[llvm] [SPIRV] Add reads from image buffer for shaders. (PR #115178)

[Steven Perron via llvm-commits]

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@@ -388,6 +391,12 @@ class SPIRVGlobalRegistry {
   unsigned getScalarOrVectorComponentCount(Register VReg) const;
   unsigned getScalarOrVectorComponentCount(SPIRVType *Type) const;
 
+  // Return the component type in a vector if the argument is associated with
+  // a vector type. Returns the argument itself for a scalar type, and nullptr
+  // for a missing type.
+  SPIRVType *getScalarOrVectorComponentType(Register VReg) const;
+  SPIRVType *getScalarOrVectorComponentType(SPIRVType *Type) const;
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s-perron wrote:

I updated the comment to say that it returns the type itself for any type other than vector.

This behaviour matches all of the other `scalarOrVector` functions. I've added an assert to make sure that the result of this function matches with `isScalarOrVectorOfType`.

https://github.com/llvm/llvm-project/pull/115178