[Merge chakra-core/ChakraCore@ffe59396b0] [MERGE #3917 @agarwal-sandeep…

…] 17-10 Security Update that addresses the following issues in ChakraCore Merge pull request #3917 from agarwal-sandeep:1710Fixes CVE-2017-11792, CVE-2017-11796, CVE-2017-11797, CVE-2017-11799, CVE-2017-11801, CVE-2017-11802, CVE-2017-11805, CVE-2017-11806, CVE-2017-11807, CVE-2017-11808, CVE-2017-11809, CVE-2017-11811, CVE-2017-11812, CVE-2017-11821
nodejs · Jan 9, 2018 · 7b2ce30 · 7b2ce30
1 parent 53ddf53
commit 7b2ce30
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Showing 47 changed files with 505 additions and 131 deletions.
diff --git a/deps/chakrashim/core/Build/NuGet/.pack-version b/deps/chakrashim/core/Build/NuGet/.pack-version
@@ -1 +1 @@
-1.7.2
+1.7.3
diff --git a/deps/chakrashim/core/lib/Backend/GlobOpt.cpp b/deps/chakrashim/core/lib/Backend/GlobOpt.cpp
@@ -17122,7 +17122,7 @@ GlobOpt::IsSwitchOptEnabled(Func const * func)
 {
     Assert(func->IsTopFunc());
     return !PHASE_OFF(Js::SwitchOptPhase, func) && !func->IsSwitchOptDisabled() && !IsTypeSpecPhaseOff(func)
-        && func->DoGlobOpt() && !func->HasTry();
+        && DoAggressiveIntTypeSpec(func) && func->DoGlobOpt() && !func->HasTry();
 }
 
 bool

diff --git a/deps/chakrashim/core/lib/Backend/IRBuilderAsmJs.cpp b/deps/chakrashim/core/lib/Backend/IRBuilderAsmJs.cpp
@@ -1027,6 +1027,11 @@ IRBuilderAsmJs::BuildEmpty(Js::OpCodeAsmJs newOpcode, uint32 offset)
     Js::RegSlot retSlot;
     switch (newOpcode)
     {
+    case Js::OpCodeAsmJs::CheckHeap:
+        instr = IR::Instr::New(Js::OpCode::ArrayDetachedCheck, m_func);
+        instr->SetSrc1(IR::IndirOpnd::New(BuildSrcOpnd(AsmJsRegSlots::ArrayReg, TyVar), Js::ArrayBuffer::GetIsDetachedOffset(), TyInt8, m_func));
+        AddInstr(instr, offset);
+        break;
     case Js::OpCodeAsmJs::Unreachable_Void:
         instr = IR::Instr::New(Js::OpCode::ThrowRuntimeError, m_func);
         instr->SetSrc1(IR::IntConstOpnd::New(SCODE_CODE(WASMERR_Unreachable), TyInt32, instr->m_func));
@@ -1775,23 +1780,13 @@ IRBuilderAsmJs::BuildAsmCall(Js::OpCodeAsmJs newOpcode, uint32 offset, Js::ArgSl
     {
         m_func->m_argSlotsForFunctionsCalled = argCount;
     }
-    if (m_asmFuncInfo->UsesHeapBuffer())
-    {
-        // heap buffer can change for wasm
 #ifdef ENABLE_WASM
-        if (m_func->GetJITFunctionBody()->IsWasmFunction())
-        {
-            BuildHeapBufferReload(offset);
-        }
-#endif
-        // after foreign function call, we need to make sure that the heap hasn't been detached
-        if (newOpcode == Js::OpCodeAsmJs::Call)
-        {
-            IR::Instr * instrArrayDetachedCheck = IR::Instr::New(Js::OpCode::ArrayDetachedCheck, m_func);
-            instrArrayDetachedCheck->SetSrc1(IR::IndirOpnd::New(BuildSrcOpnd(AsmJsRegSlots::ArrayReg, TyVar), Js::ArrayBuffer::GetIsDetachedOffset(), TyInt8, m_func));
-            AddInstr(instrArrayDetachedCheck, offset);
-        }
+    // heap buffer can change for wasm
+    if (m_asmFuncInfo->UsesHeapBuffer() && m_func->GetJITFunctionBody()->IsWasmFunction())
+    {
+        BuildHeapBufferReload(offset);
     }
+#endif
 }
 
