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

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -595,6 +598,62 @@ SPIRVPrepareFunctions::removeAggregateTypesFromSignature(Function *F) {
   return NewF;
 }
 
+// Replace OpenCL/SPIR-V style calls to `__spirv_AbortKHR(message)` with calls
+// to the `llvm.spv.abort` target intrinsic, so that they go through the same
+// instruction-selection path as the intrinsic and get lowered to OpAbortKHR.
+bool SPIRVPrepareFunctions::substituteAbortKHRCalls(Function *F) {
+  if (F->isDeclaration())
+    return false;
+
+  SmallVector<CallInst *> Calls;
+  for (Instruction &I : instructions(F)) {
+    auto *CI = dyn_cast<CallInst>(&I);
+    if (!CI)
+      continue;
+    Function *Callee = CI->getCalledFunction();
+    if (!Callee || Callee->isIntrinsic())
+      continue;
+    StringRef Demangled = Callee->getName();
+    std::string DemangledStr = getOclOrSpirvBuiltinDemangledName(Demangled);
+    if (DemangledStr.empty())
+      continue;
+    std::string BuiltinName = SPIRV::lookupBuiltinNameHelper(DemangledStr);
+    if (StringRef(BuiltinName) != "__spirv_AbortKHR")
+      continue;
+    if (CI->arg_size() != 1)
+      continue;
+    Calls.push_back(CI);
+  }
----------------
jmmartinez wrote:

You should do this the other way around, scan the functions in the module looking for `__spirv_AbortKHR`; then do the replacement on its Users.

Otherwise we scan the whole module even if `__spirv_AbortKHR` is not used.

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