From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0b-001b2d01.pphosted.com [148.163.158.5]) by sourceware.org (Postfix) with ESMTPS id 6D89D3858D1E; Wed, 17 Aug 2022 03:12:30 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 6D89D3858D1E Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.17.1.5/8.17.1.5) with ESMTP id 27H2NaEG002504; Wed, 17 Aug 2022 03:12:30 GMT Received: from pps.reinject (localhost [127.0.0.1]) by mx0b-001b2d01.pphosted.com (PPS) with ESMTPS id 3j0qgf8xp5-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Aug 2022 03:12:29 +0000 Received: from m0098419.ppops.net (m0098419.ppops.net [127.0.0.1]) by pps.reinject (8.17.1.5/8.17.1.5) with ESMTP id 27H3CCl1014746; Wed, 17 Aug 2022 03:12:28 GMT Received: from ppma04dal.us.ibm.com (7a.29.35a9.ip4.static.sl-reverse.com [169.53.41.122]) by mx0b-001b2d01.pphosted.com (PPS) with ESMTPS id 3j0qgf8xny-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Aug 2022 03:12:28 +0000 Received: from pps.filterd (ppma04dal.us.ibm.com [127.0.0.1]) by ppma04dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 27H36dqm002561; Wed, 17 Aug 2022 03:12:28 GMT Received: from b03cxnp07027.gho.boulder.ibm.com (b03cxnp07027.gho.boulder.ibm.com [9.17.130.14]) by ppma04dal.us.ibm.com with ESMTP id 3hx3ka396w-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 17 Aug 2022 03:12:27 +0000 Received: from b03ledav001.gho.boulder.ibm.com (b03ledav001.gho.boulder.ibm.com [9.17.130.232]) by b03cxnp07027.gho.boulder.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 27H3CQmJ41157032 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 17 Aug 2022 03:12:26 GMT Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id DB95C6E052; Wed, 17 Aug 2022 03:12:26 +0000 (GMT) Received: from b03ledav001.gho.boulder.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 985A66E050; Wed, 17 Aug 2022 03:12:26 +0000 (GMT) Received: from pike (unknown [9.5.12.127]) by b03ledav001.gho.boulder.ibm.com (Postfix) with ESMTPS; Wed, 17 Aug 2022 03:12:26 +0000 (GMT) From: Jiufu Guo To: gcc-patches@gcc.gnu.org Cc: segher@kernel.crashing.org, dje.gcc@gmail.com, linkw@gcc.gnu.org Subject: Re: [PATCH V4] rs6000: Optimize cmp on rotated 16bits constant References: <20220725132922.45470-1-guojiufu@linux.ibm.com> Date: Wed, 17 Aug 2022 11:12:23 +0800 In-Reply-To: <20220725132922.45470-1-guojiufu@linux.ibm.com> (Jiufu Guo's message of "Mon, 25 Jul 2022 21:29:22 +0800") Message-ID: <7e7d37k1go.fsf@pike.rch.stglabs.ibm.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/25.2 (gnu/linux) Content-Type: text/plain X-TM-AS-GCONF: 00 X-Proofpoint-GUID: aWGFm25qo24GObk0BilJ1TcV_bjRhfQL X-Proofpoint-ORIG-GUID: ASAqZr-NDdACtMXpVsWBcN754oRBXYL- X-Proofpoint-UnRewURL: 0 URL was un-rewritten MIME-Version: 1.0 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.883,Hydra:6.0.517,FMLib:17.11.122.1 definitions=2022-08-17_02,2022-08-16_02,2022-06-22_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 bulkscore=0 suspectscore=0 adultscore=0 malwarescore=0 mlxscore=0 clxscore=1015 phishscore=0 mlxlogscore=999 spamscore=0 priorityscore=1501 impostorscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2207270000 definitions=main-2208170011 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_MSPIKE_H2, SPF_HELO_NONE, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 17 Aug 2022 03:12:34 -0000 Gentle ping: https://gcc.gnu.org/pipermail/gcc-patches/2022-July/598769.html BR, Jeff(Jiufu) Jiufu Guo writes: > Hi, > > When checking eq/neq with a constant which has only 16bits, it can be > optimized to check the rotated data. By this, the constant building > is optimized. > > As the example in PR103743: > For "in == 0x8000000000000000LL", this patch generates: > rotldi %r3,%r3,16 > cmpldi %cr0,%r3,32768 > instead: > li %r9,-1 > rldicr %r9,%r9,0,0 > cmpd %cr0,%r3,%r9 > > This is a new patch to optimize compare(eq/ne) on rotatable constant. > This patch would be more straitforward than previous patch, like: > https://gcc.gnu.org/pipermail/gcc-patches/2022-May/595576.html. > > This patch pass bootstrap and regtest on ppc64 and ppc64le. > Is it ok for trunk? Thanks for comments! > > BR, > Jeff(Jiufu) > > > PR target/103743 > > gcc/ChangeLog: > > * config/rs6000/rs6000-protos.h (rotate_from_leading_zeros_const): > New decl. > * config/rs6000/rs6000.cc (rotate_from_leading_zeros_const): New > define for checking simply rotated constant. > * config/rs6000/rs6000.md (*rotate_on_cmpdi): New > define_insn_and_split to optimze comparing on rotated constant. > > gcc/testsuite/ChangeLog: > > * gcc.target/powerpc/pr103743.c: New test. > * gcc.target/powerpc/pr103743_1.c: New test. > > --- > gcc/config/rs6000/rs6000-protos.h | 1 + > gcc/config/rs6000/rs6000.cc | 29 ++++++ > gcc/config/rs6000/rs6000.md | 54 ++++++++++- > gcc/testsuite/gcc.target/powerpc/pr103743.c | 52 ++++++++++ > gcc/testsuite/gcc.target/powerpc/pr103743_1.c | 95 +++++++++++++++++++ > 5 files changed, 230 insertions(+), 1 deletion(-) > create mode 100644 gcc/testsuite/gcc.target/powerpc/pr103743.c > create mode 100644 gcc/testsuite/gcc.target/powerpc/pr103743_1.c > > diff --git a/gcc/config/rs6000/rs6000-protos.h b/gcc/config/rs6000/rs6000-protos.h > index 3ea01023609..bc7f6ff64ef 100644 > --- a/gcc/config/rs6000/rs6000-protos.h > +++ b/gcc/config/rs6000/rs6000-protos.h > @@ -35,6 +35,7 @@ extern bool xxspltib_constant_p (rtx, machine_mode, int *, int *); > extern int vspltis_shifted (rtx); > extern HOST_WIDE_INT const_vector_elt_as_int (rtx, unsigned int); > extern bool macho_lo_sum_memory_operand (rtx, machine_mode); > +extern int rotate_from_leading_zeros_const (unsigned HOST_WIDE_INT, int); > extern int num_insns_constant (rtx, machine_mode); > extern int small_data_operand (rtx, machine_mode); > extern bool mem_operand_gpr (rtx, machine_mode); > diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc > index 3ff16b8ae04..9c0996603d0 100644 > --- a/gcc/config/rs6000/rs6000.cc > +++ b/gcc/config/rs6000/rs6000.cc > @@ -14861,6 +14861,35 @@ rs6000_reverse_condition (machine_mode mode, enum rtx_code code) > return reverse_condition (code); > } > > +/* Check if C can be rotated from an immediate which contains leading > + zeros at least CLZ. > + > + Return the number by which C can be rotated from the immediate. > + Return -1 if C can not be rotated as from. */ > + > +int > +rotate_from_leading_zeros_const (unsigned HOST_WIDE_INT c, int clz) > +{ > + /* case. 0..0xxx: already at least clz zeros. */ > + int lz = clz_hwi (c); > + if (lz >= clz) > + return 0; > + > + /* case a. 0..0xxx0..0: at least clz zeros. */ > + int tz = ctz_hwi (c); > + if (lz + tz >= clz) > + return tz; > + > + /* xx0..0xx: rotate enough bits firstly, then check case a. */ > + const int rot_bits = HOST_BITS_PER_WIDE_INT - clz + 1; > + unsigned HOST_WIDE_INT