re PR middle-end/27136 (Compile failure with -O -ffast-math)

2006-05-07  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/27136
	* tree-ssa-loop-niter.c (get_val_for): Correct function
	comment, assert requirements.
	(loop_niter_by_eval): Stop processing if the iterated
	value did not simplify.

	* gcc.dg/torture/pr27136.c: New testcase.

From-SVN: r113601
This commit is contained in:
Richard Guenther 2006-05-07 13:07:22 +00:00 committed by Richard Biener
parent ef5d0a896e
commit ed52affe53
4 changed files with 31 additions and 2 deletions

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@ -1,3 +1,11 @@
2006-05-07 Richard Guenther <rguenther@suse.de>
PR tree-optimization/27136
* tree-ssa-loop-niter.c (get_val_for): Correct function
comment, assert requirements.
(loop_niter_by_eval): Stop processing if the iterated
value did not simplify.
2006-05-07 Mircea Namolaru <namolaru@il.ibm.com>
* opts.c (flag_see): remove its setting at -O3.

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@ -1,3 +1,8 @@
2006-05-07 Richard Guenther <rguenther@suse.de>
PR tree-optimization/27136
* gcc.dg/torture/pr27136.c: New testcase.
2006-05-07 Paul Thomas <pault@gcc.gnu.org>
PR fortran/24813

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@ -0,0 +1,10 @@
/* { dg-do compile } */
/* { dg-options "-ffast-math" } */
void foo()
{
double x;
for (x = 2; x < 10; x *= x)
;
}

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@ -1301,7 +1301,7 @@ get_base_for (struct loop *loop, tree x)
/* Given an expression X, then
* if BASE is NULL_TREE, X must be a constant and we return X.
* if X is NULL_TREE, we return the constant BASE.
* otherwise X is a SSA name, whose value in the considered loop is derived
by a chain of operations with constant from a result of a phi node in
the header of the loop. Then we return value of X when the value of the
@ -1314,6 +1314,8 @@ get_val_for (tree x, tree base)
use_operand_p op;
ssa_op_iter iter;
gcc_assert (is_gimple_min_invariant (base));
if (!x)
return base;
@ -1414,7 +1416,11 @@ loop_niter_by_eval (struct loop *loop, edge exit)
}
for (j = 0; j < 2; j++)
val[j] = get_val_for (next[j], val[j]);
{
val[j] = get_val_for (next[j], val[j]);
if (!is_gimple_min_invariant (val[j]))
return chrec_dont_know;
}
}
return chrec_dont_know;