 void

diff --git a/deps/chakrashim/core/lib/Backend/Lower.cpp b/deps/chakrashim/core/lib/Backend/Lower.cpp
@@ -13373,6 +13373,14 @@ Lowerer::GenerateBailOut(IR::Instr * instr, IR::BranchInstr * branchInstr, IR::L
         // src1 on BailOnNotStackArgs is helping CSE
         instr->FreeSrc1();
     }
+
+    if (instr->GetSrc2() != nullptr)
+    {
+        // Ideally we should never be in this situation but incase we reached a
+        // condition where we didn't freed src2. Free it here.
+        instr->FreeSrc2();
+    }
+
     // Call the bail out wrapper
     instr->m_opcode = Js::OpCode::Call;
     if(instr->GetDst())
@@ -23366,7 +23374,7 @@ Lowerer::GenerateRecyclerAlloc(IR::JnHelperMethod allocHelper, size_t allocSize,
 }
 
 void
-Lowerer::GenerateMemInit(IR::RegOpnd * opnd, int32 offset, int value, IR::Instr * insertBeforeInstr, bool isZeroed)
+Lowerer::GenerateMemInit(IR::RegOpnd * opnd, int32 offset, int32 value, IR::Instr * insertBeforeInstr, bool isZeroed)
 {
     IRType type = TyInt32;
     if (isZeroed)
@@ -24191,7 +24199,7 @@ Lowerer::LowerNewScopeSlots(IR::Instr * instr, bool doStackSlots)
     IR::RegOpnd * dst = instr->UnlinkDst()->AsRegOpnd();
 
     // dst = RecyclerAlloc(allocSize)
-    // dst[EncodedSlotCountSlotIndex = EncodedSlotCountSlotIOndex];
+    // dst[EncodedSlotCountSlotIndex] = min(actualSlotCount, MaxEncodedSlotCount);
     // dst[ScopeMetadataSlotIndex] = FunctionBody;
     // mov undefinedOpnd, undefined
     // dst[FirstSlotIndex..count] = undefinedOpnd;
@@ -24202,8 +24210,10 @@ Lowerer::LowerNewScopeSlots(IR::Instr * instr, bool doStackSlots)
     {
         GenerateRecyclerAlloc(IR::HelperAllocMemForVarArray, allocSize, dst, instr);
     }
-    GenerateMemInit(dst, Js::ScopeSlots::EncodedSlotCountSlotIndex * sizeof(Js::Var),
-        min<uint>(actualSlotCount, Js::ScopeSlots::MaxEncodedSlotCount), instr, !doStackSlots);
+
+    m_lowererMD.GenerateMemInit(dst, Js::ScopeSlots::EncodedSlotCountSlotIndex * sizeof(Js::Var),
+            (size_t)min<uint>(actualSlotCount, Js::ScopeSlots::MaxEncodedSlotCount), instr, !doStackSlots);
+
     IR::Opnd * functionInfoOpnd = this->LoadFunctionInfoOpnd(instr);
     GenerateMemInit(dst, Js::ScopeSlots::ScopeMetadataSlotIndex * sizeof(Js::Var),
         functionInfoOpnd, instr, !doStackSlots);
@@ -25143,7 +25153,7 @@ Lowerer::LowerFrameDisplayCheck(IR::Instr * instr)
 
                 indirOpnd = IR::IndirOpnd::New(slotArrayOpnd,
                                                Js::ScopeSlots::EncodedSlotCountSlotIndex * sizeof(Js::Var),
-                                               TyUint32, m_func, true);
+                                               TyVar, m_func, true);
                 IR::IntConstOpnd * slotIdOpnd = IR::IntConstOpnd::New(slotId - Js::ScopeSlots::FirstSlotIndex,
                                                                       TyUint32, m_func);
                 InsertCompareBranch(indirOpnd, slotIdOpnd, Js::OpCode::BrLe_A, true, errorLabel, insertInstr);
@@ -25198,7 +25208,7 @@ Lowerer::LowerSlotArrayCheck(IR::Instr * instr)
 