rc = (c >> rot_bits) | (c << (clz - 1)); > + tz = ctz_hwi (rc); > + if (clz_hwi (rc) + tz >= clz) > + return tz + rot_bits; > + > + return -1; > +} > + > /* Generate a compare for CODE. Return a brand-new rtx that > represents the result of the compare. */ > > diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md > index 1367a2cb779..603781b29aa 100644 > --- a/gcc/config/rs6000/rs6000.md > +++ b/gcc/config/rs6000/rs6000.md > @@ -7720,6 +7720,59 @@ (define_insn "*movsi_from_df" > "xscvdpsp %x0,%x1" > [(set_attr "type" "fp")]) > > + > +(define_code_iterator eqne [eq ne]) > + > +;; "i == C" ==> "rotl(i,N) == rotl(C,N)" > +(define_insn_and_split "*rotate_on_cmpdi" > + [(set (pc) > + (if_then_else (eqne (match_operand:DI 1 "gpc_reg_operand" "r") > + (match_operand:DI 2 "const_int_operand" "n")) > + (label_ref (match_operand 0 "")) > + (pc)))] > + "TARGET_POWERPC64 && !reload_completed && can_create_pseudo_p () > + && num_insns_constant (operands[2], DImode) > 1 > + && (rotate_from_leading_zeros_const (~UINTVAL (operands[2]), 49) > 0 > + || rotate_from_leading_zeros_const (UINTVAL (operands[2]), 48) > 0)" > + "#" > + "&& 1" > + [(pc)] > +{ > + rtx cnd = XEXP (SET_SRC (single_set (curr_insn)), 0); > + bool ne = GET_CODE (cnd) == NE; > + > + bool sgn = false; > + unsigned HOST_WIDE_INT C = INTVAL (operands[2]); > + int rot = rotate_from_leading_zeros_const (C, 48); > + if (rot < 0) > + { > + sgn = true; > + rot = rotate_from_leading_zeros_const (~C, 49); > + } > + rtx n = GEN_INT (HOST_BITS_PER_WIDE_INT - rot); > + > + /* i' = rotl (i, n) */ > + rtx op0 = gen_reg_rtx (DImode); > + emit_insn (gen_rtx_SET (op0, gen_rtx_ROTATE (DImode, operands[1], n))); > + > + /* C' = rotl (C, n) */ > + rtx op1 = GEN_INT ((C << INTVAL (n)) | (C >> rot)); > + > + /* i' == C' */ > + machine_mode comp_mode = sgn ? CCmode : CCUNSmode; > + rtx cc = gen_reg_rtx (comp_mode); > + emit_insn (gen_rtx_SET (cc, gen_rtx_COMPARE (comp_mode, op0, op1))); > + > + rtx cmp = ne ? gen_rtx_NE (CCmode, cc, const0_rtx) > + : gen_rtx_EQ (CCmode, cc, const0_rtx); > + rtx loc_ref = gen_rtx_LABEL_REF (VOIDmode, operands[0]); > + emit_jump_insn (gen_rtx_SET (pc_rtx, > + gen_rtx_IF_THEN_ELSE (VOIDmode, cmp, > + loc_ref, pc_rtx))); > + DONE; > +} > +) > + > ;; Split a load of a large constant into the appropriate two-insn > ;; sequence. > > @@ -13426,7 +13479,6 @@ (define_expand "@ctr" > ;; rs6000_legitimate_combined_insn prevents combine creating any of > ;; the ctr insns. > > -(define_code_iterator eqne [eq ne]) > (define_code_attr bd [(eq "bdz") (ne "bdnz")]) > (define_code_attr bd_neg [(eq "bdnz") (ne "bdz")]) > > diff --git a/gcc/testsuite/gcc.target/powerpc/pr103743.c b/gcc/testsuite/gcc.target/powerpc/pr103743.c > new file mode 100644 > index 00000000000..e18833685fb > --- /dev/null > +++ b/gcc/testsuite/gcc.target/powerpc/pr103743.c > @@ -0,0 +1,52 @@ > +/* { dg-do compile } */ > +/* { dg-require-effective-target lp64 } */ > +/* { dg-options "-O2" } */ > +/* { dg-final { scan-assembler-times "cmpldi" 10 } } */ > +/* { dg-final { scan-assembler-times "cmpdi" 4 } } */ > +/* { dg-final { scan-assembler-times "rotldi" 14 } } */ > + > +int foo (int a); > + > +int __attribute__ ((noinline)) udi_fun (unsigned long long in) > +{ > + if (in == (0x8642000000000000ULL)) > + return foo (1); > + if (in == (0x7642000000000000ULL)) > + return foo (12); > + if (in == (0x8000000000000000ULL)) > + return