Bug 1542736 - Part 3: Replace JS7_ISOCT and JS7_UNOCT macros with proper functions. r=jwalden

JS7_ISOCT and JS7_UNOCT were only used in TokenStream, so the new functions were
directly moved into that file instead of adding them to util/Text.h.

Differential Revision: https://phabricator.services.mozilla.com/D26506

--HG--
extra : moz-landing-system : lando

js/src/frontend/TokenStream.cpp

@@ -25,6 +25,7 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
+#include <type_traits>
 #include <utility>
 
 #include "jsexn.h"
@@ -165,6 +166,20 @@ static uint32_t GetSingleCodePoint(const char16_t** p, const char16_t* end) {
   return codePoint;
 }
 
+template <typename CharT>
+static constexpr bool IsAsciiOctal(CharT c) {
+  using UnsignedCharT = std::make_unsigned_t<CharT>;
+  auto uc = static_cast<UnsignedCharT>(c);
+  return '0' <= uc && uc <= '7';
+}
+
+template <typename CharT>
+static constexpr uint8_t AsciiOctalToNumber(CharT c) {
+  using UnsignedCharT = std::make_unsigned_t<CharT>;
+  auto uc = static_cast<UnsignedCharT>(c);
+  return uc - '0';
+}
+
 namespace js {
 
 namespace frontend {
@@ -2624,7 +2639,7 @@ MOZ_MUST_USE bool TokenStreamSpecific<Unit, AnyCharsAccess>::getTokenInternal(
       } else if (unit == 'o' || unit == 'O') {
         radix = 8;
         unit = getCodeUnit();
-        if (!JS7_ISOCT(unit)) {
+        if (!IsAsciiOctal(unit)) {
           // NOTE: |unit| may be EOF here.
           ungetCodeUnit(unit);
           error(JSMSG_MISSING_OCTAL_DIGITS);
@@ -2634,7 +2649,7 @@ MOZ_MUST_USE bool TokenStreamSpecific<Unit, AnyCharsAccess>::getTokenInternal(
         // one past the '0o'
         numStart = this->sourceUnits.addressOfNextCodeUnit() - 1;
 
-        while (JS7_ISOCT(unit)) {
+        while (IsAsciiOctal(unit)) {
           unit = getCodeUnit();
         }
       } else if (IsAsciiDigit(unit)) {
@@ -3263,12 +3278,12 @@ bool TokenStreamSpecific<Unit, AnyCharsAccess>::getStringOrTemplateToken(
         }
 
         default: {
-          if (!JS7_ISOCT(unit)) {
+          if (!IsAsciiOctal(unit)) {
             break;
           }
 
           // Octal character specification.
-          int32_t val = JS7_UNOCT(unit);
+          int32_t val = AsciiOctalToNumber(unit);
 
           unit = peekCodeUnit();
           if (MOZ_UNLIKELY(unit == EOF)) {
@@ -3290,8 +3305,8 @@ bool TokenStreamSpecific<Unit, AnyCharsAccess>::getStringOrTemplateToken(
             anyChars.flags.sawOctalEscape = true;
           }
 
-          if (JS7_ISOCT(unit)) {
-            val = 8 * val + JS7_UNOCT(unit);
+          if (IsAsciiOctal(unit)) {
+            val = 8 * val + AsciiOctalToNumber(unit);
             consumeKnownCodeUnit(unit);
 
             unit = peekCodeUnit();
@@ -3300,9 +3315,9 @@ bool TokenStreamSpecific<Unit, AnyCharsAccess>::getStringOrTemplateToken(
               return false;
             }
 
-            if (JS7_ISOCT(unit)) {
+            if (IsAsciiOctal(unit)) {
               int32_t save = val;
-              val = 8 * val + JS7_UNOCT(unit);
+              val = 8 * val + AsciiOctalToNumber(unit);
               if (val <= 0xFF) {
                 consumeKnownCodeUnit(unit);
               } else {

js/src/util/Text.h

@@ -33,8 +33,6 @@ class JSLinearString;
  * for us.
  */
 #define JS7_UNDEC(c) ((c) - '0')
-#define JS7_ISOCT(c) ((((unsigned)(c)) - '0') <= 7)
-#define JS7_UNOCT(c) (JS7_UNDEC(c))
 
 static MOZ_ALWAYS_INLINE size_t js_strlen(const char16_t* s) {
   return std::char_traits<char16_t>::length(s);