Hello Vineet:
This patch is without sign_extension implementation.
I have sent patch 8 that incorporates sign_extension using abi interfaces.
Please review.
Thanks & Regards
Ajit
On 19/09/23 2:48 pm, Ajit Agarwal wrote:
>
>
> On 19/09/23 2:36 pm, Xi Ruoyao wrote:
>> On Tue, 2023-09-19 at 14:29 +0530, Ajit Agarwal wrote:
>>> This new version of patch 7 use improve ree pass for rs6000 target
>>> using defined ABI interfaces.
>>> Bootstrapped and regtested on power64-linux-gnu.
>>
>> You should drop the "4/4" in subject if it does not depends on other
>> non-committed patches. Otherwise you should send all the non-committed
>> dependencies in a series.
>>
>> If you just have the 4/4 there without {1..3}/4, people will believe
>> this is an incomplete patch submission and likely ignore it.
>>
>
> There are 4 oatches that are already under review and all the provious
> patches are under review.
>
> I will send 3/4 patches again for review.
>
> Thanks & Regards
> Ajit
>>> Review comments incorporated.
>>>
>>> Thanks & Regards
>>> Ajit
>>>
>>> ree: Improve ree pass for rs6000 target using defined abi interfaces
>>>
>>> For rs6000 target we see redundant zero and sign extension and done to
>>> improve ree pass to eliminate such redundant zero and sign extension
>>> using defined ABI interfaces.
>>>
>>> 2023-09-19 Ajit Kumar Agarwal <aagar...@linux.ibm.com>
>>>
>>> gcc/ChangeLog:
>>>
>>> * ree.cc (combine_reaching_defs): Use of zero_extend and
>>> sign_extend
>>> defined abi interfaces.
>>> (add_removable_extension): Use of defined abi interfaces for
>>> no
>>> reaching defs.
>>> (abi_extension_candidate_return_reg_p): New function.
>>> (abi_extension_candidate_p): New function.
>>> (abi_extension_candidate_argno_p): New function.
>>> (abi_handle_regs_without_defs_p): New function.
>>> (abi_target_promote_function_mode): New function.
>>>
>>> gcc/testsuite/ChangeLog:
>>>
>>> * g++.target/powerpc/zext-elim-3.C
>>> ---
>>> gcc/ree.cc | 148
>>> +++++++++++++++++-
>>> .../g++.target/powerpc/zext-elim-3.C | 13 ++
>>> 2 files changed, 158 insertions(+), 3 deletions(-)
>>> create mode 100644 gcc/testsuite/g++.target/powerpc/zext-elim-3.C
>>>
>>> diff --git a/gcc/ree.cc b/gcc/ree.cc
>>> index fc04249fa84..79fc54f38a3 100644
>>> --- a/gcc/ree.cc
>>> +++ b/gcc/ree.cc
>>> @@ -514,7 +514,8 @@ get_uses (rtx_insn *insn, rtx reg)
>>> if (REGNO (DF_REF_REG (def)) == REGNO (reg))
>>> break;
>>>
>>> - gcc_assert (def != NULL);
>>> + if (def == NULL)
>>> + return NULL;
>>>
>>> ref_chain = DF_REF_CHAIN (def);
>>>
>>> @@ -750,6 +751,122 @@ get_extended_src_reg (rtx src)
>>> return src;
>>> }
>>>
>>> +/* Return TRUE if target mode is equal to source mode of zero_extend
>>> + or sign_extend otherwise false. */
>>> +
>>> +static bool
>>> +abi_target_promote_function_mode (machine_mode mode)
>>> +{
>>> + int unsignedp;
>>> + machine_mode tgt_mode
>>> + = targetm.calls.promote_function_mode (NULL_TREE, mode,
>>> &unsignedp,
>>> + NULL_TREE, 1);
>>> +
>>> + if (tgt_mode == mode)
>>> + return true;
>>> + else
>>> + return false;
>>> +}
>>> +
