https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67653
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Bet r140431. The issue seems to be that the FEs make the "m" operand
addressable:
if (parse_output_constraint (&constraint, i, ninputs, noutputs,
&allows_mem, &allows_reg, &is_inout))
{
/* If the operand is going to end up in memory,
mark it addressable. */
if (!allows_reg && !cxx_mark_addressable (operand))
operand = error_mark_node;
}
or:
if (!allows_reg && allows_mem)
{
input = c_fully_fold (input, false, NULL);
/* Strip the nops as we allow this case. FIXME, this really
should be rejected or made deprecated. */
STRIP_NOPS (input);
if (!c_mark_addressable (input))
input = error_mark_node;
}
but for the case of a statement expression that doesn't mark it addressable.
Then during gimplify_asm_expr we:
5281 tret = gimplify_expr (&TREE_VALUE (link), pre_p, post_p,
5282 is_gimple_lvalue, fb_lvalue |
fb_mayfail);
5283 mark_addressable (TREE_VALUE (link));
5284 if (tret == GS_ERROR)
and in this case tref actually is not GS_ERROR, as it is gimplified to an
artificial decl from a TARGET_EXPR. But it marks addressable something that
has been already used.
No idea what to do here. For "=m" we require lvalue_or_else (after doing a
hack and stripping nops), but for the input operands we don't.
So perhaps just replace the mark_addressable call with something like:
tree x = TREE_VALUE (link);
while (handled_component_p (x))
x = TREE_OPERAND (x, 0);
if (TREE_CODE (x) == MEM_REF
&& TREE_CODE (TREE_OPERAND (x, 0)) == ADDR_EXPR)
x = TREE_OPERAND (TREE_OPERAND (x, 0), 0);
if ((TREE_CODE (x) == VAR_DECL
|| TREE_CODE (x) == PARM_DECL
|| TREE_CODE (x) == RESULT_DECL)
&& !TREE_ADDRESSABLE (x))
{
error ("memory input %d is not directly addressable", i);
ret = GS_ERROR;
}
