Adding upstream version 124.0.1.upstream/124.0.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 257 insertions, 0 deletions

diff --git a/js/src/frontend/ElemOpEmitter.cpp b/js/src/frontend/ElemOpEmitter.cpp
new file mode 100644
index 0000000000..0d563e466d
--- /dev/null
+++ b/js/src/frontend/ElemOpEmitter.cpp
@@ -0,0 +1,257 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=8 sts=2 et sw=2 tw=80:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "frontend/ElemOpEmitter.h"
+
+#include "frontend/BytecodeEmitter.h"
+#include "frontend/SharedContext.h"
+#include "vm/Opcodes.h"
+#include "vm/ThrowMsgKind.h"  // ThrowMsgKind
+
+using namespace js;
+using namespace js::frontend;
+
+ElemOpEmitter::ElemOpEmitter(BytecodeEmitter* bce, Kind kind, ObjKind objKind)
+    : bce_(bce), kind_(kind), objKind_(objKind) {}
+
+bool ElemOpEmitter::prepareForObj() {
+  MOZ_ASSERT(state_ == State::Start);
+
+#ifdef DEBUG
+  state_ = State::Obj;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::prepareForKey() {
+  MOZ_ASSERT(state_ == State::Obj);
+
+  if (isCall()) {
+    if (!bce_->emit1(JSOp::Dup)) {
+      //            [stack] # if Super
+      //            [stack] THIS THIS
+      //            [stack] # otherwise
+      //            [stack] OBJ OBJ
+      return false;
+    }
+  }
+
+#ifdef DEBUG
+  state_ = State::Key;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::emitGet() {
+  MOZ_ASSERT(state_ == State::Key);
+
+  // Inc/dec and compound assignment use the KEY twice, but if it's an object,
+  // it must be converted ToPropertyKey only once, per spec.
+  if (isIncDec() || isCompoundAssignment()) {
+    if (!bce_->emit1(JSOp::ToPropertyKey)) {
+      //            [stack] # if Super
+      //            [stack] THIS KEY
+      //            [stack] # otherwise
+      //            [stack] OBJ KEY
+      return false;
+    }
+  }
+
+  if (isSuper()) {
+    if (!bce_->emitSuperBase()) {
+      //            [stack] THIS? THIS KEY SUPERBASE
+      return false;
+    }
+  }
+  if (isIncDec() || isCompoundAssignment()) {
+    if (isSuper()) {
+      if (!bce_->emitDupAt(2, 3)) {
+        //          [stack] THIS KEY SUPERBASE THIS KEY SUPERBASE
+        return false;
+      }
+    } else {
+      if (!bce_->emit1(JSOp::Dup2)) {
+        //          [stack] OBJ KEY OBJ KEY
+        return false;
+      }
+    }
+  }
+
+  JSOp op;
+  if (isSuper()) {
+    op = JSOp::GetElemSuper;
+  } else {
+    op = JSOp::GetElem;
+  }
+  if (!bce_->emitElemOpBase(op)) {
+    //              [stack] # if Get
+    //              [stack] ELEM
+    //              [stack] # if Call
+    //              [stack] THIS ELEM
+    //              [stack] # if Inc/Dec/Assignment, with Super
+    //              [stack] THIS KEY SUPERBASE ELEM
+    //              [stack] # if Inc/Dec/Assignment, other
+    //              [stack] OBJ KEY ELEM
+    return false;
+  }
+  if (isCall()) {
+    if (!bce_->emit1(JSOp::Swap)) {
+      //            [stack] ELEM THIS
+      return false;
+    }
+  }
+
+#ifdef DEBUG
+  state_ = State::Get;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::prepareForRhs() {
+  MOZ_ASSERT(isSimpleAssignment() || isPropInit() || isCompoundAssignment());
+  MOZ_ASSERT_IF(isSimpleAssignment() || isPropInit(), state_ == State::Key);
+  MOZ_ASSERT_IF(isCompoundAssignment(), state_ == State::Get);
+
+  if (isSimpleAssignment() || isPropInit()) {
+    // For CompoundAssignment, SuperBase is already emitted by emitGet.