         IR::IndirOpnd * indirOpnd = IR::IndirOpnd::New(IR::RegOpnd::New(stackSym, TyVar, m_func),
                                                        Js::ScopeSlots::EncodedSlotCountSlotIndex * sizeof(Js::Var),
-                                                       TyUint32, m_func, true);
+                                                       TyVar, m_func, true);
 
         slotIdOpnd->SetValue(slotId - Js::ScopeSlots::FirstSlotIndex);
         InsertCompareBranch(indirOpnd, slotIdOpnd, Js::OpCode::BrGt_A, true, continueLabel, insertInstr);

diff --git a/deps/chakrashim/core/lib/Backend/LowerMDShared.cpp b/deps/chakrashim/core/lib/Backend/LowerMDShared.cpp
@@ -62,6 +62,16 @@ LowererMD::GenerateMemRef(intptr_t addr, IRType type, IR::Instr *instr, bool don
     return IR::MemRefOpnd::New(addr, type, this->m_func);
 }
 
+void
+LowererMD::GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed)
+{
+#if _M_X64
+    lowererMDArch.GenerateMemInit(opnd, offset, value, insertBeforeInstr, isZeroed);
+#else
+    m_lowerer->GenerateMemInit(opnd, offset, (uint32)value, insertBeforeInstr, isZeroed);
+#endif
+}
+
 ///----------------------------------------------------------------------------
 ///
 /// LowererMD::InvertBranch

diff --git a/deps/chakrashim/core/lib/Backend/LowerMDShared.h b/deps/chakrashim/core/lib/Backend/LowerMDShared.h
@@ -72,6 +72,7 @@ class LowererMD
 public:
             void            Init(Lowerer *lowerer);
             IR::Opnd *      GenerateMemRef(intptr_t addr, IRType type, IR::Instr *instr, bool dontEncode = false);
+            void            GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed = false);
             IR::Instr *     ChangeToHelperCall(IR::Instr * instr, IR::JnHelperMethod helperMethod, IR::LabelInstr *labelBailOut = nullptr,
                                                IR::Opnd *opndInstance = nullptr, IR::PropertySymOpnd * propSymOpnd = nullptr, bool isHelperContinuation = false);
             void            FinalLower();

diff --git a/deps/chakrashim/core/lib/Backend/amd64/LowererMDArch.cpp b/deps/chakrashim/core/lib/Backend/amd64/LowererMDArch.cpp
@@ -577,6 +577,28 @@ LowererMDArch::SetMaxArgSlots(Js::ArgSlot actualCount /*including this*/)
     return;
 }
 
+void
+LowererMDArch::GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed)
+{
+    IRType type = TyVar;
+    if (isZeroed)
+    {
+        if (value == 0)
+        {
+            // Recycler memory are zero initialized
+            return;
+        }
+
+        type = value <= UINT_MAX ?
+            (value <= USHORT_MAX ?
+            (value <= UCHAR_MAX ? TyUint8 : TyUint16) :
+                TyUint32) :
+            type;
+    }
+    Func * func = this->m_func;
+    lowererMD->GetLowerer()->InsertMove(IR::IndirOpnd::New(opnd, offset, type, func), IR::IntConstOpnd::New(value, type, func), insertBeforeInstr);
+}
+
 IR::Instr *
 LowererMDArch::LowerCallIDynamic(IR::Instr *callInstr, IR::Instr*saveThisArgOutInstr, IR::Opnd *argsLength, ushort callFlags, IR::Instr * insertBeforeInstrForCFG)
 {

diff --git a/deps/chakrashim/core/lib/Backend/amd64/LowererMDArch.h b/deps/chakrashim/core/lib/Backend/amd64/LowererMDArch.h
@@ -158,6 +158,7 @@ class LowererMDArch
     IR::LabelInstr *    GetBailOutStackRestoreLabel(BailOutInfo * bailOutInfo, IR::LabelInstr * exitTargetInstr);
     void                GeneratePreCall(IR::Instr * callInstr, IR::Opnd  *functionObjOpnd, IR::Instr* insertBeforeInstrForCFGCheck = nullptr);
     void                SetMaxArgSlots(Js::ArgSlot actualCount /*including this*/);
+    void                GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed = false);
 };
 
