[llvm] [IR] Add CallBr intrinsics support (PR #133907)

[Matt Arsenault via llvm-commits]

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@@ -3249,11 +3249,30 @@ void Verifier::visitIndirectBrInst(IndirectBrInst &BI) {
 }
 
 void Verifier::visitCallBrInst(CallBrInst &CBI) {
-  Check(CBI.isInlineAsm(), "Callbr is currently only used for asm-goto!", &CBI);
-  const InlineAsm *IA = cast<InlineAsm>(CBI.getCalledOperand());
-  Check(!IA->canThrow(), "Unwinding from Callbr is not allowed");
+  if (!CBI.isInlineAsm()) {
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arsenm wrote:

Need tests in test/Verifier, and the valid cases in test/Assembler 

https://github.com/llvm/llvm-project/pull/133907