third_party/utf8_range: support arm neon (protocolbuffers#18126)

Protobuf uses utf8_range library for utf8 string validation.
Currently, only SSE implementation is integrated.
This patch adapts utf8_range Neon implementation to protobuf.

Closes protocolbuffers#18126

COPYBARA_INTEGRATE_REVIEW=protocolbuffers#18126 from cyb70289:utf8-neon 5edbcc2
PiperOrigin-RevId: 680711032

Author: cyb70289

ruby/.gitignore

@@ -9,5 +9,7 @@ tmp/
 tests/google/
 ext/google/protobuf_c/third_party/utf8_range/utf8_range.h
 ext/google/protobuf_c/third_party/utf8_range/utf8_range.c
+ext/google/protobuf_c/third_party/utf8_range/utf8_range_sse.inc
+ext/google/protobuf_c/third_party/utf8_range/utf8_range_neon.inc
 ext/google/protobuf_c/third_party/utf8_range/LICENSE
 lib/google/protobuf/*_pb.rb

ruby/Rakefile

@@ -81,7 +81,7 @@ task :copy_third_party do
     # We need utf8_range in-tree.
     utf8_root = '../third_party/utf8_range'
     %w[
-      utf8_range.h utf8_range.c LICENSE
+      utf8_range.h utf8_range.c utf8_range_sse.inc utf8_range_neon.inc LICENSE
     ].each do |file|
       FileUtils.cp File.join(utf8_root, file),
                    "ext/google/protobuf_c/third_party/utf8_range"

third_party/utf8_range/BUILD.bazel

@@ -35,6 +35,8 @@ filegroup(
     srcs = [
         "utf8_range.c",
         "utf8_range.h",
+        "utf8_range_neon.inc",
+        "utf8_range_sse.inc",
     ],
     visibility = ["//:__subpackages__"],
 )
@@ -44,7 +46,11 @@ cc_library(
     srcs = [
         "utf8_range.c",
     ],
-    hdrs = ["utf8_range.h"],
+    hdrs = [
+        "utf8_range.h",
+        "utf8_range_neon.inc",
+        "utf8_range_sse.inc",
+    ],
     strip_include_prefix = "/third_party/utf8_range",
 )
 

third_party/utf8_range/utf8_range.c

@@ -21,12 +21,6 @@
 #include <stdint.h>
 #include <string.h>
 
-#ifdef __SSE4_1__
-#include <emmintrin.h>
-#include <smmintrin.h>
-#include <tmmintrin.h>
-#endif
-
 #if defined(__GNUC__)
 #define FORCE_INLINE_ATTR __attribute__((always_inline))
 #elif defined(_MSC_VER)
@@ -143,7 +137,7 @@ static size_t utf8_range_ValidateUTF8Naive(const char* data, const char* end,
   return err_pos + (1 - return_position);
 }
 
-#ifdef __SSE4_1__
+#if defined(__SSE4_1__) || (defined(__ARM_NEON) && defined(__ARM_64BIT_STATE))
 /* Returns the number of bytes needed to skip backwards to get to the first
    byte of codepoint.
  */
@@ -175,6 +169,12 @@ static inline const char* utf8_range_SkipAscii(const char* data,
   return data;
 }
 
