Imported QtWebKit TP3 (git b57bc6801f1876c3220d5a4bfea33d620d477443)

Change-Id: I3b1d8a2808782c9f34d50240000e20cb38d3680f
Reviewed-by: Konstantin Tokarev <annulen@yandex.ru>

1 files changed, 141 insertions, 67 deletions

diff --git a/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp b/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp
index 70cf2fccb..5ffd743a6 100644
--- a/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp
+++ b/Source/JavaScriptCore/bytecode/StructureStubInfo.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2008 Apple Inc. All rights reserved.
+ * Copyright (C) 2008, 2014, 2015 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,97 +26,171 @@
 #include "config.h"
 #include "StructureStubInfo.h"
 
+#include "JSCellInlines.h"
 #include "JSObject.h"
-#include "PolymorphicPutByIdList.h"
-
+#include "PolymorphicAccess.h"
+#include "Repatch.h"
 
 namespace JSC {
 
 #if ENABLE(JIT)
+StructureStubInfo::StructureStubInfo(AccessType accessType)
+    : callSiteIndex(UINT_MAX)
+    , accessType(accessType)
+    , cacheType(CacheType::Unset)
+    , countdown(1) // For a totally clear stub, we'll patch it after the first execution.
+    , repatchCount(0)
+    , numberOfCoolDowns(0)
+    , resetByGC(false)
+    , tookSlowPath(false)
+    , everConsidered(false)
+{
+}
+
+StructureStubInfo::~StructureStubInfo()
+{
+}
+
+void StructureStubInfo::initGetByIdSelf(CodeBlock* codeBlock, Structure* baseObjectStructure, PropertyOffset offset)
+{
+    cacheType = CacheType::GetByIdSelf;
+    
+    u.byIdSelf.baseObjectStructure.set(
+        *codeBlock->vm(), codeBlock, baseObjectStructure);
+    u.byIdSelf.offset = offset;
+}
+
+void StructureStubInfo::initPutByIdReplace(CodeBlock* codeBlock, Structure* baseObjectStructure, PropertyOffset offset)
+{
+    cacheType = CacheType::PutByIdReplace;
+    
+    u.byIdSelf.baseObjectStructure.set(
+        *codeBlock->vm(), codeBlock, baseObjectStructure);
+    u.byIdSelf.offset = offset;
+}
+
+void StructureStubInfo::initStub(CodeBlock*, std::unique_ptr<PolymorphicAccess> stub)
+{
+    cacheType = CacheType::Stub;
+    u.stub = stub.release();
+}
+
 void StructureStubInfo::deref()
 {
-    switch (accessType) {
-    case access_get_by_id_self_list: {
-        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdSelfList.structureList;
-        delete polymorphicStructures;
+    switch (cacheType) {
+    case CacheType::Stub:
+        delete u.stub;
         return;
-    }
-    case access_get_by_id_proto_list: {
-        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdProtoList.structureList;
-        delete polymorphicStructures;
+    case CacheType::Unset:
+    case CacheType::GetByIdSelf:
+    case CacheType::PutByIdReplace:
         return;
     }
-    case access_put_by_id_list:
-        delete u.putByIdList.list;
+
+    RELEASE_ASSERT_NOT_REACHED();
+}
+
+void StructureStubInfo::aboutToDie()
+{
+    switch (cacheType) {
+    case CacheType::Stub:
+        u.stub->aboutToDie();
         return;
-    case access_get_by_id_self:
-    case access_get_by_id_proto:
-    case access_get_by_id_chain:
-    case access_put_by_id_transition_normal:
-    case access_put_by_id_transition_direct:
-    case access_put_by_id_replace:
-    case access_unset:
-    case access_get_by_id_generic:
-    case access_put_by_id_generic:
-    case access_get_array_length:
-    case access_get_string_length:
-        // These instructions don't have to release any allocated memory
+    case CacheType::Unset:
+    case CacheType::GetByIdSelf:
+    case CacheType::PutByIdReplace:
         return;
-    default:
-        RELEASE_ASSERT_NOT_REACHED();
     }
+
+    RELEASE_ASSERT_NOT_REACHED();
 }
 
