Adding upstream version 1:115.7.0.upstream/1%115.7.0upstream

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

1 files changed, 586 insertions, 0 deletions

diff --git a/js/src/vm/FrameIter.h b/js/src/vm/FrameIter.h
new file mode 100644
index 0000000000..c3561e0247
--- /dev/null
+++ b/js/src/vm/FrameIter.h
@@ -0,0 +1,586 @@
+/* -*- 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/. */
+
+#ifndef vm_FrameIter_h
+#define vm_FrameIter_h
+
+#include "mozilla/Assertions.h"  // MOZ_ASSERT
+#include "mozilla/Attributes.h"  // MOZ_IMPLICIT, MOZ_RAII
+#include "mozilla/MaybeOneOf.h"  // mozilla::MaybeOneOf
+
+#include <stddef.h>  // size_t
+#include <stdint.h>  // uint8_t, uint32_t, uintptr_t
+
+#include "jstypes.h"  // JS_PUBLIC_API
+
+#include "jit/JSJitFrameIter.h"  // js::jit::{InlineFrameIterator,JSJitFrameIter}
+#include "js/RootingAPI.h"       // JS::Handle, JS::Rooted
+#include "js/TypeDecls.h"  // jsbytecode, JSContext, JSAtom, JSFunction, JSObject, JSScript
+#include "js/Value.h"       // JS::Value
+#include "vm/Activation.h"  // js::InterpreterActivation
+#include "vm/Stack.h"       // js::{AbstractFramePtr,MaybeCheckAliasing}
+#include "wasm/WasmFrameIter.h"  // js::wasm::{ExitReason,RegisterState,WasmFrameIter}
+
+struct JSPrincipals;
+
+namespace JS {
+
+class JS_PUBLIC_API Compartment;
+class JS_PUBLIC_API Realm;
+
+}  // namespace JS
+
+namespace js {
+
+class ArgumentsObject;
+class CallObject;
+
+namespace jit {
+class CommonFrameLayout;
+class JitActivation;
+}  // namespace jit
+
+namespace wasm {
+class Instance;
+}  // namespace wasm
+
+// Iterates over the frames of a single InterpreterActivation.
+class InterpreterFrameIterator {
+  InterpreterActivation* activation_;
+  InterpreterFrame* fp_;
+  jsbytecode* pc_;
+  JS::Value* sp_;
+
+ public:
+  explicit InterpreterFrameIterator(InterpreterActivation* activation)
+      : activation_(activation), fp_(nullptr), pc_(nullptr), sp_(nullptr) {
+    if (activation) {
+      fp_ = activation->current();
+      pc_ = activation->regs().pc;
+      sp_ = activation->regs().sp;
+    }
+  }
+
+  InterpreterFrame* frame() const {
+    MOZ_ASSERT(!done());
+    return fp_;
+  }
+  jsbytecode* pc() const {
+    MOZ_ASSERT(!done());
+    return pc_;
+  }
+  JS::Value* sp() const {
+    MOZ_ASSERT(!done());
+    return sp_;
+  }
+
+  InterpreterFrameIterator& operator++();
+
+  bool done() const { return fp_ == nullptr; }
+};
+
+// A JitFrameIter can iterate over all kind of frames emitted by our code
+// generators, be they composed of JS jit frames or wasm frames, interleaved or
+// not, in any order.
+//
+// In the following class:
+// - code generated for JS is referred to as JSJit.
+// - code generated for wasm is referred to as Wasm.
+// Also, Jit refers to any one of them.
+//
+// JitFrameIter uses JSJitFrameIter to iterate over JSJit code or a
+// WasmFrameIter to iterate over wasm code; only one of them is active at the
+// time. When a sub-iterator is done, the JitFrameIter knows how to stop, move
+// onto the next activation or move onto another kind of Jit code.
+//
+// For ease of use, there is also OnlyJSJitFrameIter, which skips all the
+// non-JSJit frames.
+//
+// Note it is allowed to get a handle to the internal frame iterator via
+// asJSJit() and asWasm(), but the user has to be careful not to have those be
+// used after JitFrameIter leaves the scope or the operator++ is called.
+//
+// In particular, this can handle the transition from wasm to jit and from jit
+// to wasm, since these can be interleaved in the same JitActivation.
