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

[Nathan Gauër via llvm-commits]

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@@ -83,6 +83,14 @@ SPIRVSubtarget::SPIRVSubtarget(const Triple &TT, const std::string &CPU,
   }
   OpenCLVersion = VersionTuple(2, 2);
 
+  // Set the environment based on the target triple.
+  if (TargetTriple.getOS() == Triple::Vulkan)
+    Env = Shader;
+  else if (TargetTriple.getEnvironment() == Triple::OpenCL)
+    Env = Kernel;
+  else
+    Env = Unknown;
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Keenuts wrote:

Since most of the code is `if Kerne/Shader else`, then I'd say leaving unknown as a selected value would be very uncertain.
I'd also be in favor of a louder error, like an `report_fatal_error`

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