Fix PR/46316

From-SVN: r166469
This commit is contained in:
Xinliang David Li 2010-11-09 02:01:06 +00:00 committed by Xinliang David Li
parent d5214afa12
commit b3a50850b1
6 changed files with 56 additions and 4 deletions

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@ -1,3 +1,11 @@
2010-11-08 Xinliang David Li <davidxl@google.com>
PR/46316
* tree-vrp.c (adjust_range_with_scev): Check double_int
overflow.
* double-int.h (double_int_mul_with_sign): New function.
* double-int.c (double_int_mul_with_sign): New function.
2010-11-08 Paul Koning <ni1d@arrl.net>
* config/pdp11/pdp11.md (lshrsi3, lshrhi3): Fix wrong code.

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@ -718,6 +718,19 @@ double_int_mul (double_int a, double_int b)
return ret;
}
/* Returns A * B. If the operation overflows according to UNSIGNED_P,
*OVERFLOW is set to nonzero. */
double_int
double_int_mul_with_sign (double_int a, double_int b,
bool unsigned_p, int *overflow)
{
double_int ret;
*overflow = mul_double_with_sign (a.low, a.high, b.low, b.high,
&ret.low, &ret.high, unsigned_p);
return ret;
}
/* Returns A + B. */
double_int

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@ -132,6 +132,7 @@ double_int_fits_in_uhwi_p (double_int cst)
2 * HOST_BITS_PER_WIDE_INT bits. */
double_int double_int_mul (double_int, double_int);
double_int double_int_mul_with_sign (double_int, double_int, bool, int *);
double_int double_int_add (double_int, double_int);
double_int double_int_sub (double_int, double_int);
double_int double_int_neg (double_int);

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@ -1,3 +1,8 @@
2010-11-08 Xinliang David Li <davidxl@google.com>
PR/46316
* gcc.dg/tree-ssa/pr46316.c: New test.
2010-11-08 Janus Weil <janus@gcc.gnu.org>
PR fortran/46344

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@ -0,0 +1,20 @@
/* { dg-do run } */
/* { dg-options "-O2" } */
extern void abort (void);
long long __attribute__((noinline,noclone))
foo (long long t)
{
while (t > -4)
t -= 2;
return t;
}
int main(void)
{
if (foo (0) != -4)
abort ();
return 0;
}

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@ -3403,13 +3403,18 @@ adjust_range_with_scev (value_range_t *vr, struct loop *loop,
{
value_range_t maxvr = { VR_UNDEFINED, NULL_TREE, NULL_TREE, NULL };
double_int dtmp;
dtmp = double_int_mul (tree_to_double_int (step),
double_int_sub (loop->nb_iterations_upper_bound,
double_int_one));
bool unsigned_p = TYPE_UNSIGNED (TREE_TYPE (step));
int overflow = 0;
dtmp = double_int_mul_with_sign (tree_to_double_int (step),
double_int_sub (
loop->nb_iterations_upper_bound,
double_int_one),
unsigned_p, &overflow);
tem = double_int_to_tree (TREE_TYPE (init), dtmp);
/* If the multiplication overflowed we can't do a meaningful
adjustment. */
if (double_int_equal_p (dtmp, tree_to_double_int (tem)))
if (!overflow && double_int_equal_p (dtmp, tree_to_double_int (tem)))
{
extract_range_from_binary_expr (&maxvr, PLUS_EXPR,
TREE_TYPE (init), init, tem);