From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0a-001b2d01.pphosted.com (mx0a-001b2d01.pphosted.com [148.163.156.1]) by sourceware.org (Postfix) with ESMTPS id C64F03857403 for ; Thu, 15 Jul 2021 00:17:30 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C64F03857403 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.43/8.16.0.43) with SMTP id 16F06Olv142413; Wed, 14 Jul 2021 20:17:29 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 39ssjy3ya1-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 14 Jul 2021 20:17:29 -0400 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.43/8.16.0.43) with SMTP id 16F08B4N145801; Wed, 14 Jul 2021 20:17:29 -0400 Received: from ppma01dal.us.ibm.com (83.d6.3fa9.ip4.static.sl-reverse.com [169.63.214.131]) by mx0a-001b2d01.pphosted.com with ESMTP id 39ssjy3y9u-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 14 Jul 2021 20:17:29 -0400 Received: from pps.filterd (ppma01dal.us.ibm.com [127.0.0.1]) by ppma01dal.us.ibm.com (8.16.1.2/8.16.1.2) with SMTP id 16F0DLds014653; Thu, 15 Jul 2021 00:17:28 GMT Received: from b01cxnp23032.gho.pok.ibm.com (b01cxnp23032.gho.pok.ibm.com [9.57.198.27]) by ppma01dal.us.ibm.com with ESMTP id 39q36dnfdc-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Thu, 15 Jul 2021 00:17:28 +0000 Received: from b01ledav004.gho.pok.ibm.com (b01ledav004.gho.pok.ibm.com [9.57.199.109]) by b01cxnp23032.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 16F0HRLW53739988 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Thu, 15 Jul 2021 00:17:27 GMT Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 3BB80112069; Thu, 15 Jul 2021 00:17:27 +0000 (GMT) Received: from b01ledav004.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id CCDC5112062; Thu, 15 Jul 2021 00:17:26 +0000 (GMT) Received: from ltc.linux.ibm.com (unknown [9.10.229.42]) by b01ledav004.gho.pok.ibm.com (Postfix) with ESMTP; Thu, 15 Jul 2021 00:17:26 +0000 (GMT) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Thu, 15 Jul 2021 08:17:26 +0800 From: guojiufu To: gcc-patches@gcc.gnu.org, amker.cheng@gmail.com, rguenther@suse.de Cc: wschmidt@linux.ibm.com, segher@kernel.crashing.org, dje.gcc@gmail.com, jlaw@tachyum.com Subject: Re: [PATCH v2] Analyze niter for until-wrap condition [PR101145] In-Reply-To: <20210707124720.16330-1-guojiufu@linux.ibm.com> References: <20210707124720.16330-1-guojiufu@linux.ibm.com> Message-ID: <569d241bba92a6b29be787bb61990740@imap.linux.ibm.com> X-Sender: guojiufu@linux.ibm.com User-Agent: Roundcube Webmail/1.1.12 X-TM-AS-GCONF: 00 X-Proofpoint-GUID: SRTkjo9LYhZKOOGBAb-4e98OoNZ8ke-D X-Proofpoint-ORIG-GUID: 89trVr8KnMI5fxe2SJh8_2oGQcw5uXGt X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391, 18.0.790 definitions=2021-07-14_14:2021-07-14, 2021-07-14 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 suspectscore=0 bulkscore=0 malwarescore=0 adultscore=0 spamscore=0 impostorscore=0 clxscore=1015 lowpriorityscore=0 priorityscore=1501 mlxscore=0 phishscore=0 mlxlogscore=999 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2104190000 definitions=main-2107140149 X-Spam-Status: No, score=-11.3 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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: Thu, 15 Jul 2021 00:17:33 -0000 Hi, I would like to have an early ping on this with more mail addresses. BR, Jiufu. On 2021-07-07 20:47, Jiufu Guo wrote: > Changes since v1: > * Update assumptions for niter, add more test cases check > * Use widest_int/wide_int instead mpz to do +-/ > * Move some early check for quick return > > For code like: > unsigned foo(unsigned