Changeset 235419 in webkit for trunk/Source/JavaScriptCore/jit/JITExceptions.h

Timestamp:

Aug 27, 2018, 10:01:05 PM (7 years ago)

Author:

[email protected]

Message:

Fix exception throwing code so that topCallFrame and topEntryFrame stay true to their names.
​https://bugs.webkit.org/show_bug.cgi?id=188577
<rdar://problem/42985684>

Reviewed by Saam Barati.

JSTests:

• stress/regress-188577.js: Added.

Source/JavaScriptCore:

1. Introduced CallFrame::convertToStackOverflowFrame() which converts the current (top) CallFrame (which may not have a valid callee) into a StackOverflowFrame.

The StackOverflowFrame is a sentinel frame that the low level code (exception
throwing code, stack visitor, and stack unwinding code) will know to skip
over. The StackOverflowFrame will also have a valid JSCallee so that client
code can compute the globalObject or VM from this frame.

As a result, client code that throws StackOverflowErrors no longer need to
compute the caller frame to throw from: it just converts the top frame into
a StackOverflowFrame and everything should *Just Work*.

2. NativeCallFrameTracerWithRestore is now obsolete.

Instead, client code should always call convertToStackOverflowFrame() on the
frame before instantiating a NativeCallFrameTracer with it.

This means that topCallFrame will always point to the top CallFrame (which
may be a StackOverflowFrame), and topEntryFrame will always point to the top
EntryFrame. We'll never temporarily point them to the previous EntryFrame
(which we used to do with NativeCallFrameTracerWithRestore).

3. genericUnwind() and Interpreter::unwind() will now always unwind from the top CallFrame, and will know how to handle a StackOverflowFrame if they see one.

This obsoletes the UnwindStart flag.

• CMakeLists.txt:
• JavaScriptCore.xcodeproj/project.pbxproj:
• Sources.txt:
• debugger/Debugger.cpp:

(JSC::Debugger::pauseIfNeeded):

• interpreter/CallFrame.cpp:

(JSC::CallFrame::callerFrame const):
(JSC::CallFrame::unsafeCallerFrame const):
(JSC::CallFrame::convertToStackOverflowFrame):
(JSC::CallFrame::callerFrame): Deleted.
(JSC::CallFrame::unsafeCallerFrame): Deleted.

• interpreter/CallFrame.h:

(JSC::ExecState::iterate):

• interpreter/CallFrameInlines.h: Added.

(JSC::CallFrame::isStackOverflowFrame const):
(JSC::CallFrame::isWasmFrame const):

• interpreter/EntryFrame.h: Added.

(JSC::EntryFrame::vmEntryRecordOffset):
(JSC::EntryFrame::calleeSaveRegistersBufferOffset):

• interpreter/FrameTracers.h:

(JSC::NativeCallFrameTracerWithRestore::NativeCallFrameTracerWithRestore): Deleted.
(JSC::NativeCallFrameTracerWithRestore::~NativeCallFrameTracerWithRestore): Deleted.

• interpreter/Interpreter.cpp:

(JSC::Interpreter::unwind):

• interpreter/Interpreter.h:
• interpreter/StackVisitor.cpp:

(JSC::StackVisitor::StackVisitor):

• interpreter/StackVisitor.h:

(JSC::StackVisitor::visit):
(JSC::StackVisitor::topEntryFrameIsEmpty const):

• interpreter/VMEntryRecord.h:

(JSC::VMEntryRecord::callee const):
(JSC::EntryFrame::vmEntryRecordOffset): Deleted.
(JSC::EntryFrame::calleeSaveRegistersBufferOffset): Deleted.

• jit/AssemblyHelpers.h:
• jit/JITExceptions.cpp:

(JSC::genericUnwind):

• jit/JITExceptions.h:
• jit/JITOperations.cpp:
• llint/LLIntOffsetsExtractor.cpp:
• llint/LLIntSlowPaths.cpp:

(JSC::LLInt::LLINT_SLOW_PATH_DECL):

• llint/LowLevelInterpreter.asm:
• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:
• runtime/CallData.cpp:
• runtime/CommonSlowPaths.cpp:

(JSC::throwArityCheckStackOverflowError):
(JSC::SLOW_PATH_DECL):

• runtime/CommonSlowPathsExceptions.cpp: Removed.
• runtime/CommonSlowPathsExceptions.h: Removed.
• runtime/Completion.cpp:

(JSC::evaluateWithScopeExtension):

• runtime/JSGeneratorFunction.h:
• runtime/JSGlobalObject.cpp:

(JSC::JSGlobalObject::init):
(JSC::JSGlobalObject::visitChildren):

• runtime/JSGlobalObject.h:

(JSC::JSGlobalObject::stackOverflowFrameCallee const):

• runtime/VM.cpp:

(JSC::VM::throwException):

• runtime/VM.h:
• runtime/VMInlines.h:

(JSC::VM::topJSCallFrame const):

LayoutTests:

• http/tests/misc/large-js-program-expected.txt:

File:

• trunk/Source/JavaScriptCore/jit/JITExceptions.h (modified) (2 diffs)

trunk/Source/JavaScriptCore/jit/JITExceptions.h

@@ -1 +1 @@
 /*
- * Copyright (C) 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2012-2018 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -28 +28 @@
 namespace JSC {
 
-enum UnwindStart : uint8_t;
-
 class ExecState;
 class VM;
 
-void genericUnwind(VM*, ExecState*, UnwindStart);
 void genericUnwind(VM*, ExecState*);