diff options
Diffstat (limited to 'js/src/frontend/BytecodeEmitter.cpp')
| -rw-r--r-- | js/src/frontend/BytecodeEmitter.cpp | 257 |
1 files changed, 119 insertions, 138 deletions
diff --git a/js/src/frontend/BytecodeEmitter.cpp b/js/src/frontend/BytecodeEmitter.cpp index ee26d0c43..a68fe8538 100644 --- a/js/src/frontend/BytecodeEmitter.cpp +++ b/js/src/frontend/BytecodeEmitter.cpp @@ -4463,13 +4463,6 @@ BytecodeEmitter::emitDestructuringLHS(ParseNode* target, DestructuringFlavor fla } bool -BytecodeEmitter::emitDestructuringLHSInBranch(ParseNode* target, DestructuringFlavor flav) -{ - TDZCheckCache tdzCache(this); - return emitDestructuringLHS(target, flav); -} - -bool BytecodeEmitter::emitIteratorNext(ParseNode* pn, bool allowSelfHosted) { MOZ_ASSERT(allowSelfHosted || emitterMode != BytecodeEmitter::SelfHosting, @@ -4739,7 +4732,7 @@ BytecodeEmitter::emitDestructuringOpsArray(ParseNode* pattern, DestructuringFlav // // let x, y; // let a, b, c, d; - // let tmp, done, iter, result; // stack values + // let iter, result, done, value; // stack values // // iter = x[Symbol.iterator](); // @@ -4747,115 +4740,113 @@ BytecodeEmitter::emitDestructuringOpsArray(ParseNode* pattern, DestructuringFlav // result = iter.next(); // done = result.done; // - // if (done) { - // a = undefined; - // - // result = undefined; - // done = true; - // } else { - // a = result.value; + // if (done) + // value = undefined; + // else + // value = result.value; // - // // Do next element's .next() and .done access here - // result = iter.next(); - // done = result.done; - // } + // a = value; // // // ==== emitted by loop for b ==== // if (done) { - // b = undefined; - // - // result = undefined; - // done = true; + // value = undefined; // } else { - // b = result.value; - // // result = iter.next(); // done = result.done; + // if (done) + // value = undefined; + // else + // value = result.value; // } // + // b = value; + // // // ==== emitted by loop for elision ==== // if (done) { - // result = undefined - // done = true + // value = undefined; // } else { - // result.value; - // // result = iter.next(); // done = result.done; + // if (done) + // value = undefined; + // else + // value = result.value; // } // // // ==== emitted by loop for c ==== // if (done) { - // c = y; + // value = undefined; // } else { - // tmp = result.value; - // if (tmp === undefined) - // tmp = y; - // c = tmp; - // - // // Don't do next element's .next() and .done access if - // // this is the last non-spread element. + // result = iter.next(); + // done = result.done; + // if (done) + // value = undefined; + // else + // value = result.value; // } // + // if (value === undefined) + // value = y; + // + // c = value; + // // // ==== emitted by loop for d ==== - // if (done) { - // // Assing empty array when completed - // d = []; - // } else { - // d = [...iter]; - // } + // if (done) + // value = []; + // else + // value = [...iter]; + // + // d = value; - /* - * Use an iterator to destructure the RHS, instead of index lookup. We - * must leave the *original* value on the stack. - */ + // Use an iterator to destructure the RHS, instead of index lookup. We + // must leave the *original* value on the stack. if (!emit1(JSOP_DUP)) // ... OBJ OBJ return false; - if (!emitIterator()) // ... OBJ? ITER + if (!emitIterator()) // ... OBJ ITER return false; - bool needToPopIterator = true; for (ParseNode* member = pattern->pn_head; member; member = member->pn_next) { bool isHead = member == pattern->pn_head; + bool hasNext = !!member->pn_next; + if (member->isKind(PNK_SPREAD)) { IfThenElseEmitter ifThenElse(this); if (!isHead) { // If spread is not the first element of the pattern, // iterator can already be completed. - if (!ifThenElse.emitIfElse()) // ... OBJ? ITER + // ... OBJ ITER DONE + if (!ifThenElse.emitIfElse()) // ... OBJ ITER return false; - if (!emit1(JSOP_POP)) // ... OBJ? - return false; - if (!emitUint32Operand(JSOP_NEWARRAY, 0)) // ... OBJ? ARRAY + if (!emitUint32Operand(JSOP_NEWARRAY, 0)) // ... OBJ ITER ARRAY return false; - if (!emitDestructuringLHSInBranch(member, flav)) // ... OBJ? - return false; - - if (!ifThenElse.emitElse()) // ... OBJ? ITER + if (!ifThenElse.emitElse()) // ... OBJ ITER return false; } // If iterator is not completed, create a new array with the rest // of the iterator. - if (!emitUint32Operand(JSOP_NEWARRAY, 0)) // ... OBJ? ITER ARRAY + if (!emit1(JSOP_DUP)) // ... OBJ ITER return false; - if (!emitNumberOp(0)) // ... OBJ? ITER ARRAY INDEX + if (!emitUint32Operand(JSOP_NEWARRAY, 0)) // ... OBJ ITER ITER ARRAY return false; - if (!emitSpread()) // ... OBJ? ARRAY INDEX + if (!emitNumberOp(0)) // ... OBJ ITER ITER ARRAY INDEX return false; - if (!emit1(JSOP_POP)) // ... OBJ? ARRAY + if (!emitSpread()) // ... OBJ ITER ARRAY INDEX return false; - if (!emitDestructuringLHSInBranch(member, flav)) // ... OBJ? + if (!emit1(JSOP_POP)) // ... OBJ ITER ARRAY return false; if (!isHead) { if (!ifThenElse.emitEnd()) return false; - MOZ_ASSERT(ifThenElse.popped() == 1); + MOZ_ASSERT(ifThenElse.pushed() == 1); } - needToPopIterator = false; - MOZ_ASSERT(!member->pn_next); + + if (!emitDestructuringLHS(member, flav)) // ... OBJ ITER + return false; + + MOZ_ASSERT(!hasNext); break; } @@ -4867,110 +4858,100 @@ BytecodeEmitter::emitDestructuringOpsArray(ParseNode* pattern, DestructuringFlav } bool isElision = subpattern->isKind(PNK_ELISION); - bool hasNextNonSpread = member->pn_next && !member->pn_next->isKind(PNK_SPREAD); - bool hasNextSpread = member->pn_next && member->pn_next->isKind(PNK_SPREAD); MOZ_ASSERT(!subpattern->isKind(PNK_SPREAD)); - auto emitNext = [pattern](ExclusiveContext* cx, BytecodeEmitter* bce) { - if (!bce->emit1(JSOP_DUP)) // ... OBJ? ITER ITER - return false; - if (!bce->emitIteratorNext(pattern)) // ... OBJ? ITER RESULT + IfThenElseEmitter ifAlreadyDone(this); + if (!isHead) { + // If this element is not the first element of the pattern, + // iterator can already be completed. + // ... OBJ ITER DONE + if (hasNext) { + if (!emit1(JSOP_DUP)) // ... OBJ ITER DONE DONE + return false; + } + if (!ifAlreadyDone.emitIfElse()) // ... OBJ ITER ?DONE return false; - if (!bce->emit1(JSOP_DUP)) // ... OBJ? ITER RESULT RESULT + + if (!emit1(JSOP_UNDEFINED)) // ... OBJ ITER ?DONE UNDEF return false; - if (!bce->emitAtomOp(cx->names().done, JSOP_GETPROP)) // ... OBJ? ITER RESULT DONE? + if (!emit1(JSOP_NOP_DESTRUCTURING)) // ... OBJ ITER ?DONE UNDEF return false; - return true; - }; - if (isHead) { - if (!emitNext(cx, this)) // ... OBJ? ITER RESULT DONE? + if (!ifAlreadyDone.emitElse()) // ... OBJ ITER ?DONE return false; + + if (hasNext) { + if (!emit1(JSOP_POP)) // ... OBJ ITER + return false; + } } - IfThenElseEmitter ifThenElse(this); - if (!ifThenElse.emitIfElse()) // ... OBJ? ITER RESULT + if (!emit1(JSOP_DUP)) // ... OBJ ITER ITER return false; - - if (!emit1(JSOP_POP)) // ... OBJ? ITER + if (!emitIteratorNext(pattern)) // ... OBJ ITER RESULT return false; - if (pndefault) { - // Emit only pndefault tree here, as undefined check in emitDefault - // should always be true. - if (!emitInitializerInBranch(pndefault, subpattern)) // ... OBJ? ITER VALUE + if (!emit1(JSOP_DUP)) // ... OBJ ITER RESULT RESULT + return false; + if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ... OBJ ITER RESULT DONE + return false; + + if (hasNext) { + if (!emit1(JSOP_DUP)) // ... OBJ ITER RESULT DONE DONE return false; - } else { - if (!isElision) { - if (!emit1(JSOP_UNDEFINED)) // ... OBJ? ITER UNDEFINED - return false; - if (!emit1(JSOP_NOP_DESTRUCTURING)) - return