[llvm] [SPIRV] Change how to detect OpenCL/Vulkan Env and update tests accordingly. (PR #129689)

[Nathan Gauër via llvm-commits]

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@@ -78,14 +83,22 @@ class SPIRVSubtarget : public SPIRVGenSubtargetInfo {
   unsigned getPointerSize() const { return PointerSize; }
   unsigned getBound() const { return GR->getBound(); }
   bool canDirectlyComparePointers() const;
-  // TODO: this environment is not implemented in Triple, we need to decide
-  // how to standardize its support. For now, let's assume SPIR-V with physical
-  // addressing is OpenCL, and Logical addressing is Vulkan.
-  bool isOpenCLEnv() const {
+  void setEnv(SPIRVEnvType E) {
+    assert(E != Unknown && "Unknown environment is not allowed");
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Keenuts wrote:

I'd also be in favor or an error, like `report_fatal_error` if the env is used when set/used with Unknown: most conditons we have are `if isKernel()/isShader() {} else` or something similar. Meaning the behavior you'd get by having Env set to unknown would inconsistent.

https://github.com/llvm/llvm-project/pull/129689