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

[Nathan Gauër via llvm-commits]

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@@ -3305,6 +3395,24 @@ bool SPIRVInstructionSelector::selectSpvThreadId(Register ResVReg,
   return MIB.constrainAllUses(TII, TRI, RBI);
 }
 
+SPIRVType *
+SPIRVInstructionSelector::getCorrespondingVec4Type(const SPIRVType *Type,
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Keenuts wrote:

nit: name feels a bit weird, as if I could pass a `vec2<T>` and get a `vec4<vec2<T>>`
What about `splatToVec4` or `expantAsVec4` or `widenAsVec4`? Or something closer to SPIR-V naming: `composeVec4From`?

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