[llvm] [FastISel] Support unreachable with NoTrapAfterNoReturn (PR #118296)

[Matt Arsenault via llvm-commits]

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@@ -1851,11 +1851,19 @@ bool FastISel::selectOperator(const User *I, unsigned Opcode) {
     return false;
   }
 
-  case Instruction::Unreachable:
-    if (TM.Options.TrapUnreachable)
+  case Instruction::Unreachable: {
+    if (TM.Options.TrapUnreachable) {
+      if (TM.Options.NoTrapAfterNoreturn) {
+        const auto *Call =
+            dyn_cast_or_null<CallInst>(cast<Instruction>(I)->getPrevNode());
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arsenm wrote:

CallBase? 

https://github.com/llvm/llvm-project/pull/118296