+#if defined(__SSE4_1__)
+#include "utf8_range_sse.inc"
+#elif defined(__ARM_NEON) && defined(__ARM_64BIT_STATE)
+#include "utf8_range_neon.inc"
+#endif
+
 static FORCE_INLINE_ATTR inline size_t utf8_range_Validate(
     const char* data, size_t len, int return_position) {
   if (len == 0) return 1 - return_position;
@@ -187,274 +187,11 @@ static FORCE_INLINE_ATTR inline size_t utf8_range_Validate(
     return (return_position ? (data - (end - len)) : 0) +
            utf8_range_ValidateUTF8Naive(data, end, return_position);
   }
-#ifndef __SSE4_1__
+#if defined(__SSE4_1__) || (defined(__ARM_NEON) && defined(__ARM_64BIT_STATE))
+  return utf8_range_ValidateUTF8Simd(data, end, return_position);
+#else
   return (return_position ? (data - (end - len)) : 0) +
          utf8_range_ValidateUTF8Naive(data, end, return_position);
-#else
-  /* This code checks that utf-8 ranges are structurally valid 16 bytes at once
-   * using superscalar instructions.
-   * The mapping between ranges of codepoint and their corresponding utf-8
-   * sequences is below.
-   */
-
-  /*
-   * U+0000...U+007F     00...7F
-   * U+0080...U+07FF     C2...DF 80...BF
-   * U+0800...U+0FFF     E0      A0...BF 80...BF
-   * U+1000...U+CFFF     E1...EC 80...BF 80...BF
-   * U+D000...U+D7FF     ED      80...9F 80...BF
-   * U+E000...U+FFFF     EE...EF 80...BF 80...BF
-   * U+10000...U+3FFFF   F0      90...BF 80...BF 80...BF
-   * U+40000...U+FFFFF   F1...F3 80...BF 80...BF 80...BF
-   * U+100000...U+10FFFF F4      80...8F 80...BF 80...BF
-   */
-
-  /* First we compute the type for each byte, as given by the table below.
-   * This type will be used as an index later on.
-   */
-
-  /*
-   * Index  Min Max Byte Type
-   *  0     00  7F  Single byte sequence
-   *  1,2,3 80  BF  Second, third and fourth byte for many of the sequences.
-   *  4     A0  BF  Second byte after E0
-   *  5     80  9F  Second byte after ED
-   *  6     90  BF  Second byte after F0
-   *  7     80  8F  Second byte after F4
-   *  8     C2  F4  First non ASCII byte
-   *  9..15 7F  80  Invalid byte
-   */
-
-  /* After the first step we compute the index for all bytes, then we permute
-     the bytes according to their indices to check the ranges from the range
-     table.
-   * The range for a given type can be found in the range_min_table and
-     range_max_table, the range for type/index X is in range_min_table[X] ...
-     range_max_table[X].
-   */
-
-  /* Algorithm:
-   * Put index zero to all bytes.
-   * Find all non ASCII characters, give them index 8.
-   * For each tail byte in a codepoint sequence, give it an index corresponding
-     to the 1 based index from the end.
-   * If the first byte of the codepoint is in the [C0...DF] range, we write
-     index 1 in the following byte.
-   * If the first byte of the codepoint is in the range [E0...EF], we write
-     indices 2 and 1 in the next two bytes.
-   * If the first byte of the codepoint is in the range [F0...FF] we write
-     indices 3,2,1 into the next three bytes.
-   * For finding the number of bytes we need to look at high nibbles (4 bits)
-     and do the lookup from the table, it can be done with shift by 4 + shuffle
-     instructions. We call it `first_len`.
-   * Then we shift first_len by 8 bits to get the indices of the 2nd bytes.
-   * Saturating sub 1 and shift by 8 bits to get the indices of the 3rd bytes.
-   * Again to get the indices of the 4th bytes.
-   * Take OR of all that 4 values and check within range.
-   */
-  /* For example:
-   * input       C3 80 68 E2 80 20 A6 F0 A0 80 AC 20 F0 93 80 80
-   * first_len   1  0  0  2  0  0  0  3  0  0  0  0  3  0  0  0
-   * 1st byte    8  0  0  8  0  0  0  8  0  0  0  0  8  0  0  0
-   * 2nd byte    0  1  0  0  2  0  0  0  3  0  0  0  0  3  0  0 // Shift + sub
-   * 3rd byte    0  0  0  0  0  1  0  0  0  2  0  0  0  0  2  0 // Shift + sub
-   * 4th byte    0  0  0  0  0  0  0  0  0  0  1  0  0  0  0  1 // Shift + sub
-   * Index       8  1  0  8  2  1  0  8  3  2  1  0  8  3  2  1 // OR of results
-   */
-
-  /* Checking for errors:
-   * Error checking is done by looking up the high nibble (4 bits) of each byte
