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-rw-r--r--js/src/builtin/TypedArray.js4
-rw-r--r--js/src/frontend/BytecodeEmitter.cpp619
-rw-r--r--js/src/frontend/BytecodeEmitter.h6
-rw-r--r--js/src/jit/JitFrames.cpp39
-rw-r--r--js/src/js.msg2
-rw-r--r--js/src/jsiter.cpp52
-rw-r--r--js/src/jsiter.h3
-rw-r--r--js/src/jsscript.h3
-rw-r--r--js/src/shell/js.cpp9
-rw-r--r--js/src/tests/ecma_6/Statements/for-of-iterator-close.js102
-rw-r--r--js/src/tests/ecma_6/shell.js48
-rw-r--r--js/src/vm/Interpreter.cpp19
-rw-r--r--js/src/vm/Interpreter.h1
13 files changed, 704 insertions, 203 deletions
diff --git a/js/src/builtin/TypedArray.js b/js/src/builtin/TypedArray.js
index 4a3f38365..a2205dc92 100644
--- a/js/src/builtin/TypedArray.js
+++ b/js/src/builtin/TypedArray.js
@@ -1428,7 +1428,7 @@ function TypedArrayStaticFrom(source, mapfn = undefined, thisArg = undefined) {
// 22.2.2.1.1 IterableToList, step 4.a.
var next = callContentFunction(iterator.next, iterator);
if (!IsObject(next))
- ThrowTypeError(JSMSG_NEXT_RETURNED_PRIMITIVE);
+ ThrowTypeError(JSMSG_ITER_METHOD_RETURNED_PRIMITIVE, "next");
// 22.2.2.1.1 IterableToList, step 4.b.
if (next.done)
@@ -1555,7 +1555,7 @@ function IterableToList(items, method) {
// Step 4.a.
var next = callContentFunction(iterator.next, iterator);
if (!IsObject(next))
- ThrowTypeError(JSMSG_NEXT_RETURNED_PRIMITIVE);
+ ThrowTypeError(JSMSG_ITER_METHOD_RETURNED_PRIMITIVE, "next");
// Step 4.b.
if (next.done)
diff --git a/js/src/frontend/BytecodeEmitter.cpp b/js/src/frontend/BytecodeEmitter.cpp
index a4cfeb753..fb141e92d 100644
--- a/js/src/frontend/BytecodeEmitter.cpp
+++ b/js/src/frontend/BytecodeEmitter.cpp
@@ -58,6 +58,7 @@ using mozilla::Some;
class BreakableControl;
class LabelControl;
class LoopControl;
+class ForOfLoopControl;
class TryFinallyControl;
static bool
@@ -152,6 +153,13 @@ BytecodeEmitter::NestableControl::is<LoopControl>() const
template <>
bool
+BytecodeEmitter::NestableControl::is<ForOfLoopControl>() const
+{
+ return kind_ == StatementKind::ForOfLoop;
+}
+
+template <>
+bool
BytecodeEmitter::NestableControl::is<TryFinallyControl>() const
{
return kind_ == StatementKind::Try || kind_ == StatementKind::Finally;
@@ -270,6 +278,64 @@ class LoopControl : public BreakableControl
}
};
+class ForOfLoopControl : public LoopControl
+{
+ // The stack depth of the iterator.
+ int32_t iterDepth_;
+
+ // for-of loops, when throwing from non-iterator code (i.e. from the body
+ // or from evaluating the LHS of the loop condition), need to call
+ // IteratorClose. If IteratorClose itself throws, we must not re-call
+ // IteratorClose. Since non-local jumps like break and return call
+ // IteratorClose, whenever a non-local jump is emitted, we must terminate
+ // the current JSTRY_ITERCLOSE note to skip the non-local jump code, then
+ // start a new one.
+ //
+ // Visually,
+ //
+ // for (x of y) {
+ // ... instantiate ForOfLoopControl
+ // ... + <-- iterCloseTryStart_ points to right before
+ // ... assignment to loop variable
+ // ... ^
+ // ... |
+ // if (...) v
+ // + call finishIterCloseTryNote before |break|
+ // above range is noted with JSTRY_ITERCLOSE
+ //
+ // break; <-- break and IteratorClose are not inside
+ // JSTRY_ITERCLOSE note
+ //
+ // call startNewIterCloseTryNote after |break|
+ // + <-- next iterCloseTryStart_ points here
+ // ... |
+ // ... ~
+ // }
+ ptrdiff_t iterCloseTryStart_;
+
+ public:
+ ForOfLoopControl(BytecodeEmitter* bce, int32_t iterDepth)
+ : LoopControl(bce, StatementKind::ForOfLoop),
+ iterDepth_(iterDepth),
+ iterCloseTryStart_(-1)
+ {
+ MOZ_ASSERT(bce->stackDepth >= iterDepth);
+ }
+
+ MOZ_MUST_USE bool finishIterCloseTryNote(BytecodeEmitter* bce) {
+ ptrdiff_t end = bce->offset();
+ MOZ_ASSERT(end >= iterCloseTryStart_);
+ if (end != iterCloseTryStart_)
+ return bce->tryNoteList.append(JSTRY_ITERCLOSE, iterDepth_, iterCloseTryStart_, end);
+ return true;
+ }
+
+ void startNewIterCloseTryNote(BytecodeEmitter* bce) {
+ MOZ_ASSERT(bce->offset() > iterCloseTryStart_);
+ iterCloseTryStart_ = bce->offset();
+ }
+};
+
class TryFinallyControl : public BytecodeEmitter::NestableControl
{
bool emittingSubroutine_;
@@ -1497,6 +1563,156 @@ BytecodeEmitter::TDZCheckCache::noteTDZCheck(BytecodeEmitter* bce, JSAtom* name,
return true;
}
+class MOZ_STACK_CLASS IfThenElseEmitter
+{
+ BytecodeEmitter* bce_;
+ JumpList jumpAroundThen_;
+ JumpList jumpsAroundElse_;
+ unsigned noteIndex_;
+ int32_t thenDepth_;
+#ifdef DEBUG
+ int32_t pushed_;
+ bool calculatedPushed_;
+#endif
+ enum State {
+ Start,
+ If,
+ Cond,
+ IfElse,
+ Else,
+ End
+ };
+ State state_;
+
+ public:
+ explicit IfThenElseEmitter(BytecodeEmitter* bce)
+ : bce_(bce),
+ noteIndex_(-1),
+ thenDepth_(0),
+#ifdef DEBUG
+ pushed_(0),
+ calculatedPushed_(false),
+#endif
+ state_(Start)
+ {}
+
+ ~IfThenElseEmitter()
+ {}
+
+ private:
+ bool emitIf(State nextState) {
+ MOZ_ASSERT(state_ == Start || state_ == Else);
+ MOZ_ASSERT(nextState == If || nextState == IfElse || nextState == Cond);
+
+ // Clear jumpAroundThen_ offset that points previous JSOP_IFEQ.
