From patchwork Mon Oct 10 11:03:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Richard Biener X-Patchwork-Id: 58579 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 147913858011 for ; Mon, 10 Oct 2022 11:04:43 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 147913858011 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1665399883; bh=PdFevge1rCtUCNsCsByyMnGqHQd6ddeRt9l+Ohv6Bn0=; h=Date:To:Subject:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=MCsCp4T2489NeLBEDpJ9gg/d+PjGy4TYnvMxOGR3PmrM6UkeNNmWTgwK3CK5p6WVe k8UHXraies9zYoiNMjfOyej8SXuAsfDLtdyesv8I3ZjOTf36MsEW0SvqG/aMDUnO80 ZLJIxMliamHu44y0iuKdrrd6olC/8FvdSzeOOE8Y= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from smtp-out2.suse.de (smtp-out2.suse.de [195.135.220.29]) by sourceware.org (Postfix) with ESMTPS id 4EE7638582A7 for ; Mon, 10 Oct 2022 11:03:41 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 4EE7638582A7 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 2C74C1F8C9; Mon, 10 Oct 2022 11:03:40 +0000 (UTC) Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id E9E2513479; Mon, 10 Oct 2022 11:03:39 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id 447pNwv8Q2PwOgAAMHmgww (envelope-from ); Mon, 10 Oct 2022 11:03:39 +0000 Date: Mon, 10 Oct 2022 13:03:39 +0200 (CEST) To: gcc-patches@gcc.gnu.org Subject: [PATCH][RFT] Vectorization of first-order recurrences MIME-Version: 1.0 Message-Id: <20221010110339.E9E2513479@imap2.suse-dmz.suse.de> X-Spam-Status: No, score=-11.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, SPF_HELO_NONE, SPF_PASS, TXREP 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-Patchwork-Original-From: Richard Biener via Gcc-patches From: Richard Biener Reply-To: Richard Biener Cc: richard.sandiford@arm.com, juzhe.zhong@rivai.ai, ams@codesourcery.com Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" The following picks up the prototype by Ju-Zhe Zhong for vectorizing first order recurrences. That solves two TSVC missed optimization PRs. There's a new scalar cycle def kind, vect_first_order_recurrence and it's handling of the backedge value vectorization is complicated by the fact that the vectorized value isn't the PHI but instead a (series of) permute(s) shifting in the recurring value from the previous iteration. I've implemented this by creating both the single vectorized PHI and the series of permutes when vectorizing the scalar PHI but leave the backedge values in both unassigned. The backedge values are (for the testcases) computed by a load which is also the place after which the permutes are inserted. That placement also restricts the cases we can handle (without resorting to code motion). I added both costing and SLP handling though SLP handling is restricted to the case where a single vectorized PHI is enough. Missing is epilogue handling - while prologue peeling would be handled transparently by adjusting iv_phi_p the epilogue case doesn't work with just inserting a scalar LC PHI since that a) keeps the scalar load live and b) that loads is the wrong one, it has to be the last, much like when we'd vectorize the LC PHI as live operation. Unfortunately LIVE compute/analysis happens too early before we decide on peeling. When using fully masked loop vectorization the vect-recurr-6.c works as expected though. I have tested this on x86_64 for now, but since epilogue handling is missing there's probably no practical cases. My prototype WHILE_ULT AVX512 patch can handle vect-recurr-6.c just fine but I didn't feel like running SPEC within SDE nor is the WHILE_ULT patch complete enough. Builds of SPEC 2k7 with fully masked loops succeed (minus three cases of PR107096, caused