Bug 784608 (part 7) - Change the form and meaning of ParseContext::innermostWith, and do follow-up simplifications. r=luke.

--HG--
extra : rebase_source : 035c8976f4767235c5f88f0440401c668c7676a8

js/src/frontend/BytecodeEmitter.cpp

@@ -1686,10 +1686,8 @@ BytecodeEmitter::needsImplicitThis()
         return true;
 
     if (sc->inFunction()) {
-        for (const FunctionBox *funbox = this->sc->funbox(); funbox; funbox = funbox->parent) {
-            if (funbox->inWith)
-                return true;
-        }
+        if (sc->funbox()->inWith)
+            return true;
     } else {
         JSObject *scope = sc->scopeChain();
         while (scope) {

js/src/frontend/Parser-inl.h

@@ -46,11 +46,11 @@ ParseContext::ParseContext(Parser *prs, SharedContext *sc, unsigned staticLevel,
     parserPC(&prs->pc),
     lexdeps(prs->context),
     parent(prs->pc),
-    innermostWith(NULL),
     funcStmts(NULL),
     funHasReturnExpr(false),
     funHasReturnVoid(false),
     parsingForInit(false),
+    parsingWith(prs->pc ? prs->pc->parsingWith : false), // inherit from parent context
     inDeclDestructuring(false)
 {
     prs->pc = this;

js/src/frontend/Parser.cpp

@@ -398,7 +398,7 @@ FunctionBox::FunctionBox(ObjectBox* traceListHead, JSObject *obj, ParseContext *
     bufEnd(0),
     ndefaults(0),
     strictModeState(sms),
-    inWith(!!outerpc->innermostWith),
+    inWith(outerpc->parsingWith),
     inGenexpLambda(false),
     cxFlags(outerpc->sc->context)     // the cxFlags are set in LeaveFunction
 {
@@ -1151,7 +1151,7 @@ LeaveFunction(ParseNode *fn, Parser *parser, PropertyName *funName = NULL,
              * by eval and function statements (which both flag the function as
              * having an extensible scope) or any enclosing 'with'.
              */
-            if (funpc->sc->funHasExtensibleScope() || pc->innermostWith)
+            if (funpc->sc->funHasExtensibleScope() || pc->parsingWith)
                 DeoptimizeUsesWithin(dn, fn->pn_pos);
 
             if (!outer_dn) {
@@ -3482,8 +3482,8 @@ Parser::withStatement()
     MUST_MATCH_TOKEN(TOK_RP, JSMSG_PAREN_AFTER_WITH);
     pn->pn_left = pn2;
 
-    ParseNode *oldWith = pc->innermostWith;
-    pc->innermostWith = pn;
+    bool oldParsingWith = pc->parsingWith;
+    pc->parsingWith = true;
 
     StmtInfoPC stmtInfo(context);
     PushStatementPC(pc, &stmtInfo, STMT_WITH);
@@ -3496,7 +3496,7 @@ Parser::withStatement()
     pn->pn_right = pn2;
 
     pc->sc->setBindingsAccessedDynamically();
-    pc->innermostWith = oldWith;
+    pc->parsingWith = oldParsingWith;
 
     /*
      * Make sure to deoptimize lexical dependencies inside the |with|
@@ -5523,8 +5523,8 @@ Parser::memberExpr(bool allowCallSyntax)
                     pc->sc->setBindingsAccessedDynamically();
 
                     StmtInfoPC stmtInfo(context);
-                    ParseNode *oldWith = pc->innermostWith;
-                    pc->innermostWith = lhs;
+                    bool oldParsingWith = pc->parsingWith;
+                    pc->parsingWith = true;
                     PushStatementPC(pc, &stmtInfo, STMT_WITH);
 
                     ParseNode *filter = bracketedExpr();
@@ -5533,7 +5533,7 @@ Parser::memberExpr(bool allowCallSyntax)
                     filter->setInParens(true);
                     MUST_MATCH_TOKEN(TOK_RP, JSMSG_PAREN_IN_PAREN);
 
-                    pc->innermostWith = oldWith;
+                    pc->parsingWith = oldParsingWith;
                     PopStatementPC(context, pc);
 
                     nextMember =

js/src/frontend/Parser.h

@@ -174,8 +174,6 @@ struct ParseContext                 /* tree context for semantic checks */
 
     ParseContext     *parent;       /* Enclosing function or global context.  */
 
-    ParseNode       *innermostWith; /* innermost WITH parse node */
-
     FuncStmtSet     *funcStmts;     /* Set of (non-top-level) function statements
                                        that will alias any top-level bindings with
                                        the same name. */
@@ -189,6 +187,9 @@ struct ParseContext                 /* tree context for semantic checks */
     // source code, and cleared when that region is exited.
     bool            parsingForInit:1;   /* true while parsing init expr of for;
                                            exclude 'in' */
+    bool            parsingWith:1;  /* true while we are within a
+                                       with-statement or E4X filter-expression
+                                       in the current ParseContext chain */
 
     // Set when parsing a declaration-like destructuring pattern.  This flag
     // causes PrimaryExpr to create PN_NAME parse nodes for variable references