-     against an error checking table.
-   * Because the lookup value for the second byte depends of the value of the
-     first byte in codepoint, we use saturated operations to adjust the index.
-   * Specifically we need to add 2 for E0, 3 for ED, 3 for F0 and 4 for F4 to
-     match the correct index.
-       * If we subtract from all bytes EF then EO -> 241, ED -> 254, F0 -> 1,
-         F4 -> 5
-       * Do saturating sub 240, then E0 -> 1, ED -> 14 and we can do lookup to
-         match the adjustment
-       * Add saturating 112, then F0 -> 113, F4 -> 117, all that were > 16 will
-         be more 128 and lookup in ef_fe_table will return 0 but for F0
-         and F4 it will be 4 and 5 accordingly
-   */
-  /*
-   * Then just check the appropriate ranges with greater/smaller equal
-     instructions. Check tail with a naive algorithm.
-   * To save from previous 16 byte checks we just align previous_first_len to
-     get correct continuations of the codepoints.
-   */
-
-  /*
-   * Map high nibble of "First Byte" to legal character length minus 1
-   * 0x00 ~ 0xBF --> 0
-   * 0xC0 ~ 0xDF --> 1
-   * 0xE0 ~ 0xEF --> 2
-   * 0xF0 ~ 0xFF --> 3
-   */
-  const __m128i first_len_table =
-      _mm_setr_epi8(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 3);
-
-  /* Map "First Byte" to 8-th item of range table (0xC2 ~ 0xF4) */
-  const __m128i first_range_table =
-      _mm_setr_epi8(0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 8, 8, 8, 8);
-
-  /*
-   * Range table, map range index to min and max values
-   */
-  const __m128i range_min_table =
-      _mm_setr_epi8(0x00, 0x80, 0x80, 0x80, 0xA0, 0x80, 0x90, 0x80, 0xC2, 0x7F,
-                    0x7F, 0x7F, 0x7F, 0x7F, 0x7F, 0x7F);
-
-  const __m128i range_max_table =
-      _mm_setr_epi8(0x7F, 0xBF, 0xBF, 0xBF, 0xBF, 0x9F, 0xBF, 0x8F, 0xF4, 0x80,
-                    0x80, 0x80, 0x80, 0x80, 0x80, 0x80);
-
-  /*
-   * Tables for fast handling of four special First Bytes(E0,ED,F0,F4), after
-   * which the Second Byte are not 80~BF. It contains "range index adjustment".
-   * +------------+---------------+------------------+----------------+
-   * | First Byte | original range| range adjustment | adjusted range |
-   * +------------+---------------+------------------+----------------+
-   * | E0         | 2             | 2                | 4              |
-   * +------------+---------------+------------------+----------------+
-   * | ED         | 2             | 3                | 5              |
-   * +------------+---------------+------------------+----------------+
-   * | F0         | 3             | 3                | 6              |
-   * +------------+---------------+------------------+----------------+
-   * | F4         | 4             | 4                | 8              |
-   * +------------+---------------+------------------+----------------+
-   */
-
-  /* df_ee_table[1] -> E0, df_ee_table[14] -> ED as ED - E0 = 13 */
-  // The values represent the adjustment in the Range Index table for a correct
-  // index.
-  const __m128i df_ee_table =
-      _mm_setr_epi8(0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0);
-
-  /* ef_fe_table[1] -> F0, ef_fe_table[5] -> F4, F4 - F0 = 4 */
-  // The values represent the adjustment in the Range Index table for a correct
-  // index.
-  const __m128i ef_fe_table =
-      _mm_setr_epi8(0, 3, 0, 0, 0, 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
-
-  __m128i prev_input = _mm_set1_epi8(0);
-  __m128i prev_first_len = _mm_set1_epi8(0);
-  __m128i error = _mm_set1_epi8(0);
-  while (end - data >= 16) {
-    const __m128i input =
-        _mm_loadu_si128((const __m128i*)(data));
-
-    /* high_nibbles = input >> 4 */
-    const __m128i high_nibbles =
-        _mm_and_si128(_mm_srli_epi16(input, 4), _mm_set1_epi8(0x0F));
-
-    /* first_len = legal character length minus 1 */
-    /* 0 for 00~7F, 1 for C0~DF, 2 for E0~EF, 3 for F0~FF */
-    /* first_len = first_len_table[high_nibbles] */
-    __m128i first_len = _mm_shuffle_epi8(first_len_table, high_nibbles);
-
-    /* First Byte: set range index to 8 for bytes within 0xC0 ~ 0xFF */
