[llvm] [SPIR-V] Reject fp128 and ppc_fp128 types with a diagnostic (PR #208397)

[Arseniy Obolenskiy via llvm-commits]

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@@ -1204,6 +1205,12 @@ SPIRVTypeInst SPIRVGlobalRegistry::createSPIRVType(
                       : getOpTypeInt(Width, MIRBuilder, false);
   }
   if (Ty->isFloatingPointTy()) {
+    if (Ty->isFP128Ty() || Ty->isPPC_FP128Ty()) {
+      Function &F = MIRBuilder.getMF().getFunction();
+      F.getContext().diagnose(DiagnosticInfoUnsupported(
+          F, "fp128 is not supported in SPIR-V", DebugLoc(), DS_Error));
+      return getOpTypeFloat(64, MIRBuilder);
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aobolensk wrote:

Is fatal error acceptable for such case? That seems to be a pattern for `reportFatalUsageError` then since we cannot return anything

https://github.com/llvm/llvm-project/pull/208397