[clang] [Clang] diagnosing missing Vulkan environment when using SPIR-V triple (PR #190840)

[Aaron Ballman via cfe-commits]

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@@ -341,20 +343,27 @@ class LLVM_LIBRARY_VISIBILITY SPIRVTargetInfo : public BaseSPIRVTargetInfo {
       : BaseSPIRVTargetInfo(Triple, Opts) {
     assert(Triple.getArch() == llvm::Triple::spirv &&
            "Invalid architecture for Logical SPIR-V.");
-    assert(Triple.getOS() == llvm::Triple::Vulkan &&
-           Triple.getVulkanVersion() != llvm::VersionTuple(0) &&
-           "Logical SPIR-V requires a valid Vulkan environment.");
-    assert(Triple.getEnvironment() >= llvm::Triple::Pixel &&
-           Triple.getEnvironment() <= llvm::Triple::Amplification &&
-           "Logical SPIR-V environment must be a valid shader stage.");
     PointerWidth = PointerAlign = 64;
 
     // SPIR-V IDs are represented with a single 32-bit word.
     SizeType = TargetInfo::UnsignedInt;
-    VectorsAreElementAligned = true;
     resetDataLayout();
   }
 
+  // SPIR-V targeting requires a fully specified Vulkan environment.
+  // Validate here before CreateTargetInfo() to emit a proper diagnostic
+  bool validateTarget(DiagnosticsEngine &Diags) const override {
+    if (getTriple().getOS() != llvm::Triple::Vulkan ||
+        getTriple().getVulkanVersion() == llvm::VersionTuple(0)) {
+      Diags.Report(diag::err_fe_spirv_requires_vulkan);
+      return false;
+    }
+    assert(getTriple().getEnvironment() >= llvm::Triple::Pixel &&
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AaronBallman wrote:

This should also be a diagnostic instead of an assertion, similar to what you did for Vulkan, because it has the same bug: https://godbolt.org/z/TsrfhfWT8

You should also add a RUN line to the test case for that; you can use `--check-prefix` on the `FileCheck` line to distinguish between the two RUN lines for checking the diagnostic output, like done here: https://github.com/llvm/llvm-project/blob/46bbbde1f3c3bf3a00ae19c3157f7425899b1e87/clang/test/Frontend/gnu-inline.c#L1

https://github.com/llvm/llvm-project/pull/190840