[llvm] [SPIRV] Emit intrinsics for globals only in function that references them (PR #178143)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -62,6 +62,75 @@ namespace llvm::SPIRV {
 } // namespace llvm::SPIRV
 
 namespace {
+// This class keeps track of which functions reference which global variables.
+class GlobalVariableReferences {
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jmmartinez wrote:

Maybe `getFunctionsReferencing()` or something like that.

https://github.com/llvm/llvm-project/pull/178143