>>> +/* Return TRUE if the candidate insn is zero extend and regno is
>>> + a return registers. */
>>> +
>>> +static bool
>>> +abi_extension_candidate_return_reg_p (rtx_insn *insn, int regno)
>>> +{
>>> + rtx set = single_set (insn);
>>> +
>>> + if (GET_CODE (SET_SRC (set)) != ZERO_EXTEND)
>>> + return false;
>>> +
>>> + if (targetm.calls.function_value_regno_p (regno))
>>> + return true;
>>> +
>>> + return false;
>>> +}
>>> +
>>> +/* Return TRUE if reg source operand of zero_extend is argument
>>> registers
>>> + and not return registers and source and destination operand are
>>> same
>>> + and mode of source and destination operand are not same. */
>>> +
>>> +static bool
>>> +abi_extension_candidate_p (rtx_insn *insn)
>>> +{
>>> + rtx set = single_set (insn);
>>> +
>>> + if (GET_CODE (SET_SRC (set)) != ZERO_EXTEND)
>>> + return false;
>>> +
>>> + machine_mode dst_mode = GET_MODE (SET_DEST (set));
>>> + rtx orig_src = XEXP (SET_SRC (set), 0);
>>> +
>>> + if (!FUNCTION_ARG_REGNO_P (REGNO (orig_src))
>>> + || abi_extension_candidate_return_reg_p (insn, REGNO
>>> (orig_src)))
>>> + return false;
>>> +
>>> + /* Mode of destination and source of zero_extend should be
>>> different. */
>>> + if (dst_mode == GET_MODE (orig_src))
>>> + return false;
>>> +
>>> + /* REGNO of source and destination of zero_extend should be same.
>>> */
>>> + if (REGNO (SET_DEST (set)) != REGNO (orig_src))
>>> + return false;
>>> +
>>> + return true;
>>> +}
>>> +
>>> +/* Return TRUE if the candidate insn is zero extend and regno is
>>> + an argument registers. */
>>> +
>>> +static bool
>>> +abi_extension_candidate_argno_p (rtx_code code, int regno)
>>> +{
>>> + if (code != ZERO_EXTEND && code != SIGN_EXTEND)
>>> + return false;
>>> +
>>> + if (FUNCTION_ARG_REGNO_P (regno))
>>> + return true;
>>> +
>>> + return false;
>>> +}
>>> +
>>> +/* Return TRUE if the candidate insn doesn't have defs and have
>>> + * uses without RTX_BIN_ARITH/RTX_COMM_ARITH/RTX_UNARY rtx class. */
>>> +
>>> +static bool
>>> +abi_handle_regs_without_defs_p (rtx_insn *insn)
>>> +{
>>> + if (side_effects_p (PATTERN (insn)))
>>> + return false;
>>> +
>>> + struct df_link *uses = get_uses (insn, SET_DEST (PATTERN (insn)));
>>> +
>>> + if (!uses)
>>> + return false;
>>> +
>>> + for (df_link *use = uses; use; use = use->next)
>>> + {
>>> + if (!use->ref)
>>> + return false;
>>> +
>>> + if (BLOCK_FOR_INSN (insn) != BLOCK_FOR_INSN (DF_REF_INSN (use-
>>>> ref)))
>>> + return false;
>>> +
>>> + rtx_insn *use_insn = DF_REF_INSN (use->ref);
>>> +
>>> + if (GET_CODE (PATTERN (use_insn)) == SET)
>>> + {
>>> + rtx_code code = GET_CODE (SET_SRC (PATTERN (use_insn)));
>>> +
>>> + if (GET_RTX_CLASS (code) == RTX_BIN_ARITH
>>> + || GET_RTX_CLASS (code) == RTX_COMM_ARITH
>>> + || GET_RTX_CLASS (code) == RTX_UNARY)
>>> + return false;
>>> + }
>>> + }
>>> + return true;
>>> +}
>>> +
>>> /* This function goes through all reaching defs of the source
>>> of the candidate for elimination (CAND) and tries to combine
>>> the extension with the definition instruction. The changes
>>> @@ -770,6 +887,11 @@ combine_reaching_defs (ext_cand *cand, const_rtx
