MIRROR: javascript for 🐜's, a tiny runtime with big ambitions
optimize number fast paths
+38
-23
+38
-23
src/numbers.cc
+38
-23
src/numbers.cc
···
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static constexpr size_t kExponentialBufferSize =
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DoubleToStringConverter::kMaxExponentialDigits + 8 + 1;
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+
static const StringToDoubleConverter kDecimalStringConverter(
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0, 0.0,
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std::numeric_limits<double>::quiet_NaN(),
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"Infinity", "NaN"
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);
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+
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static const StringToDoubleConverter kJsNumberStringConverter(
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StringToDoubleConverter::ALLOW_HEX, 0.0,
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std::numeric_limits<double>::quiet_NaN(),
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"Infinity", "NaN"
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);
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+
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+
static const StringToDoubleConverter kParseFloatStringConverter(
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StringToDoubleConverter::ALLOW_TRAILING_JUNK, 0.0,
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std::numeric_limits<double>::quiet_NaN(),
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"Infinity", "NaN"
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+
);
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+
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+
static bool is_ascii_js_string_trim_byte(unsigned char ch) {
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return
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ch == ' ' || ch == '\t' || ch == '\n' ||
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ch == '\v' || ch == '\f' || ch == '\r';
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}
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+
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#define JS_TRIM_TOKEN(bytes) { bytes, sizeof(bytes) - 1 }
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static constexpr JsTrimToken kJsStringTrimTokens[] = {
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JS_TRIM_TOKEN("\t"),
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JS_TRIM_TOKEN("\n"),
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JS_TRIM_TOKEN("\v"),
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JS_TRIM_TOKEN("\f"),
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JS_TRIM_TOKEN("\r"),
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JS_TRIM_TOKEN(" "),
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JS_TRIM_TOKEN("\xc2""\xa0"),
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JS_TRIM_TOKEN("\xe1""\x9a""\x80"),
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JS_TRIM_TOKEN("\xe2""\x80""\x80"),
···
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#undef JS_TRIM_TOKEN
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static size_t js_string_trim_prefix_len(const char *str, size_t len) {
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if (len == 0) return 0;
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+
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unsigned char first = (unsigned char)str[0];
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if (first < 0x80) return is_ascii_js_string_trim_byte(first) ? 1 : 0;
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+
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for (const JsTrimToken &token : kJsStringTrimTokens)
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if (len >= token.len && std::memcmp(str, token.bytes, token.len) == 0) return token.len;
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return 0;
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}
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static size_t js_string_trim_suffix_len(const char *str, size_t len) {
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if (len == 0) return 0;
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+
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unsigned char last = (unsigned char)str[len - 1];
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if (last < 0x80) return is_ascii_js_string_trim_byte(last) ? 1 : 0;
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+
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for (const JsTrimToken &token : kJsStringTrimTokens)
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if (len >= token.len && std::memcmp(str + len - token.len, token.bytes, token.len) == 0) return token.len;
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return 0;
···
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return true;
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}
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-
int flags = 0;
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if (mode == ANT_NUMBER_PARSE_JS_NUMBER)
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flags =
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StringToDoubleConverter::ALLOW_HEX |
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StringToDoubleConverter::ALLOW_LEADING_SPACES |
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StringToDoubleConverter::ALLOW_TRAILING_SPACES;
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else if (mode == ANT_NUMBER_PARSE_FLOAT_PREFIX)
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flags =
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StringToDoubleConverter::ALLOW_LEADING_SPACES |
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StringToDoubleConverter::ALLOW_TRAILING_JUNK;
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StringToDoubleConverter converter(
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flags, 0.0,
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std::numeric_limits<double>::quiet_NaN(),
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"Infinity", "NaN"
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);
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const StringToDoubleConverter *converter = &kDecimalStringConverter;
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if (mode == ANT_NUMBER_PARSE_JS_NUMBER) converter = &kJsNumberStringConverter;
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else if (mode == ANT_NUMBER_PARSE_FLOAT_PREFIX) converter = &kParseFloatStringConverter;
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int count = 0;
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double value = converter.StringToDouble(str, (int)len, &count);
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double value = converter->StringToDouble(str, (int)len, &count);
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if (count <= 0) return false;
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if (mode != ANT_NUMBER_PARSE_FLOAT_PREFIX && (size_t)count != len) return false;