From patchwork Wed Oct 23 09:08:47 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Li Xu X-Patchwork-Id: 99384 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 9D3BD3856DF7 for ; Wed, 23 Oct 2024 09:09:25 +0000 (GMT) X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from eswincomputing.com (mail.eswincomputing.com [123.124.195.78]) by sourceware.org (Postfix) with ESMTP id 92B4F3858C41 for ; Wed, 23 Oct 2024 09:08:51 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 92B4F3858C41 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=eswincomputing.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=eswincomputing.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 92B4F3858C41 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=123.124.195.78 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1729674543; cv=none; b=J3or5UmnIHJrvO+55Zlla9xn9+dyilZ+ijquRw9cSdy6XHBDW3xKKKhsRQsM8k5vfNKYYhLy5wrmaodU/IDzvhEL6mQA+BD4PVynqAXR1yeLkrCPCayoSLbWk8+e6lkJpOv7GY3iBF6XsQngnYQqCTuFRlk/tHDCSUASgb+ASM0= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1729674543; c=relaxed/simple; bh=gZOBnteTncIaPIVqXA8hNP44uDxyauXK1bNGzm0yFu4=; h=From:To:Subject:Date:Message-Id; b=lfDGopM7zaMgqONjGRI5kZK91xgNSroWzVI6LVXpzeDaLI/KDXPycM76jvXpD9l8POBSKwx7RTV/gALyzGFKb0dYxUPQ2619rYKfcwi3akLeo0hk//s92+UA6PqByk4N9Y/xUm+LQdtfXhWEAL351U+n0BKvhvehr0FPAXqeXlk= ARC-Authentication-Results: i=1; server2.sourceware.org Received: from host014-ubuntu-1804.lxd (unknown [10.12.130.31]) by app1 (Coremail) with SMTP id TAJkCgBXh+UgvRhn4vUPAA--.11016S4; Wed, 23 Oct 2024 17:08:49 +0800 (CST) From: Li Xu To: gcc-patches@gcc.gnu.org Cc: kito.cheng@gmail.com, richard.guenther@gmail.com, Tamar.Christina@arm.com, juzhe.zhong@rivai.ai, pan2.li@intel.com, jeffreyalaw@gmail.com, rdapp.gcc@gmail.com, pinskia@gmail.com, xuli Subject: [PATCH 1/2 v3] Match: Simplify unsigned scalar sat_sub(x, 1) to (x - x != 0) Date: Wed, 23 Oct 2024 09:08:47 +0000 Message-Id: <20241023090847.17589-1-xuli1@eswincomputing.com> X-Mailer: git-send-email 2.17.1 X-CM-TRANSID: TAJkCgBXh+UgvRhn4vUPAA--.11016S4 X-Coremail-Antispam: 1UD129KBjvJXoWxWry3Zr18KFyrGF47Wry7Awb_yoW5uF13p3 y8Xa4Fg3yxtF1xWF4xCFy5AF13K3Z3GryUWrW7Ww1qkFn2yr97WFy0k3yfCr4fGayUWr4f XanrWw1rC3W8X37anT9S1TB71UUUUU7qnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUU9G14x267AKxVW8JVW5JwAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2ocxC64kIII0Yj41l84x0c7CEw4AK67xGY2AK02 1l84ACjcxK6xIIjxv20xvE14v26w1j6s0DM28EF7xvwVC0I7IYx2IY6xkF7I0E14v26r4U JVWxJr1l84ACjcxK6I8E87Iv67AKxVW0oVCq3wA2z4x0Y4vEx4A2jsIEc7CjxVAFwI0_Gc CE3s1le2I262IYc4CY6c8Ij28IcVAaY2xG8wAqx4xG64xvF2IEw4CE5I8CrVC2j2WlYx0E 2Ix0cI8IcVAFwI0_JrI_JrylYx0Ex4A2jsIE14v26r1j6r4UMcvjeVCFs4IE7xkEbVWUJV W8JwACjcxG0xvY0x0EwIxGrwACjI8F5VA0II8E6IAqYI8I648v4I1lFIxGxcIEc7CjxVA2 Y2ka0xkIwI1lc7CjxVAaw2AFwI0_Jw0_GFylc2xSY4AK6svPMxAIw28IcxkI7VAKI48JMx C20s026xCaFVCjc4AY6r1j6r4UMI8I3I0E5I8CrVAFwI0_Jr0_Jr4lx2IqxVCjr7xvwVAF wI0_JrI_JrWlx4CE17CEb7AF67AKxVWUtVW8ZwCIc40Y0x0EwIxGrwCI42IY6xIIjxv20x vE14v26r1j6r1xMIIF0xvE2Ix0cI8IcVCY1x0267AKxVW8JVWxJwCI42IY6xAIw20EY4v2 0xvaj40_Jr0_JF4lIxAIcVC2z280aVAFwI0_Jr0_Gr1lIxAIcVC2z280aVCY1x0267AKxV W8JVW8JrUvcSsGvfC2KfnxnUUI43ZEXa7VU13ku3UUUUU== X-CM-SenderInfo: 50xoxi46hv4xpqfrz1xxwl0woofrz/ X-Spam-Status: No, score=-13.0 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_PASS, 