 #define REG_EH_TARGET      RegArg0

diff --git a/deps/chakrashim/core/lib/Backend/arm/LowerMD.cpp b/deps/chakrashim/core/lib/Backend/arm/LowerMD.cpp
@@ -378,6 +378,12 @@ LowererMD::SetMaxArgSlots(Js::ArgSlot actualCount /*including this*/)
     return;
 }
 
+void
+LowererMD::GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed)
+{
+    m_lowerer->GenerateMemInit(opnd, offset, (uint32)value, insertBeforeInstr, isZeroed);
+}
+
 IR::Instr *
 LowererMD::LowerCallIDynamic(IR::Instr *callInstr, IR::Instr*saveThisArgOutInstr, IR::Opnd *argsLength, ushort callFlags, IR::Instr * insertBeforeInstrForCFG)
 {

diff --git a/deps/chakrashim/core/lib/Backend/arm/LowerMD.h b/deps/chakrashim/core/lib/Backend/arm/LowerMD.h
@@ -275,6 +275,7 @@ class LowererMD
 
             void                LowerInlineSpreadArgOutLoop(IR::Instr *callInstr, IR::RegOpnd *indexOpnd, IR::RegOpnd *arrayElementsStartOpnd);
             void                LowerTypeof(IR::Instr * typeOfInstr);
+            void                GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed = false);
 
 public:
     static IR::Instr * InsertCmovCC(const Js::OpCode opCode, IR::Opnd * dst, IR::Opnd* src1, IR::Instr* insertBeforeInstr, bool postRegAlloc);

diff --git a/deps/chakrashim/core/lib/Backend/arm64/LowerMD.h b/deps/chakrashim/core/lib/Backend/arm64/LowerMD.h
@@ -268,6 +268,7 @@ class LowererMD
 
               void                LowerInlineSpreadArgOutLoop(IR::Instr *callInstr, IR::RegOpnd *indexOpnd, IR::RegOpnd *arrayElementsStartOpnd) { __debugbreak(); }
               void                LowerTypeof(IR::Instr * typeOfInstr) { __debugbreak(); }
+              void                GenerateMemInit(IR::RegOpnd * opnd, int32 offset, size_t value, IR::Instr * insertBeforeInstr, bool isZeroed = false) { __debugbreak(); }
 public:
     static IR::Instr * InsertCmovCC(const Js::OpCode opCode, IR::Opnd * dst, IR::Opnd* src1, IR::Instr* insertBeforeInstr, bool postRegAlloc) { __debugbreak(); }
 };
diff --git a/deps/chakrashim/core/lib/Common/ChakraCoreVersion.h b/deps/chakrashim/core/lib/Common/ChakraCoreVersion.h
@@ -17,7 +17,7 @@
 // ChakraCore version number definitions (used in ChakraCore binary metadata)
 #define CHAKRA_CORE_MAJOR_VERSION 1
 #define CHAKRA_CORE_MINOR_VERSION 7
-#define CHAKRA_CORE_PATCH_VERSION 2
+#define CHAKRA_CORE_PATCH_VERSION 3
 #define CHAKRA_CORE_VERSION_RELEASE_QFE 0 // Redundant with PATCH_VERSION. Keep this value set to 0.
 
 // -------------

diff --git a/deps/chakrashim/core/lib/Common/ConfigFlagsList.h b/deps/chakrashim/core/lib/Common/ConfigFlagsList.h
@@ -1057,6 +1057,9 @@ FLAGPR_REGOVR_EXP(Boolean, ES6, ES6RegExPrototypeProperties, "Enable ES6 propert
 #ifndef COMPILE_DISABLE_ES6RegExSymbols
     #define COMPILE_DISABLE_ES6RegExSymbols 0
 #endif
+
+// When we enable ES6RegExSymbols check all String and Regex built-ins which are inlined in JIT and make sure the helper
+// sets implicit call flag before calling into script
 FLAGPR_REGOVR_EXP(Boolean, ES6, ES6RegExSymbols        , "Enable ES6 RegExp symbols"                                , DEFAULT_CONFIG_ES6RegExSymbols)
 
