arm: Implement SVE2 str2int

This patch implements a SVE2 version of str2int which improves number decoding on ARM SVE2 CPUs. The algorithm utilizes SVMATCH to count valid digits in the string, and SDOT for calculating the value. With this change the naive byte-by-byte method for ARM is substituted. Enable it by compiling with adding cmake option "-DENABLE_SVE2_128=ON". | Benchmark | Original | SVE2 | Improvement | |--------------------------------|--------------|------------|-------------| | testdata/gsoc-2018.json | 3406307500 | 3407847500 | 0.05% | | testdata/twitter.json | 2040162500 | 2039502500 | -0.03% | | testdata/fgo.json | 992470750 | 988730000 | -0.38% | | testdata/citm_catalog.json | 2209855000 | 2205997500 | -0.17% | | testdata/twitterescaped.json | 1767812500 | 1814302500 | 2.63% | | testdata/github_events.json | 2142690000 | 2147452500 | 0.22% | | testdata/lottie.json | 625985250 | 602068500 | -3.82% | | testdata/poet.json | 2867745000 | 2880562500 | 0.45% | | testdata/otfcc.json | 685481500 | 683760750 | -0.25% | | testdata/book.json | 687309000 | 674716000 | -1.83% | | testdata/canada.json | 775475000 | 1051945000 | 35.65% | Signed-off-by: Yuzhong Wen <[email protected]>
bytedance · Sep 11, 2024 · 5b2d104 · 5b2d104
1 parent 70821cb
commit 5b2d104
Showing 1 changed file with 106 additions and 3 deletions.
diff --git a/include/sonic/internal/arch/sve2-128/str2int.h b/include/sonic/internal/arch/sve2-128/str2int.h
@@ -1,11 +1,13 @@
 /*
+ * SPDX-FileCopyrightText: Copyright (c) 2024 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
+ * SPDX-License-Identifier: Apache-2.0
  * Copyright 2022 ByteDance Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ * http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -16,13 +18,114 @@
 
 #pragma once
 
-#include "../common/arm_common/str2int.h"
+#include <arm_sve.h>
 
 namespace sonic_json {
 namespace internal {
 namespace sve2_128 {
 
-using sonic_json::internal::arm_common::simd_str2int;
+const int16_t d8d[] = {1000, 100, 10, 1, 1000, 100, 10, 1};
+const int16_t d4d[] = {1000, 100, 10, 1, 0, 0, 0, 0};
+const int64_t d2d[] = {10000, 1, 100000000, 10000};
+const uint8_t ldigits[] = {'1','2','3','4','5','6','7','8','9','0','0','0','0','0','0','0'};
+
+sonic_force_inline uint64_t digit_cnt(svint8_t in)
+{
+  const svbool_t ptrue = svptrue_b8();
+  svint8_t dd = svld1_s8(ptrue, reinterpret_cast<const signed char*>(&ldigits[0]));
+  svbool_t cg = svmatch_s8(ptrue, in, dd);
+  cg = sveor_b_z(ptrue, cg, ptrue);
+  cg = svbrkb_z(ptrue, cg);
+  return svcntp_b8(ptrue, cg);
+}
+
+sonic_force_inline uint64_t simd_str2int_sve_8(svint16_t in)
+{
+  const svbool_t ptrue = svptrue_b16();
+  svint16_t lu1 = svld1_s16(ptrue, reinterpret_cast<const int16_t*>(&d8d[0]));
+  svint64_t lu2 = svld1_s64(svptrue_b64(), reinterpret_cast<const int64_t*>(&d2d[0]));
+
+  svint64_t r1 = svdot(svdup_n_s64(0), lu1, in);
+  r1 = svmul_m(svptrue_b64(), lu2, r1);
+  return svaddv_s64(svptrue_b64(), r1);
+}
+
+sonic_force_inline uint64_t simd_str2int_sve_l8(svint16_t in, uint32_t len)
+{
+  const svbool_t ptrue = svptrue_b16();
+  svbool_t cg = svwhilelt_b16(0u, len);
+  cg = sveor_b_z(ptrue, cg, ptrue);
+  svint16_t d = svsplice_s16(cg, svdup_s16(0), in);
+
+  return simd_str2int_sve_8(d);
+}
+
+sonic_force_inline uint64_t simd_str2int_sve_12(svint16_t inlo, svint16_t inhi)
+{
+  const svbool_t ptrue = svptrue_b16();
+  svint16_t lu1 = svld1_s16(ptrue, reinterpret_cast<const int16_t*>(&d8d[0]));
+  svint64_t lu2 = svld1_s64(svptrue_b64(), reinterpret_cast<const int64_t*>(&d2d[2]));
+
+  svint64_t r1 = svdot(svdup_n_s64(0), lu1, inlo);
+  r1 = svmul_m(svptrue_b64(), lu2, r1);
+
+  lu1 = svld1_s16(ptrue, &d4d[0]);
+  svint64_t r2 = svdot(svdup_n_s64(0), lu1, inhi);
+
+  r2 = svadd_s64_x(svptrue_b64(), r2, r1);
+  return svaddv_s64(svptrue_b64(), r2);
+}
+
+sonic_force_inline uint64_t simd_str2int(const char* c, int& man_nd)
+{
+  svint8_t in = svld1_s8(svptrue_b8(), reinterpret_cast<const signed char*>(&c[0]));
+  int len = (int)digit_cnt(in);
+  uint64_t ret = 1;
+  man_nd = man_nd < len ? man_nd : len;
+  in = svsub_n_s8_x(svptrue_b8(), in, '0');
+  switch(man_nd) {
+    case 1:
+    case 2:
+    case 3:
+    case 4:
+    case 5:
+    case 6:
+    case 7:
+      ret = simd_str2int_sve_l8(svunpklo_s16(in), man_nd);
+      break;
+    case 8:
+      ret = simd_str2int_sve_8(svunpklo_s16(in));
+      break;
+    case 9:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 10ull + simd_str2int_sve_l8(svunpkhi_s16(in), 1);
+      break;
+    case 10:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 100ull + simd_str2int_sve_l8(svunpkhi_s16(in), 2);
+      break;
+    case 11:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 1000ull + simd_str2int_sve_l8(svunpkhi_s16(in), 3);
+      break;
+    case 12:
+      ret = simd_str2int_sve_12(svunpklo_s16(in), svunpkhi_s16(in));
+      break;
+    case 13:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 100000ull + simd_str2int_sve_l8(svunpkhi_s16(in), 5);
+      break;
+    case 14:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 1000000ull + simd_str2int_sve_l8(svunpkhi_s16(in), 6);
+      break;
+    case 15:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 10000000ull + simd_str2int_sve_l8(svunpkhi_s16(in), 7);
+      break;
+    case 16:
+      ret = simd_str2int_sve_8(svunpklo_s16(in)) * 100000000ull + simd_str2int_sve_8(svunpkhi_s16(in));
+      break;
+    default:
+      ret = 0;
+      break;
+  }
+  return ret;
+}
 
 }  // namespace sve2_128
 }  // namespace internal