Changeset 277974 in webkit for trunk/Source/JavaScriptCore/jit/SlowPathCall.cpp

Timestamp:

May 24, 2021, 3:34:19 PM (4 years ago)

Author:

[email protected]

Message:

Allow CTI stubs to be generated off the main thread
​https://bugs.webkit.org/show_bug.cgi?id=226180

Reviewed by Mark Lam.

We make this work by tracking if we're a compiler thread when generating
the CTI stub. If so, it means that the main thread needs to issue a
crossModifyingCodeFence when it's going to run the CTI stub for the first
time.

This patch also does away with pre-generating thunks. Thunks can now generate
other thunks while they're running. To do this, we make JITThunks lock a
recursive lock. The reason this is ok is that we don't have any recursive
thunks in the thunk graph. It's a DAG.

• dfg/DFGDriver.cpp:

(JSC::DFG::compileImpl):

• jit/JITOpcodes.cpp:

(JSC::JIT::op_check_traps_handlerGenerator):

• jit/JITPropertyAccess.cpp:

(JSC::JIT::slow_op_get_from_scopeGenerator):
(JSC::JIT::slow_op_put_to_scopeGenerator):

• jit/JITThunks.cpp:

(JSC::JITThunks::ctiInternalFunctionCall):
(JSC::JITThunks::ctiInternalFunctionConstruct):
(JSC::JITThunks::ctiStubImpl):
(JSC::JITThunks::ctiStub):
(JSC::JITThunks::ctiSlowPathFunctionStub):
(JSC::JITThunks::existingCTIStub): Deleted.
(JSC::JITThunks::preinitializeCTIThunks): Deleted.

• jit/JITThunks.h:
• jit/SlowPathCall.cpp:

(JSC::JITSlowPathCall::generateThunk):

• jit/ThunkGenerators.cpp:

(JSC::popThunkStackPreservesAndHandleExceptionGenerator):
(JSC::checkExceptionGenerator):
(JSC::virtualThunkFor):

• runtime/VM.cpp:

(JSC::VM::VM):
(JSC::VM::getCTIInternalFunctionTrampolineFor):

• runtime/VM.h:

File:

• trunk/Source/JavaScriptCore/jit/SlowPathCall.cpp (modified) (1 diff)

trunk/Source/JavaScriptCore/jit/SlowPathCall.cpp

@@ -85 +85 @@
     jit.ret();
 
-    auto handler = vm.jitStubs->existingCTIStub(popThunkStackPreservesAndHandleExceptionGenerator, NoLockingNecessary);
+    auto handler = vm.getCTIStub(popThunkStackPreservesAndHandleExceptionGenerator);
 
     LinkBuffer patchBuffer(jit, GLOBAL_THUNK_ID, LinkBuffer::Profile::ExtraCTIThunk);