+ if (state_ == Else)
+ jumpAroundThen_ = JumpList();
+
+ // Emit an annotated branch-if-false around the then part.
+ SrcNoteType type = nextState == If ? SRC_IF : nextState == IfElse ? SRC_IF_ELSE : SRC_COND;
+ if (!bce_->newSrcNote(type, &noteIndex_))
+ return false;
+ if (!bce_->emitJump(JSOP_IFEQ, &jumpAroundThen_))
+ return false;
+
+ // To restore stack depth in else part, save depth of the then part.
+#ifdef DEBUG
+ // If DEBUG, this is also necessary to calculate |pushed_|.
+ thenDepth_ = bce_->stackDepth;
+#else
+ if (nextState == IfElse || nextState == Cond)
+ thenDepth_ = bce_->stackDepth;
+#endif
+ state_ = nextState;
+ return true;
+ }
+
+ public:
+ bool emitIf() {
+ return emitIf(If);
+ }
+
+ bool emitCond() {
+ return emitIf(Cond);
+ }
+
+ bool emitIfElse() {
+ return emitIf(IfElse);
+ }
+
+ bool emitElse() {
+ MOZ_ASSERT(state_ == IfElse || state_ == Cond);
+
+ calculateOrCheckPushed();
+
+ // Emit a jump from the end of our then part around the else part. The
+ // patchJumpsToTarget call at the bottom of this function will fix up
+ // the offset with jumpsAroundElse value.
+ if (!bce_->emitJump(JSOP_GOTO, &jumpsAroundElse_))
+ return false;
+
+ // Ensure the branch-if-false comes here, then emit the else.
+ if (!bce_->emitJumpTargetAndPatch(jumpAroundThen_))
+ return false;
+
+ // Annotate SRC_IF_ELSE or SRC_COND with the offset from branch to
+ // jump, for IonMonkey's benefit. We can't just "back up" from the pc
+ // of the else clause, because we don't know whether an extended
+ // jump was required to leap from the end of the then clause over
+ // the else clause.
+ if (!bce_->setSrcNoteOffset(noteIndex_, 0,
+ jumpsAroundElse_.offset - jumpAroundThen_.offset))
+ {
+ return false;
+ }
+
+ // Restore stack depth of the then part.
+ bce_->stackDepth = thenDepth_;
+ state_ = Else;
+ return true;
+ }
+
+ bool emitEnd() {
+ MOZ_ASSERT(state_ == If || state_ == Else);
+
+ calculateOrCheckPushed();
+
+ if (state_ == If) {
+ // No else part, fixup the branch-if-false to come here.
+ if (!bce_->emitJumpTargetAndPatch(jumpAroundThen_))
+ return false;
+ }
+
+ // Patch all the jumps around else parts.
+ if (!bce_->emitJumpTargetAndPatch(jumpsAroundElse_))
+ return false;
+
+ state_ = End;
+ return true;
+ }
+
+ void calculateOrCheckPushed() {
+#ifdef DEBUG
+ if (!calculatedPushed_) {
+ pushed_ = bce_->stackDepth - thenDepth_;
+ calculatedPushed_ = true;
+ } else {
+ MOZ_ASSERT(pushed_ == bce_->stackDepth - thenDepth_);
+ }
+#endif
+ }
+
+#ifdef DEBUG
+ int32_t pushed() const {
+ return pushed_;
+ }
+
+ int32_t popped() const {
+ return -pushed_;
+ }
+#endif
+};
+
BytecodeEmitter::BytecodeEmitter(BytecodeEmitter* parent,
Parser<FullParseHandler>* parser, SharedContext* sc,
HandleScript script, Handle<LazyScript*> lazyScript,
@@ -2013,22 +2229,43 @@ BytecodeEmitter::flushPops(int* npops)
namespace {
-class NonLocalExitControl {
+class NonLocalExitControl
+{
+ public:
+ enum Kind
+ {
+ // IteratorClose is handled especially inside the exception unwinder.
+ Throw,
+
+ // A 'continue' statement does not call IteratorClose for the loop it
+ // is continuing, i.e. excluding the target loop.
+ Continue,
+
+ // A 'break' or 'return' statement does call IteratorClose for the
+ // loop it is breaking out of or returning from, i.e. including the
+ // target loop.
+ Break,
+ Return
+ };
+
+ private:
BytecodeEmitter* bce_;
const uint32_t savedScopeNoteIndex_;
const int savedDepth_;
uint32_t openScopeNoteIndex_;
+ Kind kind_;
NonLocalExitControl(const NonLocalExitControl&) = delete;
MOZ_MUST_USE bool leaveScope(BytecodeEmitter::EmitterScope* scope);
public:
- explicit NonLocalExitControl(BytecodeEmitter* bce)
+ NonLocalExitControl(BytecodeEmitter* bce, Kind kind)
: bce_(bce),
savedScopeNoteIndex_(bce->scopeNoteList.length()),
savedDepth_(bce->stackDepth),
- openScopeNoteIndex_(bce->innermostEmitterScope->noteIndex())
+ openScopeNoteIndex_(bce->innermostEmitterScope->noteIndex()),
+ kind_(kind)
{ }
~NonLocalExitControl() {
@@ -2075,6 +2312,14 @@ NonLocalExitControl::prepareForNonLocalJump(BytecodeEmitter::NestableControl* ta
EmitterScope* es = bce_->innermostEmitterScope;
int npops = 0;
+ bool hasForOfLoopsWithIteratorClose = false;
+
+ // IteratorClose is handled specially in the exception unwinder. For
+ // 'continue', 'break', and 'return' statements, emit IteratorClose
+ // bytecode inline. 'continue' statements do not call IteratorClose for
+ // the loop they are continuing.
