[regexp] Remove dead code

Remove dead code, and drop the legacy RegExp.prototype.exec implementation (the
only differences are TO_BOOLEAN on global and sticky).

BUG=v8:5339

Review-Url: https://codereview.chromium.org/2301803003
Cr-Commit-Position: refs/heads/master@{#39121}

src/js/regexp.js

@@ -162,46 +162,6 @@ function RegExpSubclassExecJS(string) {
 %FunctionRemovePrototype(RegExpSubclassExecJS);
 
 
-// Legacy implementation of RegExp.prototype.exec
-function RegExpExecJS(string) {
-  if (!IS_REGEXP(this)) {
-    throw %make_type_error(kIncompatibleMethodReceiver,
-                        'RegExp.prototype.exec', this);
-  }
-
-  string = TO_STRING(string);
-  var lastIndex = this.lastIndex;
-
-  // Conversion is required by the ES2015 specification (RegExpBuiltinExec
-  // algorithm, step 4) even if the value is discarded for non-global RegExps.
-  var i = TO_LENGTH(lastIndex);
-
-  var updateLastIndex = REGEXP_GLOBAL(this) || REGEXP_STICKY(this);
-  if (updateLastIndex) {
-    if (i < 0 || i > string.length) {
-      this.lastIndex = 0;
-      return null;
-    }
-  } else {
-    i = 0;
-  }
-
-  // matchIndices is either null or the RegExpLastMatchInfo array.
-  var matchIndices = %_RegExpExec(this, string, i, RegExpLastMatchInfo);
-
-  if (IS_NULL(matchIndices)) {
-    this.lastIndex = 0;
-    return null;
-  }
-
-  // Successful match.
-  if (updateLastIndex) {
-    this.lastIndex = RegExpLastMatchInfo[CAPTURE1];
-  }
-  RETURN_NEW_RESULT_FROM_MATCH_INFO(matchIndices, string);
-}
-
-
 // ES#sec-regexpexec Runtime Semantics: RegExpExec ( R, S )
 // Also takes an optional exec method in case our caller
 // has already fetched exec.
@@ -216,70 +176,11 @@ function RegExpSubclassExec(regexp, string, exec) {
     }
     return result;
   }
-  return %_Call(RegExpExecJS, regexp, string);
+  return %_Call(RegExpSubclassExecJS, regexp, string);
 }
 %SetForceInlineFlag(RegExpSubclassExec);
 
 
-// One-element cache for the simplified test regexp.
-var regexp_key;
-var regexp_val;
-
-// Legacy implementation of RegExp.prototype.test
-// Section 15.10.6.3 doesn't actually make sense, but the intention seems to be
-// that test is defined in terms of String.prototype.exec. However, it probably
-// means the original value of String.prototype.exec, which is what everybody
-// else implements.
-function RegExpTest(string) {
-  if (!IS_REGEXP(this)) {
-    throw %make_type_error(kIncompatibleMethodReceiver,
-                        'RegExp.prototype.test', this);
-  }
-  string = TO_STRING(string);
-
-  var lastIndex = this.lastIndex;
-
-  // Conversion is required by the ES2015 specification (RegExpBuiltinExec
-  // algorithm, step 4) even if the value is discarded for non-global RegExps.
-  var i = TO_LENGTH(lastIndex);
-
-  if (REGEXP_GLOBAL(this) || REGEXP_STICKY(this)) {
-    if (i < 0 || i > string.length) {
-      this.lastIndex = 0;
-      return false;
-    }
-    // matchIndices is either null or the RegExpLastMatchInfo array.
-    var matchIndices = %_RegExpExec(this, string, i, RegExpLastMatchInfo);
-    if (IS_NULL(matchIndices)) {
-      this.lastIndex = 0;
-      return false;
-    }
-    this.lastIndex = RegExpLastMatchInfo[CAPTURE1];
-    return true;
-  } else {
-    // Non-global, non-sticky regexp.
-    // Remove irrelevant preceeding '.*' in a test regexp.  The expression
-    // checks whether this.source starts with '.*' and that the third char is
-    // not a '?'.  But see https://code.google.com/p/v8/issues/detail?id=3560
-    var regexp = this;
-    var source = REGEXP_SOURCE(regexp);
-    if (source.length >= 3 &&
-        %_StringCharCodeAt(source, 0) == 46 &&  // '.'
-        %_StringCharCodeAt(source, 1) == 42 &&  // '*'
-        %_StringCharCodeAt(source, 2) != 63) {  // '?'
-      regexp = TrimRegExp(regexp);
-    }
-    // matchIndices is either null or the RegExpLastMatchInfo array.
-    var matchIndices = %_RegExpExec(regexp, string, 0, RegExpLastMatchInfo);
-    if (IS_NULL(matchIndices)) {
-      this.lastIndex = 0;
-      return false;
-    }
-    return true;
-  }
-}
-
-
 // ES#sec-regexp.prototype.test RegExp.prototype.test ( S )
 function RegExpSubclassTest(string) {
   if (!IS_RECEIVER(this)) {
@@ -292,18 +193,6 @@ function RegExpSubclassTest(string) {
 }
 %FunctionRemovePrototype(RegExpSubclassTest);
 
-function TrimRegExp(regexp) {
-  if (regexp_key !== regexp) {
-    regexp_key = regexp;
-    regexp_val =
-      new GlobalRegExp(
-          %_SubString(REGEXP_SOURCE(regexp), 2, REGEXP_SOURCE(regexp).length),
-          (REGEXP_IGNORE_CASE(regexp) ? REGEXP_MULTILINE(regexp) ? "im" : "i"
-                                      : REGEXP_MULTILINE(regexp) ? "m" : ""));
-  }
-  return regexp_val;
-}
-
 
 function AtSurrogatePair(subject, index) {
   if (index + 1 >= subject.length) return false;
@@ -927,10 +816,7 @@ utils.Export(function(to) {
   to.InternalRegExpMatch = InternalRegExpMatch;
   to.InternalRegExpReplace = InternalRegExpReplace;
   to.IsRegExp = IsRegExp;
-  to.RegExpExec = DoRegExpExec;
   to.RegExpInitialize = RegExpInitialize;
-  to.RegExpLastMatchInfo = RegExpLastMatchInfo;
-  to.RegExpTest = RegExpTest;
 });
 
 })