Bin Cheng <bin.ch...@arm.com> writes:
> diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr71347.c
> b/gcc/testsuite/gcc.dg/tree-ssa/pr71347.c
> new file mode 100644
> index 0000000..7e5ad49
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/tree-ssa/pr71347.c
> @@ -0,0 +1,17 @@
> +/* { dg-do compile } */
> +/* { dg-options "-O2 -fdump-tree-optimized" } */
> +
> +double in;
> +extern void Write (double);
> +void foo (void)
> +{
> + static double X[9];
> + int i;
> + X[1] = in * in;
> + for (i = 2; i <= 8; i++)
> + X[i] = X[i - 1] * X[1];
> + Write (X[5]);
> +}
> +
> +/* Load of X[i - i] can be omitted by reusing X[i] in previous iteration. */
> +/* { dg-final { scan-tree-dump-not ".* = MEM.*;" "optimized"} } */
The test fails on ia64, this is what I get in .optimized:
;; Function foo (foo, funcdef_no=0, decl_uid=1387, cgraph_uid=0, symbol_order=1)
foo ()
{
int i;
static double X[9];
double in.0_1;
double in.1_2;
double _3;
int _4;
double _5;
double _6;
double _7;
double _8;
<bb 2>:
in.0_1 = in;
in.1_2 = in;
_3 = in.0_1 * in.1_2;
X[1] = _3;
i_13 = 2;
goto <bb 4>;
<bb 3>:
_4 = i_9 + -1;
_5 = X[_4];
_6 = X[1];
_7 = _5 * _6;
X[i_9] = _7;
i_15 = i_9 + 1;
<bb 4>:
# i_9 = PHI <i_13(2), i_15(3)>
if (i_9 <= 8)
goto <bb 3>;
else
goto <bb 5>;
<bb 5>:
_8 = X[5];
Write (_8);
return;
}
Andreas.
--
Andreas Schwab, sch...@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756 01D3 44D5 214B 8276 4ED5
"And now for something completely different."