+ bool emitIteratorClose = kind_ == Continue || kind_ == Break || kind_ == Return;
+ bool emitIteratorCloseAtTarget = emitIteratorClose && kind_ != Continue;
auto flushPops = [&npops](BytecodeEmitter* bce) {
if (npops && !bce->flushPops(&npops))
@@ -2114,15 +2359,29 @@ NonLocalExitControl::prepareForNonLocalJump(BytecodeEmitter::NestableControl* ta
}
case StatementKind::ForOfLoop:
- npops += 2;
+ // The iterator and the current value are on the stack.
+ //
+ if (emitIteratorClose) {
+ hasForOfLoopsWithIteratorClose = true;
+ if (!control->as<ForOfLoopControl>().finishIterCloseTryNote(bce_))
+ return false;
+ if (!bce_->emit1(JSOP_POP)) // ... ITER
+ return false;
+ if (!bce_->emitIteratorClose()) // ...
+ return false;
+ } else {
+ if (!bce_->emit1(JSOP_POP)) // ... ITER
+ return false;
+ if (!bce_->emit1(JSOP_POP)) // ...
+ return false;
+ }
break;
case StatementKind::ForInLoop:
- /* The iterator and the current value are on the stack. */
- npops += 1;
- if (!flushPops(bce_))
+ // The iterator and the current value are on the stack.
+ if (!bce_->emit1(JSOP_POP)) // ... ITER
return false;
- if (!bce_->emit1(JSOP_ENDITER))
+ if (!bce_->emit1(JSOP_ENDITER)) // ...
return false;
break;
@@ -2131,13 +2390,45 @@ NonLocalExitControl::prepareForNonLocalJump(BytecodeEmitter::NestableControl* ta
}
}
+ if (target && target->is<ForOfLoopControl>() && emitIteratorCloseAtTarget) {
+ hasForOfLoopsWithIteratorClose = true;
+ if (!target->as<ForOfLoopControl>().finishIterCloseTryNote(bce_))
+ return false;
+
+ // The iterator and the current value are on the stack. At the level
+ // of the target block, there's bytecode after the loop that will pop
+ // the iterator and the value, so duplicate the iterator and call
+ // IteratorClose.
+ if (!bce_->emitDupAt(1)) // ... ITER RESULT ITER
+ return false;
+ if (!bce_->emitIteratorClose()) // ... ITER RESULT
+ return false;
+ }
+
EmitterScope* targetEmitterScope = target ? target->emitterScope() : bce_->varEmitterScope;
for (; es != targetEmitterScope; es = es->enclosingInFrame()) {
if (!leaveScope(es))
return false;
}
- return flushPops(bce_);
+ if (!flushPops(bce_))
+ return false;
+
+ // See comment in ForOfLoopControl.
+ if (hasForOfLoopsWithIteratorClose) {
+ for (NestableControl* control = bce_->innermostNestableControl;
+ control != target;
+ control = control->enclosing())
+ {
+ if (control->is<ForOfLoopControl>())
+ control->as<ForOfLoopControl>().startNewIterCloseTryNote(bce_);
+ }
+
+ if (target && target->is<ForOfLoopControl>() && emitIteratorCloseAtTarget)
+ target->as<ForOfLoopControl>().startNewIterCloseTryNote(bce_);
+ }
+
+ return true;
}
} // anonymous namespace
@@ -2145,7 +2436,9 @@ NonLocalExitControl::prepareForNonLocalJump(BytecodeEmitter::NestableControl* ta
bool
BytecodeEmitter::emitGoto(NestableControl* target, JumpList* jumplist, SrcNoteType noteType)
{
- NonLocalExitControl nle(this);
+ NonLocalExitControl nle(this, noteType == SRC_CONTINUE
+ ? NonLocalExitControl::Continue
+ : NonLocalExitControl::Break);
if (!nle.prepareForNonLocalJump(target))
return false;
@@ -4530,6 +4823,144 @@ BytecodeEmitter::emitIteratorNext(ParseNode* pn, bool allowSelfHosted)
}
bool
+BytecodeEmitter::emitIteratorClose(Maybe<JumpTarget> yieldStarTryStart, bool allowSelfHosted)
+{
+ MOZ_ASSERT(allowSelfHosted || emitterMode != BytecodeEmitter::SelfHosting,
+ ".close() on iterators is prohibited in self-hosted code because it "
+ "can run user-modifiable iteration code");
+
+ // Generate inline logic corresponding to IteratorClose (ES 7.4.6).
+ //
+ // Callers need to ensure that the iterator object is at the top of the
+ // stack.
+
+ if (!emit1(JSOP_DUP)) // ... ITER ITER
+ return false;
+
+ // Step 3.
+ //
+ // Get the "return" method.
+ if (!emitAtomOp(cx->names().return_, JSOP_CALLPROP)) // ... ITER RET
+ return false;
+
+ // Step 4.
+ //
+ // Do nothing if "return" is null or undefined.
+ IfThenElseEmitter ifReturnMethodIsDefined(this);
+ if (!emit1(JSOP_DUP)) // ... ITER RET RET
+ return false;
+ if (!emit1(JSOP_UNDEFINED)) // ... ITER RET RET UNDEFINED
+ return false;
+ if (!emit1(JSOP_NE)) // ... ITER RET ?NEQL
+ return false;
+ if (!ifReturnMethodIsDefined.emitIfElse())
+ return false;
+
+ // Steps 5, 8.
+ //
+ // Call "return" if it is not undefined or null, and check that it returns
+ // an Object.
+ if (!emit1(JSOP_SWAP)) // ... RET ITER
+ return false;
+
+ // ES 14.4.13, yield * AssignmentExpression, step 5.c
+ //
+ // When emitting iterator.return() for yield* forced return, we need to
+ // pass the argument passed to Generator.prototype.return to the return
+ // method.
