PR middle-end/103406: Check for Inf before simplifying x-x.
This is a simple one line fix to the regression PR middle-end/103406, where x - x is being folded to 0.0 even when x is +Inf or -Inf. In GCC 11 and previously, we'd check whether the type honored NaNs (which implicitly covered the case where the type honors infinities), but my patch to test whether the operand could potentially be NaN failed to also check whether the operand could potentially be Inf. 2021-11-25 Roger Sayle <roger@nextmovesoftware.com> gcc/ChangeLog PR middle-end/103406 * match.pd (minus @0 @0): Check tree_expr_maybe_infinite_p. gcc/testsuite/ChangeLog PR middle-end/103406 * gcc.dg/pr103406.c: New test case.
This commit is contained in:
parent
9488d24206
commit
6ea5fb3cc7
|
@ -233,7 +233,9 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
|
|||
is volatile. */
|
||||
(simplify
|
||||
(minus @0 @0)
|
||||
(if (!FLOAT_TYPE_P (type) || !tree_expr_maybe_nan_p (@0))
|
||||
(if (!FLOAT_TYPE_P (type)
|
||||
|| (!tree_expr_maybe_nan_p (@0)
|
||||
&& !tree_expr_maybe_infinite_p (@0)))
|
||||
{ build_zero_cst (type); }))
|
||||
(simplify
|
||||
(pointer_diff @@0 @0)
|
||||
|
|
|
@ -0,0 +1,14 @@
|
|||
/* { dg-do compile } */
|
||||
/* { dg-options "-O2 -fdump-tree-optimized" } */
|
||||
|
||||
#define HUGE __DBL_MAX__
|
||||
#define INF (HUGE + HUGE)
|
||||
#define NAN (INF - INF)
|
||||
|
||||
double foo() {
|
||||
double x = -NAN;
|
||||
double y = NAN;
|
||||
return x + y;
|
||||
}
|
||||
|
||||
/* { dg-final { scan-tree-dump-not "return 0\.0" "optimized" } } */
|
Loading…
Reference in New Issue