re PR middle-end/42512 (integer wrong code bug with loop)

2010-01-09  Richard Guenther  <rguenther@suse.de>

	PR middle-end/42512
	* tree-scalar-evolution.c (interpret_loop_phi): Make sure
	the evolution is compatible with the initial condition.

	* gcc.c-torture/execute/pr42512.c: New testcase.

From-SVN: r155757
This commit is contained in:
Richard Guenther 2010-01-09 12:04:17 +00:00 committed by Richard Biener
parent 0462fd5e01
commit 73c865fab7
4 changed files with 41 additions and 0 deletions

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@ -1,3 +1,9 @@
2010-01-09 Richard Guenther <rguenther@suse.de>
PR middle-end/42512
* tree-scalar-evolution.c (interpret_loop_phi): Make sure
the evolution is compatible with the initial condition.
2010-01-09 Jakub Jelinek <jakub@redhat.com>
* gcc.c (process_command): Update copyright notice dates.

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@ -1,3 +1,8 @@
2010-01-09 Richard Guenther <rguenther@suse.de>
PR middle-end/42512
* gcc.c-torture/execute/pr42512.c: New testcase.
2010-01-09 Tobias Burnus <burnus@net-b.de>
PR fortran/41298

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@ -0,0 +1,13 @@
extern void abort (void);
short g_3;
int main (void)
{
int l_2;
for (l_2 = -1; l_2 != 0; l_2 = (unsigned char)(l_2 - 1))
g_3 |= l_2;
if (g_3 != -1)
abort ();
return 0;
}

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@ -1642,6 +1642,23 @@ interpret_loop_phi (struct loop *loop, gimple loop_phi_node)
init_cond = analyze_initial_condition (loop_phi_node);
res = analyze_evolution_in_loop (loop_phi_node, init_cond);
/* Verify we maintained the correct initial condition throughout
possible conversions in the SSA chain. */
if (res != chrec_dont_know)
{
tree new_init = res;
if (CONVERT_EXPR_P (res)
&& TREE_CODE (TREE_OPERAND (res, 0)) == POLYNOMIAL_CHREC)
new_init = fold_convert (TREE_TYPE (res),
CHREC_LEFT (TREE_OPERAND (res, 0)));
else if (TREE_CODE (res) == POLYNOMIAL_CHREC)
new_init = CHREC_LEFT (res);
STRIP_USELESS_TYPE_CONVERSION (new_init);
gcc_assert (TREE_CODE (new_init) != POLYNOMIAL_CHREC);
if (!operand_equal_p (init_cond, new_init, 0))
return chrec_dont_know;
}
return res;
}