c | 35 +++++++++++++------
gcc/testsuite/ChangeLog | 3 ++
gcc/testsuite/gcc.c-torture/compile/pr56448.c | 14 ++++++++
4 files changed, 48 insertions(+), 11 deletions(-)
create mode 100644 gcc/testsuite/gcc.c-torture/compile/pr56448.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 0fc1478c3dea..7b9b547b57a6 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,12 @@
2013-02-26 Jakub Jelinek <jakub@redhat.com>
+ PR tree-optimization/56448
+ * fold-const.c (operand_equal_p) <case tcc_reference>: Don't look at
+ TREE_SIDE_EFFECTS if flags contain OEP_CONSTANT_ADDRESS_OF.
+ Clear OEP_CONSTANT_ADDRESS_OF from flags before recursing on second or
+ later operands of the references, or even first operand for
+ INDIRECT_REF, TARGET_MEM_REF or MEM_REF.
+
PR tree-optimization/56443
* tree-vect-stmts.c (get_vectype_for_scalar_type_and_size): For
overaligned types, pass TYPE_UNSIGNED (scalar_type) as second argument
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 5acb4ad00594..26cfc0e83e43 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -2542,19 +2542,25 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
case tcc_reference:
/* If either of the pointer (or reference) expressions we are
- dereferencing contain a side effect, these cannot be equal. */
- if (TREE_SIDE_EFFECTS (arg0)
- || TREE_SIDE_EFFECTS (arg1))
+ dereferencing contain a side effect, these cannot be equal,
+ but their addresses can be. */
+ if ((flags & OEP_CONSTANT_ADDRESS_OF) == 0
+ && (TREE_SIDE_EFFECTS (arg0)
+ || TREE_SIDE_EFFECTS (arg1)))
return 0;
switch (TREE_CODE (arg0))
{
case INDIRECT_REF:
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
+ return OP_SAME (0);
+
case REALPART_EXPR:
case IMAGPART_EXPR:
return OP_SAME (0);
case TARGET_MEM_REF:
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
/* Require equal extra operands and then fall through to MEM_REF
handling of the two common operands. */
if (!OP_SAME_WITH_NULL (2)
@@ -2563,6 +2569,7 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
return 0;
/* Fallthru. */
case MEM_REF:
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
/* Require equal access sizes, and similar pointer types.
We can have incomplete types for array references of
variable-sized arrays from the Fortran frontent
@@ -2581,22 +2588,28 @@ operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags)
/* Operands 2 and 3 may be null.
Compare the array index by value if it is constant first as we
may have different types but same value here. */
- return (OP_SAME (0)
- && (tree_int_cst_equal (TREE_OPERAND (arg0, 1),
- TREE_OPERAND (arg1, 1))
- || OP_SAME (1))
+ if (!OP_SAME (0))
+ return 0;
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
+ return ((tree_int_cst_equal (TREE_OPERAND (arg0, 1),
+ TREE_OPERAND (arg1, 1))
+ || OP_SAME (1))
&& OP_SAME_WITH_NULL (2)
&& OP_SAME_WITH_NULL (3));
case COMPONENT_REF:
/* Handle operand 2 the same as for ARRAY_REF. Operand 0
may be NULL when we're called to compare MEM_EXPRs. */
- return OP_SAME_WITH_NULL (0)
- && OP_SAME (1)
- && OP_SAME_WITH_NULL (2);
+ if (!OP_SAME_WITH_NULL (0))
+ return 0;
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
+ return OP_SAME (1) && OP_SAME_WITH_NULL (2);
case BIT_FIELD_REF:
- return OP_SAME (0) && OP_SAME (1) && OP_SAME (2);
+ if (!OP_SAME (0))
+ return 0;
+ flags &= ~OEP_CONSTANT_ADDRESS_OF;
+ return OP_SAME (1) && OP_SAME (2);
default:
return 0;
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 8356fa46502a..1da7b6fe03a3 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
2013-02-26 Jakub Jelinek <jakub@redhat.com>
+ PR tree-optimization/56448
+ * gcc.c-torture/compile/pr56448.c: New test.
+
PR tree-optimization/56443
* gcc.dg/torture/pr56443.c: New test.
diff --git a/gcc/testsuite/gcc.c-torture/compile/pr56448.c b/gcc/testsuite/gcc.c-torture/compile/pr56448.c
new file mode 100644
index 000000000000..f10da6ce7526
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr56448.c
@@ -0,0 +1,14 @@
+/* PR tree-optimization/56448 */
+
+volatile int a[1];
+int b;
+
+void
+foo ()
+{
+ for (;;)
+ {
+ int *c[3][6] = { 0, 0, 0, &b, 0, 0, 0, 0, &b, 0, 0, 0, 0, 0, 0, 0, &b, (int *) &a[0] };
+ b = *c[2][5];
+ }
+}
--
GitLab