+ if (yieldStarTryStart) {
+ IfThenElseEmitter ifGeneratorClosing(this);
+ if (!emitDupAt(2)) // ... FTYPE FVALUE RET ITER FVALUE
+ return false;
+ if (!emit1(JSOP_ISGENCLOSING)) // ... FTYPE FVALUE RET ITER FVALUE CLOSING
+ return false;
+ if (!emit1(JSOP_SWAP)) // ... FTYPE FVALUE RET ITER CLOSING FVALUE
+ return false;
+ if (!emit1(JSOP_POP)) // ... FTYPE FVALUE RET ITER CLOSING
+ return false;
+ if (!ifGeneratorClosing.emitIfElse()) // ... FTYPE FVALUE RET ITER
+ return false;
+
+ if (!emit1(JSOP_GETRVAL)) // ... FTYPE FVALUE RET ITER RVAL
+ return false;
+ if (!emitAtomOp(cx->names().value, JSOP_GETPROP)) // ... FTYPE FVALUE RET ITER VALUE
+ return false;
+ if (!emitCall(JSOP_CALL, 1)) // ... FTYPE FVALUE RESULT
+ return false;
+ checkTypeSet(JSOP_CALL);
+ if (!emitCheckIsObj(CheckIsObjectKind::IteratorReturn)) // ... FTYPE FVALUE RESULT
+ return false;
+
+ IfThenElseEmitter ifReturnDone(this);
+ if (!emit1(JSOP_DUP)) // ITER OLDRESULT FTYPE FVALUE RESULT RESULT
+ return false;
+ if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER OLDRESULT FTYPE FVALUE RESULT DONE
+ return false;
+ if (!ifReturnDone.emitIfElse()) // ITER OLDRESULT FTYPE FVALUE RESULT
+ return false;
+ if (!emit1(JSOP_DUP)) // ITER OLDRESULT FTYPE FVALUE RESULT RESULT
+ return false;
+ if (!emit1(JSOP_SETRVAL)) // ITER OLDRESULT FTYPE FVALUE RESULT
+ return false;
+ if (!ifReturnDone.emitElse()) // ITER OLDRESULT FTYPE FVALUE RESULT
+ return false;
+ int32_t savedDepth = this->stackDepth;
+ if (!emit2(JSOP_UNPICK, 3)) // ITER RESULT OLDRESULT FTYPE FVALUE
+ return false;
+ if (!emitUint16Operand(JSOP_POPN, 3)) // ITER RESULT
+ return false;
+ JumpList beq;
+ JumpTarget breakTarget{ -1 };
+ if (!emitBackwardJump(JSOP_GOTO, *yieldStarTryStart, &beq, &breakTarget)) // ITER RESULT
+ return false;
+ this->stackDepth = savedDepth;
+ if (!ifReturnDone.emitEnd())
+ return false;
+
+ if (!ifGeneratorClosing.emitElse()) // ... FTYPE FVALUE RET ITER
+ return false;
+ if (!emitCall(JSOP_CALL, 0)) // ... FTYPE FVALUE RESULT
+ return false;
+ checkTypeSet(JSOP_CALL);
+ if (!emitCheckIsObj(CheckIsObjectKind::IteratorReturn)) // ... FTYPE FVALUE RESULT
+ return false;
+
+ if (!ifGeneratorClosing.emitEnd())
+ return false;
+ } else {
+ if (!emitCall(JSOP_CALL, 0)) // ... RESULT
+ return false;
+ checkTypeSet(JSOP_CALL);
+ if (!emitCheckIsObj(CheckIsObjectKind::IteratorReturn)) // ... RESULT
+ return false;
+ }
+
+ if (!ifReturnMethodIsDefined.emitElse())
+ return false;
+ if (!emit1(JSOP_POP)) // ... ITER
+ return false;
+ if (!ifReturnMethodIsDefined.emitEnd())
+ return false;
+
+ return emit1(JSOP_POP); // ...
+}
+
+template <typename InnerEmitter>
+bool
+BytecodeEmitter::wrapWithIteratorCloseTryNote(int32_t iterDepth, InnerEmitter emitter)
+{
+ MOZ_ASSERT(this->stackDepth >= iterDepth);
+
+ ptrdiff_t start = offset();
+ if (!emitter(this))
+ return false;
+ ptrdiff_t end = offset();
+ if (start != end)
+ return tryNoteList.append(JSTRY_ITERCLOSE, iterDepth, start, end);
+ return true;
+}
+
+bool
BytecodeEmitter::emitDefault(ParseNode* defaultExpr, ParseNode* pattern)
{
if (!emit1(JSOP_DUP)) // VALUE VALUE
@@ -4617,156 +5048,6 @@ BytecodeEmitter::emitInitializerInBranch(ParseNode* initializer, ParseNode* patt
return emitInitializer(initializer, pattern);
}
-class MOZ_STACK_CLASS IfThenElseEmitter
-{
- BytecodeEmitter* bce_;
- JumpList jumpAroundThen_;
- JumpList jumpsAroundElse_;
- unsigned noteIndex_;
- int32_t thenDepth_;
-#ifdef DEBUG
- int32_t pushed_;
- bool calculatedPushed_;
-#endif
- enum State {
- Start,
- If,
- Cond,
- IfElse,
- Else,
- End
- };
- State state_;
-
- public:
- explicit IfThenElseEmitter(BytecodeEmitter* bce)
- : bce_(bce),
- noteIndex_(-1),
- thenDepth_(0),
-#ifdef DEBUG
- pushed_(0),
- calculatedPushed_(false),
-#endif
- state_(Start)
- {}
-
- ~IfThenElseEmitter()
- {}
-
- private:
- bool emitIf(State nextState) {
- MOZ_ASSERT(state_ == Start || state_ == Else);
- MOZ_ASSERT(nextState == If || nextState == IfElse || nextState == Cond);
-
- // Clear jumpAroundThen_ offset that points previous JSOP_IFEQ.
- if (state_ == Else)
- jumpAroundThen_ = JumpList();
-
- // Emit an annotated branch-if-false around the then part.
- SrcNoteType type = nextState == If ? SRC_IF : nextState == IfElse ? SRC_IF_ELSE : SRC_COND;
- if (!bce_->newSrcNote(type, &noteIndex_))
- return false;
- if (!bce_->emitJump(JSOP_IFEQ, &jumpAroundThen_))
- return false;
-
- // To restore stack depth in else part, save depth of the then part.
-#ifdef DEBUG
- // If DEBUG, this is also necessary to calculate |pushed_|.
