rtlanal: Fix up replace_rtx [PR105333]

The following testcase FAILs, because replace_rtx replaces a REG with
CONST_WIDE_INT inside of a SUBREG, which is an invalid transformation
because a SUBREG relies on SUBREG_REG having non-VOIDmode but
CONST_WIDE_INT has VOIDmode.

replace_rtx already has code to deal with it, but it was doing
it only for CONST_INTs.  The following patch does it also for
VOIDmode CONST_DOUBLE or CONST_WIDE_INT.

2022-04-22  Jakub Jelinek  <jakub@redhat.com>

	PR rtl-optimization/105333
	* rtlanal.cc (replace_rtx): Use simplify_subreg or
	simplify_unary_operation if CONST_SCALAR_INT_P rather than just
	CONST_INT_P.

	* gcc.dg/pr105333.c: New test.
This commit is contained in:
Jakub Jelinek 2022-04-22 13:38:11 +02:00
parent c1a9cf6791
commit 7092b7aea1
2 changed files with 23 additions and 2 deletions

View File

@ -3390,7 +3390,7 @@ replace_rtx (rtx x, rtx from, rtx to, bool all_regs)
{
rtx new_rtx = replace_rtx (SUBREG_REG (x), from, to, all_regs);
if (CONST_INT_P (new_rtx))
if (CONST_SCALAR_INT_P (new_rtx))
{
x = simplify_subreg (GET_MODE (x), new_rtx,
GET_MODE (SUBREG_REG (x)),
@ -3406,7 +3406,7 @@ replace_rtx (rtx x, rtx from, rtx to, bool all_regs)
{
rtx new_rtx = replace_rtx (XEXP (x, 0), from, to, all_regs);
if (CONST_INT_P (new_rtx))
if (CONST_SCALAR_INT_P (new_rtx))
{
x = simplify_unary_operation (ZERO_EXTEND, GET_MODE (x),
new_rtx, GET_MODE (XEXP (x, 0)));

View File

@ -0,0 +1,21 @@
/* PR rtl-optimization/105333 */
/* { dg-do compile { target int128 } } */
/* { dg-options "-Og -fno-tree-coalesce-vars -fno-tree-fre" } */
int g;
short s;
static inline unsigned short
bar (short a, __int128 b)
{
b ^= (unsigned long) -a;
__builtin_strncpy ((void *) &s, (void *) &a, 1);
b *= 14;
return b;
}
void
foo (void)
{
g *= (__int128) bar (1, 1);
}