Changeset 122392 in webkit for trunk/Source/JavaScriptCore/bytecode/CodeOrigin.h

Timestamp:

Jul 11, 2012, 5:12:03 PM (13 years ago)

Author:

[email protected]

Message:

DFG should have fast virtual calls
​https://bugs.webkit.org/show_bug.cgi?id=90924

Source/JavaScriptCore:

Reviewed by Gavin Barraclough.

Implements virtual call support in the style of the old JIT, with the
caveat that we still use the same slow path for both InternalFunction
calls and JSFunction calls. Also rationalized the way that our
CodeOrigin indices tie into exception checks (previously it was a
strange one-to-one mapping with fairly limited assertions; now it's a
one-to-many mapping for CodeOrigins to exception checks, respectively).
I also took the opportunity to clean up
CallLinkInfo::callReturnLocation, which previously was either a Call or
a NearCall. Now it's just a NearCall. As well, exceptions during slow
path call resolution are now handled by returning an exception throwing
thunk rather than returning null. And finally, I made a few things
public that were previously private-with-lots-of-friends, because I
truly despise the thought of listing each thunk generating function as
a friend of JSValue and friends.

• bytecode/CallLinkInfo.cpp:

(JSC::CallLinkInfo::unlink):

• bytecode/CallLinkInfo.h:

(CallLinkInfo):

• bytecode/CodeOrigin.h:

(JSC::CodeOrigin::CodeOrigin):
(JSC::CodeOrigin::isSet):

• dfg/DFGAssemblyHelpers.h:

(JSC::DFG::AssemblyHelpers::AssemblyHelpers):

• dfg/DFGCCallHelpers.h:

(JSC::DFG::CCallHelpers::CCallHelpers):

• dfg/DFGGPRInfo.h:

(GPRInfo):

• dfg/DFGJITCompiler.cpp:

(JSC::DFG::JITCompiler::link):
(JSC::DFG::JITCompiler::compileFunction):

• dfg/DFGJITCompiler.h:

(JSC::DFG::CallBeginToken::CallBeginToken):
(JSC::DFG::CallBeginToken::~CallBeginToken):
(CallBeginToken):
(JSC::DFG::CallBeginToken::set):
(JSC::DFG::CallBeginToken::registerWithExceptionCheck):
(JSC::DFG::CallBeginToken::codeOrigin):
(JSC::DFG::CallExceptionRecord::CallExceptionRecord):
(CallExceptionRecord):
(JSC::DFG::JITCompiler::currentCodeOriginIndex):
(JITCompiler):
(JSC::DFG::JITCompiler::beginCall):
(JSC::DFG::JITCompiler::notifyCall):
(JSC::DFG::JITCompiler::prepareForExceptionCheck):
(JSC::DFG::JITCompiler::addExceptionCheck):
(JSC::DFG::JITCompiler::addFastExceptionCheck):

• dfg/DFGOperations.cpp:
• dfg/DFGRepatch.cpp:

(JSC::DFG::dfgLinkFor):

• dfg/DFGSpeculativeJIT.h:

(JSC::DFG::SpeculativeJIT::appendCallWithExceptionCheck):

• dfg/DFGSpeculativeJIT32_64.cpp:

(JSC::DFG::SpeculativeJIT::emitCall):

• dfg/DFGSpeculativeJIT64.cpp:

(JSC::DFG::SpeculativeJIT::emitCall):

• dfg/DFGThunks.cpp:

(JSC::DFG::emitPointerValidation):
(DFG):
(JSC::DFG::throwExceptionFromCallSlowPathGenerator):
(JSC::DFG::slowPathFor):
(JSC::DFG::linkForThunkGenerator):
(JSC::DFG::linkCallThunkGenerator):
(JSC::DFG::linkConstructThunkGenerator):
(JSC::DFG::virtualForThunkGenerator):
(JSC::DFG::virtualCallThunkGenerator):
(JSC::DFG::virtualConstructThunkGenerator):

• dfg/DFGThunks.h:

(DFG):

• jit/JIT.cpp:

(JSC::JIT::privateCompile):
(JSC::JIT::linkFor):

• runtime/Executable.h:

(ExecutableBase):
(JSC::ExecutableBase::offsetOfJITCodeFor):
(JSC::ExecutableBase::offsetOfNumParametersFor):

• runtime/JSValue.h:

(JSValue):

LayoutTests:

Rubber stamped by Oliver Hunt.

This changes which piece of code appears on top of the stack at the point of a stack
overflow. As far as Oliver and I can tell, it doesn't matter, so I just rebased the
test.

• fast/js/stack-trace-expected.txt:

File:

• trunk/Source/JavaScriptCore/bytecode/CodeOrigin.h (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecode/CodeOrigin.h

@@ -40 +40 @@
 
 struct CodeOrigin {
+    static const unsigned maximumBytecodeIndex = (1u << 29) - 1;
+    
     // Bytecode offset that you'd use to re-execute this instruction.
     unsigned bytecodeIndex : 29;
@@ -49 +51 @@
     
     CodeOrigin()
-        : bytecodeIndex(std::numeric_limits<uint32_t>::max())
+        : bytecodeIndex(maximumBytecodeIndex)
         , valueProfileOffset(0)
         , inlineCallFrame(0)
@@ -60 +62 @@
         , inlineCallFrame(inlineCallFrame)
     {
-        ASSERT(bytecodeIndex < (1u << 29));
+        ASSERT(bytecodeIndex <= maximumBytecodeIndex);
         ASSERT(valueProfileOffset < (1u << 3));
     }
     
-    bool isSet() const { return bytecodeIndex != std::numeric_limits<uint32_t>::max(); }
+    bool isSet() const { return bytecodeIndex != maximumBytecodeIndex; }
     
     unsigned bytecodeIndexForValueProfile() const