 FLAGPR           (Boolean, ES6, ES6HasInstance         , "Enable ES6 @@hasInstance symbol"                          , DEFAULT_CONFIG_ES6HasInstance)

diff --git a/deps/chakrashim/core/lib/JITClient/JITManager.cpp b/deps/chakrashim/core/lib/JITClient/JITManager.cpp
@@ -13,7 +13,7 @@ void * __RPC_USER midl_user_allocate(
 #endif
     size_t size)
 {
-    return (HeapAlloc(GetProcessHeap(), 0, size));
+    return (HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, size));
 }
 
 void __RPC_USER midl_user_free(_Pre_maybenull_ _Post_invalid_ void * ptr)

diff --git a/deps/chakrashim/core/lib/Parser/Parse.cpp b/deps/chakrashim/core/lib/Parser/Parse.cpp
@@ -90,6 +90,8 @@ Parser::Parser(Js::ScriptContext* scriptContext, BOOL strictMode, PageAllocator
     m_stoppedDeferredParse = FALSE;
     m_hasParallelJob = false;
     m_doingFastScan = false;
+    m_isInParsingArgList = false;
+    m_hasDestructuringPattern = false;
     m_scriptContext = scriptContext;
     m_pCurrentAstSize = nullptr;
     m_arrayDepth = 0;
@@ -1252,7 +1254,7 @@ Parser::CreateCallNode(OpCode nop, ParseNodePtr pnode1, ParseNodePtr pnode2,char
     pnode->sxCall.isApplyCall = false;
     pnode->sxCall.isEvalCall = false;
     pnode->sxCall.isSuperCall = false;
-
+    pnode->sxCall.hasDestructuring = false;
     pnode->ichMin = ichMin;
     pnode->ichLim = ichLim;
 
@@ -3660,6 +3662,7 @@ ParseNodePtr Parser::ParsePostfixOperators(
         {
         case tkLParen:
             {
+                AutoMarkInParsingArgs autoMarkInParsingArgs(this);
                 if (fInNew)
                 {
                     ParseNodePtr pnodeArgs = ParseArgList<buildAST>(&callOfConstants, &spreadArgCount, &count);
@@ -3672,6 +3675,8 @@ ParseNodePtr Parser::ParsePostfixOperators(
                         pnode->sxCall.isApplyCall = false;
                         pnode->sxCall.isEvalCall = false;
                         pnode->sxCall.isSuperCall = false;
+                        pnode->sxCall.hasDestructuring = m_hasDestructuringPattern;
+                        Assert(!m_hasDestructuringPattern || count > 0);
                         pnode->sxCall.argCount = count;
                         pnode->sxCall.spreadArgCount = spreadArgCount;
                         pnode->ichLim = m_pscan->IchLimTok();
@@ -3743,6 +3748,8 @@ ParseNodePtr Parser::ParsePostfixOperators(
                         pnode->sxCall.spreadArgCount = spreadArgCount;
                         pnode->sxCall.isApplyCall = false;
                         pnode->sxCall.isEvalCall = fCallIsEval;
+                        pnode->sxCall.hasDestructuring = m_hasDestructuringPattern;
+                        Assert(!m_hasDestructuringPattern || count > 0);
                         pnode->sxCall.argCount = count;
                         pnode->ichLim = m_pscan->IchLimTok();
                     }
@@ -8630,6 +8637,7 @@ ParseNodePtr Parser::ParseExpr(int oplMin,
 
             if (buildAST)
             {
+                this->SetHasDestructuringPattern(true);
                 pnode = ConvertToPattern(pnode);
             }
 

diff --git a/deps/chakrashim/core/lib/Parser/Parse.h b/deps/chakrashim/core/lib/Parser/Parse.h
@@ -136,6 +136,12 @@ class Parser
     bool IsBackgroundParser() const { return m_isInBackground; }
     bool IsDoingFastScan() const { return m_doingFastScan; }
 
+    bool GetIsInParsingArgList() const { return m_isInParsingArgList; }
+    void SetIsInParsingArgList(bool set) { m_isInParsingArgList = set; }
+
+    bool GetHasDestructuringPattern() const { return m_hasDestructuringPattern; }
+    void SetHasDestructuringPattern(bool set) { m_hasDestructuringPattern = set; }
+
     static IdentPtr PidFromNode(ParseNodePtr pnode);
 