>>> set_pat, ext_state *state)
>>>
>>> state->defs_list.truncate (0);
>>> state->copies_list.truncate (0);
>>> + rtx orig_src = XEXP (SET_SRC (cand->expr),0);
>>> +
>>> + if (abi_extension_candidate_p (cand->insn)
>>> + && (!get_defs (cand->insn, orig_src, NULL)))
>>> + return abi_handle_regs_without_defs_p (cand->insn);
>>>
>>> outcome = make_defs_and_copies_lists (cand->insn, set_pat, state);
>>>
>>> @@ -1036,6 +1158,15 @@ combine_reaching_defs (ext_cand *cand,
>>> const_rtx set_pat, ext_state *state)
>>> }
>>> }
>>>
>>> + rtx insn_set = single_set (cand->insn);
>>> +
>>> + machine_mode mode = (GET_MODE (XEXP (SET_SRC (insn_set), 0)));
>>> +
>>> + bool promote_p = abi_target_promote_function_mode (mode);
>>> +
>>> + if (promote_p)
>>> + return true;
>>> +
>>> if (merge_successful)
>>> {
>>> /* Commit the changes here if possible
>>> @@ -1112,6 +1243,7 @@ add_removable_extension (const_rtx expr,
>>> rtx_insn *insn,
>>> rtx reg = XEXP (src, 0);
>>> struct df_link *defs, *def;
>>> ext_cand *cand;
>>> + defs = get_defs (insn, reg, NULL);
>>>
>>> /* Zero-extension of an undefined value is partly defined (it's
>>> completely undefined for sign-extension, though). So if
>>> there exists
>>> @@ -1131,9 +1263,14 @@ add_removable_extension (const_rtx expr,
>>> rtx_insn *insn,
>>> }
>>>
>>> /* Second, make sure we can get all the reaching definitions.
>>> */
>>> - defs = get_defs (insn, reg, NULL);
>>> if (!defs)
>>> {
>>> + if (abi_extension_candidate_argno_p (code, REGNO (reg)))
>>> + {
>>> + ext_cand e = {expr, code, mode, insn};
>>> + insn_list->safe_push (e);
>>> + return;
>>> + }
>>> if (dump_file)
>>> {
>>> fprintf (dump_file, "Cannot eliminate extension:\n");
>>> @@ -1321,7 +1458,8 @@ find_and_remove_re (void)
>>> && (REGNO (SET_DEST (set)) != REGNO (XEXP (SET_SRC
>>> (set), 0))))
>>> {
>>> reinsn_copy_list.safe_push (curr_cand->insn);
>>> - reinsn_copy_list.safe_push (state.defs_list[0]);
>>> + if (state.defs_list.length () != 0)
>>> + reinsn_copy_list.safe_push (state.defs_list[0]);
>>> }
>>> reinsn_del_list.safe_push (curr_cand->insn);
>>> state.modified[INSN_UID (curr_cand->insn)].deleted = 1;
>>> @@ -1345,6 +1483,10 @@ find_and_remove_re (void)
>>> for (unsigned int i = 0; i < reinsn_copy_list.length (); i += 2)
>>> {
>>> rtx_insn *curr_insn = reinsn_copy_list[i];
>>> +
>>> + if ((i+1) >= reinsn_copy_list.length ())
>>> + continue;
>>> +
>>> rtx_insn *def_insn = reinsn_copy_list[i + 1];
>>>
>>> /* Use the mode of the destination of the defining insn
>>> diff --git a/gcc/testsuite/g++.target/powerpc/zext-elim-3.C
>>> b/gcc/testsuite/g++.target/powerpc/zext-elim-3.C
>>> new file mode 100644
>>> index 00000000000..5a050df06ff
>>> --- /dev/null
>>> +++ b/gcc/testsuite/g++.target/powerpc/zext-elim-3.C
>>> @@ -0,0 +1,13 @@
>>> +/* { dg-options "-mcpu=power9 -O2" } */
>>> +
>>> +void *memset(void *b, int c, unsigned long len)
>>> +{
>>> + unsigned long i;
>>> +
>>> + for (i = 0; i < len; i++)
>>> + ((unsigned char *)b)[i] = c;
>>> +
>>> + return b;
>>> +}
>>> +
>>> +/* { dg-final { scan-assembler-not "\mrlwinm\M" } } */
>>