+class JitFrameIter {
+ protected:
+  jit::JitActivation* act_ = nullptr;
+  mozilla::MaybeOneOf<jit::JSJitFrameIter, wasm::WasmFrameIter> iter_ = {};
+  bool mustUnwindActivation_ = false;
+
+  void settle();
+
+ public:
+  JitFrameIter() = default;
+
+  explicit JitFrameIter(jit::JitActivation* activation,
+                        bool mustUnwindActivation = false);
+
+  explicit JitFrameIter(const JitFrameIter& another);
+  JitFrameIter& operator=(const JitFrameIter& another);
+
+  bool isSome() const { return !iter_.empty(); }
+  void reset() {
+    MOZ_ASSERT(isSome());
+    iter_.destroy();
+  }
+
+  bool isJSJit() const {
+    return isSome() && iter_.constructed<jit::JSJitFrameIter>();
+  }
+  jit::JSJitFrameIter& asJSJit() { return iter_.ref<jit::JSJitFrameIter>(); }
+  const jit::JSJitFrameIter& asJSJit() const {
+    return iter_.ref<jit::JSJitFrameIter>();
+  }
+
+  bool isWasm() const {
+    return isSome() && iter_.constructed<wasm::WasmFrameIter>();
+  }
+  wasm::WasmFrameIter& asWasm() { return iter_.ref<wasm::WasmFrameIter>(); }
+  const wasm::WasmFrameIter& asWasm() const {
+    return iter_.ref<wasm::WasmFrameIter>();
+  }
+
+  // Operations common to all frame iterators.
+  const jit::JitActivation* activation() const { return act_; }
+  bool done() const;
+  void operator++();
+
+  JS::Realm* realm() const;
+
+  // Returns the address of the next instruction that will execute in this
+  // frame, once control returns to this frame.
+  uint8_t* resumePCinCurrentFrame() const;
+
+  // Operations which have an effect only on JIT frames.
+  void skipNonScriptedJSFrames();
+
+  // Returns true iff this is a JIT frame with a self-hosted script. Note: be
+  // careful, JitFrameIter does not consider functions inlined by Ion.
+  bool isSelfHostedIgnoringInlining() const;
+};
+
+// A JitFrameIter that skips all the non-JSJit frames, skipping interleaved
+// frames of any another kind.
+
+class OnlyJSJitFrameIter : public JitFrameIter {
+  void settle() {
+    while (!done() && !isJSJit()) {
+      JitFrameIter::operator++();
+    }
+  }
+
+ public:
+  explicit OnlyJSJitFrameIter(jit::JitActivation* act);
+  explicit OnlyJSJitFrameIter(const ActivationIterator& cx);
+
+  void operator++() {
+    JitFrameIter::operator++();
+    settle();
+  }
+
+  const jit::JSJitFrameIter& frame() const { return asJSJit(); }
+};
+
+class ScriptSource;
+
+// A FrameIter walks over a context's stack of JS script activations,
+// abstracting over whether the JS scripts were running in the interpreter or
+// different modes of compiled code.
+//
+// FrameIter is parameterized by what it includes in the stack iteration:
+//  - When provided, the optional JSPrincipal argument will cause FrameIter to
+//    only show frames in globals whose JSPrincipals are subsumed (via
+//    JSSecurityCallbacks::subsume) by the given JSPrincipal.
+//
+// Additionally, there are derived FrameIter types that automatically skip
+// certain frames:
+//  - ScriptFrameIter only shows frames that have an associated JSScript
+//    (currently everything other than wasm stack frames). When !hasScript(),
+//    clients must stick to the portion of the
+//    interface marked below.
+//  - NonBuiltinScriptFrameIter additionally filters out builtin (self-hosted)
+//    scripts.
+class FrameIter {
+ public:
+  enum DebuggerEvalOption {
+    FOLLOW_DEBUGGER_EVAL_PREV_LINK,
+    IGNORE_DEBUGGER_EVAL_PREV_LINK
+  };
+
+  enum State {
+    DONE,    // when there are no more frames nor activations to unwind.
+    INTERP,  // interpreter activation on the stack
+    JIT      // jit or wasm activations on the stack
+  };
+
+  // Unlike ScriptFrameIter itself, ScriptFrameIter::Data can be allocated on
+  // the heap, so this structure should not contain any GC things.
