[llvm] [SystemZ] Introduce GNU and HLASM differences to asmwriter and update tests (PR #113369)

[Ulrich Weigand via llvm-commits]

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@@ -30,6 +30,12 @@ void SystemZHLASMInstPrinter::printInst(const MCInst *MI, uint64_t Address,
                                         StringRef Annot,
                                         const MCSubtargetInfo &STI,
                                         raw_ostream &O) {
-  printInstruction(MI, Address, O);
+  std::string Str;
+  raw_string_ostream RSO(Str);
+  printInstruction(MI, Address, RSO);
+  // Eat the first tab character and replace it with a space since it is
+  // hardcoded in AsmWriterEmitter::EmitPrintInstruction
+  // TODO: introduce a line prefix member to AsmWriter to avoid this problem
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uweigand wrote:

Can we at least verify here that the skipped character is indeed a tab?

https://github.com/llvm/llvm-project/pull/113369