yazdanbakhsh <amir.yazdanbak...@gmail.com> writes:
> I have read all the documents, and changed some lines but nothing happened :(
That is good, but to get help you really need to ask specific
questions. Show us an insn pattern, tell us what you are trying to
do, tell us what you did, tell us what happened.
Ian
> Ian Lance Taylor-3 wrote:
>>
>> yazdanbakhsh <amir.yazdanbak...@gmail.com> writes:
>>
>>> I want to change instruction blez to ble. ble compare two registers and
>>> jump
>>> to the target address if the condition is true.
>>
>> Read the internals manual to understand how operand predicates and
>> constraints work. See the hundreds of existing examples. Ask if you
>> have specific questions.
>>
>> Ian
>>
>>> Ian Lance Taylor-3 wrote:
>>>>
>>>> yazdanbakhsh <amir.yazdanbak...@gmail.com> writes:
>>>>
>>>>> Please assume I'm working with the MIPS. There is a little difference
>>>>> between the MIPS and what I'm actually working on it. How can I remove
>>>>> immediate logical shift right/left from the compiler?
>>>>> I mean If I want the programmer writes an immediate shift, It is
>>>>> compiled
>>>>> to
>>>>> the two instructions:
>>>>>
>>>>> sll %2,%2,5
>>>>>
>>>>> changed to:
>>>>>
>>>>> addi %3,%0,5
>>>>> sllv %2,%2,%3
>>>>
>>>> Find the insn which generates sll. Change the operand constraints and
>>>> predicates to reject an immediate operand.
>>>>
>>>> E.g., in mips.md this is:
>>>>
>>>> (define_insn "*<optab><mode>3"
>>>> [(set (match_operand:GPR 0 "register_operand" "=d")
>>>> (any_shift:GPR (match_operand:GPR 1 "register_operand" "d")
>>>> (match_operand:SI 2 "arith_operand" "dI")))]
>>>> "!TARGET_MIPS16"
>>>> {
>>>> if (CONST_INT_P (operands[2]))
>>>> operands[2] = GEN_INT (INTVAL (operands[2])
>>>> & (GET_MODE_BITSIZE (<MODE>mode) - 1));
>>>>
>>>> return "<d><insn>\t%0,%1,%2";
>>>> }
>>>> [(set_attr "type" "shift")
>>>> (set_attr "mode" "<MODE>")])
>>>>
>>>>
>>>> For operand 2, change the predicate to register_operand and remove the
>>>> 'I' constraint.
>>>>
>>>> Ian
>>>>
>>>>
>>>
>>> --
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>>> Sent from the gcc - Dev mailing list archive at Nabble.com.
>>
>>
>
> --
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