+  struct Data {
+    JSContext* cx_;
+    DebuggerEvalOption debuggerEvalOption_;
+    JSPrincipals* principals_;
+
+    State state_;
+
+    jsbytecode* pc_;
+
+    InterpreterFrameIterator interpFrames_;
+    ActivationIterator activations_;
+
+    JitFrameIter jitFrames_;
+    unsigned ionInlineFrameNo_;
+
+    Data(JSContext* cx, DebuggerEvalOption debuggerEvalOption,
+         JSPrincipals* principals);
+    Data(const Data& other);
+  };
+
+  explicit FrameIter(JSContext* cx,
+                     DebuggerEvalOption = FOLLOW_DEBUGGER_EVAL_PREV_LINK);
+  FrameIter(JSContext* cx, DebuggerEvalOption, JSPrincipals*);
+  FrameIter(const FrameIter& iter);
+  MOZ_IMPLICIT FrameIter(const Data& data);
+  MOZ_IMPLICIT FrameIter(AbstractFramePtr frame);
+
+  bool done() const { return data_.state_ == DONE; }
+
+  // -------------------------------------------------------
+  // The following functions can only be called when !done()
+  // -------------------------------------------------------
+
+  FrameIter& operator++();
+
+  JS::Realm* realm() const;
+  JS::Compartment* compartment() const;
+  Activation* activation() const { return data_.activations_.activation(); }
+
+  bool isInterp() const {
+    MOZ_ASSERT(!done());
+    return data_.state_ == INTERP;
+  }
+  bool isJSJit() const {
+    MOZ_ASSERT(!done());
+    return data_.state_ == JIT && data_.jitFrames_.isJSJit();
+  }
+  bool isWasm() const {
+    MOZ_ASSERT(!done());
+    return data_.state_ == JIT && data_.jitFrames_.isWasm();
+  }
+
+  inline bool isIon() const;
+  inline bool isBaseline() const;
+  inline bool isPhysicalJitFrame() const;
+
+  bool isEvalFrame() const;
+  bool isModuleFrame() const;
+  bool isFunctionFrame() const;
+  bool hasArgs() const { return isFunctionFrame(); }
+
+  ScriptSource* scriptSource() const;
+  const char* filename() const;
+  const char16_t* displayURL() const;
+  unsigned computeLine(uint32_t* column = nullptr) const;
+  JSAtom* maybeFunctionDisplayAtom() const;
+  bool mutedErrors() const;
+
+  bool hasScript() const { return !isWasm(); }
+
+  // -----------------------------------------------------------
+  //  The following functions can only be called when isWasm()
+  // -----------------------------------------------------------
+
+  inline bool wasmDebugEnabled() const;
+  inline wasm::Instance* wasmInstance() const;
+  inline uint32_t wasmFuncIndex() const;
+  inline unsigned wasmBytecodeOffset() const;
+  void wasmUpdateBytecodeOffset();
+
+  // -----------------------------------------------------------
+  // The following functions can only be called when hasScript()
+  // -----------------------------------------------------------
+
+  inline JSScript* script() const;
+
+  bool isConstructing() const;
+  jsbytecode* pc() const {
+    MOZ_ASSERT(!done());
+    return data_.pc_;
+  }
+  void updatePcQuadratic();
+
+  // The function |calleeTemplate()| returns either the function from which
+  // the current |callee| was cloned or the |callee| if it can be read. As
+  // long as we do not have to investigate the environment chain or build a
+  // new frame, we should prefer to use |calleeTemplate| instead of
+  // |callee|, as requesting the |callee| might cause the invalidation of
+  // the frame. (see js::Lambda)
+  JSFunction* calleeTemplate() const;
+  JSFunction* callee(JSContext* cx) const;
+
+  JSFunction* maybeCallee(JSContext* cx) const {
+    return isFunctionFrame() ? callee(cx) : nullptr;
+  }
+
+  bool matchCallee(JSContext* cx, JS::Handle<JSFunction*> fun) const;
+
+  unsigned numActualArgs() const;
+  unsigned numFormalArgs() const;
+  JS::Value unaliasedActual(unsigned i,
+                            MaybeCheckAliasing = CHECK_ALIASING) const;
+  template <class Op>
+  inline void unaliasedForEachActual(JSContext* cx, Op op);
+
+  JSObject* environmentChain(JSContext* cx) const;
+  bool hasInitialEnvironment(JSContext* cx) const;
+  CallObject& callObj(JSContext* cx) const;
+
+  bool hasArgsObj() const;
+  ArgumentsObject& argsObj() const;
+
+  // Get the original |this| value passed to this function. May not be the
+  // actual this-binding (for instance, derived class constructors will
+  // change their this-value later and non-strict functions will box
+  // primitives).
