Changeset 213107 in webkit for trunk/Source/JavaScriptCore/interpreter/Interpreter.cpp

Timestamp:

Feb 27, 2017, 5:20:54 PM (8 years ago)

Author:

[email protected]

Message:

Introduce a VM Traps mechanism and refactor Watchdog to use it.
​https://bugs.webkit.org/show_bug.cgi?id=168842

Reviewed by Filip Pizlo.

Source/JavaScriptCore:

Currently, the traps mechanism is only used for the JSC watchdog, and for
asynchronous termination requests (which is currently only used for worker
threads termination).

This first cut of the traps mechanism still relies on polling from DFG and FTL
code. This is done to keep the patch as small as possible. The work to do
a non-polling version of the traps mechanism for DFG and FTL code is deferred to
another patch.

In this patch, worker threads still need to set the VM::m_needAsynchronousTerminationSupport
flag to enable the traps polling in the DFG and FTL code. When we have the
non-polling version of the DFG and FTL traps mechanism, we can remove the use of
the VM::m_needAsynchronousTerminationSupport flag.

Note: this patch also separates asynchronous termination support from the JSC
watchdog. This separation allows us to significantly simplify the locking
requirements in the watchdog code, and make it easier to reason about its
correctness.

• CMakeLists.txt:
• JavaScriptCore.xcodeproj/project.pbxproj:
• bytecode/BytecodeList.json:
• bytecode/BytecodeUseDef.h:

(JSC::computeUsesForBytecodeOffset):
(JSC::computeDefsForBytecodeOffset):

• bytecode/CodeBlock.cpp:

(JSC::CodeBlock::dumpBytecode):

• bytecompiler/BytecodeGenerator.cpp:

(JSC::BytecodeGenerator::BytecodeGenerator):
(JSC::BytecodeGenerator::emitLoopHint):
(JSC::BytecodeGenerator::emitCheckTraps):
(JSC::BytecodeGenerator::emitWatchdog): Deleted.

• bytecompiler/BytecodeGenerator.h:
• dfg/DFGAbstractInterpreterInlines.h:

(JSC::DFG::AbstractInterpreter<AbstractStateType>::executeEffects):

• dfg/DFGByteCodeParser.cpp:

(JSC::DFG::ByteCodeParser::parseBlock):

• dfg/DFGCapabilities.cpp:

(JSC::DFG::capabilityLevel):

• dfg/DFGClobberize.h:

(JSC::DFG::clobberize):

• dfg/DFGDoesGC.cpp:

(JSC::DFG::doesGC):

• dfg/DFGFixupPhase.cpp:

(JSC::DFG::FixupPhase::fixupNode):

• dfg/DFGNodeType.h:
• dfg/DFGPredictionPropagationPhase.cpp:
• dfg/DFGSafeToExecute.h:

(JSC::DFG::safeToExecute):

• dfg/DFGSpeculativeJIT.cpp:

(JSC::DFG::SpeculativeJIT::compileCheckTraps):

• dfg/DFGSpeculativeJIT.h:
• dfg/DFGSpeculativeJIT32_64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• dfg/DFGSpeculativeJIT64.cpp:

(JSC::DFG::SpeculativeJIT::compile):

• ftl/FTLCapabilities.cpp:

(JSC::FTL::canCompile):

• ftl/FTLLowerDFGToB3.cpp:

(JSC::FTL::DFG::LowerDFGToB3::compileNode):
(JSC::FTL::DFG::LowerDFGToB3::compileCheckTraps):
(JSC::FTL::DFG::LowerDFGToB3::compileCheckWatchdogTimer): Deleted.

• interpreter/Interpreter.cpp:

(JSC::Interpreter::executeProgram):
(JSC::Interpreter::executeCall):
(JSC::Interpreter::executeConstruct):
(JSC::Interpreter::execute):

• jit/JIT.cpp:

(JSC::JIT::privateCompileMainPass):
(JSC::JIT::privateCompileSlowCases):

• jit/JIT.h:
• jit/JITOpcodes.cpp:

(JSC::JIT::emit_op_check_traps):
(JSC::JIT::emitSlow_op_check_traps):
(JSC::JIT::emit_op_watchdog): Deleted.
(JSC::JIT::emitSlow_op_watchdog): Deleted.