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: 2.1.30 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: gcc-patches-bounces~patchwork=sourceware.org@gcc.gnu.org From: xuli When the imm operand op1=1 in the unsigned scalar sat_sub form2 below, we can simplify (x != 0 ? x + max : 0) to (x - x != 0), thereby eliminating a branch instruction. Form2: T __attribute__((noinline)) \ sat_u_sub_imm##IMM##_##T##_fmt_2 (T x) \ { \ return x >= (T)IMM ? x - (T)IMM : 0; \ } Take below form 2 as example: DEF_SAT_U_SUB_IMM_FMT_2(uint8_t, 1) Before this patch: __attribute__((noinline)) uint8_t sat_u_sub_imm1_uint8_t_fmt_2 (uint8_t x) { uint8_t _1; uint8_t _3; [local count: 1073741824]: if (x_2(D) != 0) goto ; [50.00%] else goto ; [50.00%] [local count: 536870912]: _3 = x_2(D) + 255; [local count: 1073741824]: # _1 = PHI return _1; } Assembly code: sat_u_sub_imm1_uint8_t_fmt_2: beq a0,zero,.L2 addiw a0,a0,-1 andi a0,a0,0xff .L2: ret After this patch: __attribute__((noinline)) uint8_t sat_u_sub_imm1_uint8_t_fmt_2 (uint8_t x) { _Bool _1; unsigned char _2; uint8_t _4; [local count: 1073741824]: _1 = x_3(D) != 0; _2 = (unsigned char) _1; _4 = x_3(D) - _2; return _4; } Assembly code: sat_u_sub_imm1_uint8_t_fmt_2: snez a5,a0 subw a0,a0,a5 andi a0,a0,0xff ret The below test suites are passed for this patch: 1. The rv64gcv fully regression tests. 2. The x86 bootstrap tests. 3. The x86 fully regression tests. Signed-off-by: Li Xu gcc/ChangeLog: * match.pd: Simplify (x != 0 ? x + max : 0) to (x - x != 0). gcc/testsuite/ChangeLog: * gcc.dg/tree-ssa/phi-opt-44.c: New test. --- gcc/match.pd | 9 ++++++++ gcc/testsuite/gcc.dg/tree-ssa/phi-opt-44.c | 26 ++++++++++++++++++++++ 2 files changed, 35 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/tree-ssa/phi-opt-44.c diff --git a/gcc/match.pd b/gcc/match.pd index 0455dfa6993..6a245f8e0d3 100644 --- a/gcc/match.pd +++ b/gcc/match.pd @@ -3383,6 +3383,15 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) } (if (wi::eq_p (sum, wi::uhwi (0, precision))))))) +/* The boundary condition for case 10: IMM = 1: + SAT_U_SUB = X >= IMM ? (X - IMM) : 0. + simplify (X != 0 ? X + max : 0) to (X - X != 0). */ +(simplify + (cond (ne @0 integer_zerop) (plus @0 integer_all_onesp) integer_zerop) + (if (INTEGRAL_TYPE_P (type) && TYPE_UNSIGNED (type) + && types_match (type, @0)) + (minus @0 (convert (ne @0 { build_zero_cst (type); }))))) + /* Signed saturation sub, case 1: T minus = (T)((UT)X - (UT)Y); SAT_S_SUB = (X ^ Y) & (X ^ minus) < 0 ? (-(T)(X < 0) ^ MAX) : minus; diff --git a/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-44.c b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-44.c new file mode 100644 index 00000000000..756ba065d84 --- /dev/null +++ b/gcc/testsuite/gcc.dg/tree-ssa/phi-opt-44.c @@ -0,0 +1,26 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -fdump-tree-phiopt1" } */ + +#include + +uint8_t sat_u_imm1_uint8_t (uint8_t x) +{ + return x >= (uint8_t)1 ? x - (uint8_t)1 : 0; +} + +uint16_t sat_u_imm1_uint16_t (uint16_t x) +{ + return x >= (uint16_t)1 ? x - (uint16_t)1 : 0; +} + +uint32_t sat_u_imm1_uint32_t (uint32_t x) +{ + return x >= (uint32_t)1 ? x - (uint32_t)1 : 0; +} + +uint64_t sat_u_imm1_uint64_t (uint64_t x) +{ + return x >= (uint64_t)1 ? x - (uint64_t)1 : 0; +} + +/* { dg-final { scan-tree-dump-not "goto" "phiopt1" } } */