+  JS::Value thisArgument(JSContext* cx) const;
+
+  JS::Value returnValue() const;
+  void setReturnValue(const JS::Value& v);
+
+  // These are only valid for the top frame.
+  size_t numFrameSlots() const;
+  JS::Value frameSlotValue(size_t index) const;
+
+  // Ensures that we have rematerialized the top frame and its associated
+  // inline frames. Can only be called when isIon().
+  bool ensureHasRematerializedFrame(JSContext* cx);
+
+  // True when isInterp() or isBaseline(). True when isIon() if it
+  // has a rematerialized frame. False otherwise.
+  bool hasUsableAbstractFramePtr() const;
+
+  // -----------------------------------------------------------
+  // The following functions can only be called when isInterp(),
+  // isBaseline(), isWasm() or isIon(). Further, abstractFramePtr() can
+  // only be called when hasUsableAbstractFramePtr().
+  // -----------------------------------------------------------
+
+  AbstractFramePtr abstractFramePtr() const;
+  Data* copyData() const;
+
+  // This can only be called when isInterp():
+  inline InterpreterFrame* interpFrame() const;
+
+  // This can only be called when isPhysicalJitFrame():
+  inline jit::CommonFrameLayout* physicalJitFrame() const;
+
+  // This is used to provide a raw interface for debugging.
+  void* rawFramePtr() const;
+
+  bool inPrologue() const;
+
+ private:
+  Data data_;
+  jit::InlineFrameIterator ionInlineFrames_;
+
+  const jit::JSJitFrameIter& jsJitFrame() const {
+    return data_.jitFrames_.asJSJit();
+  }
+  const wasm::WasmFrameIter& wasmFrame() const {
+    return data_.jitFrames_.asWasm();
+  }
+
+  jit::JSJitFrameIter& jsJitFrame() { return data_.jitFrames_.asJSJit(); }
+  wasm::WasmFrameIter& wasmFrame() { return data_.jitFrames_.asWasm(); }
+
+  bool isIonScripted() const {
+    return isJSJit() && jsJitFrame().isIonScripted();
+  }
+
+  bool principalsSubsumeFrame() const;
+
+  void popActivation();
+  void popInterpreterFrame();
+  void nextJitFrame();
+  void popJitFrame();
+  void settleOnActivation();
+};
+
+class ScriptFrameIter : public FrameIter {
+  void settle() {
+    while (!done() && !hasScript()) {
+      FrameIter::operator++();
+    }
+  }
+
+ public:
+  explicit ScriptFrameIter(
+      JSContext* cx,
+      DebuggerEvalOption debuggerEvalOption = FOLLOW_DEBUGGER_EVAL_PREV_LINK)
+      : FrameIter(cx, debuggerEvalOption) {
+    settle();
+  }
+
+  ScriptFrameIter& operator++() {
+    FrameIter::operator++();
+    settle();
+    return *this;
+  }
+};
+
+#ifdef DEBUG
+bool SelfHostedFramesVisible();
+#else
+static inline bool SelfHostedFramesVisible() { return false; }
+#endif
+
+/* A filtering of the FrameIter to only stop at non-self-hosted scripts. */
+class NonBuiltinFrameIter : public FrameIter {
+  void settle();
+
+ public:
+  explicit NonBuiltinFrameIter(
+      JSContext* cx, FrameIter::DebuggerEvalOption debuggerEvalOption =
+                         FrameIter::FOLLOW_DEBUGGER_EVAL_PREV_LINK)
+      : FrameIter(cx, debuggerEvalOption) {
+    settle();
+  }
+
+  NonBuiltinFrameIter(JSContext* cx,
+                      FrameIter::DebuggerEvalOption debuggerEvalOption,
+                      JSPrincipals* principals)
+      : FrameIter(cx, debuggerEvalOption, principals) {
+    settle();
+  }
+
+  NonBuiltinFrameIter(JSContext* cx, JSPrincipals* principals)
+      : FrameIter(cx, FrameIter::FOLLOW_DEBUGGER_EVAL_PREV_LINK, principals) {
+    settle();
+  }
+
+  NonBuiltinFrameIter& operator++() {
+    FrameIter::operator++();
+    settle();
+    return *this;
+  }
+};
+
+// A filtering of the ScriptFrameIter to only stop at non-self-hosted scripts.