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

(JSC::LLInt::LLINT_SLOW_PATH_DECL):

• llint/LLIntSlowPaths.h:
• llint/LowLevelInterpreter.asm:
• llint/LowLevelInterpreter32_64.asm:
• llint/LowLevelInterpreter64.asm:
• runtime/VM.cpp:

(JSC::VM::~VM):
(JSC::VM::ensureWatchdog):
(JSC::VM::handleTraps):

• runtime/VM.h:

(JSC::VM::ownerThread):
(JSC::VM::needTrapHandling):
(JSC::VM::needTrapHandlingAddress):
(JSC::VM::notifyNeedTermination):
(JSC::VM::notifyNeedWatchdogCheck):
(JSC::VM::needAsynchronousTerminationSupport):
(JSC::VM::setNeedAsynchronousTerminationSupport):

• runtime/VMInlines.h:

(JSC::VM::shouldTriggerTermination): Deleted.

• runtime/VMTraps.cpp: Added.

(JSC::VMTraps::fireTrap):
(JSC::VMTraps::takeTrap):

• runtime/VMTraps.h: Added.

(JSC::VMTraps::needTrapHandling):
(JSC::VMTraps::needTrapHandlingAddress):
(JSC::VMTraps::hasTrapForEvent):
(JSC::VMTraps::setTrapForEvent):
(JSC::VMTraps::clearTrapForEvent):

• runtime/Watchdog.cpp:

(JSC::Watchdog::Watchdog):
(JSC::Watchdog::setTimeLimit):
(JSC::Watchdog::shouldTerminate):
(JSC::Watchdog::enteredVM):
(JSC::Watchdog::exitedVM):
(JSC::Watchdog::startTimer):
(JSC::Watchdog::stopTimer):
(JSC::Watchdog::willDestroyVM):
(JSC::Watchdog::terminateSoon): Deleted.
(JSC::Watchdog::shouldTerminateSlow): Deleted.

• runtime/Watchdog.h:

(JSC::Watchdog::shouldTerminate): Deleted.
(JSC::Watchdog::timerDidFireAddress): Deleted.

Source/WebCore:

No new tests needed because this is a re-implementation of existing functionality.

• bindings/js/WorkerScriptController.cpp:

(WebCore::WorkerScriptController::WorkerScriptController):
(WebCore::WorkerScriptController::scheduleExecutionTermination):

File:

• trunk/Source/JavaScriptCore/interpreter/Interpreter.cpp (modified) (6 diffs)

trunk/Source/JavaScriptCore/interpreter/Interpreter.cpp

@@ -861 +861 @@
     }
 
-    if (UNLIKELY(vm.shouldTriggerTermination(callFrame)))
-        return throwTerminatedExecutionException(callFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(callFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     if (scope->structure()->isUncacheableDictionary())
@@ -919 +921 @@
         newCodeBlock = 0;
 
-    if (UNLIKELY(vm.shouldTriggerTermination(callFrame)))
-        return throwTerminatedExecutionException(callFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(callFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     ProtoCallFrame protoCallFrame;
@@ -982 +986 @@
         newCodeBlock = 0;
 
-    if (UNLIKELY(vm.shouldTriggerTermination(callFrame)))
-        return throwTerminatedExecutionException(callFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(callFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     ProtoCallFrame protoCallFrame;
@@ -1044 +1050 @@
     StackStats::CheckPoint stackCheckPoint;
 
-    if (UNLIKELY(vm.shouldTriggerTermination(closure.oldCallFrame)))
-        return throwTerminatedExecutionException(closure.oldCallFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(closure.oldCallFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     // Execute the code:
@@ -1145 +1153 @@
     }
 
-    if (UNLIKELY(vm.shouldTriggerTermination(callFrame)))
-        return throwTerminatedExecutionException(callFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(callFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     ASSERT(codeBlock->numParameters() == 1); // 1 parameter for 'this'.
@@ -1184 +1194 @@
     }
 
-    if (UNLIKELY(vm.shouldTriggerTermination(callFrame)))
-        return throwTerminatedExecutionException(callFrame, throwScope);
+    if (UNLIKELY(vm.needTrapHandling())) {
+        vm.handleTraps(callFrame);
+        RETURN_IF_EXCEPTION(throwScope, throwScope.exception());
+    }
 
     if (scope->structure()->isUncacheableDictionary())