SPV: Fix #807: use --hlsl-offsets to allow hlsl-style offsets in a buffer.

Corresponds to the EShMsgHlslOffsets flag in messages.
Works for both GLSL and HLSL.

glslang/Include/revision.h

@@ -2,5 +2,5 @@
 // For the version, it uses the latest git tag followed by the number of commits.
 // For the date, it uses the current date (when then script is run).
 
-#define GLSLANG_REVISION "Overload400-PrecQual.1974"
-#define GLSLANG_DATE "04-Apr-2017"
+#define GLSLANG_REVISION "Overload400-PrecQual.1978"
+#define GLSLANG_DATE "05-Apr-2017"

glslang/MachineIndependent/ShaderLang.cpp

@@ -726,6 +726,8 @@ bool ProcessDeferred(
     intermediate.setSpv(spvVersion);
     if (spvVersion.vulkan >= 100)
         intermediate.setOriginUpperLeft();
+    if (messages & EShMsgHlslOffsets) // source-language independent
+        intermediate.setHlslOffsets();
     SetupBuiltinSymbolTable(version, profile, spvVersion, source);
 
     TSymbolTable* cachedTable = SharedSymbolTables[MapVersionToIndex(version)]

glslang/MachineIndependent/linkValidate.cpp

@@ -1047,9 +1047,9 @@ unsigned int TIntermediate::computeTypeXfbSize(const TType& type, bool& contains
 
 const int baseAlignmentVec4Std140 = 16;
 
-// Return the size and alignment of a scalar.
+// Return the size and alignment of a component of the given type.
 // The size is returned in the 'size' parameter
-// Return value is the alignment of the type.
+// Return value is the alignment..
 int TIntermediate::getBaseAlignmentScalar(const TType& type, int& size)
 {
     switch (type.getBasicType()) {
@@ -1219,4 +1219,14 @@ int TIntermediate::getBaseAlignment(const TType& type, int& size, int& stride, b
     return baseAlignmentVec4Std140;
 }
 
+// To aid the basic HLSL rule about crossing vec4 boundaries.
+bool TIntermediate::improperStraddle(const TType& type, int size, int offset)
+{
+    if (! type.isVector() || type.isArray())
+        return false;
+
+    return size <= 16 ? offset / 16 != (offset + size - 1) / 16
+                      : offset % 16 != 0;
+}
+
 } // end namespace glslang

glslang/MachineIndependent/localintermediate.h

@@ -177,7 +177,8 @@ public:
         shiftSsboBinding(0),
         autoMapBindings(false),
         flattenUniformArrays(false),
-        useUnknownFormat(false)
+        useUnknownFormat(false),
+        hlslOffsets(false)
     {
         localSize[0] = 1;
         localSize[1] = 1;
@@ -216,6 +217,8 @@ public:
     bool getFlattenUniformArrays()        const { return flattenUniformArrays; }
     void setNoStorageFormat(bool b)             { useUnknownFormat = b; }
     bool getNoStorageFormat()             const { return useUnknownFormat; }
+    void setHlslOffsets()         { hlslOffsets = true; }
+    bool usingHlslOFfsets() const { return hlslOffsets; }
 
     void setVersion(int v) { version = v; }
     int getVersion() const { return version; }
@@ -413,7 +416,9 @@ public:
     }
     int addXfbBufferOffset(const TType&);
     unsigned int computeTypeXfbSize(const TType&, bool& containsDouble) const;
+    static int getBaseAlignmentScalar(const TType&, int& size);
     static int getBaseAlignment(const TType&, int& size, int& stride, bool std140, bool rowMajor);
+    static bool improperStraddle(const TType& type, int size, int offset);
     bool promote(TIntermOperator*);
 
 #ifdef NV_EXTENSIONS
@@ -443,7 +448,6 @@ protected:
     void inOutLocationCheck(TInfoSink&);
     TIntermSequence& findLinkerObjects() const;
     bool userOutputUsed() const;
-    static int getBaseAlignmentScalar(const TType&, int& size);
     bool isSpecializationOperation(const TIntermOperator&) const;
     bool promoteUnary(TIntermUnary&);
     bool promoteBinary(TIntermBinary&);
@@ -499,6 +503,7 @@ protected:
     bool autoMapBindings;
     bool flattenUniformArrays;
     bool useUnknownFormat;
+    bool hlslOffsets;
 
     typedef std::list<TCall> TGraph;
     TGraph callGraph;

glslang/Public/ShaderLang.h

@@ -147,6 +147,7 @@ enum EShMessages {
     EShMsgReadHlsl         = (1 << 6),  // use HLSL parsing rules and semantics
     EShMsgCascadingErrors  = (1 << 7),  // get cascading errors; risks error-recovery issues, instead of an early exit
     EShMsgKeepUncalled     = (1 << 8),  // for testing, don't eliminate uncalled functions
+    EShMsgHlslOffsets      = (1 << 9),  // allow block offsets to follow HLSL rules instead of GLSL rules
 };
 
 //