by my WHILE_ULT prototype). Bootstrapped and tested on x86_64-unknown-linux-gnu. Testing with SVE, GCN or RVV appreciated, ideas how to cleanly handle epilogues welcome. Thanks, Richard. PR tree-optimization/99409 PR tree-optimization/99394 * tree-vectorizer.h (vect_def_type::vect_first_order_recurrence): Add. (stmt_vec_info_type::recurr_info_type): Likewise. (vectorizable_recurr): New function. * tree-vect-loop.cc (vect_phi_first_order_recurrence_p): New function. (vect_analyze_scalar_cycles_1): Look for first order recurrences. (vect_analyze_loop_operations): Handle them. (vect_transform_loop): Likewise. (vectorizable_recurr): New function. (maybe_set_vectorized_backedge_value): Handle the backedge value setting in the first order recurrence PHI and the permutes. * tree-vect-stmts.cc (vect_analyze_stmt): Handle first order recurrences. (vect_transform_stmt): Likewise. (vect_is_simple_use): Likewise. (vect_is_simple_use): Likewise. * tree-vect-slp.cc (vect_get_and_check_slp_defs): Likewise. (vect_build_slp_tree_2): Likewise. (vect_schedule_scc): Handle the backedge value setting in the first order recurrence PHI and the permutes. * gcc.dg/vect/vect-recurr-1.c: New testcase. * gcc.dg/vect/vect-recurr-2.c: Likewise. * gcc.dg/vect/vect-recurr-3.c: Likewise. * gcc.dg/vect/vect-recurr-4.c: Likewise. * gcc.dg/vect/vect-recurr-5.c: Likewise. * gcc.dg/vect/vect-recurr-6.c: Likewise. * gcc.dg/vect/tsvc/vect-tsvc-s252.c: Un-XFAIL. * gcc.dg/vect/tsvc/vect-tsvc-s254.c: Likewise. * gcc.dg/vect/tsvc/vect-tsvc-s291.c: Likewise. Co-authored-by: Ju-Zhe Zhong --- .../gcc.dg/vect/tsvc/vect-tsvc-s252.c | 2 +- .../gcc.dg/vect/tsvc/vect-tsvc-s254.c | 2 +- .../gcc.dg/vect/tsvc/vect-tsvc-s291.c | 2 +- gcc/testsuite/gcc.dg/vect/vect-recurr-1.c | 38 +++ gcc/testsuite/gcc.dg/vect/vect-recurr-2.c | 39 +++ gcc/testsuite/gcc.dg/vect/vect-recurr-3.c | 39 +++ gcc/testsuite/gcc.dg/vect/vect-recurr-4.c | 42 +++ gcc/testsuite/gcc.dg/vect/vect-recurr-5.c | 43 +++ gcc/testsuite/gcc.dg/vect/vect-recurr-6.c | 39 +++ gcc/tree-vect-loop.cc | 286 ++++++++++++++++-- gcc/tree-vect-slp.cc | 38 ++- gcc/tree-vect-stmts.cc | 17 +- gcc/tree-vectorizer.h | 4 + 13 files changed, 563 insertions(+), 28 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-1.c create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-2.c create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-3.c create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-4.c create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-5.c create mode 100644 gcc/testsuite/gcc.dg/vect/vect-recurr-6.c diff --git a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s252.c b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s252.c index f1302b60ae5..83eaa7a8ff5 100644 --- a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s252.c +++ b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s252.c @@ -40,4 +40,4 @@ int main (int argc, char **argv) return 0; } -/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { xfail *-*-* } } } */ +/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s254.c b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s254.c index bdc8a01e2a5..06e9b0a849d 100644 --- a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s254.c +++ b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s254.c @@ -39,4 +39,4 @@ int main (int argc, char **argv) return 0; } -/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { xfail *-*-* } } } */ +/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s291.c b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s291.c index 0b474c2e81a..91cdc121095 100644 --- a/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s291.c +++ b/gcc/testsuite/gcc.dg/vect/tsvc/vect-tsvc-s291.c @@ -39,4 +39,4 @@ int main (int argc, char **argv) return 0; } -/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { xfail *-*-* } } } */ +/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-1.