[llvm] [TableGen] Gracefully error out in ParseTreePattern when DAG has zero operands so that llvm-tblgen doesn't crash (PR #161417)

[Prerona Chaudhuri via llvm-commits]

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@@ -19,21 +19,21 @@ def INSTR_BAR : Instruction {
 }
 
 #ifdef ERROR1
-// ERROR1: [[@LINE+1]]:1: error: {{.*}} Invalid number of type casts!
+// ERROR1: error: Invalid number of type casts!
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pchaudhuri-nv wrote:

Thank you for cooperation, I have updated the MR. Kindly let me know if this is good to be checked in.

https://github.com/llvm/llvm-project/pull/161417