false; - } } - if (!isElision) { - if (!emitDestructuringLHSInBranch(subpattern, flav)) // ... OBJ? ITER - return false; - } else if (pndefault) { - if (!emit1(JSOP_POP)) // ... OBJ? ITER + + IfThenElseEmitter ifDone(this); + if (!ifDone.emitIfElse()) // ... OBJ ITER RESULT ?DONE + return false; + + if (hasNext) { + if (!emit1(JSOP_SWAP)) // ... OBJ ITER ?DONE RESULT return false; } + if (!emit1(JSOP_POP)) // ... OBJ ITER ?DONE + return false; + if (!emit1(JSOP_UNDEFINED)) // ... OBJ ITER ?DONE UNDEF + return false; + if (!emit1(JSOP_NOP_DESTRUCTURING)) // ... OBJ ITER ?DONE UNDEF + return false; - // Setup next element's result when the iterator is done. - if (hasNextNonSpread) { - if (!emit1(JSOP_UNDEFINED)) // ... OBJ? ITER RESULT - return false; - if (!emit1(JSOP_NOP_DESTRUCTURING)) - return false; - if (!emit1(JSOP_TRUE)) // ... OBJ? ITER RESULT DONE? - return false; - } else if (hasNextSpread) { - if (!emit1(JSOP_TRUE)) // ... OBJ? ITER DONE? + if (!ifDone.emitElse()) // ... OBJ ITER RESULT ?DONE + return false; + + if (hasNext) { + if (!emit1(JSOP_SWAP)) // ... OBJ ITER ?DONE RESULT return false; } - - if (!ifThenElse.emitElse()) // ... OBJ? ITER RESULT + if (!emitAtomOp(cx->names().value, JSOP_GETPROP)) // ... OBJ ITER ?DONE VALUE return false; - if (!emitAtomOp(cx->names().value, JSOP_GETPROP)) // ... OBJ? ITER VALUE + if (!ifDone.emitEnd()) return false; + MOZ_ASSERT(ifDone.pushed() == 0); - if (pndefault) { - if (!emitDefault(pndefault, subpattern)) // ... OBJ? ITER VALUE + if (!isHead) { + if (!ifAlreadyDone.emitEnd()) return false; + MOZ_ASSERT(ifAlreadyDone.pushed() == 1); } - if (!isElision) { - if (!emitDestructuringLHSInBranch(subpattern, flav)) // ... OBJ? ITER - return false; - } else { - if (!emit1(JSOP_POP)) // ... OBJ? ITER + if (pndefault) { + if (!emitDefault(pndefault, subpattern)) // ... OBJ ITER ?DONE VALUE return false; } - // Setup next element's result when the iterator is not done. - if (hasNextNonSpread) { - if (!emitNext(cx, this)) // ... OBJ? ITER RESULT DONE? + if (!isElision) { + if (!emitDestructuringLHS(subpattern, flav)) // ... OBJ ITER ?DONE return false; - } else if (hasNextSpread) { - if (!emit1(JSOP_FALSE)) // ... OBJ? ITER DONE? + } else { + if (!emit1(JSOP_POP)) // ... OBJ ITER ?DONE return false; } - - if (!ifThenElse.emitEnd()) - return false; - if (hasNextNonSpread) - MOZ_ASSERT(ifThenElse.pushed() == 1); - else if (hasNextSpread) - MOZ_ASSERT(ifThenElse.pushed() == 0); - else - MOZ_ASSERT(ifThenElse.popped() == 1); } - if (needToPopIterator) { - if (!emit1(JSOP_POP)) // ... OBJ? - return false; - } + if (!emit1(JSOP_POP)) // ... OBJ + return false; return true; } @@ -6118,7 +6099,7 @@ BytecodeEmitter::emitSpread(bool allowSelfHosted) return false; if (!emit1(JSOP_DUP)) // ITER ARR I RESULT RESULT return false; - if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER ARR I RESULT DONE? + if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER ARR I RESULT DONE return false; if (!emitBackwardJump(JSOP_IFEQ, top, &beq, &breakTarget)) // ITER ARR I RESULT @@ -6307,7 +6288,7 @@ BytecodeEmitter::emitForOf(ParseNode* forOfLoop, EmitterScope* headLexicalEmitte return false; if (!emit1(JSOP_DUP)) // ITER RESULT RESULT return false; - if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER RESULT DONE? + if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER RESULT DONE return false; if (!emitBackwardJump(JSOP_IFEQ, top, &beq, &breakTarget)) @@ -6803,7 +6784,7 @@ BytecodeEmitter::emitComprehensionForOf(ParseNode* pn) return false; if (!emit1(JSOP_DUP)) // ITER RESULT RESULT return false; - if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER RESULT DONE? + if (!emitAtomOp(cx->names().done, JSOP_GETPROP)) // ITER RESULT DONE return false; JumpList beq; |