Changeset 44700 in webkit for trunk/JavaScriptCore/jit/JIT.cpp

Timestamp:

Jun 15, 2009, 5:26:53 PM (16 years ago)

Author:

[email protected]

Message:

2009-06-15 Gavin Barraclough <​[email protected]>

Reviewed by Oliver Hunt.

Move repatching methods into a set of methods on a class. This will allow us to
coallesce memory reprotection calls. Really, we want this class to be called
PatchBuffer, we want the class PatchBuffer to be called LinkBuffer, we want both
to be memblers of MacroAssembler rather then AbstractMacroAssembler, we don't
want the CodeLocationFoo types anymore (they are now only really there to provide
type safety, and that is completely undermined by the way we use offsets). Then
the link & patch buffers should delegate the actual patching calls to the
architecture-specific layer of the MacroAssembler. Landing all these changes as a
sequence of patches.

No performance impact.

• assembler/AbstractMacroAssembler.h: (JSC::AbstractMacroAssembler::CodeLocationCall::CodeLocationCall): (JSC::AbstractMacroAssembler::CodeLocationNearCall::CodeLocationNearCall): (JSC::AbstractMacroAssembler::CodeLocationNearCall::calleeReturnAddressValue): (JSC::AbstractMacroAssembler::RepatchBuffer::RepatchBuffer): (JSC::AbstractMacroAssembler::RepatchBuffer::relink): (JSC::AbstractMacroAssembler::RepatchBuffer::repatch): (JSC::AbstractMacroAssembler::RepatchBuffer::relinkCallerToTrampoline): (JSC::AbstractMacroAssembler::RepatchBuffer::relinkCallerToFunction): (JSC::AbstractMacroAssembler::RepatchBuffer::relinkNearCallerToTrampoline): (JSC::AbstractMacroAssembler::RepatchBuffer::repatchLoadPtrToLEA):
• jit/JIT.cpp: (JSC::ctiPatchNearCallByReturnAddress): (JSC::ctiPatchCallByReturnAddress): (JSC::JIT::unlinkCall): (JSC::JIT::linkCall):
• jit/JITPropertyAccess.cpp: (JSC::JIT::privateCompilePutByIdTransition): (JSC::JIT::patchGetByIdSelf): (JSC::JIT::patchMethodCallProto): (JSC::JIT::patchPutByIdReplace): (JSC::JIT::privateCompilePatchGetArrayLength): (JSC::JIT::privateCompileGetByIdProto): (JSC::JIT::privateCompileGetByIdSelfList): (JSC::JIT::privateCompileGetByIdProtoList): (JSC::JIT::privateCompileGetByIdChainList): (JSC::JIT::privateCompileGetByIdChain):

File:

• trunk/JavaScriptCore/jit/JIT.cpp (modified) (3 diffs)

trunk/JavaScriptCore/jit/JIT.cpp

@@ -49 +49 @@
 void ctiPatchNearCallByReturnAddress(MacroAssembler::ProcessorReturnAddress returnAddress, MacroAssemblerCodePtr newCalleeFunction)
 {
-    returnAddress.relinkNearCallerToTrampoline(newCalleeFunction);
+    MacroAssembler::RepatchBuffer repatchBuffer;
+    repatchBuffer.relinkNearCallerToTrampoline(returnAddress, newCalleeFunction);
 }
 
 void ctiPatchCallByReturnAddress(MacroAssembler::ProcessorReturnAddress returnAddress, MacroAssemblerCodePtr newCalleeFunction)
 {
-    returnAddress.relinkCallerToTrampoline(newCalleeFunction);
+    MacroAssembler::RepatchBuffer repatchBuffer;
+    repatchBuffer.relinkCallerToTrampoline(returnAddress, newCalleeFunction);
 }
 
 void ctiPatchCallByReturnAddress(MacroAssembler::ProcessorReturnAddress returnAddress, FunctionPtr newCalleeFunction)
 {
-    returnAddress.relinkCallerToFunction(newCalleeFunction);
+    MacroAssembler::RepatchBuffer repatchBuffer;
+    repatchBuffer.relinkCallerToFunction(returnAddress, newCalleeFunction);
 }
 
@@ -903 +906 @@
     // (and, if a new JSFunction happened to be constructed at the same location, we could get a false positive
     // match).  Reset the check so it no longer matches.
-    callLinkInfo->hotPathBegin.repatch(JSValue::encode(JSValue()));
+    RepatchBuffer repatchBuffer;
+    repatchBuffer.repatch(callLinkInfo->hotPathBegin, JSValue::encode(JSValue()));
 }
 
 void JIT::linkCall(JSFunction* callee, CodeBlock* calleeCodeBlock, JITCode& code, CallLinkInfo* callLinkInfo, int callerArgCount, JSGlobalData* globalData)
 {
+    RepatchBuffer repatchBuffer;
+
     // Currently we only link calls with the exact number of arguments.
     // If this is a native call calleeCodeBlock is null so the number of parameters is unimportant
@@ -916 +922 @@
             calleeCodeBlock->addCaller(callLinkInfo);
     
-        callLinkInfo->hotPathBegin.repatch(callee);
-        callLinkInfo->hotPathOther.relink(code.addressForCall());
+        repatchBuffer.repatch(callLinkInfo->hotPathBegin, callee);
+        repatchBuffer.relink(callLinkInfo->hotPathOther, code.addressForCall());
     }
 
     // patch the call so we do not continue to try to link.
-    callLinkInfo->callReturnLocation.relink(globalData->jitStubs.ctiVirtualCall());
+    repatchBuffer.relink(callLinkInfo->callReturnLocation, globalData->jitStubs.ctiVirtualCall());
 }