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re PR middle-end/49840 (New test failures)

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2011-07-26  Richard Guenther  <rguenther@suse.de>

	PR tree-optimization/49840
	* tree-vrp.c (range_fits_type_p): Properly handle full
	double-int precision.

From-SVN: r176790
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Richard Guenther 2011-07-26 12:37:00 +00:00 • committed by Richard Biener
parent 5bf3d50db7
commit 9f61fd1747
2 changed files with 30 additions and 2 deletions
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6
gcc/ChangeLog
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@ -1,3 +1,9 @@
2011-07-26 Richard Guenther <rguenther@suse.de>
PR tree-optimization/49840
* tree-vrp.c (range_fits_type_p): Properly handle full
double-int precision.
2011-07-26 Martin Jambor <mjambor@suse.cz>
PR bootstrap/49786

26
gcc/tree-vrp.c
View file

@ -7423,18 +7423,40 @@ simplify_conversion_using_ranges (gimple stmt)
static bool
range_fits_type_p (value_range_t *vr, unsigned precision, bool unsigned_p)
{
tree src_type;
unsigned src_precision;
double_int tem;
/* We can only handle constant ranges. */
/* We can only handle integral and pointer types. */
src_type = TREE_TYPE (vr->min);
if (!INTEGRAL_TYPE_P (src_type)
&& !POINTER_TYPE_P (src_type))
return false;
/* An extension is always fine, so is an identity transform. */
src_precision = TYPE_PRECISION (TREE_TYPE (vr->min));
if (src_precision < precision
|| (src_precision == precision
&& TYPE_UNSIGNED (src_type) == unsigned_p))
return true;
/* Now we can only handle ranges with constant bounds. */
if (vr->type != VR_RANGE
|| TREE_CODE (vr->min) != INTEGER_CST
|| TREE_CODE (vr->max) != INTEGER_CST)
return false;
/* For precision-preserving sign-changes the MSB of the double-int
has to be clear. */
if (src_precision == precision
&& (TREE_INT_CST_HIGH (vr->min) | TREE_INT_CST_HIGH (vr->max)) < 0)
return false;
/* Then we can perform the conversion on both ends and compare
the result for equality. */
tem = double_int_ext (tree_to_double_int (vr->min), precision, unsigned_p);
if (!double_int_equal_p (tree_to_double_int (vr->min), tem))
return false;
tem = double_int_ext (tree_to_double_int (vr->max), precision, unsigned_p);
if (!double_int_equal_p (tree_to_double_int (vr->max), tem))
return false;