-bool StructureStubInfo::visitWeakReferences()
+MacroAssemblerCodePtr StructureStubInfo::addAccessCase(
+    CodeBlock* codeBlock, const Identifier& ident, std::unique_ptr<AccessCase> accessCase)
 {
+    VM& vm = *codeBlock->vm();
+    
+    if (!accessCase)
+        return MacroAssemblerCodePtr();
+    
+    if (cacheType == CacheType::Stub)
+        return u.stub->regenerateWithCase(vm, codeBlock, *this, ident, WTFMove(accessCase));
+
+    std::unique_ptr<PolymorphicAccess> access = std::make_unique<PolymorphicAccess>();
+    
+    Vector<std::unique_ptr<AccessCase>> accessCases;
+    
+    std::unique_ptr<AccessCase> previousCase =
+        AccessCase::fromStructureStubInfo(vm, codeBlock, *this);
+    if (previousCase)
+        accessCases.append(WTFMove(previousCase));
+
+    accessCases.append(WTFMove(accessCase));
+
+    MacroAssemblerCodePtr result =
+        access->regenerateWithCases(vm, codeBlock, *this, ident, WTFMove(accessCases));
+
+    if (!result)
+        return MacroAssemblerCodePtr();
+
+    initStub(codeBlock, WTFMove(access));
+    return result;
+}
+
+void StructureStubInfo::reset(CodeBlock* codeBlock)
+{
+    if (cacheType == CacheType::Unset)
+        return;
+    
+    if (Options::verboseOSR()) {
+        // This can be called from GC destructor calls, so we don't try to do a full dump
+        // of the CodeBlock.
+        dataLog("Clearing structure cache (kind ", static_cast<int>(accessType), ") in ", RawPointer(codeBlock), ".\n");
+    }
+
     switch (accessType) {
-    case access_get_by_id_self:
-        if (!Heap::isMarked(u.getByIdSelf.baseObjectStructure.get()))
-            return false;
-        break;
-    case access_get_by_id_proto:
-        if (!Heap::isMarked(u.getByIdProto.baseObjectStructure.get())
-            || !Heap::isMarked(u.getByIdProto.prototypeStructure.get()))
-            return false;
-        break;
-    case access_get_by_id_chain:
-        if (!Heap::isMarked(u.getByIdChain.baseObjectStructure.get())
-            || !Heap::isMarked(u.getByIdChain.chain.get()))
-            return false;
+    case AccessType::Get:
+        resetGetByID(codeBlock, *this);
         break;
-    case access_get_by_id_self_list: {
-        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdSelfList.structureList;
-        if (!polymorphicStructures->visitWeak(u.getByIdSelfList.listSize))
-            return false;
+    case AccessType::Put:
+        resetPutByID(codeBlock, *this);
         break;
-    }
-    case access_get_by_id_proto_list: {
-        PolymorphicAccessStructureList* polymorphicStructures = u.getByIdProtoList.structureList;
-        if (!polymorphicStructures->visitWeak(u.getByIdProtoList.listSize))
-            return false;
+    case AccessType::In:
+        resetIn(codeBlock, *this);
         break;
     }
-    case access_put_by_id_transition_normal:
-    case access_put_by_id_transition_direct:
-        if (!Heap::isMarked(u.putByIdTransition.previousStructure.get())
-            || !Heap::isMarked(u.putByIdTransition.structure.get())
-            || !Heap::isMarked(u.putByIdTransition.chain.get()))
-            return false;
-        break;
-    case access_put_by_id_replace:
-        if (!Heap::isMarked(u.putByIdReplace.baseObjectStructure.get()))
-            return false;
+    
+    deref();
+    cacheType = CacheType::Unset;
+}
+
+void StructureStubInfo::visitWeakReferences(CodeBlock* codeBlock)
+{
+    VM& vm = *codeBlock->vm();
+
+    switch (cacheType) {
+    case CacheType::GetByIdSelf:
+    case CacheType::PutByIdReplace:
+        if (Heap::isMarked(u.byIdSelf.baseObjectStructure.get()))
+            return;
         break;
-    case access_put_by_id_list:
-        if (!u.putByIdList.list->visitWeak())
-            return false;
+    case CacheType::Stub:
+        if (u.stub->visitWeak(vm))
+            return;
         break;
     default:
-        // The rest of the instructions don't require references, so there is no need to
-        // do anything.
-        break;
+        return;
     }
-    return true;
+
+    reset(codeBlock);
+    resetByGC = true;
+}
+
+bool StructureStubInfo::containsPC(void* pc) const
+{
+    if (cacheType != CacheType::Stub)
+        return false;
+    return u.stub->containsPC(pc);
 }
 #endif