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-1.c new file mode 100644 index 00000000000..6eb59fdf854 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-1.c @@ -0,0 +1,38 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, int * __restrict__ b, int * __restrict__ c) +{ + int t = *c; + for (int i = 0; i < 64; ++i) + { + b[i] = a[i] - t; + t = a[i]; + } +} + +int a[64], b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c); + for (int i = 1; i < 64; ++i) + if (b[i] != a[i] - a[i-1]) + abort (); + if (b[0] != -7) + abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-2.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-2.c new file mode 100644 index 00000000000..97efaaa38bc --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-2.c @@ -0,0 +1,39 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, short * __restrict__ b, int * __restrict__ c) +{ + int t = *c; + for (int i = 0; i < 64; ++i) + { + b[i] = a[i] - t; + t = a[i]; + } +} + +int a[64]; +short b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c); + for (int i = 1; i < 64; ++i) + if (b[i] != a[i] - a[i-1]) + abort (); + if (b[0] != -7) + abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-3.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-3.c new file mode 100644 index 00000000000..621a5d8a257 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-3.c @@ -0,0 +1,39 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, signed char * __restrict__ b, int * __restrict__ c) +{ + int t = *c; + for (int i = 0; i < 64; ++i) + { + b[i] = a[i] - t; + t = a[i]; + } +} + +int a[64]; +signed char b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c); + for (int i = 1; i < 64; ++i) + if (b[i] != a[i] - a[i-1]) + abort (); + if (b[0] != -7) + abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-4.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-4.c new file mode 100644 index 00000000000..f6dbc494a62 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-4.c @@ -0,0 +1,42 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, int * __restrict__ b, int * __restrict__ c) +{ + int t1 = *c; + int t2 = *c; + for (int i = 0; i < 64; i+=2) + { + b[i] = a[i] - t1; + t1 = a[i]; + b[i+1] = a[i+1] - t2; + t2 = a[i+1]; + } +} + +int a[64], b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c); + for (int i = 2; i < 64; i+=2) + if (b[i] != a[i] - a[i-2] + || b[i+1] != a[i+1] - a[i-1]) + abort (); + if (b[0] != -7 || b[1] != -6) + abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-5.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-5.c new file mode 100644 index 00000000000..19c56df9e83 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-5.c @@ -0,0 +1,43 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, short * __restrict__ b, int * __restrict__ c) +{ + int t1 = *c; + int t2 = *c; + for (int i = 0; i < 64; i+=2) + { + b[i] = a[i] - t1; + t1 = a[i]; + b[i+1] = a[i+1] - t2; + t2 = a[i+1]; + } +} + +int a[64]; +short b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c); + for (int i = 2; i < 64; i+=2) + if (b[i] != a[i] - a[i-2] + || b[i+1] != a[i+1] - a[i-1]) + abort (); + if (b[0] != -7 || b[1] != -6) + abort (); + return 0; +} + +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-recurr-6.c b/gcc/testsuite/gcc.dg/vect/vect-recurr-6.c new file mode 100644 index 00000000000..e7712680853 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-recurr-6.c @@ -0,0 +1,39 @@ +/* { dg-do run } */ +/* { dg-require-effective-target vect_int } */ + +#include "tree-vect.h" + +void __attribute__((noipa)) +foo (int * __restrict__ a, int * __restrict__ b, int * __restrict__ c, int n) +{ + int t = *c; + for (int i = 0; i < n; ++i) + { + b[i] = a[i] - t; + t = a[i]; + } +} + +int a[64], b[64]; + +int +main () +{ + check_vect (); + for (int i = 0; i < 64; ++i) + { + a[i] = i; + __asm__ volatile ("" ::: "memory"); + } + int c = 7; + foo (a, b, &c, 63); + for (int i = 1; i < 63; ++i) + if (b[i] != a[i] - a[i-1]) + abort (); + if (b[0] != -7) + abort (); + return 0; +} + +/* ??? We miss epilogue handling for first order recurrences. */ +/* { dg-final { scan-tree-dump "vectorized 1 loops in function" "vect" { target vect_fully_masked } } } */ diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc index 2536cc3cf49..b54820a960b 100644 --- a/gcc/tree-vect-loop.cc +++ b/gcc/tree-vect-loop.cc @@ -529,6 +529,45 @@ vect_inner_phi_in_double_reduction_p (loop_vec_info loop_vinfo, gphi *phi) return false; } +/* Returns true if Phi is a first-order recurrence. A first-order + recurrence is a non-reduction recurrence relation in which the value of + the recurrence in the current loop iteration equals a value defined in + the previous iteration. */ + +static bool +vect_phi_first_order_recurrence_p (loop_vec_info loop_vinfo, class loop *loop, + gphi *phi) +{ + /* Ensure the loop latch definition is from within the loop. */ + edge latch = loop_latch_edge (loop); + tree ldef = PHI_ARG_DEF_FROM_EDGE (phi, latch); + if (TREE_CODE (ldef) != SSA_NAME + || SSA_NAME_IS_DEFAULT_DEF (ldef) + || !flow_bb_inside_loop_p (loop, gimple_bb (SSA_NAME_DEF_STMT (ldef)))) + return false; + + tree def = gimple_phi_result (phi); + + /* Ensure every use_stmt of the phi node is dominated by the latch + definition. */ + imm_use_iterator imm_iter; + use_operand_p use_p; + FOR_EACH_IMM_USE_FAST (use_p, imm_iter, def) + if (!is_gimple_debug (USE_STMT (use_p)) + && (SSA_NAME_DEF_STMT (ldef) == USE_STMT (use_p) + || !vect_stmt_dominates_stmt_p (SSA_NAME_DEF_STMT (ldef), + USE_STMT (use_p)))) + return false; + + /* First-order recurrence autovectorization needs shuffle vector. */ + tree scalar_type = TREE_TYPE (def); + tree vectype = get_vectype_for_scalar_type (loop_vinfo, scalar_type); + if (!vectype) + return false; + + return true; +} + /* Function vect_analyze_scalar_cycles_1. Examine the cross iteration def-use cycles of scalar variables @@ -666,6 +705,8 @@ vect_analyze_scalar_cycles_1 (loop_vec_info loop_vinfo, class loop *loop, } } } + else if (vect_phi_first_order_recurrence_p (loop_vinfo, loop, phi)) + STMT_VINFO_DEF_TYPE (stmt_vinfo) = vect_first_order_recurrence; else if (dump_enabled_p ()) dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, @@ -1810,7 +1851,8 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo) if ((STMT_VINFO_RELEVANT (stmt_info) == vect_used_in_scope || STMT_VINFO_LIVE_P (stmt_info)) - && STMT_VINFO_DEF_TYPE (stmt_info) != vect_induction_def) + && STMT_VINFO_DEF_TYPE (stmt_info) != vect_induction_def + && STMT_VINFO_DEF_TYPE (stmt_info) != vect_first_order_recurrence) /* A scalar-dependence cycle that we don't support. */ return opt_result::failure_at (phi, "not vectorized:" @@ -1831,6 +1873,11 @@ vect_analyze_loop_operations (loop_vec_info loop_vinfo) && ! PURE_SLP_STMT (stmt_info)) ok = vectorizable_reduction (loop_vinfo, stmt_info, NULL, NULL, &cost_vec); + else if ((STMT_VINFO_DEF_TYPE (stmt_info) + == vect_first_order_recurrence) + && ! PURE_SLP_STMT (stmt_info)) + ok = vectorizable_recurr (loop_vinfo, stmt_info, NULL, NULL, + &cost_vec); } /* SLP PHIs are tested by vect_slp_analyze_node_operations. */ @@ -8267,6 +8314,183 @@ vectorizable_phi (vec_info *, return true; } +/* Vectorizes first order recurrences. */ + +bool +vectorizable_recurr (loop_vec_info loop_vinfo, stmt_vec_info stmt_info, + gimple **vec_stmt, slp_tree slp_node, + stmt_vector_for_cost *cost_vec) +{ + if (!loop_vinfo || !is_a (stmt_info->stmt)) + return false; + + gphi *phi = as_a (stmt_info->stmt); + + /* So far we only support first-order recurrence auto-vectorization. */ + if (STMT_VINFO_DEF_TYPE (stmt_info) != vect_first_order_recurrence) + return false; + + tree vectype = STMT_VINFO_VECTYPE (stmt_info); + unsigned ncopies; + if (slp_node) + ncopies = SLP_TREE_NUMBER_OF_VEC_STMTS (slp_node); + else + ncopies = vect_get_num_copies (loop_vinfo, vectype); + poly_int64 nunits = TYPE_VECTOR_SUBPARTS (vectype); + unsigned dist = slp_node ? SLP_TREE_LANES (slp_node) : 1; + /* We need to be able to make progress with a single vector. */ + if (maybe_gt (dist * 2, nunits)) + { + if (dump_enabled_p ()) + dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, + "first order recurrence exceeds half of " + "a vector\n"); + return false; + } + + /* First-order recurrence autovectorization needs to handle permutation + with indices = [nunits-1, nunits, nunits+1, ...]. */ + vec_perm_builder sel (nunits, 1, 3); + for (int i = 0; i < 3; ++i) + sel.quick_push (nunits - dist + i); + vec_perm_indices indices (sel, 1, nunits * 2); + + if (!vec_stmt) /* transformation not required. */ + { + if (!can_vec_perm_const_p (TYPE_MODE (vectype), TYPE_MODE (vectype), + indices)) + return false; + + if (slp_node) + { + /* We eventually need to set a vector type on invariant + arguments. */ + unsigned j; + slp_tree child; + FOR_EACH_VEC_ELT (SLP_TREE_CHILDREN (slp_node), j, child) + if (!vect_maybe_update_slp_op_vectype + (child, SLP_TREE_VECTYPE (slp_node))) + { + if (dump_enabled_p ()) + dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location, + "incompatible vector types for " + "invariants\n"); + return false; + } + } + /* The recurrence costs the initialization vector and one permute + for each copy. */ + unsigned prologue_cost = record_stmt_cost (cost_vec, 1, scalar_to_vec, + stmt_info, 0, vect_prologue); + unsigned inside_cost = record_stmt_cost (cost_vec, ncopies, vector_stmt, + stmt_info, 0, vect_body); + if (dump_enabled_p ()) + dump_printf_loc (MSG_NOTE, vect_location, + "vectorizable_recurr: inside_cost = %d, " + "prologue_cost = %d .\n", inside_cost, + prologue_cost); + + STMT_VINFO_TYPE (stmt_info) = recurr_info_type; + return true; + } + + /* This is the second phase of vectorizing first-order rececurrences. An + overview of the transformation is described below. Suppose we have the + following loop. + + int32_t t = 0; + for (int i = 0; i < n; ++i) + { + b[i] = a[i] - t; + t = a[i]; + } + + There is a first-order recurrence on "a". For this loop, the shorthand + scalar IR looks like: + + scalar.preheader: + init = a[-1] + br loop.body + + scalar.body: + i = PHI <0(scalar.preheader), i+1(scalar.body)> + _2 = PHI <(init(scalar.preheader), <_1(scalar.body)> + _1 = a[i] + b[i] = _1 - _2 + br cond, scalar.body, ... + + In this example, _2 is a recurrence because it's value depends on the + previous iteration. In the first phase of vectorization, we created a + temporary value for _2. We now complete the vectorization and produce the + shorthand vector IR shown below (VF = 4). + + vector.preheader: + vect_init = vect_cst(..., ..., ..., a[-1]) + br vector.body + + vector.body + i = PHI <0(vector.preheader), i+4(vector.body)> + vect_1 = PHI + vect_2 = a[i, i+1, i+2, i+3]; + vect_3 = vector(vect_1(3), vect_2(0, 1, 2)) + b[i, i+1, i+2, i+3] = vect_2 - vect_3 + br cond, vector.body, middle.block + + middle.block: + x = vect_2(3) + br scalar.preheader + + scalar.ph: + s_init = PHI + br scalar.body + + After execution completes the vector loop, we extract the next value of + the recurrence (x) to use as the initial value in the scalar loop. */ + + edge pe = loop_preheader_edge (LOOP_VINFO_LOOP (loop_vinfo)); + basic_block bb = gimple_bb (phi); + tree preheader = PHI_ARG_DEF_FROM_EDGE (phi, pe); + tree vec_init = build_vector_from_val (vectype, preheader); + vec_init = vect_init_vector (loop_vinfo, stmt_info, vec_init, vectype, NULL); + + /* Create the vectorized first-order PHI node. */ + tree vec_dest = vect_get_new_vect_var (vectype, + vect_simple_var, "vec_recur_"); + gphi *new_phi = create_phi_node (vec_dest, bb); + add_phi_arg (new_phi, vec_init, pe, UNKNOWN_LOCATION); + + /* Insert shuffles the first-order recurrence autovectorization. + result = VEC_PERM . */ + tree perm = vect_gen_perm_mask_checked (vectype, indices); + + /* Insert the required permute after the latch definition. The + second and later operands are tentative and will be updated when we have + vectorized the latch definition. */ + edge le = loop_latch_edge (LOOP_VINFO_LOOP (loop_vinfo)); + gimple_stmt_iterator gsi2 + = gsi_for_stmt (SSA_NAME_DEF_STMT (PHI_ARG_DEF_FROM_EDGE (phi, le))); + gsi_next (&gsi2); + + for (unsigned i = 0; i < ncopies; ++i) + { + vec_dest = make_ssa_name (vectype); + gassign *vperm + = gimple_build_assign (vec_dest, VEC_PERM_EXPR, + i == 0 ? gimple_phi_result (new_phi) : NULL, + NULL, perm); + vect_finish_stmt_generation (loop_vinfo, stmt_info, vperm, &gsi2); + + if (slp_node) + SLP_TREE_VEC_STMTS (slp_node).quick_push (vperm); + else + STMT_VINFO_VEC_STMTS (stmt_info).safe_push (vperm); + } + + if (!slp_node) + *vec_stmt = STMT_VINFO_VEC_STMTS (stmt_info)[0]; + return true; +} + /* Return true if VECTYPE represents a vector that requires lowering by the vector lowering pass. */ @@ -10223,27 +10447,53 @@ maybe_set_vectorized_backedge_value (loop_vec_info loop_vinfo, imm_use_iterator iter; use_operand_p use_p; FOR_EACH_IMM_USE_FAST (use_p, iter, def) - if (gphi *phi = dyn_cast (USE_STMT (use_p))) - if (gimple_bb (phi)->loop_father->header == gimple_bb (phi) - && (phi_info = loop_vinfo->lookup_stmt (phi)) - && STMT_VINFO_RELEVANT_P (phi_info) - && VECTORIZABLE_CYCLE_DEF (STMT_VINFO_DEF_TYPE (phi_info)) + { + gphi *phi = dyn_cast (USE_STMT (use_p)); + if (!phi) + continue; + if (!(gimple_bb (phi)->loop_father->header == gimple_bb (phi) + && (phi_info = loop_vinfo->lookup_stmt (phi)) + && STMT_VINFO_RELEVANT_P (phi_info))) + continue; + loop_p loop = gimple_bb (phi)->loop_father; + edge e = loop_latch_edge (loop); + if (PHI_ARG_DEF_FROM_EDGE (phi, e) != def) + continue; + + if (VECTORIZABLE_CYCLE_DEF (STMT_VINFO_DEF_TYPE (phi_info)) && STMT_VINFO_REDUC_TYPE (phi_info) != FOLD_LEFT_REDUCTION && STMT_VINFO_REDUC_TYPE (phi_info) != EXTRACT_LAST_REDUCTION) { - loop_p loop = gimple_bb (phi)->loop_father; - edge e = loop_latch_edge (loop); - if (PHI_ARG_DEF_FROM_EDGE (phi, e) == def) + vec &phi_defs = STMT_VINFO_VEC_STMTS (phi_info); + vec &latch_defs = STMT_VINFO_VEC_STMTS (def_stmt_info); + gcc_assert (phi_defs.length () == latch_defs.length ()); + for (unsigned i = 0; i < phi_defs.length (); ++i) + add_phi_arg (as_a (phi_defs[i]), + gimple_get_lhs (latch_defs[i]), e, + gimple_phi_arg_location (phi, e->dest_idx)); + } + else if (STMT_VINFO_DEF_TYPE (phi_info) == vect_first_order_recurrence) + { + /* For first order recurrences we have to update both uses of + the latch definition, the one in the PHI node and the one + in the generated VEC_PERM_EXPR. */ + vec &phi_defs = STMT_VINFO_VEC_STMTS (phi_info); + vec &latch_defs = STMT_VINFO_VEC_STMTS (def_stmt_info); + gcc_assert (phi_defs.length () == latch_defs.length ()); + tree phidef = gimple_assign_rhs1 (phi_defs[0]); + gphi *vphi = as_a (SSA_NAME_DEF_STMT (phidef)); + for (unsigned i = 0; i < phi_defs.length (); ++i) { - vec &phi_defs = STMT_VINFO_VEC_STMTS (phi_info); - vec &latch_defs = STMT_VINFO_VEC_STMTS (def_stmt_info); - gcc_assert (phi_defs.length () == latch_defs.length ()); - for (unsigned i = 0; i < phi_defs.length (); ++i) - add_phi_arg (as_a (phi_defs[i]), - gimple_get_lhs (latch_defs[i]), e, - gimple_phi_arg_location (phi, e->dest_idx)); + gassign *perm = as_a (phi_defs[i]); + if (i > 0) + gimple_assign_set_rhs1 (perm, gimple_get_lhs (latch_defs[i-1])); + gimple_assign_set_rhs2 (perm, gimple_get_lhs (latch_defs[i])); + update_stmt (perm); } + add_phi_arg (vphi, gimple_get_lhs (latch_defs.last ()), e, + gimple_phi_arg_location (phi, e->dest_idx)); } + } } /* Vectorize STMT_INFO if relevant, inserting any new instructions before GSI. @@ -10652,6 +10902,7 @@ vect_transform_loop (loop_vec_info loop_vinfo, gimple *loop_vectorized_call) || STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def || STMT_VINFO_DEF_TYPE (stmt_info) == vect_double_reduction_def || STMT_VINFO_DEF_TYPE (stmt_info) == vect_nested_cycle + || STMT_VINFO_DEF_TYPE (stmt_info) == vect_first_order_recurrence || STMT_VINFO_DEF_TYPE (stmt_info) == vect_internal_def) && ! PURE_SLP_STMT (stmt_info)) { @@ -10677,7 +10928,8 @@ vect_transform_loop (loop_vec_info loop_vinfo, gimple *loop_vectorized_call) || STMT_VINFO_DEF_TYPE (stmt_info) == vect_reduction_def || STMT_VINFO_DEF_TYPE (stmt_info) == vect_double_reduction_def || STMT_VINFO_DEF_TYPE (stmt_info) == vect_nested_cycle - || STMT_VINFO_DEF_TYPE (stmt_info) == vect_internal_def) + || STMT_VINFO_DEF_TYPE (stmt_info) == vect_internal_def + || STMT_VINFO_DEF_TYPE (stmt_info) == vect_first_order_recurrence) && ! PURE_SLP_STMT (stmt_info)) maybe_set_vectorized_backedge_value (loop_vinfo, stmt_info); } diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc index 229f2663ebc..cea5d50da92 100644 --- a/gcc/tree-vect-slp.cc +++ b/gcc/tree-vect-slp.cc @@ -693,6 +693,7 @@ vect_get_and_check_slp_defs (vec_info *vinfo, unsigned char swap, case vect_reduction_def: case vect_induction_def: case vect_nested_cycle: + case vect_first_order_recurrence: break; default: @@ -1732,7 +1733,8 @@ vect_build_slp_tree_2 (vec_info *vinfo, slp_tree node, } else if (def_type == vect_reduction_def || def_type == vect_double_reduction_def - || def_type == vect_nested_cycle) + || def_type == vect_nested_cycle + || def_type == vect_first_order_recurrence) { /* Else def types have to match. */ stmt_vec_info other_info; @@ -1746,7 +1748,8 @@ vect_build_slp_tree_2 (vec_info *vinfo, slp_tree node, } class loop *loop = LOOP_VINFO_LOOP (loop_vinfo); /* Reduction initial values are not explicitely represented. */ - if (!nested_in_vect_loop_p (loop, stmt_info)) + if (def_type != vect_first_order_recurrence + && !nested_in_vect_loop_p (loop, stmt_info)) skip_args[loop_preheader_edge (loop)->dest_idx] = true; /* Reduction chain backedge defs are filled manually. ??? Need a better way to identify a SLP reduction chain PHI. @@ -9187,11 +9190,34 @@ vect_schedule_scc (vec_info *vinfo, slp_tree node, slp_instance instance, child = SLP_TREE_CHILDREN (phi_node)[dest_idx]; if (!child || SLP_TREE_DEF_TYPE (child) != vect_internal_def) continue; + unsigned n = SLP_TREE_VEC_STMTS (phi_node).length (); /* Simply fill all args. */ - for (unsigned i = 0; i < SLP_TREE_VEC_STMTS (phi_node).length (); ++i) - add_phi_arg (as_a (SLP_TREE_VEC_STMTS (phi_node)[i]), - vect_get_slp_vect_def (child, i), - e, gimple_phi_arg_location (phi, dest_idx)); + if (STMT_VINFO_DEF_TYPE (SLP_TREE_REPRESENTATIVE (phi_node)) + != vect_first_order_recurrence) + for (unsigned i = 0; i < n; ++i) + add_phi_arg (as_a (SLP_TREE_VEC_STMTS (phi_node)[i]), + vect_get_slp_vect_def (child, i), + e, gimple_phi_arg_location (phi, dest_idx)); + else + { + /* Unless it is a first order recurrence which needs + args filled in for both the PHI node and the permutes. */ + gimple *perm = SLP_TREE_VEC_STMTS (phi_node)[0]; + gimple *rphi = SSA_NAME_DEF_STMT (gimple_assign_rhs1 (perm)); + add_phi_arg (as_a (rphi), + vect_get_slp_vect_def (child, n - 1), + e, gimple_phi_arg_location (phi, dest_idx)); + for (unsigned i = 0; i < n; ++i) + { + gimple *perm = SLP_TREE_VEC_STMTS (phi_node)[i]; + if (i > 0) + gimple_assign_set_rhs1 (perm, + vect_get_slp_vect_def (child, i - 1)); + gimple_assign_set_rhs2 (perm, + vect_get_slp_vect_def (child, i)); + update_stmt (perm); + } + } } } } diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc index c8d1efc45e5..4e0d75e0d75 100644 --- a/gcc/tree-vect-stmts.cc +++ b/gcc/tree-vect-stmts.cc @@ -11176,6 +11176,7 @@ vect_analyze_stmt (vec_info *vinfo, break; case vect_induction_def: + case vect_first_order_recurrence: gcc_assert (!bb_vinfo); break; @@ -11234,7 +11235,9 @@ vect_analyze_stmt (vec_info *vinfo, || vectorizable_comparison (vinfo, stmt_info, NULL, NULL, node, cost_vec) || vectorizable_lc_phi (as_a (vinfo), - stmt_info, NULL, node)); + stmt_info, NULL, node) + || vectorizable_recurr (as_a (vinfo), + stmt_info, NULL, node, cost_vec)); else { if (bb_vinfo) @@ -11404,6 +11407,12 @@ vect_transform_stmt (vec_info *vinfo, gcc_assert (done); break; + case recurr_info_type: + done = vectorizable_recurr (as_a (vinfo), + stmt_info, &vec_stmt, slp_node, NULL); + gcc_assert (done); + break; + case phi_info_type: done = vectorizable_phi (vinfo, stmt_info, &vec_stmt, slp_node, NULL); gcc_assert (done); @@ -11804,6 +11813,9 @@ vect_is_simple_use (tree operand, vec_info *vinfo, enum vect_def_type *dt, case vect_nested_cycle: dump_printf (MSG_NOTE, "nested cycle\n"); break; + case vect_first_order_recurrence: + dump_printf (MSG_NOTE, "first order recurrence\n"); + break; case vect_unknown_def_type: dump_printf (MSG_NOTE, "unknown\n"); break; @@ -11852,7 +11864,8 @@ vect_is_simple_use (tree operand, vec_info *vinfo, enum vect_def_type *dt, || *dt == vect_induction_def || *dt == vect_reduction_def || *dt == vect_double_reduction_def - || *dt == vect_nested_cycle) + || *dt == vect_nested_cycle + || *dt == vect_first_order_recurrence) { *vectype = STMT_VINFO_VECTYPE (def_stmt_info); gcc_assert (*vectype != NULL_TREE); diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h index 4870c754499..016961da851 100644 --- a/gcc/tree-vectorizer.h +++ b/gcc/tree-vectorizer.h @@ -65,6 +65,7 @@ enum vect_def_type { vect_reduction_def, vect_double_reduction_def, vect_nested_cycle, + vect_first_order_recurrence, vect_unknown_def_type }; @@ -1027,6 +1028,7 @@ enum stmt_vec_info_type { cycle_phi_info_type, lc_phi_info_type, phi_info_type, + recurr_info_type, loop_exit_ctrl_vec_info_type }; @@ -2331,6 +2333,8 @@ extern bool vectorizable_lc_phi (loop_vec_info, stmt_vec_info, gimple **, slp_tree); extern bool vectorizable_phi (vec_info *, stmt_vec_info, gimple **, slp_tree, stmt_vector_for_cost *); +extern bool vectorizable_recurr (loop_vec_info, stmt_vec_info, + gimple **, slp_tree, stmt_vector_for_cost *); extern bool vect_emulated_vector_p (tree); extern bool vect_can_vectorize_without_simd_p (tree_code); extern bool vect_can_vectorize_without_simd_p (code_helper);