i386: Return true for (SUBREG (MEM....)) in register_no_elim_operand [PR105927]

Under certain conditions register_operand predicate also allows
subregs of memory operands.  When RTL checking is enabled, these
will fail with REGNO (op).

Allow subregs of memory operands, these are guaranteed
to be reloaded to a register.

2022-06-13  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:

	PR target/105927
	* config/i386/predicates.md (register_no_elim_operand):
	Return true for subreg of a memory operand.

gcc/testsuite/ChangeLog:

	PR target/105927
	* gcc.target/i386/pr105927.c: New test.
This commit is contained in:
Uros Bizjak 2022-06-13 17:08:18 +02:00
parent 77718f38f8
commit b3dd7d8b48
2 changed files with 25 additions and 0 deletions

View file

@ -672,6 +672,12 @@
{
if (SUBREG_P (op))
op = SUBREG_REG (op);
/* Before reload, we can allow (SUBREG (MEM...)) as a register operand
because it is guaranteed to be reloaded into one. */
if (MEM_P (op))
return true;
return !(op == arg_pointer_rtx
|| op == frame_pointer_rtx
|| IN_RANGE (REGNO (op),
@ -685,6 +691,7 @@
{
if (SUBREG_P (op))
op = SUBREG_REG (op);
if (reload_completed)
return REG_OK_FOR_INDEX_STRICT_P (op);
else

View file

@ -0,0 +1,18 @@
/* PR target/105927 */
/* { dg-do compile { target ia32 } } */
/* { dg-options "-O1 -fno-tree-dce -mtune=k6-3 -msse2" } */
typedef _Float16 __attribute__((__vector_size__(4))) U;
typedef _Float16 __attribute__((__vector_size__(2))) V;
typedef short __attribute__((__vector_size__(4))) W;
V v;
U u;
extern void bar(W i);
void
foo(void)
{
U x = __builtin_shufflevector(v, u, 2, 0);
bar(x >= 0);
}