ParseNode*
ParseNode::appendOrCreateList(ParseNodeKind kind, JSOp op, ParseNode* left, ParseNode* right,
FullParseHandler* handler, ParseContext<FullParseHandler>* pc)
{
// The asm.js specification is written in ECMAScript grammar terms that
// specify *only* a binary tree. It's a royal pain to implement the asm.js
// spec to act upon n-ary lists as created below. So for asm.js, form a
// binary tree of lists exactly as ECMAScript would by skipping the
// following optimization.
if (!pc->useAsmOrInsideUseAsm()) {
// Left-associative trees of a given operator (e.g. |a + b + c|) are
// binary trees in the spec: (+ (+ a b) c) in Lisp terms. Recursively
// processing such a tree, exactly implemented that way, would blow the
// the stack. We use a list node that uses O(1) stack to represent
// such operations: (+ a b c).
if (left->isKind(kind) && left->isOp(op) && (js_CodeSpec[op].format & JOF_LEFTASSOC)) {
ListNode* list = &left->as<ListNode>();
list->append(right);
list->pn_pos.end = right->pn_pos.end;
return list;
}
}
ParseNode* list = handler->new_<ListNode>(kind, op, left);
if (!list)
return nullptr;
list->append(right);
return list;
}
/*
* Used by Parser::forStatement and comprehensionTail to clone the TARGET in
* for (var/const/let TARGET in EXPR)
*
* opn must be the pn_head of a node produced by Parser::variables, so its form
* is known to be LHS = NAME | [LHS] | {id:LHS}.
*
* The cloned tree is for use only in the same statement and binding context as
* the original tree.
*/
ParseNode *
js::CloneLeftHandSide(ParseNode *opn, Parser *parser)
{
ParseNode *pn = parser->new_<ParseNode>(opn->getKind(), opn->getOp(), opn->getArity(),
opn->pn_pos);
if (!pn)
return NULL;
pn->setInParens(opn->isInParens());
pn->setDefn(opn->isDefn());
pn->setUsed(opn->isUsed());
#if JS_HAS_DESTRUCTURING
if (opn->isArity(PN_LIST)) {
JS_ASSERT(opn->isKind(PNK_RB) || opn->isKind(PNK_RC));
pn->makeEmpty();
for (ParseNode *opn2 = opn->pn_head; opn2; opn2 = opn2->pn_next) {
ParseNode *pn2;
if (opn->isKind(PNK_RC)) {
JS_ASSERT(opn2->isArity(PN_BINARY));
JS_ASSERT(opn2->isKind(PNK_COLON));
ParseNode *tag = CloneParseTree(opn2->pn_left, parser);
if (!tag)
return NULL;
ParseNode *target = CloneLeftHandSide(opn2->pn_right, parser);
if (!target)
return NULL;
pn2 = parser->new_<BinaryNode>(PNK_COLON, JSOP_INITPROP, opn2->pn_pos, tag, target);
} else if (opn2->isArity(PN_NULLARY)) {
JS_ASSERT(opn2->isKind(PNK_COMMA));
pn2 = CloneParseTree(opn2, parser);
} else {
pn2 = CloneLeftHandSide(opn2, parser);
}
if (!pn2)
return NULL;
pn->append(pn2);
}
pn->pn_xflags = opn->pn_xflags;
return pn;
}
#endif
JS_ASSERT(opn->isArity(PN_NAME));
JS_ASSERT(opn->isKind(PNK_NAME));
/* If opn is a definition or use, make pn a use. */
pn->pn_u.name = opn->pn_u.name;
pn->setOp(JSOP_SETNAME);
if (opn->isUsed()) {
Definition *dn = pn->pn_lexdef;
pn->pn_link = dn->dn_uses;
dn->dn_uses = pn;
} else {
pn->pn_expr = NULL;
if (opn->isDefn()) {
/* We copied some definition-specific state into pn. Clear it out. */
pn->pn_cookie.makeFree();
pn->pn_dflags &= ~PND_BOUND;
pn->setDefn(false);
LinkUseToDef(pn, (Definition *) opn);
}
}
return pn;
}
/*
* This function assumes the cloned tree is for use in the same statement and
* binding context as the original tree.
*/
static ParseNode *
CloneParseTree(ParseNode *opn, Parser *parser)
{
TreeContext *tc = parser->tc;
JS_CHECK_RECURSION(tc->sc->context, return NULL);
ParseNode *pn = parser->new_<ParseNode>(opn->getKind(), opn->getOp(), opn->getArity(),
opn->pn_pos);
if (!pn)
return NULL;
pn->setInParens(opn->isInParens());
pn->setDefn(opn->isDefn());
pn->setUsed(opn->isUsed());
switch (pn->getArity()) {
#define NULLCHECK(e) JS_BEGIN_MACRO if (!(e)) return NULL; JS_END_MACRO
case PN_FUNC:
NULLCHECK(pn->pn_funbox =
parser->newFunctionBox(opn->pn_funbox->object, pn, tc, opn->pn_funbox->strictModeState));
NULLCHECK(pn->pn_body = CloneParseTree(opn->pn_body, parser));
pn->pn_cookie = opn->pn_cookie;
pn->pn_dflags = opn->pn_dflags;
pn->pn_blockid = opn->pn_blockid;
break;
case PN_LIST:
pn->makeEmpty();
for (ParseNode *opn2 = opn->pn_head; opn2; opn2 = opn2->pn_next) {
ParseNode *pn2;
NULLCHECK(pn2 = CloneParseTree(opn2, parser));
pn->append(pn2);
}
pn->pn_xflags = opn->pn_xflags;
break;
case PN_TERNARY:
NULLCHECK(pn->pn_kid1 = CloneParseTree(opn->pn_kid1, parser));
NULLCHECK(pn->pn_kid2 = CloneParseTree(opn->pn_kid2, parser));
NULLCHECK(pn->pn_kid3 = CloneParseTree(opn->pn_kid3, parser));
break;
case PN_BINARY:
NULLCHECK(pn->pn_left = CloneParseTree(opn->pn_left, parser));
if (opn->pn_right != opn->pn_left)
NULLCHECK(pn->pn_right = CloneParseTree(opn->pn_right, parser));
else
pn->pn_right = pn->pn_left;
pn->pn_pval = opn->pn_pval;
pn->pn_iflags = opn->pn_iflags;
break;
case PN_UNARY:
NULLCHECK(pn->pn_kid = CloneParseTree(opn->pn_kid, parser));
pn->pn_hidden = opn->pn_hidden;
break;
case PN_NAME:
// PN_NAME could mean several arms in pn_u, so copy the whole thing.
pn->pn_u = opn->pn_u;
if (opn->isUsed()) {
/*
* The old name is a use of its pn_lexdef. Make the clone also be a
* use of that definition.
*/
Definition *dn = pn->pn_lexdef;
pn->pn_link = dn->dn_uses;
dn->dn_uses = pn;
} else if (opn->pn_expr) {
NULLCHECK(pn->pn_expr = CloneParseTree(opn->pn_expr, parser));
/*
* If the old name is a definition, the new one has pn_defn set.
* Make the old name a use of the new node.
*/
if (opn->isDefn()) {
opn->setDefn(false);
LinkUseToDef(opn, (Definition *) pn);
}
}
break;
case PN_NAMESET:
pn->pn_names = opn->pn_names;
NULLCHECK(pn->pn_tree = CloneParseTree(opn->pn_tree, parser));
break;
case PN_NULLARY:
// Even PN_NULLARY may have data (xmlpi for E4X -- what a botch).
pn->pn_u = opn->pn_u;
break;
#undef NULLCHECK
}
return pn;
}