- thenDepth_ = bce_->stackDepth;
-#else
- if (nextState == IfElse || nextState == Cond)
- thenDepth_ = bce_->stackDepth;
-#endif
- state_ = nextState;
- return true;
- }
-
- public:
- bool emitIf() {
- return emitIf(If);
- }
-
- bool emitCond() {
- return emitIf(Cond);
- }
-
- bool emitIfElse() {
- return emitIf(IfElse);
- }
-
- bool emitElse() {
- MOZ_ASSERT(state_ == IfElse || state_ == Cond);
-
- calculateOrCheckPushed();
-
- // Emit a jump from the end of our then part around the else part. The
- // patchJumpsToTarget call at the bottom of this function will fix up
- // the offset with jumpsAroundElse value.
- if (!bce_->emitJump(JSOP_GOTO, &jumpsAroundElse_))
- return false;
-
- // Ensure the branch-if-false comes here, then emit the else.
- if (!bce_->emitJumpTargetAndPatch(jumpAroundThen_))
- return false;
-
- // Annotate SRC_IF_ELSE or SRC_COND with the offset from branch to
- // jump, for IonMonkey's benefit. We can't just "back up" from the pc
- // of the else clause, because we don't know whether an extended
- // jump was required to leap from the end of the then clause over
- // the else clause.
- if (!bce_->setSrcNoteOffset(noteIndex_, 0,
- jumpsAroundElse_.offset - jumpAroundThen_.offset))
- {
- return false;
- }
-
- // Restore stack depth of the then part.
- bce_->stackDepth = thenDepth_;
- state_ = Else;
- return true;
- }
-
- bool emitEnd() {
- MOZ_ASSERT(state_ == If || state_ == Else);
-
- calculateOrCheckPushed();
-
- if (state_ == If) {
- // No else part, fixup the branch-if-false to come here.
- if (!bce_->emitJumpTargetAndPatch(jumpAroundThen_))
- return false;
- }
-
- // Patch all the jumps around else parts.
- if (!bce_->emitJumpTargetAndPatch(jumpsAroundElse_))
- return false;
-
- state_ = End;
- return true;
- }
-
- void calculateOrCheckPushed() {
-#ifdef DEBUG
- if (!calculatedPushed_) {
- pushed_ = bce_->stackDepth - thenDepth_;
- calculatedPushed_ = true;
- } else {
- MOZ_ASSERT(pushed_ == bce_->stackDepth - thenDepth_);
- }
-#endif
- }
-
-#ifdef DEBUG
- int32_t pushed() const {
- return pushed_;
- }
-
- int32_t popped() const {
- return -pushed_;
- }
-#endif
-};
-
bool
BytecodeEmitter::emitDestructuringOpsArray(ParseNode* pattern, DestructuringFlavor flav)
{
@@ -5710,7 +5991,7 @@ BytecodeEmitter::emitCatch(ParseNode* pn)
return false;
{
- NonLocalExitControl nle(this);
+ NonLocalExitControl nle(this, NonLocalExitControl::Throw);
// Move exception back to cx->exception to prepare for
// the next catch.
@@ -6303,12 +6584,14 @@ BytecodeEmitter::emitForOf(ParseNode* forOfLoop, EmitterScope* headLexicalEmitte
if (!emitIterator()) // ITER
return false;
+ int32_t iterDepth = stackDepth;
+
// For-of loops have both the iterator and the value on the stack. Push
// undefined to balance the stack.
if (!emit1(JSOP_UNDEFINED)) // ITER RESULT
return false;
- LoopControl loopInfo(this, StatementKind::ForOfLoop);
+ ForOfLoopControl loopInfo(this, iterDepth);
// Annotate so IonMonkey can find the loop-closing jump.
unsigned noteIndex;
@@ -6354,18 +6637,23 @@ BytecodeEmitter::emitForOf(ParseNode* forOfLoop, EmitterScope* headLexicalEmitte
#endif
// Emit code to assign result.value to the iteration variable.
+ //
+ // Note that ES 13.7.5.13, step 5.c says getting result.value does not
+ // call IteratorClose, so start JSTRY_ITERCLOSE after the GETPROP.
if (!emit1(JSOP_DUP)) // ITER RESULT RESULT
return false;
if (!emitAtomOp(cx->names().value, JSOP_GETPROP)) // ITER RESULT VALUE
return false;
+ loopInfo.startNewIterCloseTryNote(this);
+
if (!emitInitializeForInOrOfTarget(forOfHead)) // ITER RESULT VALUE
return false;
if (!emit1(JSOP_POP)) // ITER RESULT
return false;
- MOZ_ASSERT(this->stackDepth == loopDepth,
+ MOZ_ASSERT(stackDepth == loopDepth,
"the stack must be balanced around the initializing "
"operation");
@@ -6374,6 +6662,9 @@ BytecodeEmitter::emitForOf(ParseNode* forOfLoop, EmitterScope* headLexicalEmitte
if (!emitTree(forBody)) // ITER RESULT
return false;
+ if (!loopInfo.finishIterCloseTryNote(this))
+ return false;
+
// Set offset for continues.
loopInfo.continueTarget = { offset() };
@@ -7609,7 +7900,7 @@ BytecodeEmitter::emitReturn(ParseNode* pn)
return false;
}
- NonLocalExitControl nle(this);
+ NonLocalExitControl nle(this, NonLocalExitControl::Return);
if (!nle.prepareForNonLocalJumpToOutermost())
return false;
diff --git a/js/src/frontend/BytecodeEmitter.h b/js/src/frontend/BytecodeEmitter.h
index 066c06672..6b39069de 100644
--- a/js/src/frontend/BytecodeEmitter.h
+++ b/js/src/frontend/BytecodeEmitter.h
@@ -679,6 +679,12 @@ struct MOZ_STACK_CLASS BytecodeEmitter
// Pops iterator from the top of the stack. Pushes the result of |.next()|
// onto the stack.
