HLSL: Correct which things flattening tracks for linkage, based on caller, not type.

Test/baseResults/hlsl.flattenOpaque.frag.out

@@ -81,6 +81,9 @@ gl_FragCoord origin is upper left
 0:35        Function Call: @main( ( temp 4-component vector of float)
 0:?   Linker Objects
 0:?     'tex' ( uniform texture2D)
+0:?     's2D' ( uniform sampler)
+0:?     's2D' ( uniform sampler)
+0:?     'tex' ( uniform texture2D)
 0:?     '@entryPointOutput' (layout( location=0) out 4-component vector of float)
 
 
@@ -169,6 +172,9 @@ gl_FragCoord origin is upper left
 0:35        Function Call: @main( ( temp 4-component vector of float)
 0:?   Linker Objects
 0:?     'tex' ( uniform texture2D)
+0:?     's2D' ( uniform sampler)
+0:?     's2D' ( uniform sampler)
+0:?     'tex' ( uniform texture2D)
 0:?     '@entryPointOutput' (layout( location=0) out 4-component vector of float)
 
 // Module Version 10000

Test/baseResults/hlsl.structin.vert.out

@@ -155,8 +155,6 @@ Shader version: 500
 0:?     'd' (layout( location=0) in 4-component vector of float)
 0:?     'm[0]' (layout( location=1) in 4-component vector of float)
 0:?     'm[1]' (layout( location=2) in 4-component vector of float)
-0:?     'm[0]' (layout( location=1) in 4-component vector of float)
-0:?     'm[1]' (layout( location=2) in 4-component vector of float)
 0:?     'coord' (layout( location=3) in 4-component vector of float)
 0:?     'b' (layout( location=4) in 4-component vector of float)
 0:?     'e' (layout( location=5) in 4-component vector of float)
@@ -321,8 +319,6 @@ Shader version: 500
 0:?     'd' (layout( location=0) in 4-component vector of float)
 0:?     'm[0]' (layout( location=1) in 4-component vector of float)
 0:?     'm[1]' (layout( location=2) in 4-component vector of float)
-0:?     'm[0]' (layout( location=1) in 4-component vector of float)
-0:?     'm[1]' (layout( location=2) in 4-component vector of float)
 0:?     'coord' (layout( location=3) in 4-component vector of float)
 0:?     'b' (layout( location=4) in 4-component vector of float)
 0:?     'e' (layout( location=5) in 4-component vector of float)

hlsl/hlslParseHelper.h

@@ -133,7 +133,6 @@ public:
     void mergeQualifiers(TQualifier& dst, const TQualifier& src);
     int computeSamplerTypeIndex(TSampler&);
     TSymbol* redeclareBuiltinVariable(const TSourceLoc&, const TString&, const TQualifier&, const TShaderQualifiers&);
-    void redeclareBuiltinBlock(const TSourceLoc&, TTypeList& typeList, const TString& blockName, const TString* instanceName, TArraySizes* arraySizes);
     void paramFix(TType& type);
     void specializationCheck(const TSourceLoc&, const TType&, const char* op);
 
@@ -256,19 +255,17 @@ protected:
     TType& split(TType& type, TString name, const TType* outerStructType = nullptr);
     void split(const TVariable&);
     bool wasSplit(const TIntermTyped* node) const;
-    bool wasSplit(int id) const { return splitIoVars.find(id) != splitIoVars.end(); }
-    TVariable* getSplitIoVar(const TIntermTyped* node) const;
-    TVariable* getSplitIoVar(const TVariable* var) const;
-    TVariable* getSplitIoVar(int id) const;
+    bool wasSplit(int id) const { return splitNonIoVars.find(id) != splitNonIoVars.end(); }
+    TVariable* getSplitNonIoVar(int id) const;
     void addPatchConstantInvocation();
     TIntermTyped* makeIntegerIndex(TIntermTyped*);
 
     void fixBuiltInIoType(TType&);
 
-    void flatten(const TVariable& variable);
-    int flatten(const TVariable& variable, const TType&, TFlattenData&, TString name);
-    int flattenStruct(const TVariable& variable, const TType&, TFlattenData&, TString name);
-    int flattenArray(const TVariable& variable, const TType&, TFlattenData&, TString name);
+    void flatten(const TVariable& variable, bool linkage);
+    int flatten(const TVariable& variable, const TType&, TFlattenData&, TString name, bool linkage);
+    int flattenStruct(const TVariable& variable, const TType&, TFlattenData&, TString name, bool linkage);
+    int flattenArray(const TVariable& variable, const TType&, TFlattenData&, TString name, bool linkage);
 
     bool hasUniform(const TQualifier& qualifier) const;
     void clearUniform(TQualifier& qualifier);
@@ -382,7 +379,7 @@ protected:
     TMap<const TTypeList*, tIoKinds> ioTypeMap;
 
     // Structure splitting data:
-    TMap<int, TVariable*> splitIoVars;  // variables with the built-in interstage IO removed, indexed by unique ID.
+    TMap<int, TVariable*> splitNonIoVars;  // variables with the built-in interstage IO removed, indexed by unique ID.
 
     // Structuredbuffer shared types.  Typically there are only a few.
     TVector<TType*> structBufferTypes;