+    if (isSuper()) {
+      if (!bce_->emitSuperBase()) {
+        //          [stack] THIS KEY SUPERBASE
+        return false;
+      }
+    }
+  }
+
+#ifdef DEBUG
+  state_ = State::Rhs;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::skipObjAndKeyAndRhs() {
+  MOZ_ASSERT(state_ == State::Start);
+  MOZ_ASSERT(isSimpleAssignment() || isPropInit());
+
+#ifdef DEBUG
+  state_ = State::Rhs;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::emitDelete() {
+  MOZ_ASSERT(state_ == State::Key);
+  MOZ_ASSERT(isDelete());
+
+  if (isSuper()) {
+    if (!bce_->emit1(JSOp::ToPropertyKey)) {
+      //            [stack] THIS KEY
+      return false;
+    }
+    if (!bce_->emitSuperBase()) {
+      //            [stack] THIS KEY SUPERBASE
+      return false;
+    }
+
+    // Unconditionally throw when attempting to delete a super-reference.
+    if (!bce_->emit2(JSOp::ThrowMsg, uint8_t(ThrowMsgKind::CantDeleteSuper))) {
+      //            [stack] THIS KEY SUPERBASE
+      return false;
+    }
+
+    // Another wrinkle: Balance the stack from the emitter's point of view.
+    // Execution will not reach here, as the last bytecode threw.
+    if (!bce_->emitPopN(2)) {
+      //            [stack] THIS
+      return false;
+    }
+  } else {
+    JSOp op = bce_->sc->strict() ? JSOp::StrictDelElem : JSOp::DelElem;
+    if (!bce_->emitElemOpBase(op)) {
+      // SUCCEEDED
+      return false;
+    }
+  }
+
+#ifdef DEBUG
+  state_ = State::Delete;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::emitAssignment() {
+  MOZ_ASSERT(isSimpleAssignment() || isPropInit() || isCompoundAssignment());
+  MOZ_ASSERT(state_ == State::Rhs);
+
+  MOZ_ASSERT_IF(isPropInit(), !isSuper());
+
+  JSOp setOp = isPropInit() ? JSOp::InitElem
+               : isSuper()  ? bce_->sc->strict() ? JSOp::StrictSetElemSuper
+                                                 : JSOp::SetElemSuper
+               : bce_->sc->strict() ? JSOp::StrictSetElem
+                                    : JSOp::SetElem;
+  if (!bce_->emitElemOpBase(setOp)) {
+    //              [stack] ELEM
+    return false;
+  }
+
+#ifdef DEBUG
+  state_ = State::Assignment;
+#endif
+  return true;
+}
+
+bool ElemOpEmitter::emitIncDec(ValueUsage valueUsage) {
+  MOZ_ASSERT(state_ == State::Key);
+  MOZ_ASSERT(isIncDec());
+
+  if (!emitGet()) {
+    //              [stack] ... ELEM
+    return false;
+  }
+
+  MOZ_ASSERT(state_ == State::Get);
+
+  JSOp incOp = isInc() ? JSOp::Inc : JSOp::Dec;
+  if (!bce_->emit1(JSOp::ToNumeric)) {
+    //              [stack] ... N
+    return false;
+  }
+  if (isPostIncDec() && valueUsage == ValueUsage::WantValue) {
+    //              [stack] OBJ KEY SUPERBASE? N
+    if (!bce_->emit1(JSOp::Dup)) {
+      //            [stack] ... N N
+      return false;
+    }
+    if (!bce_->emit2(JSOp::Unpick, 3 + isSuper())) {
+      //            [stack] N OBJ KEY SUPERBASE? N
+      return false;
+    }
+  }
+  if (!bce_->emit1(incOp)) {
+    //              [stack] ... N+1
+    return false;
+  }
+
+  JSOp setOp =
+      isSuper()
+          ? (bce_->sc->strict() ? JSOp::StrictSetElemSuper : JSOp::SetElemSuper)
+          : (bce_->sc->strict() ? JSOp::StrictSetElem : JSOp::SetElem);
+  if (!bce_->emitElemOpBase(setOp)) {
+    //              [stack] N? N+1
+    return false;
+  }
+  if (isPostIncDec() && valueUsage == ValueUsage::WantValue) {
+    if (!bce_->emit1(JSOp::Pop)) {
+      //            [stack] N
+      return false;
+    }
+  }
+
+#ifdef DEBUG
+  state_ = State::IncDec;
+#endif
+  return true;
+}