MOZ_MUST_USE bool emitIteratorNext(ParseNode* pn, bool allowSelfHosted = false);
+ MOZ_MUST_USE bool emitIteratorClose(
+ mozilla::Maybe<JumpTarget> yieldStarTryStart = mozilla::Nothing(),
+ bool allowSelfHosted = false);
+
+ template <typename InnerEmitter>
+ MOZ_MUST_USE bool wrapWithIteratorCloseTryNote(int32_t iterDepth, InnerEmitter emitter);
// Check if the value on top of the stack is "undefined". If so, replace
// that value on the stack with the value defined by |defaultExpr|.
diff --git a/js/src/jit/JitFrames.cpp b/js/src/jit/JitFrames.cpp
index 646442b4c..d6c6fc4c9 100644
--- a/js/src/jit/JitFrames.cpp
+++ b/js/src/jit/JitFrames.cpp
@@ -328,11 +328,15 @@ NumArgAndLocalSlots(const InlineFrameIterator& frame)
}
static void
-CloseLiveIteratorIon(JSContext* cx, const InlineFrameIterator& frame, uint32_t stackSlot)
+CloseLiveIteratorIon(JSContext* cx, const InlineFrameIterator& frame, JSTryNote* tn)
{
+ MOZ_ASSERT(tn->kind == JSTRY_FOR_IN || tn->kind == JSTRY_ITERCLOSE);
+ MOZ_ASSERT(tn->stackDepth > 0);
+
SnapshotIterator si = frame.snapshotIterator();
// Skip stack slots until we reach the iterator object.
+ uint32_t stackSlot = tn->stackDepth;
uint32_t skipSlots = NumArgAndLocalSlots(frame) + stackSlot - 1;
for (unsigned i = 0; i < skipSlots; i++)
@@ -341,10 +345,14 @@ CloseLiveIteratorIon(JSContext* cx, const InlineFrameIterator& frame, uint32_t s
Value v = si.read();
RootedObject obj(cx, &v.toObject());
- if (cx->isExceptionPending())
- UnwindIteratorForException(cx, obj);
- else
+ if (cx->isExceptionPending()) {
+ if (tn->kind == JSTRY_FOR_IN)
+ UnwindIteratorForException(cx, obj);
+ else
+ IteratorCloseForException(cx, obj);
+ } else {
UnwindIteratorForUncatchableException(cx, obj);
+ }
}
class IonFrameStackDepthOp
@@ -417,12 +425,13 @@ HandleExceptionIon(JSContext* cx, const InlineFrameIterator& frame, ResumeFromEx
JSTryNote* tn = *tni;
switch (tn->kind) {
- case JSTRY_FOR_IN: {
- MOZ_ASSERT(JSOp(*(script->main() + tn->start + tn->length)) == JSOP_ENDITER);
+ case JSTRY_FOR_IN:
+ case JSTRY_ITERCLOSE: {
+ MOZ_ASSERT_IF(tn->kind == JSTRY_FOR_IN,
+ JSOp(*(script->main() + tn->start + tn->length)) == JSOP_ENDITER);
MOZ_ASSERT(tn->stackDepth > 0);
- uint32_t localSlot = tn->stackDepth;
- CloseLiveIteratorIon(cx, frame, localSlot);
+ CloseLiveIteratorIon(cx, frame, tn);
break;
}
@@ -598,17 +607,23 @@ ProcessTryNotesBaseline(JSContext* cx, const JitFrameIterator& frame, Environmen
return true;
}
- case JSTRY_FOR_IN: {
+ case JSTRY_FOR_IN:
+ case JSTRY_ITERCLOSE: {
uint8_t* framePointer;
uint8_t* stackPointer;
BaselineFrameAndStackPointersFromTryNote(tn, frame, &framePointer, &stackPointer);
- Value iterValue(*(Value*) stackPointer);
+ Value iterValue(*(reinterpret_cast<Value*>(stackPointer)));
RootedObject iterObject(cx, &iterValue.toObject());
- if (!UnwindIteratorForException(cx, iterObject)) {
+ bool ok;
+ if (tn->kind == JSTRY_FOR_IN)
+ ok = UnwindIteratorForException(cx, iterObject);
+ else
+ ok = IteratorCloseForException(cx, iterObject);
+ if (!ok) {
// See comment in the JSTRY_FOR_IN case in Interpreter.cpp's
// ProcessTryNotes.
SettleOnTryNote(cx, tn, frame, ei, rfe, pc);
- MOZ_ASSERT(**pc == JSOP_ENDITER);
+ MOZ_ASSERT_IF(tn->kind == JSTRY_FOR_IN, **pc == JSOP_ENDITER);
return false;
}
break;
diff --git a/js/src/js.msg b/js/src/js.msg
index 8766bfbf5..30c0d3035 100644
--- a/js/src/js.msg
+++ b/js/src/js.msg
@@ -96,7 +96,7 @@ MSG_DEF(JSMSG_NOT_ITERABLE, 1, JSEXN_TYPEERR, "{0} is not iterable")
MSG_DEF(JSMSG_NOT_ITERATOR, 1, JSEXN_TYPEERR, "{0} is not iterator")
MSG_DEF(JSMSG_ALREADY_HAS_PRAGMA, 2, JSEXN_WARN, "{0} is being assigned a {1}, but already has one")
MSG_DEF(JSMSG_GET_ITER_RETURNED_PRIMITIVE, 0, JSEXN_TYPEERR, "[Symbol.iterator]() returned a non-object value")
-MSG_DEF(JSMSG_NEXT_RETURNED_PRIMITIVE, 0, JSEXN_TYPEERR, "iterator.next() returned a non-object value")
+MSG_DEF(JSMSG_ITER_METHOD_RETURNED_PRIMITIVE, 1, JSEXN_TYPEERR, "iterator.{0}() returned a non-object value")
MSG_DEF(JSMSG_CANT_SET_PROTO, 0, JSEXN_TYPEERR, "can't set prototype of this object")
MSG_DEF(JSMSG_CANT_SET_PROTO_OF, 1, JSEXN_TYPEERR, "can't set prototype of {0}")
MSG_DEF(JSMSG_CANT_SET_PROTO_CYCLE, 0, JSEXN_TYPEERR, "can't set prototype: it would cause a prototype chain cycle")
diff --git a/js/src/jsiter.cpp b/js/src/jsiter.cpp
index 63c81e6af..c1ae5dc15 100644
--- a/js/src/jsiter.cpp
+++ b/js/src/jsiter.cpp
@@ -12,6 +12,7 @@
#include "mozilla/Maybe.h"
#include "mozilla/MemoryReporting.h"
#include "mozilla/PodOperations.h"
+#include "mozilla/Unused.h"
#include "jsarray.h"
#include "jsatom.h"
@@ -1229,6 +1230,7 @@ js::CloseIterator(JSContext* cx, HandleObject obj)
}
return LegacyGeneratorObject::close(cx, obj);
}
+
return true;
}
@@ -1246,6 +1248,56 @@ js::UnwindIteratorForException(JSContext* cx, HandleObject obj)
return true;
}
+bool
+js::IteratorCloseForException(JSContext* cx, HandleObject obj)
+{
+ MOZ_ASSERT(cx->isExceptionPending());
+
+ bool isClosingGenerator = cx->isClosingGenerator();
+ JS::AutoSaveExceptionState savedExc(cx);
+
+ // Implements IteratorClose (ES 7.4.6) for exception unwinding. See
+ // also the bytecode generated by BytecodeEmitter::emitIteratorClose.
