Hello Jeff:
Please review Jeff.
Thanks & Regards
Ajit
On 12/05/23 4:48 pm, Ajit Agarwal via Gcc-patches wrote:
> Hello Jeff:
>
>
> On 29/04/23 3:40 am, Jeff Law wrote:
>>
>>
>> On 4/20/23 15:03, Ajit Agarwal wrote:
>>
>>>
>>> Currently I support AND with const1_rtx. This is what is equivalent to zero
>>> extension instruction in power instruction set. When you specify many other
>>> constants and Could you please specify what other constants needs to be
>>> supported and how to determine on the Input and output modes.
>> x AND <constant> will result in a zero-extended representation for a variety
>> of constants, not just 1. For example
>>
>> For example x AND 3, x AND 7, x AND 15, etc.
>>
>> If (const_int 1) is really that special here, then I've either completely
>> misunderstood the intention of your patch or there's something quite special
>> about the PPC port that I'm not aware of.
>>
>
> Here is the patch to address above.
>
> ree: Improve ree pass for rs6000 target
>
> For rs6000 target we see redundant zero and sign
> extension and done to improve ree pass to eliminate
> such redundant zero and sign extension. Support of
> AND with extension with different constants other
> than 1.
>
> 2023-05-12 Ajit Kumar Agarwal <aagar...@linux.ibm.com>
>
> gcc/ChangeLog:
>
> * ree.cc (rtx_is_zext_p): Add AND with varying contsants as
> extensions.
> ---
> gcc/ree.cc | 15 ++++++++++-----
> 1 file changed, 10 insertions(+), 5 deletions(-)
>
> diff --git a/gcc/ree.cc b/gcc/ree.cc
> index 96fda1ac658..ddda5f194bb 100644
> --- a/gcc/ree.cc
> +++ b/gcc/ree.cc
> @@ -269,8 +269,11 @@ rtx_is_zext_p (rtx insn)
> rtx set = XEXP (insn, 0);
> if (REG_P (set))
> {
> - if (XEXP (insn, 1) == const1_rtx)
> - return true;
> + rtx src = XEXP (insn, 1);
> +
> + if (CONST_INT_P (src)
> + && IN_RANGE (exact_log2 (UINTVAL (src)), 0, 7))
> + return true;
> }
> else
> return false;
> @@ -297,9 +300,11 @@ rtx_is_zext_p (rtx_insn *insn)
>
> if (REG_P (set) && GET_MODE (SET_DEST (body)) == GET_MODE (set))
> {
> - if (GET_MODE_UNIT_SIZE (GET_MODE (SET_DEST (body)))
> - >= GET_MODE_UNIT_SIZE (GET_MODE (set)))
> - return true;
> + rtx src = XEXP (SET_SRC (body), 1);
> +
> + if (CONST_INT_P (src)
> + && IN_RANGE (exact_log2 (UINTVAL (src)), 0, 7))
> + return true;
> }
> else
> return false;