+class NonBuiltinScriptFrameIter : public ScriptFrameIter {
+  void settle();
+
+ public:
+  explicit NonBuiltinScriptFrameIter(
+      JSContext* cx, ScriptFrameIter::DebuggerEvalOption debuggerEvalOption =
+                         ScriptFrameIter::FOLLOW_DEBUGGER_EVAL_PREV_LINK)
+      : ScriptFrameIter(cx, debuggerEvalOption) {
+    settle();
+  }
+
+  NonBuiltinScriptFrameIter& operator++() {
+    ScriptFrameIter::operator++();
+    settle();
+    return *this;
+  }
+};
+
+/*
+ * Blindly iterate over all frames in the current thread's stack. These frames
+ * can be from different contexts and compartments, so beware.
+ */
+class AllFramesIter : public FrameIter {
+ public:
+  explicit AllFramesIter(JSContext* cx)
+      : FrameIter(cx, ScriptFrameIter::IGNORE_DEBUGGER_EVAL_PREV_LINK) {}
+};
+
+/* Iterates over all script frame in the current thread's stack.
+ * See also AllFramesIter and ScriptFrameIter.
+ */
+class AllScriptFramesIter : public ScriptFrameIter {
+ public:
+  explicit AllScriptFramesIter(JSContext* cx)
+      : ScriptFrameIter(cx, ScriptFrameIter::IGNORE_DEBUGGER_EVAL_PREV_LINK) {}
+};
+
+/* Popular inline definitions. */
+
+inline JSScript* FrameIter::script() const {
+  MOZ_ASSERT(!done());
+  MOZ_ASSERT(hasScript());
+  if (data_.state_ == INTERP) {
+    return interpFrame()->script();
+  }
+  if (jsJitFrame().isIonJS()) {
+    return ionInlineFrames_.script();
+  }
+  return jsJitFrame().script();
+}
+
+inline bool FrameIter::wasmDebugEnabled() const {
+  MOZ_ASSERT(!done());
+  MOZ_ASSERT(isWasm());
+  return wasmFrame().debugEnabled();
+}
+
+inline wasm::Instance* FrameIter::wasmInstance() const {
+  MOZ_ASSERT(!done());
+  MOZ_ASSERT(isWasm());
+  return wasmFrame().instance();
+}
+
+inline unsigned FrameIter::wasmBytecodeOffset() const {
+  MOZ_ASSERT(!done());
+  MOZ_ASSERT(isWasm());
+  return wasmFrame().lineOrBytecode();
+}
+
+inline uint32_t FrameIter::wasmFuncIndex() const {
+  MOZ_ASSERT(!done());
+  MOZ_ASSERT(isWasm());
+  return wasmFrame().funcIndex();
+}
+
+inline bool FrameIter::isIon() const {
+  return isJSJit() && jsJitFrame().isIonJS();
+}
+
+inline bool FrameIter::isBaseline() const {
+  return isJSJit() && jsJitFrame().isBaselineJS();
+}
+
+inline InterpreterFrame* FrameIter::interpFrame() const {
+  MOZ_ASSERT(data_.state_ == INTERP);
+  return data_.interpFrames_.frame();
+}
+
+inline bool FrameIter::isPhysicalJitFrame() const {
+  if (!isJSJit()) {
+    return false;
+  }
+
+  auto& jitFrame = jsJitFrame();
+
+  if (jitFrame.isBaselineJS()) {
+    return true;
+  }
+
+  if (jitFrame.isIonScripted()) {
+    // Only the bottom of a group of inlined Ion frames is a physical frame.
+    return ionInlineFrames_.frameNo() == 0;
+  }
+
+  return false;
+}
+
+inline jit::CommonFrameLayout* FrameIter::physicalJitFrame() const {
+  MOZ_ASSERT(isPhysicalJitFrame());
+  return jsJitFrame().current();
+}
+
+}  // namespace js
+
+#endif  // vm_FrameIter_h