-    /* range = first_range_table[high_nibbles] */
-    __m128i range = _mm_shuffle_epi8(first_range_table, high_nibbles);
-
-    /* Second Byte: set range index to first_len */
-    /* 0 for 00~7F, 1 for C0~DF, 2 for E0~EF, 3 for F0~FF */
-    /* range |= (first_len, prev_first_len) << 1 byte */
-    range = _mm_or_si128(range, _mm_alignr_epi8(first_len, prev_first_len, 15));
-
-    /* Third Byte: set range index to saturate_sub(first_len, 1) */
-    /* 0 for 00~7F, 0 for C0~DF, 1 for E0~EF, 2 for F0~FF */
-    __m128i tmp1;
-    __m128i tmp2;
-    /* tmp1 = saturate_sub(first_len, 1) */
-    tmp1 = _mm_subs_epu8(first_len, _mm_set1_epi8(1));
-    /* tmp2 = saturate_sub(prev_first_len, 1) */
-    tmp2 = _mm_subs_epu8(prev_first_len, _mm_set1_epi8(1));
-    /* range |= (tmp1, tmp2) << 2 bytes */
-    range = _mm_or_si128(range, _mm_alignr_epi8(tmp1, tmp2, 14));
-
-    /* Fourth Byte: set range index to saturate_sub(first_len, 2) */
-    /* 0 for 00~7F, 0 for C0~DF, 0 for E0~EF, 1 for F0~FF */
-    /* tmp1 = saturate_sub(first_len, 2) */
-    tmp1 = _mm_subs_epu8(first_len, _mm_set1_epi8(2));
-    /* tmp2 = saturate_sub(prev_first_len, 2) */
-    tmp2 = _mm_subs_epu8(prev_first_len, _mm_set1_epi8(2));
-    /* range |= (tmp1, tmp2) << 3 bytes */
-    range = _mm_or_si128(range, _mm_alignr_epi8(tmp1, tmp2, 13));
-
-    /*
-     * Now we have below range indices calculated
-     * Correct cases:
-     * - 8 for C0~FF
-     * - 3 for 1st byte after F0~FF
-     * - 2 for 1st byte after E0~EF or 2nd byte after F0~FF
-     * - 1 for 1st byte after C0~DF or 2nd byte after E0~EF or
-     *         3rd byte after F0~FF
-     * - 0 for others
-     * Error cases:
-     *   >9 for non ascii First Byte overlapping
-     *   E.g., F1 80 C2 90 --> 8 3 10 2, where 10 indicates error
-     */
-
-    /* Adjust Second Byte range for special First Bytes(E0,ED,F0,F4) */
-    /* Overlaps lead to index 9~15, which are illegal in range table */
-    __m128i shift1;
-    __m128i pos;
-    __m128i range2;
-    /* shift1 = (input, prev_input) << 1 byte */
-    shift1 = _mm_alignr_epi8(input, prev_input, 15);
-    pos = _mm_sub_epi8(shift1, _mm_set1_epi8(0xEF));
-    /*
-     * shift1:  | EF  F0 ... FE | FF  00  ... ...  DE | DF  E0 ... EE |
-     * pos:     | 0   1      15 | 16  17           239| 240 241    255|
-     * pos-240: | 0   0      0  | 0   0            0  | 0   1      15 |
-     * pos+112: | 112 113    127|       >= 128        |     >= 128    |
-     */
-    tmp1 = _mm_subs_epu8(pos, _mm_set1_epi8(-16));
-    range2 = _mm_shuffle_epi8(df_ee_table, tmp1);
-    tmp2 = _mm_adds_epu8(pos, _mm_set1_epi8(112));
-    range2 = _mm_add_epi8(range2, _mm_shuffle_epi8(ef_fe_table, tmp2));
-
-    range = _mm_add_epi8(range, range2);
-
-    /* Load min and max values per calculated range index */
-    __m128i min_range = _mm_shuffle_epi8(range_min_table, range);
-    __m128i max_range = _mm_shuffle_epi8(range_max_table, range);
-
-    /* Check value range */
-    if (return_position) {
-      error = _mm_cmplt_epi8(input, min_range);
-      error = _mm_or_si128(error, _mm_cmpgt_epi8(input, max_range));
-      /* 5% performance drop from this conditional branch */
-      if (!_mm_testz_si128(error, error)) {
-        break;
-      }
-    } else {
-      error = _mm_or_si128(error, _mm_cmplt_epi8(input, min_range));
-      error = _mm_or_si128(error, _mm_cmpgt_epi8(input, max_range));
-    }
-
-    prev_input = input;
-    prev_first_len = first_len;
-
-    data += 16;
-  }
-  /* If we got to the end, we don't need to skip any bytes backwards */
-  if (return_position && (data - (end - len)) == 0) {
-    return utf8_range_ValidateUTF8Naive(data, end, return_position);
-  }
-  /* Find previous codepoint (not 80~BF) */
-  data -= utf8_range_CodepointSkipBackwards(_mm_extract_epi32(prev_input, 3));
-  if (return_position) {
-    return (data - (end - len)) +
-           utf8_range_ValidateUTF8Naive(data, end, return_position);
-  }
-  /* Test if there was any error */
-  if (!_mm_testz_si128(error, error)) {
-    return 0;
-  }
-  /* Check the tail */
-  return utf8_range_ValidateUTF8Naive(data, end, return_position);
 #endif
 }