foo (32); > + if (in == (0x8000000000000001ULL)) > + return foo (33); > + if (in == (0x8642FFFFFFFFFFFFULL)) > + return foo (46); > + if (in == (0x7642FFFFFFFFFFFFULL)) > + return foo (51); > + if (in == (0x7567000000ULL)) > + return foo (9); > + if (in == (0xFFF8567FFFFFFFFFULL)) > + return foo (19); > + > + return 0; > +} > + > +int __attribute__ ((noinline)) di_fun (long long in) > +{ > + if (in == (0x8642000000000000LL)) > + return foo (1); > + if (in == (0x7642000000000000LL)) > + return foo (12); > + if (in == (0x8000000000000000LL)) > + return foo (32); > + if (in == (0x8000000000000001LL)) > + return foo (33); > + if (in == (0x8642FFFFFFFFFFFFLL)) > + return foo (46); > + if (in == (0x7642FFFFFFFFFFFFLL)) > + return foo (51); > + if (in == (0x7567000000LL)) > + return foo (9); > + if (in == (0xFFF8567FFFFFFFFFLL)) > + return foo (19); > + > + return 0; > +} > diff --git a/gcc/testsuite/gcc.target/powerpc/pr103743_1.c b/gcc/testsuite/gcc.target/powerpc/pr103743_1.c > new file mode 100644 > index 00000000000..2c08c56714a > --- /dev/null > +++ b/gcc/testsuite/gcc.target/powerpc/pr103743_1.c > @@ -0,0 +1,95 @@ > +/* { dg-do run } */ > +/* { dg-options "-O2 -std=c99" } */ > + > +int > +foo (int a) > +{ > + return a + 6; > +} > + > +int __attribute__ ((noinline)) udi_fun (unsigned long long in) > +{ > + if (in == (0x8642000000000000ULL)) > + return foo (1); > + if (in == (0x7642000000000000ULL)) > + return foo (12); > + if (in == (0x8000000000000000ULL)) > + return foo (32); > + if (in == (0x8000000000000001ULL)) > + return foo (33); > + if (in == (0x8642FFFFFFFFFFFFULL)) > + return foo (46); > + if (in == (0x7642FFFFFFFFFFFFULL)) > + return foo (51); > + if (in == (0x7567000000ULL)) > + return foo (9); > + if (in == (0xFFF8567FFFFFFFFFULL)) > + return foo (19); > + > + return 0; > +} > + > +int __attribute__ ((noinline)) di_fun (long long in) > +{ > + if (in == (0x8642000000000000LL)) > + return foo (1); > + if (in == (0x7642000000000000LL)) > + return foo (12); > + if (in == (0x8000000000000000LL)) > + return foo (32); > + if (in == (0x8000000000000001LL)) > + return foo (33); > + if (in == (0x8642FFFFFFFFFFFFLL)) > + return foo (46); > + if (in == (0x7642FFFFFFFFFFFFLL)) > + return foo (51); > + return 0; > +} > + > +int > +main () > +{ > + int e = 0; > + if (udi_fun (6) != 0) > + e++; > + if (udi_fun (0x8642000000000000ULL) != foo (1)) > + e++; > + if (udi_fun (0x7642000000000000ULL) != foo (12)) > + e++; > + if (udi_fun (0x8000000000000000ULL) != foo (32)) > + e++; > + if (udi_fun (0x8000000000000001ULL) != foo (33)) > + e++; > + if (udi_fun (0x8642FFFFFFFFFFFFULL) != foo (46)) > + e++; > + if (udi_fun (0x7642FFFFFFFFFFFFULL) != foo (51)) > + e++; > + if (udi_fun (0x7567000000ULL) != foo (9)) > + e++; > + if (udi_fun (0xFFF8567FFFFFFFFFULL) != foo (19)) > + e++; > + > + if (di_fun (6) != 0) > + e++; > + if (di_fun (0x8642000000000000LL) != foo (1)) > + e++; > + if (di_fun (0x7642000000000000LL) != foo (12)) > + e++; > + if (di_fun (0x8000000000000000LL) != foo (32)) > + e++; > + if (di_fun (0x8000000000000001LL) != foo (33)) > + e++; > + if (di_fun (0x8642FFFFFFFFFFFFLL) != foo (46)) > + e++; > + if (di_fun (0x7642FFFFFFFFFFFFLL) != foo (51)) > + e++; > + if (udi_fun (0x7567000000LL) != foo (9)) > + e++; > + if (udi_fun (0xFFF8567FFFFFFFFFLL) != foo (19)) > + e++; > + > + if (e) > + __builtin_abort (); > + return 0; > +} > +