[llvm] [LoongArch][Disassembler] Add symbolic operands for decoded immediates (PR #217971)

[via llvm-commits]

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@@ -0,0 +1,189 @@
+//===- LoongArchMCDisassemblerTest.cpp - LoongArch disassembler tests -----===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCDisassembler/MCDisassembler.h"
+#include "llvm/MC/MCDisassembler/MCSymbolizer.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/raw_ostream.h"
+#include "gtest/gtest.h"
+#include <array>
+#include <cassert>
+#include <memory>
+#include <string>
+
+using namespace llvm;
+
+namespace {
+
+struct Context {
+  const Triple TT{"loongarch64-unknown-linux-gnu"};
+  std::unique_ptr<MCRegisterInfo> MRI;
+  std::unique_ptr<MCAsmInfo> MAI;
+  std::unique_ptr<MCContext> Ctx;
+  std::unique_ptr<MCSubtargetInfo> STI;
+  std::unique_ptr<MCDisassembler> DisAsm;
+
+  Context() {
+    LLVMInitializeLoongArchTargetInfo();
+    LLVMInitializeLoongArchTargetMC();
+    LLVMInitializeLoongArchDisassembler();
+
+    std::string Error;
+    const Target *TheTarget = TargetRegistry::lookupTarget(TT, Error);
+    assert(TheTarget && "LoongArch target is not available");
+
+    MRI.reset(TheTarget->createMCRegInfo(TT));
+    MAI.reset(TheTarget->createMCAsmInfo(*MRI, TT, MCTargetOptions()));
+    STI.reset(TheTarget->createMCSubtargetInfo(TT, "", ""));
+    Ctx = std::make_unique<MCContext>(TT, *MAI, *MRI, *STI);
+    DisAsm.reset(TheTarget->createMCDisassembler(*STI, *Ctx));
+  }
+
+  operator MCContext &() { return *Ctx; }
+};
+
+Context &getContext() {
+  static Context Ctx;
+  return Ctx;
+}
+
+class RecordingSymbolizer : public MCSymbolizer {
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zhaoqi5 wrote:

```suggestion
class LoongArchMCSymbolizerTest : public MCSymbolizer {
```

https://github.com/llvm/llvm-project/pull/217971