[llvm] Remove the optional bitcast between a musttail call and its ret (PR #201280)

[Arseniy Obolenskiy via llvm-commits]

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@@ -4287,32 +4275,21 @@ void Verifier::verifyMustTailCall(CallInst &CI) {
   FunctionType *CalleeTy = CI.getFunctionType();
   Check(CallerTy->isVarArg() == CalleeTy->isVarArg(),
         "cannot guarantee tail call due to mismatched varargs", &CI);
-  Check(isTypeCongruent(CallerTy->getReturnType(), CalleeTy->getReturnType()),
+  Check(CallerTy->getReturnType() == CalleeTy->getReturnType(),
         "cannot guarantee tail call due to mismatched return types", &CI);
 
   // - The calling conventions of the caller and callee must match.
   Check(F->getCallingConv() == CI.getCallingConv(),
         "cannot guarantee tail call due to mismatched calling conv", &CI);
 
-  // - The call must immediately precede a :ref:`ret <i_ret>` instruction,
-  //   or a pointer bitcast followed by a ret instruction.
-  // - The ret instruction must return the (possibly bitcasted) value
-  //   produced by the call or void.
-  Value *RetVal = &CI;
+  // - The call must immediately precede a :ref:`ret <i_ret>` instruction.
+  // - The ret instruction must return the value produced by the call or void.
   Instruction *Next = CI.getNextNode();
 
-  // Handle the optional bitcast.
-  if (BitCastInst *BI = dyn_cast_or_null<BitCastInst>(Next)) {
-    Check(BI->getOperand(0) == RetVal,
-          "bitcast following musttail call must use the call", BI);
-    RetVal = BI;
-    Next = BI->getNextNode();
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aobolensk wrote:

Added, please check

https://github.com/llvm/llvm-project/pull/201280