[llvm] [Xtensa] Implement base CallConvention. (PR #83280)

[Matt Arsenault via llvm-commits]

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@@ -0,0 +1,87 @@
+//===-- XtensaTargetStreamer.cpp - Xtensa Target Streamer Methods ---------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides Xtensa specific target streamer methods.
+//
+//===----------------------------------------------------------------------===//
+
+#include "XtensaTargetStreamer.h"
+#include "XtensaInstPrinter.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/Support/FormattedStream.h"
+
+using namespace llvm;
+
+XtensaTargetStreamer::XtensaTargetStreamer(MCStreamer &S)
+    : MCTargetStreamer(S) {}
+
+XtensaTargetAsmStreamer::XtensaTargetAsmStreamer(MCStreamer &S,
+                                                 formatted_raw_ostream &OS)
+    : XtensaTargetStreamer(S), OS(OS) {}
+
+void XtensaTargetAsmStreamer::emitLiteral(MCSymbol *LblSym, const MCExpr *Value,
+                                          SMLoc L) {
+  const MCAsmInfo *MAI = Streamer.getContext().getAsmInfo();
+
+  OS << "\t.literal\t";
+  LblSym->print(OS, MAI);
+  OS << ", ";
+  Value->print(OS, MAI);
+  OS << '\n';
+}
+
+void XtensaTargetAsmStreamer::emitLiteralPosition() {
+  OS << "\t.literal_position\n";
+}
+
+XtensaTargetELFStreamer::XtensaTargetELFStreamer(MCStreamer &S)
+    : XtensaTargetStreamer(S) {}
+
+static std::string getLiteralSectionName(std::string CSectionName) {
+  std::size_t Pos = CSectionName.find(".text");
+  std::string SectionName;
+  if (Pos != std::string::npos) {
+    if (Pos > 0)
+      SectionName = CSectionName.substr(0, Pos + 5);
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arsenm wrote:

can you use consume_front(".text") instead of maintaining this + 5 

https://github.com/llvm/llvm-project/pull/83280