+
+ // Step 3.
+ //
+ // Get the "return" method.
+ RootedValue returnMethod(cx);
+ if (!GetProperty(cx, obj, obj, cx->names().return_, &returnMethod))
+ return false;
+
+ // Step 4.
+ //
+ // Do nothing if "return" is null or undefined. Throw a TypeError if the
+ // method is not IsCallable.
+ if (returnMethod.isNullOrUndefined())
+ return true;
+ if (!IsCallable(returnMethod))
+ return ReportIsNotFunction(cx, returnMethod);
+
+ // Step 5, 6, 8.
+ //
+ // Call "return" if it is not null or undefined.
+ RootedValue rval(cx);
+ bool ok = Call(cx, returnMethod, obj, &rval);
+ if (isClosingGenerator) {
+ // Closing an iterator is implemented as an exception, but in spec
+ // terms it is a Completion value with [[Type]] return. In this case
+ // we *do* care if the call threw and if it returned an object.
+ if (!ok)
+ return false;
+ if (!rval.isObject())
+ return ThrowCheckIsObject(cx, CheckIsObjectKind::IteratorReturn);
+ } else {
+ // We don't care if the call threw or that it returned an Object, as
+ // Step 6 says if IteratorClose is being called during a throw, the
+ // original throw has primacy.
+ savedExc.restore();
+ }
+
+ return true;
+}
+
void
js::UnwindIteratorForUncatchableException(JSContext* cx, JSObject* obj)
{
diff --git a/js/src/jsiter.h b/js/src/jsiter.h
index 35d7ef118..f11f09b55 100644
--- a/js/src/jsiter.h
+++ b/js/src/jsiter.h
@@ -189,6 +189,9 @@ CloseIterator(JSContext* cx, HandleObject iterObj);
bool
UnwindIteratorForException(JSContext* cx, HandleObject obj);
+bool
+IteratorCloseForException(JSContext* cx, HandleObject obj);
+
void
UnwindIteratorForUncatchableException(JSContext* cx, JSObject* obj);
diff --git a/js/src/jsscript.h b/js/src/jsscript.h
index 690bc225d..b48d48686 100644
--- a/js/src/jsscript.h
+++ b/js/src/jsscript.h
@@ -84,7 +84,8 @@ enum JSTryNoteKind {
JSTRY_FINALLY,
JSTRY_FOR_IN,
JSTRY_FOR_OF,
- JSTRY_LOOP
+ JSTRY_LOOP,
+ JSTRY_ITERCLOSE
};
/*
diff --git a/js/src/shell/js.cpp b/js/src/shell/js.cpp
index 3f56981cd..294dd935d 100644
--- a/js/src/shell/js.cpp
+++ b/js/src/shell/js.cpp
@@ -2589,7 +2589,8 @@ JS_STATIC_ASSERT(JSTRY_CATCH == 0);
JS_STATIC_ASSERT(JSTRY_FINALLY == 1);
JS_STATIC_ASSERT(JSTRY_FOR_IN == 2);
-static const char* const TryNoteNames[] = { "catch", "finally", "for-in", "for-of", "loop" };
+static const char* const TryNoteNames[] = { "catch", "finally", "for-in", "for-of", "loop",
+ "iterclose" };
static MOZ_MUST_USE bool
TryNotes(JSContext* cx, HandleScript script, Sprinter* sp)
@@ -2597,15 +2598,15 @@ TryNotes(JSContext* cx, HandleScript script, Sprinter* sp)
if (!script->hasTrynotes())
return true;
- if (sp->put("\nException table:\nkind stack start end\n") < 0)
+ if (sp->put("\nException table:\nkind stack start end\n") < 0)
return false;
JSTryNote* tn = script->trynotes()->vector;
JSTryNote* tnlimit = tn + script->trynotes()->length;
do {
MOZ_ASSERT(tn->kind < ArrayLength(TryNoteNames));
- uint8_t startOff = script->pcToOffset(script->main()) + tn->start;
- if (!sp->jsprintf(" %-7s %6u %8u %8u\n",
+ uint32_t startOff = script->pcToOffset(script->main()) + tn->start;
+ if (!sp->jsprintf(" %-9s %6u %8u %8u\n",
TryNoteNames[tn->kind], tn->stackDepth,
startOff, startOff + tn->length))
{
diff --git a/js/src/tests/ecma_6/Statements/for-of-iterator-close.js b/js/src/tests/ecma_6/Statements/for-of-iterator-close.js
new file mode 100644
index 000000000..b28895d8f
--- /dev/null
+++ b/js/src/tests/ecma_6/Statements/for-of-iterator-close.js
@@ -0,0 +1,102 @@
+// Tests that IteratorReturn is called when a for-of loop has an abrupt
+// completion value during non-iterator code.
+
+function test() {
+ var returnCalled = 0;
+ var returnCalledExpected = 0;
+ var iterable = {};
+ iterable[Symbol.iterator] = makeIterator({
+ ret: function() {
+ returnCalled++;
+ return {};
+ }
+ });
+
+ // break calls iter.return
+ for (var x of iterable)
+ break;
+ assertEq(returnCalled, ++returnCalledExpected);
+
+ // throw in body calls iter.return
+ assertThrowsValue(function() {
+ for (var x of iterable)
+ throw "in body";
+ }, "in body");
+ assertEq(returnCalled, ++returnCalledExpected);
+
+ // throw in lhs ref calls iter.return
+ function throwlhs() {
+ throw "in lhs";
+ }
+ assertThrowsValue(function() {
+ for ((throwlhs()) of iterable)
+ continue;
+ }, "in lhs");
+ assertEq(returnCalled, ++returnCalledExpected);
+
+ // throw in iter.return doesn't re-call iter.return
+ iterable[Symbol.iterator] = makeIterator({
+ ret: function() {
+ returnCalled++;
+ throw "in iter.return";
+ }
+ });
+ assertThrowsValue(function() {
+ for (var x of iterable)
+ break;
+ }, "in iter.return");
+ assertEq(returnCalled, ++returnCalledExpected);
+
+ // throw in iter.next doesn't call IteratorClose
+ iterable[Symbol.iterator] = makeIterator({
+ next: function() {
+ throw "in next";
+ }
+ });
+ assertThrowsValue(function() {
+ for (var x of iterable)
+ break;
+ }, "in next");
+ assertEq(returnCalled, returnCalledExpected);
+
+ // "return" must return an Object.
