From c9093afce5e27b13fa6fad9a68b2d5595eed2916 Mon Sep 17 00:00:00 2001
From: RonxBulld <526677628@qq.com>
Date: Sat, 26 Mar 2022 13:11:43 +0800
Subject: [PATCH] Provide a switch option 'newscope' to determine whether
 different BasicBlocks of the same Subprogram have different DIScopes.

---
 DebugIR.cpp | 13 ++++++++-----
 DebugIR.h   |  4 ++++
 Main.cpp    |  8 +++++++-
 3 files changed, 19 insertions(+), 6 deletions(-)

diff --git a/DebugIR.cpp b/DebugIR.cpp
index 2f9889494..56209d83c 100644
--- a/DebugIR.cpp
+++ b/DebugIR.cpp
@@ -126,7 +126,7 @@ class DIUpdater : public InstVisitor<DIUpdater> {
   int tempNameCounter;
 
   ValueMap<const Function *, DISubprogram *> SubprogramDescriptors;
-  ValueMap<const BasicBlock *, DILexicalBlock *> BlockDescriptors;
+  ValueMap<const Value *, DILexicalBlock *> ScopeDescriptors;
   DenseMap<const Type *, DIType *> TypeDescriptors;
 
 public:
@@ -296,9 +296,10 @@ class DIUpdater : public InstVisitor<DIUpdater> {
   }
 
   DIScope *getBlockScope(DIScope *ParentScope, const BasicBlock *B) {
-    auto BScope = BlockDescriptors.find(B);
-    if (BScope != BlockDescriptors.end()) {
-      return BScope->second;
+    auto S = BBAlwaysNewScope ? dyn_cast<Value>(B) : dyn_cast<Value>(B->getParent());
+    auto ScopeIt = ScopeDescriptors.find(S);
+    if (ScopeIt != ScopeDescriptors.end()) {
+      return ScopeIt->second;
     } else {
       // Let's build a scope for this block.
       unsigned Line = 0;
@@ -308,7 +309,7 @@ class DIUpdater : public InstVisitor<DIUpdater> {
                           << B->getParent()->getName().str() << "\n");
       }
       auto Scope = Builder.createLexicalBlock(ParentScope, FileNode, Line, 0);
-      BlockDescriptors[B] = Scope;
+      ScopeDescriptors[S] = Scope;
       return Scope;
     }
   }
@@ -496,6 +497,8 @@ class DIUpdater : public InstVisitor<DIUpdater> {
 
 namespace llvm {
 
+bool BBAlwaysNewScope = false;
+
 std::unique_ptr<Module> createDebugInfo(Module &M, std::string Directory,
                                         std::string Filename) {
 
diff --git a/DebugIR.h b/DebugIR.h
index 1ebd4b215..4ab465c67 100644
--- a/DebugIR.h
+++ b/DebugIR.h
@@ -18,6 +18,10 @@
 
 namespace llvm {
 
+// Each BasicBlock uses a different DIScope.
+// Default is false.
+extern bool BBAlwaysNewScope;
+
 // Attaches debug info to M, assuming it is parsed from Directory/Filename.
 // Returns a module for display in debugger devoid of any debug info.
 std::unique_ptr<llvm::Module>
diff --git a/Main.cpp b/Main.cpp
index 452de8db7..ead067c4b 100644
--- a/Main.cpp
+++ b/Main.cpp
@@ -32,12 +32,18 @@ using namespace llvm;
 namespace {
 
 // Command line arguments parsed using LLVM's command line parser.
-cl::opt<std::string> InputFile(cl::Positional, cl::desc("<Input file>"),
+cl::opt<std::string> InputFile(cl::Positional, cl::desc("<Input files ...>"),
                                cl::Required);
 cl::opt<bool>
     RunInstNamer("instnamer",
                  cl::desc("Run instnamer on input, prior to processing it"));
 
+cl::opt<bool, true>
+    AlwaysNew("newscope",
+              cl::desc("Each BasicBlock uses a different DIScope."),
+              cl::location(BBAlwaysNewScope),
+              cl::init(false));
+
 void versionPrinter(llvm::raw_ostream &OS) { OS << "debugir: v0.1.0\n"; }
 
 ExitOnError ExitOnErr;