From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1005) id AA58B3858D3C; Thu, 24 Mar 2022 19:31:16 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org AA58B3858D3C Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Michael Meissner To: gcc-cvs@gcc.gnu.org Subject: [gcc(refs/users/meissner/heads/work083)] Optimize vec_splats of constant vec_extract for V2DI/V2DF. X-Act-Checkin: gcc X-Git-Author: Michael Meissner X-Git-Refname: refs/users/meissner/heads/work083 X-Git-Oldrev: 0c2ea37dd810c76f7d7114b6ded2599cb32e8de8 X-Git-Newrev: 1ea03fd63e73015e28cfb8a6772123703130eb45 Message-Id: <20220324193116.AA58B3858D3C@sourceware.org> Date: Thu, 24 Mar 2022 19:31:16 +0000 (GMT) X-BeenThere: gcc-cvs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-cvs mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 24 Mar 2022 19:31:16 -0000 https://gcc.gnu.org/g:1ea03fd63e73015e28cfb8a6772123703130eb45 commit 1ea03fd63e73015e28cfb8a6772123703130eb45 Author: Michael Meissner Date: Thu Mar 24 15:30:58 2022 -0400 Optimize vec_splats of constant vec_extract for V2DI/V2DF. In PR target/99293, it was pointed out that doing: vector long long dest0, dest1, src; /* ... */ dest0 = vec_splats (vec_extract (src, 0)); dest1 = vec_splats (vec_extract (src, 1)); would generate slower code. It generates the following code on power8: ;; vec_splats (vec_extract (src, 0)) xxpermdi 0,34,34,3 xxpermdi 34,0,0,0 ;; vec_splats (vec_extract (src, 1)) xxlor 0,34,34 xxpermdi 34,0,0,0 However on power9 and power10 it generates: ;; vec_splats (vec_extract (src, 0)) mfvsld 3,34 mtvsrdd 34,9,9 ;; vec_splats (vec_extract (src, 1)) mfvsrd 9,34 mtvsrdd 34,9,9 This is due to the power9 having the mfvsrld instruction which can extract either 64-bit element into a GPR. However in this case, it is better to have a single combiner pattern that can generate a single xxpermdi, instead of doing 2 insnsns (the extract and then the concat). 2022-03-24 Michael Meissner gcc/ PR target/99392 * config/rs6000/vsx.md (vsx_splat_const_extract_): New combiner insn. gcc/testsuite: PR target/99392 * gcc.target/powerpc/pr99293.c: New test. Diff: --- gcc/config/rs6000/vsx.md | 19 ++++++++++++++++ gcc/testsuite/gcc.target/powerpc/pr99293.c | 36 ++++++++++++++++++++++++++++++ 2 files changed, 55 insertions(+) diff --git a/gcc/config/rs6000/vsx.md b/gcc/config/rs6000/vsx.md index 15bd86dfdfb..ddafbe471dd 100644 --- a/gcc/config/rs6000/vsx.md +++ b/gcc/config/rs6000/vsx.md @@ -4616,6 +4616,25 @@ [(set_attr "type" "vecperm") (set_attr "isa" "p8v,*")]) +;; Optimize SPLAT of an extract from a V2DF/V2DI vector with a constant element +;; PR target/99293 +(define_insn "*vsx_splat_const_extract_" + [(set (match_operand:VSX_D 0 "vsx_register_operand" "=wa") + (vec_duplicate:VSX_D + (vec_select: + (match_operand:VSX_D 1 "vsx_register_operand" "wa") + (parallel [(match_operand 2 "const_0_to_1_operand" "n")]))))] + "VECTOR_MEM_VSX_P (mode)" +{ + int which_word = INTVAL (operands[2]); + if (!BYTES_BIG_ENDIAN) + which_word = 1 - which_word; + + operands[3] = GEN_INT (which_word ? 3 : 0); + return "xxpermdi %x0,%x1,%x1,%3"; +} + [(set_attr "type" "vecperm")]) + ;; V4SF splat (ISA 3.0) (define_insn_and_split "vsx_splat_v4sf" [(set (match_operand:V4SF 0 "vsx_register_operand" "=wa,wa,wa") diff --git a/gcc/testsuite/gcc.target/powerpc/pr99293.c b/gcc/testsuite/gcc.target/powerpc/pr99293.c new file mode 100644 index 00000000000..13b5ed5b0b1 --- /dev/null +++ b/gcc/testsuite/gcc.target/powerpc/pr99293.c @@ -0,0 +1,36 @@ +/* { dg-do compile { target powerpc*-*-* } } */ +/* { dg-require-effective-target powerpc_vsx_ok } */ +/* { dg-options "-O2 -mvsx" } */ + +/* Test for PR 99263, which wants to do: + __builtin_vec_splats (__builtin_vec_extract (v, n)) + + where v is a V2DF or V2DI vector and n is either 0 or 1. Previously the + compiler would do a direct move to the GPR registers to select the item and + a direct move from the GPR registers to do the splat. */ + +vector long long +splat_dup_ll_0 (vector long long v) +{ + return __builtin_vec_splats (__builtin_vec_extract (v, 0)); +} + +vector long long +splat_dup_ll_1 (vector long long v) +{ + return __builtin_vec_splats (__builtin_vec_extract (v, 1)); +} + +vector double +splat_dup_d_0 (vector double v) +{ + return __builtin_vec_splats (__builtin_vec_extract (v, 0)); +} + +vector double +splat_dup_d_1 (vector double v) +{ + return __builtin_vec_splats (__builtin_vec_extract (v, 1)); +} + +/* { dg-final { scan-assembler-times "xxpermdi" 4 } } */