val, unsigned start) > { > unsigned cnt = 0; > for (unsigned i = start; i > val; ++i) > cnt++; > return cnt; > } > > The number of iterations should be about UINT_MAX - start. > > There is function adjust_cond_for_loop_until_wrap which > handles similar work for const bases. > Like adjust_cond_for_loop_until_wrap, this patch enhance > function number_of_iterations_cond/number_of_iterations_lt > to analyze number of iterations for this kind of loop. > > Bootstrap and regtest pass on powerpc64le, x86_64 and aarch64. > Is this ok for trunk? > > gcc/ChangeLog: > > 2021-07-07 Jiufu Guo > > PR tree-optimization/101145 > * tree-ssa-loop-niter.c (number_of_iterations_until_wrap): > New function. > (number_of_iterations_lt): Invoke above function. > (adjust_cond_for_loop_until_wrap): > Merge to number_of_iterations_until_wrap. > (number_of_iterations_cond): Update invokes for > adjust_cond_for_loop_until_wrap and number_of_iterations_lt. > > gcc/testsuite/ChangeLog: > > 2021-07-07 Jiufu Guo > > PR tree-optimization/101145 > * gcc.dg/vect/pr101145.c: New test. > * gcc.dg/vect/pr101145.inc: New test. > * gcc.dg/vect/pr101145_1.c: New test. > * gcc.dg/vect/pr101145_2.c: New test. > * gcc.dg/vect/pr101145_3.c: New test. > * gcc.dg/vect/pr101145inf.c: New test. > * gcc.dg/vect/pr101145inf.inc: New test. > * gcc.dg/vect/pr101145inf_1.c: New test. > --- > gcc/testsuite/gcc.dg/vect/pr101145.c | 187 ++++++++++++++++++++++ > gcc/testsuite/gcc.dg/vect/pr101145.inc | 63 ++++++++ > gcc/testsuite/gcc.dg/vect/pr101145_1.c | 15 ++ > gcc/testsuite/gcc.dg/vect/pr101145_2.c | 15 ++ > gcc/testsuite/gcc.dg/vect/pr101145_3.c | 15 ++ > gcc/testsuite/gcc.dg/vect/pr101145inf.c | 25 +++ > gcc/testsuite/gcc.dg/vect/pr101145inf.inc | 28 ++++ > gcc/testsuite/gcc.dg/vect/pr101145inf_1.c | 23 +++ > gcc/tree-ssa-loop-niter.c | 157 ++++++++++-------- > 9 files changed, 463 insertions(+), 65 deletions(-) > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145.c > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145.inc > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145_1.c > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145_2.c > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145_3.c > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145inf.c > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145inf.inc > create mode 100644 gcc/testsuite/gcc.dg/vect/pr101145inf_1.c > > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145.c > b/gcc/testsuite/gcc.dg/vect/pr101145.c > new file mode 100644 > index 00000000000..74031b031cf > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145.c > @@ -0,0 +1,187 @@ > +/* { dg-require-effective-target vect_int } */ > +/* { dg-options "-O3 -fdump-tree-vect-details" } */ > +#include > + > +unsigned __attribute__ ((noinline)) > +foo (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned n) > +{ > + while (n < ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +foo_1 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned) > +{ > + while (UINT_MAX - 64 < ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +foo_2 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned > n) > +{ > + l = UINT_MAX - 32; > + while (n < ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +foo_3 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned > n) > +{ > + while (n <= ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +foo_4 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned > n) > +{ // infininate > + while (0 <= ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +foo_5 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned > n) > +{ > + //no loop > + l = UINT_MAX; > + while (n < ++l) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +bar (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned n) > +{ > + while (--l < n) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +bar_1 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned) > +{ > + while (--l < 64) > + *a++ = *b++ + 1; > + return l; > +} > + > +unsigned __attribute__ ((noinline)) > +bar_2 (int *__restrict__ a, int *__restrict__ b, unsigned l, unsigned > n) > +{ > + l = 32; > + while (--l < n) > + *a++ = *b++ + 1; > + return l; > +} > + > + > +int a[3200], b[3200]; > +int fail; > + > +int > +main () > +{ > + unsigned l, n; > + unsigned res; > + /* l > n*/ > + n = UINT_MAX - 64; > + l = n + 32; > + res = foo (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n; > + res = foo (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n - 1; > + res = foo (a, b, l, n); > + if (res != l + 1) > + fail++; > + > + l = n - 32; > + res = foo (a, b, l, n); > + if (res != l + 1) > + fail++; > + > + l = UINT_MAX; > + res = foo (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n + 32; > + res = foo_1 (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n + 32; > + res = foo_2 (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n; > + res = foo_3 (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n - 1; > + res = foo_3 (a, b, l, n); > + if (res != 0) > + fail++; > + > + l = n - 2; > + res = foo_3 (a, b, l, n); > + if (res != l + 1) > + fail++; > + > + res = foo_5 (a, b, l, n); > + if (res != 0) > + fail++; > + > + n = 64; > + l = n - 32; > + res = bar (a, b, l, n); > + res++; > + if (res != 0) > + fail++; > + > + l = n; > + res = bar (a, b, l, n); > + res++; > + if (res != 0) > + fail++; > + > + l = n + 1; > + res = bar (a, b, l, n); > + res++; > + if (res != l) > + fail++; > + > + l = 0; > + res = bar (a, b, l, n); > + res++; > + if (res != l) > + fail++; > + > + l = 32; > + res = bar_1 (a, b, l, n); > + res++; > + if (res != 0) > + fail++; > + > + res = bar_1 (a, b, l, n); > + res++; > + if (res != 0) > + fail++; > + > + if (fail) > + __builtin_abort (); > + return 0; > +} > + > +/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 7 "vect" } } > */ > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145.inc > b/gcc/testsuite/gcc.dg/vect/pr101145.inc > new file mode 100644 > index 00000000000..6eed3fa8aca > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145.inc > @@ -0,0 +1,63 @@ > +TYPE __attribute__ ((noinline)) > +foo_sign (int *__restrict__ a, int *__restrict__ b, TYPE l, TYPE n) > +{ > + for (l = L_BASE; n < l; l += C) > + *a++ = *b++ + 1; > + return l; > +} > + > +TYPE __attribute__ ((noinline)) > +bar_sign (int *__restrict__ a, int *__restrict__ b, TYPE l, TYPE n) > +{ > + for (l = L_BASE_DOWN; l < n; l -= C) > + *a++ = *b++ + 1; > + return l; > +} > + > +int __attribute__ ((noinline)) neq (int a, int b) { return a != b; } > + > +int a[1000], b[1000]; > +int fail; > + > +int > +main () > +{ > + TYPE res; > + TYPE l; > + TYPE n; > + n = N_BASE; > + l = n - C; > + res = foo_sign (a, b, l, n); > + if (res != l) > + fail++; > + > + l = n; > + res = foo_sign (a, b, l, n); > + if (res != l) > + fail++; > + > + l = n + C; > + res = foo_sign (a, b, l, n); > + if (neq ((res - MIN) / C, 0)) > + fail++; > + > + n = N_BASE_DOWN; > + l = n - C; > + res = bar_sign (a, b, l, n); > + if (neq ((MAX - res) / C, 0)) > + fail++; > + > + l = n; > + res = bar_sign (a, b, l, n); > + if (res != l) > + fail++; > + > + l = n + C; > + res = bar_sign (a, b, l, n); > + if (res != l) > + fail++; > + > + if (fail) > + __builtin_abort (); > + return 0; > +} > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145_1.c > b/gcc/testsuite/gcc.dg/vect/pr101145_1.c > new file mode 100644 > index 00000000000..94f6b99b893 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145_1.c > @@ -0,0 +1,15 @@ > +/* { dg-require-effective-target vect_int } */ > +/* { dg-options "-O3 -fdump-tree-vect-details" } */ > +#define TYPE signed char > +#define MIN -128 > +#define MAX 127 > +#define N_BASE (MAX - 32) > +#define N_BASE_DOWN (MIN + 32) > + > +#define C 3 > +#define L_BASE l > +#define L_BASE_DOWN l > + > +#include "pr101145.inc" > + > +/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 2 "vect" } } > */ > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145_2.c > b/gcc/testsuite/gcc.dg/vect/pr101145_2.c > new file mode 100644 > index 00000000000..d3cfc9e01e1 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145_2.c > @@ -0,0 +1,15 @@ > +/* { dg-require-effective-target vect_int } */ > +/* { dg-options "-O3 -fdump-tree-vect-details" } */ > +#define TYPE unsigned char > +#define MIN 0 > +#define MAX 255 > +#define N_BASE (MAX - 32 + 1) > +#define N_BASE_DOWN (MIN + 32) > + > +#define C 2 > +#define L_BASE l > +#define L_BASE_DOWN l > + > +#include "pr101145.inc" > + > +/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 2 "vect" } } > */ > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145_3.c > b/gcc/testsuite/gcc.dg/vect/pr101145_3.c > new file mode 100644 > index 00000000000..9d5863726a5 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145_3.c > @@ -0,0 +1,15 @@ > +/* { dg-require-effective-target vect_int } */ > +/* { dg-options "-O3 -fdump-tree-vect-details" } */ > +#define TYPE int * > +#define MIN ((TYPE)0) > +#define MAX ((TYPE)((long long)-1)) > +#define N_BASE (MIN - 32) > +#define N_BASE_DOWN (MIN + 32) > + > +#define C 1 > +#define L_BASE l > +#define L_BASE_DOWN l > + > +#include "pr101145.inc" > + > +/* { dg-final { scan-tree-dump-times "vectorized 1 loops" 2 "vect" } } > */ > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145inf.c > b/gcc/testsuite/gcc.dg/vect/pr101145inf.c > new file mode 100644 > index 00000000000..ed49f5670b5 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145inf.c > @@ -0,0 +1,25 @@ > +/* { dg-do run { target *-*-linux* *-*-gnu* *-*-uclinux* } } */ > +/* { dg-options "-O3" } */ > +#include > +#include "pr101145inf.inc" > + > +__attribute__ ((noinline)) > +unsigned foo(unsigned val, unsigned start) > +{ > + unsigned cnt = 0; > + for (unsigned i = start; val <= i; i+=16) > + cnt++; > + return cnt; > +} > + > +void test_finite () > +{ > + unsigned n = foo (16, UINT_MAX - 32); > + if (n != 3) > + __builtin_abort (); > +} > + > +void test_infinite () > +{ > + foo (15, UINT_MAX - 32); > +} > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145inf.inc > b/gcc/testsuite/gcc.dg/vect/pr101145inf.inc > new file mode 100644 > index 00000000000..4aa3d049187 > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145inf.inc > @@ -0,0 +1,28 @@ > +#include > +#include > +#include > + > +void test_finite (); > +void test_infinite (); > + > +void do_exit (int i) > +{ > + exit (0); > +} > + > +int main(void) > +{ > + test_finite (); > + struct sigaction s; > + sigemptyset (&s.sa_mask); > + s.sa_handler = do_exit; > + s.sa_flags = 0; > + sigaction (SIGALRM, &s, NULL); > + alarm (1); > + > + test_infinite (); > + > + __builtin_abort (); > + return 1; > +} > + > diff --git a/gcc/testsuite/gcc.dg/vect/pr101145inf_1.c > b/gcc/testsuite/gcc.dg/vect/pr101145inf_1.c > new file mode 100644 > index 00000000000..4ee3e31c7fe > --- /dev/null > +++ b/gcc/testsuite/gcc.dg/vect/pr101145inf_1.c > @@ -0,0 +1,23 @@ > +/* { dg-do run { target *-*-linux* *-*-gnu* *-*-uclinux* } } */ > +/* { dg-options "-O3" } */ > +#include > +#include "pr101145inf.inc" > + > +__attribute__ ((noinline)) > +unsigned foo(unsigned val, unsigned start) > +{ > + unsigned cnt = 0; > + for (unsigned i = start; i < val; i-=16) > + cnt++; > + return cnt; > +} > + > +void test_finite () > +{ > + foo (UINT_MAX - 15, 32); > +} > + > +void test_infinite () > +{ > + foo (UINT_MAX - 14, 32); > +} > diff --git a/gcc/tree-ssa-loop-niter.c b/gcc/tree-ssa-loop-niter.c > index b5add827018..85c179be68d 100644 > --- a/gcc/tree-ssa-loop-niter.c > +++ b/gcc/tree-ssa-loop-niter.c > @@ -1473,6 +1473,93 @@ assert_loop_rolls_lt (tree type, affine_iv > *iv0, affine_iv *iv1, > } > } > > +/* Determines number of iterations of loop whose ending condition > + is IV0 < IV1 which likes: {base, -C} < n, or n < {base, C}. > + The number of iterations is stored to NITER. */ > + > +static bool > +number_of_iterations_until_wrap (class loop *, tree type, affine_iv > *iv0, > + affine_iv *iv1, class tree_niter_desc *niter) > +{ > + tree niter_type = unsigned_type_for (type); > + tree step, num, assumptions, may_be_zero; > + wide_int high, low, max, min; > + > + may_be_zero = fold_build2 (LE_EXPR, boolean_type_node, iv1->base, > iv0->base); > + if (integer_onep (may_be_zero)) > + return false; > + > + int prec = TYPE_PRECISION (type); > + signop sgn = TYPE_SIGN (type); > + min = wi::min_value (prec, sgn); > + max = wi::max_value (prec, sgn); > + > + /* n < {base, C}. */ > + if (integer_zerop (iv0->step) && !tree_int_cst_sign_bit (iv1->step)) > + { > + step = iv1->step; > + /* MIN + C - 1 <= n. */ > + tree last = wide_int_to_tree (type, min + wi::to_wide (step) - > 1); > + assumptions = fold_build2 (LE_EXPR, boolean_type_node, last, > iv0->base); > + if (integer_zerop (assumptions)) > + return false; > + > + num = fold_build2 (MINUS_EXPR, niter_type, wide_int_to_tree > (type, max), > + iv1->base); > + high = max; > + if (TREE_CODE (iv1->base) == INTEGER_CST) > + low = wi::to_wide (iv1->base) - 1; > + else if (TREE_CODE (iv0->base) == INTEGER_CST) > + low = wi::to_wide (iv0->base); > + else > + low = min; > + } > + /* {base, -C} < n. */ > + else if (tree_int_cst_sign_bit (iv0->step) && integer_zerop > (iv1->step)) > + { > + step = fold_build1 (NEGATE_EXPR, TREE_TYPE (iv0->step), > iv0->step); > + /* MAX - C + 1 >= n. */ > + tree last = wide_int_to_tree (type, max - wi::to_wide (step) + > 1); > + assumptions = fold_build2 (GE_EXPR, boolean_type_node, last, > iv1->base); > + if (integer_zerop (assumptions)) > + return false; > + > + num = fold_build2 (MINUS_EXPR, niter_type, iv0->base, > + wide_int_to_tree (type, min)); > + low = min; > + if (TREE_CODE (iv0->base) == INTEGER_CST) > + high = wi::to_wide (iv0->base) + 1; > + else if (TREE_CODE (iv1->base) == INTEGER_CST) > + high = wi::to_wide (iv1->base); > + else > + high = max; > + } > + else > + return false; > + > + /* (delta + step - 1) / step */ > + step = fold_convert (niter_type, step); > + num = fold_convert (niter_type, num); > + num = fold_build2 (PLUS_EXPR, niter_type, num, step); > + niter->niter = fold_build2 (FLOOR_DIV_EXPR, niter_type, num, step); > + > + widest_int delta, s; > + delta = widest_int::from (high, sgn) - widest_int::from (low, sgn); > + s = wi::to_widest (step); > + delta = delta + s - 1; > + niter->max = wi::udiv_floor (delta, s); > + > + niter->may_be_zero = may_be_zero; > + > + if (!integer_nonzerop (assumptions)) > + niter->assumptions = fold_build2 (TRUTH_AND_EXPR, > boolean_type_node, > + niter->assumptions, assumptions); > + > + niter->control.no_overflow = false; > + > + return true; > +} > + > /* Determines number of iterations of loop whose ending condition > is IV0 < IV1. TYPE is the type of the iv. The number of > iterations is stored to NITER. BNDS bounds the difference > @@ -1501,6 +1588,11 @@ number_of_iterations_lt (class loop *loop, tree > type, affine_iv *iv0, > niter->bound = iv0->base; > } > > + /* {base, -C} < n, or n < {base, C} */ > + if (tree_int_cst_sign_bit (iv0->step) > + || (!integer_zerop (iv1->step) && !tree_int_cst_sign_bit > (iv1->step))) > + return number_of_iterations_until_wrap (loop, type, iv0, iv1, > niter); > + > delta = fold_build2 (MINUS_EXPR, niter_type, > fold_convert (niter_type, iv1->base), > fold_convert (niter_type, iv0->base)); > @@ -1665,62 +1757,6 @@ dump_affine_iv (FILE *file, affine_iv *iv) > } > } > > -/* Given exit condition IV0 CODE IV1 in TYPE, this function adjusts > - the condition for loop-until-wrap cases. For example: > - (unsigned){8, -1}_loop < 10 => {0, 1} != 9 > - 10 < (unsigned){0, max - 7}_loop => {0, 1} != 8 > - Return true if condition is successfully adjusted. */ > - > -static bool > -adjust_cond_for_loop_until_wrap (tree type, affine_iv *iv0, tree_code > *code, > - affine_iv *iv1) > -{ > - /* Only support simple cases for the moment. */ > - if (TREE_CODE (iv0->base) != INTEGER_CST > - || TREE_CODE (iv1->base) != INTEGER_CST) > - return false; > - > - tree niter_type = unsigned_type_for (type), high, low; > - /* Case: i-- < 10. */ > - if (integer_zerop (iv1->step)) > - { > - /* TODO: Should handle case in which abs(step) != 1. */ > - if (!integer_minus_onep (iv0->step)) > - return false; > - /* Give up on infinite loop. */ > - if (*code == LE_EXPR > - && tree_int_cst_equal (iv1->base, TYPE_MAX_VALUE (type))) > - return false; > - high = fold_build2 (PLUS_EXPR, niter_type, > - fold_convert (niter_type, iv0->base), > - build_int_cst (niter_type, 1)); > - low = fold_convert (niter_type, TYPE_MIN_VALUE (type)); > - } > - else if (integer_zerop (iv0->step)) > - { > - /* TODO: Should handle case in which abs(step) != 1. */ > - if (!integer_onep (iv1->step)) > - return false; > - /* Give up on infinite loop. */ > - if (*code == LE_EXPR > - && tree_int_cst_equal (iv0->base, TYPE_MIN_VALUE (type))) > - return false; > - high = fold_convert (niter_type, TYPE_MAX_VALUE (type)); > - low = fold_build2 (MINUS_EXPR, niter_type, > - fold_convert (niter_type, iv1->base), > - build_int_cst (niter_type, 1)); > - } > - else > - gcc_unreachable (); > - > - iv0->base = low; > - iv0->step = fold_convert (niter_type, integer_one_node); > - iv1->base = high; > - iv1->step = build_int_cst (niter_type, 0); > - *code = NE_EXPR; > - return true; > -} > - > /* Determine the number of iterations according to condition (for > staying > inside loop) which compares two induction variables using > comparison > operator CODE. The induction variable on left side of the > comparison > @@ -1855,15 +1891,6 @@ number_of_iterations_cond (class loop *loop, > return true; > } > > - /* Handle special case loops: while (i-- < 10) and while (10 < i++) > by > - adjusting iv0, iv1 and code. */ > - if (code != NE_EXPR > - && (tree_int_cst_sign_bit (iv0->step) > - || (!integer_zerop (iv1->step) > - && !tree_int_cst_sign_bit (iv1->step))) > - && !adjust_cond_for_loop_until_wrap (type, iv0, &code, iv1)) > - return false; > - > /* OK, now we know we have a senseful loop. Handle several cases, > depending > on what comparison operator is used. */ > bound_difference (loop, iv1->base, iv0->base, &bnds);