     ParseNode* CopyPnode(ParseNode* pnode);
@@ -395,7 +401,8 @@ class Parser
     bool m_isInBackground;
     bool m_reparsingLambdaParams;
     bool m_disallowImportExportStmt;
-
+    bool m_isInParsingArgList;
+    bool m_hasDestructuringPattern;
     // This bool is used for deferring the shorthand initializer error ( {x = 1}) - as it is allowed in the destructuring grammar.
     bool m_hasDeferredShorthandInitError;
     uint * m_pnestedCount; // count of functions nested at one level below the current node
@@ -1110,6 +1117,30 @@ class Parser
         }
     };
 
+    class AutoMarkInParsingArgs
+    {
+    public:
+        AutoMarkInParsingArgs(Parser * parser)
+            : m_parser(parser)
+        {
+            m_prevState = m_parser->GetIsInParsingArgList();
+            m_parser->SetHasDestructuringPattern(false);
+            m_parser->SetIsInParsingArgList(true);
+        }
+        ~AutoMarkInParsingArgs()
+        {
+            m_parser->SetIsInParsingArgList(m_prevState);
+            if (!m_prevState)
+            {
+                m_parser->SetHasDestructuringPattern(false);
+            }
+        }
+
+    private:
+        Parser *m_parser;
+        bool m_prevState;
+    };
+
 public:
     charcount_t GetSourceIchLim() { return m_sourceLim; }
     static BOOL NodeEqualsName(ParseNodePtr pnode, LPCOLESTR sz, uint32 cch);

diff --git a/deps/chakrashim/core/lib/Parser/ptree.h b/deps/chakrashim/core/lib/Parser/ptree.h
@@ -459,6 +459,7 @@ struct PnCall
     BYTE isApplyCall : 1;
     BYTE isEvalCall : 1;
     BYTE isSuperCall : 1;
+    BYTE hasDestructuring : 1;
 };
 
 struct PnStmt

diff --git a/deps/chakrashim/core/lib/Runtime/Base/CrossSite.cpp b/deps/chakrashim/core/lib/Runtime/Base/CrossSite.cpp
@@ -438,6 +438,10 @@ namespace Js
     Var CrossSite::CommonThunk(RecyclableObject* recyclableObject, JavascriptMethod entryPoint, Arguments args)
     {
         DynamicObject* function = DynamicObject::FromVar(recyclableObject);
+
+        FunctionInfo * functionInfo = (JavascriptFunction::Is(function) ? JavascriptFunction::FromVar(function)->GetFunctionInfo() : nullptr);
+        AutoDisableRedeferral autoDisableRedeferral(functionInfo);
+
         ScriptContext* targetScriptContext = function->GetScriptContext();
         Assert(!targetScriptContext->IsClosed());
         Assert(function->IsExternal() || function->IsCrossSiteObject());

diff --git a/deps/chakrashim/core/lib/Runtime/Base/FunctionBody.cpp b/deps/chakrashim/core/lib/Runtime/Base/FunctionBody.cpp
@@ -1912,8 +1912,9 @@ namespace Js
     {
         Assert(pnodeFnc->nop == knopFncDecl);
 
-        Recycler *recycler = GetScriptContext()->GetRecycler();
-        this->SetDeferredStubs(BuildDeferredStubTree(pnodeFnc, recycler));
+        // TODO: Disabling the creation of deferred stubs for now. We need to rethink the design again as the current behavior
+        // is not usable with precise capturing.
+        this->SetDeferredStubs(nullptr);
     }
 
     FunctionInfoArray ParseableFunctionInfo::GetNestedFuncArray()

diff --git a/deps/chakrashim/core/lib/Runtime/Base/FunctionBody.h b/deps/chakrashim/core/lib/Runtime/Base/FunctionBody.h
@@ -3792,9 +3792,9 @@ namespace Js
             slotArray[ScopeMetadataSlotIndex] = scopeMetadataObj;
         }
 
-        uint GetCount() const
+        size_t GetCount() const
         {
-            return ::Math::PointerCastToIntegralTruncate<uint>(slotArray[EncodedSlotCountSlotIndex]);
+            return ::Math::PointerCastToIntegralTruncate<size_t>(slotArray[EncodedSlotCountSlotIndex]);
         }
 
         void SetCount(uint count)