+ iterable[Symbol.iterator] = makeIterator({
+ ret: function() {
+ returnCalled++;
+ return 42;
+ }
+ });
+ assertThrowsInstanceOf(function() {
+ for (var x of iterable)
+ break;
+ }, TypeError);
+ assertEq(returnCalled, ++returnCalledExpected);
+
+ // continue doesn't call iter.return for the loop it's continuing
+ var i = 0;
+ iterable[Symbol.iterator] = makeIterator({
+ next: function() {
+ return { done: i++ > 5 };
+ },
+ ret: function() {
+ returnCalled++;
+ return {};
+ }
+ });
+ for (var x of iterable)
+ continue;
+ assertEq(returnCalled, returnCalledExpected);
+
+ // continue does call iter.return for loops it skips
+ i = 0;
+ L: do {
+ for (var x of iterable)
+ continue L;
+ } while (false);
+ assertEq(returnCalled, ++returnCalledExpected);
+}
+
+test();
+
+if (typeof reportCompare === "function")
+ reportCompare(0, 0);
diff --git a/js/src/tests/ecma_6/shell.js b/js/src/tests/ecma_6/shell.js
index 06be6f2db..1d067a282 100644
--- a/js/src/tests/ecma_6/shell.js
+++ b/js/src/tests/ecma_6/shell.js
@@ -3,21 +3,39 @@
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
(function(global) {
- /** Yield every permutation of the elements in some array. */
- global.Permutations = function* Permutations(items) {
- if (items.length == 0) {
- yield [];
- } else {
- items = items.slice(0);
- for (let i = 0; i < items.length; i++) {
- let swap = items[0];
- items[0] = items[i];
- items[i] = swap;
- for (let e of Permutations(items.slice(1, items.length)))
- yield [items[0]].concat(e);
- }
- }
- };
+ /** Yield every permutation of the elements in some array. */
+ global.Permutations = function* Permutations(items) {
+ if (items.length == 0) {
+ yield [];
+ } else {
+ items = items.slice(0);
+ for (let i = 0; i < items.length; i++) {
+ let swap = items[0];
+ items[0] = items[i];
+ items[i] = swap;
+ for (let e of Permutations(items.slice(1, items.length)))
+ yield [items[0]].concat(e);
+ }
+ }
+ };
+
+ /** Make an iterator with a return method. */
+ global.makeIterator = function makeIterator(overrides) {
+ var iterator = {
+ next: function() {
+ if (overrides && overrides.next)
+ return overrides.next();
+ return { done: false };
+ },
+ return: function() {
+ if (overrides && overrides.ret)
+ return overrides.ret();
+ return { done: true };
+ }
+ };
+
+ return function() { return iterator; };
+ };
})(this);
if (typeof assertThrowsInstanceOf === 'undefined') {
diff --git a/js/src/vm/Interpreter.cpp b/js/src/vm/Interpreter.cpp
index 8ae9c43b0..489d0a155 100644
--- a/js/src/vm/Interpreter.cpp
+++ b/js/src/vm/Interpreter.cpp
@@ -1171,13 +1171,19 @@ ProcessTryNotes(JSContext* cx, EnvironmentIter& ei, InterpreterRegs& regs)
SettleOnTryNote(cx, tn, ei, regs);
return FinallyContinuation;
- case JSTRY_FOR_IN: {
+ case JSTRY_FOR_IN:
+ case JSTRY_ITERCLOSE: {
/* This is similar to JSOP_ENDITER in the interpreter loop. */
DebugOnly<jsbytecode*> pc = regs.fp()->script()->main() + tn->start + tn->length;
- MOZ_ASSERT(JSOp(*pc) == JSOP_ENDITER);
+ MOZ_ASSERT_IF(tn->kind == JSTRY_FOR_IN, JSOp(*pc) == JSOP_ENDITER);
Value* sp = regs.spForStackDepth(tn->stackDepth);
RootedObject obj(cx, &sp[-1].toObject());
- if (!UnwindIteratorForException(cx, obj)) {
+ bool ok;
+ if (tn->kind == JSTRY_FOR_IN)
+ ok = UnwindIteratorForException(cx, obj);
+ else
+ ok = IteratorCloseForException(cx, obj);
+ if (!ok) {
// We should only settle on the note only if
// UnwindIteratorForException itself threw, as
// onExceptionUnwind should be called anew with the new
@@ -5040,7 +5046,12 @@ js::ThrowCheckIsObject(JSContext* cx, CheckIsObjectKind kind)
{
switch (kind) {
case CheckIsObjectKind::IteratorNext:
- JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_NEXT_RETURNED_PRIMITIVE);
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_ITER_METHOD_RETURNED_PRIMITIVE, "next");
+ break;
+ case CheckIsObjectKind::IteratorReturn:
+ JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr,
+ JSMSG_ITER_METHOD_RETURNED_PRIMITIVE, "return");
break;
case CheckIsObjectKind::GetIterator:
JS_ReportErrorNumberASCII(cx, GetErrorMessage, nullptr, JSMSG_GET_ITER_RETURNED_PRIMITIVE);
diff --git a/js/src/vm/Interpreter.h b/js/src/vm/Interpreter.h
index 1ffe1fdca..3a24240fc 100644
--- a/js/src/vm/Interpreter.h
+++ b/js/src/vm/Interpreter.h
@@ -562,6 +562,7 @@ ReportRuntimeRedeclaration(JSContext* cx, HandlePropertyName name, const char* r
enum class CheckIsObjectKind : uint8_t {
IteratorNext,
+ IteratorReturn,
GetIterator
};
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-10 14:39:58 +0000