[llvm] [llvm-debuginfo-analyzer] Add support for LLVM IR format. (PR #135440)

[Carlos Alberto Enciso via llvm-commits]

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@@ -0,0 +1,2309 @@
+//===-- LVIRReader.cpp ----------------------------------------------------===//
+//
+// 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 implements the LVIRReader class.
+// It supports LLVM text IR and bitcode format.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/LogicalView/Readers/LVIRReader.h"
+#include "llvm/CodeGen/DebugHandlerBase.h"
+#include "llvm/DebugInfo/LogicalView/Core/LVLine.h"
+#include "llvm/DebugInfo/LogicalView/Core/LVScope.h"
+#include "llvm/DebugInfo/LogicalView/Core/LVSymbol.h"
+#include "llvm/DebugInfo/LogicalView/Core/LVType.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/IR/IntrinsicInst.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IRReader/IRReader.h"
+#include "llvm/Object/Error.h"
+#include "llvm/Object/IRObjectFile.h"
+#include "llvm/Support/FormatAdapters.h"
+#include "llvm/Support/FormatVariadic.h"
+#include "llvm/Support/SourceMgr.h"
+
+using namespace llvm;
+using namespace llvm::object;
+using namespace llvm::logicalview;
+
+#define DEBUG_TYPE "IRReader"
+
+// These flavours of DINodes are not implemented but technically possible:
+//   DW_TAG_APPLE_property   = 0x4200
+//   DW_TAG_atomic_type      = 0x0047
+//   DW_TAG_common_block     = 0x001a
+//   DW_TAG_file_type        = 0x0029
+//   DW_TAG_friend           = 0x002a
+//   DW_TAG_generic_subrange = 0x0045
+//   DW_TAG_immutable_type   = 0x004b
+//   DW_TAG_module           = 0x001e
+//   DW_TAG_variant_part     = 0x0033
+
+// Create a logical element and setup the following information:
+// - Name, DWARF tag, line
+// - Collect any file information
+LVElement *LVIRReader::constructElement(const DINode *DN) {
+  dwarf::Tag Tag = DN->getTag();
+  LVElement *Element = createElement(Tag);
+  if (Element) {
+    Element->setTag(Tag);
+    addMD(DN, Element);
+
+    StringRef Name = getMDName(DN);
+    if (!Name.empty())
+      Element->setName(Name);
+
+    // Record any file information.
+    if (const DIFile *File = getMDFile(DN))
+      getOrCreateSourceID(File);
+  }
+
+  return Element;
+}
+
+void LVIRReader::mapFortranLanguage(unsigned DWLang) {
----------------
CarlosAlbertoEnciso wrote:

Good point. Now we use `LVSourceLanguage`:
```
void LVIRReader::setDefaultLowerBound(LVSourceLanguage *SL) {
  assert(SL && "Invalid language ID.");
  StringRef LanguageName = SL->getName();

  // Fortran uses 1 as the default lowerbound; other languages use 0.
  DefaultLowerBound = LanguageName.contains("fortran") ? 1 : 0;

  LLVM_DEBUG({ dbgs() << "Language Name: " << LanguageName << "\n"; });
}
```
Now it covers `DWARF` and `CodeView`.

https://github.com/llvm/llvm-project/pull/135440