[llvm] [SPIRV] Add support for SPV_KHR_abort extension (PR #193037)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -6250,6 +6253,63 @@ bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
   return true;
 }
 
+bool SPIRVInstructionSelector::selectAbort(MachineInstr &I) const {
+  if (!STI.canUseExtension(SPIRV::Extension::SPV_KHR_abort))
+    report_fatal_error("OpAbortKHR instruction requires the following "
+                       "SPIR-V extension: SPV_KHR_abort",
+                       false);
+  // The intrinsic is declared as variadic so it can carry composite message
+  // types (vectors and structs) without LLVM IR mangling restrictions, but
+  // OpAbortKHR takes exactly one Message operand.
+  if (I.getNumExplicitOperands() != 2)
+    report_fatal_error("llvm.spv.abort must be called with exactly one "
+                       "message argument",
+                       false);
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jmmartinez wrote:

This kind of check should never happen in well-formed LLVM-IR right?

You could do it in the verifier. Or put an `assert(I.getNumExplicitOperands() == 2);` for the developers.

https://github.com/llvm/llvm-project/pull/193037