On 09/22/2015 01:20 PM, Richard Henderson wrote:
On 09/22/2015 12:18 PM, Jeff Law wrote:
On 09/22/2015 01:15 PM, Richard Henderson wrote:
And doesn't it have to be =& and always at the start for an asm constraint?
For operands in patterns, we have to consider operand alternatives, but that's
no
On 09/22/2015 12:18 PM, Jeff Law wrote:
> On 09/22/2015 01:15 PM, Richard Henderson wrote:
>>> And doesn't it have to be =& and always at the start for an asm constraint?
>>> For operands in patterns, we have to consider operand alternatives, but
>>> that's
>>> not on issue here.
>>
>> Technically
On 09/22/2015 01:15 PM, Richard Henderson wrote:
And doesn't it have to be =& and always at the start for an asm constraint?
For operands in patterns, we have to consider operand alternatives, but that's
not on issue here.
Technically we do support alternatives on asms. Not usefully except for
On 09/22/2015 12:12 PM, Jeff Law wrote:
> On 09/22/2015 12:50 PM, Richard Henderson wrote:
>>
>>> +asm_constraint_earlyclobber (const char *constraint)
>>> +{
>>> + while (*constraint != 0)
>>> +{
>>> + if (*constraint == '&')
>>> +return true;
>>> + ++constraint;
>>> +}
>>>
On 09/22/2015 12:50 PM, Richard Henderson wrote:
+asm_constraint_earlyclobber (const char *constraint)
+{
+ while (*constraint != 0)
+{
+ if (*constraint == '&')
+ return true;
+ ++constraint;
+}
+ return false;
+}
This would be
return strchr (constraint, '&') !=
> + /* Registers that can not be allocated for this allocno, for example
> because
> + there is an ASM_OPERANDS with that register as an output and this pseudo
> + as an earlyclobber input. */
> + HARD_REG_SET forbidden_regs;
You mean "with that register as an earlyclobber output and t
When using an asm register variable as an input or output operand for an
inline assembler block, GCC guarantees that the specified register is
used for the operand in question (see
https://gcc.gnu.org/onlinedocs/gcc/Local-Reg-Vars.html). Together with
earlyclobber constraints
(https://gcc.gnu.
