AsmWriter: Print the argument names in declarations while debugging

When llvm declarations have argument names, it's helpful to actually
print those names when debugging. Arguably, it'd be nice to print them
all the time, but that would mean the IR we output wouldn't round trip
through bitcode, which doesn't store the names.

Make the varous print() methods in AsmWriter optionally print "for
debug" and set that flag in the dump() methods. The only thing this
does differently for now is print the argument names in declarations.

llvm-svn: 248692

1 files changed, 31 insertions, 23 deletions

diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index 3387657129c..7731d332a65 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -2005,6 +2005,7 @@ class AssemblyWriter {
   TypePrinting TypePrinter;
   AssemblyAnnotationWriter *AnnotationWriter;
   SetVector<const Comdat *> Comdats;
+  bool IsForDebug;
   bool ShouldPreserveUseListOrder;
   UseListOrderStack UseListOrders;
   SmallVector<StringRef, 8> MDNames;
@@ -2012,7 +2013,7 @@ class AssemblyWriter {
 public:
   /// Construct an AssemblyWriter with an external SlotTracker
   AssemblyWriter(formatted_raw_ostream &o, SlotTracker &Mac, const Module *M,
-                 AssemblyAnnotationWriter *AAW,
+                 AssemblyAnnotationWriter *AAW, bool IsForDebug,
                  bool ShouldPreserveUseListOrder = false);
 
   void printMDNodeBody(const MDNode *MD);
@@ -2063,8 +2064,9 @@ private:
 
 AssemblyWriter::AssemblyWriter(formatted_raw_ostream &o, SlotTracker &Mac,
                                const Module *M, AssemblyAnnotationWriter *AAW,
-                               bool ShouldPreserveUseListOrder)
+                               bool IsForDebug, bool ShouldPreserveUseListOrder)
     : Out(o), TheModule(M), Machine(Mac), AnnotationWriter(AAW),
+      IsForDebug(IsForDebug),
       ShouldPreserveUseListOrder(ShouldPreserveUseListOrder) {
   if (!TheModule)
     return;
@@ -2565,7 +2567,7 @@ void AssemblyWriter::printFunction(const Function *F) {
   Machine.incorporateFunction(F);
 
   // Loop over the arguments, printing them...
-  if (F->isDeclaration()) {
+  if (F->isDeclaration() && !IsForDebug) {
     // We're only interested in the type here - don't print argument names.
     for (unsigned I = 0, E = FT->getNumParams(); I != E; ++I) {
       // Insert commas as we go... the first arg doesn't get a comma
@@ -3234,21 +3236,22 @@ void AssemblyWriter::printUseLists(const Function *F) {
 //===----------------------------------------------------------------------===//
 
 void Module::print(raw_ostream &ROS, AssemblyAnnotationWriter *AAW,
-                   bool ShouldPreserveUseListOrder) const {
+                   bool ShouldPreserveUseListOrder, bool IsForDebug) const {
   SlotTracker SlotTable(this);
   formatted_raw_ostream OS(ROS);
-  AssemblyWriter W(OS, SlotTable, this, AAW, ShouldPreserveUseListOrder);
+  AssemblyWriter W(OS, SlotTable, this, AAW, IsForDebug,
+                   ShouldPreserveUseListOrder);
   W.printModule(this);
 }
 
-void NamedMDNode::print(raw_ostream &ROS) const {
+void NamedMDNode::print(raw_ostream &ROS, bool IsForDebug) const {
   SlotTracker SlotTable(getParent());
   formatted_raw_ostream OS(ROS);
-  AssemblyWriter W(OS, SlotTable, getParent(), nullptr);
+  AssemblyWriter W(OS, SlotTable, getParent(), nullptr, IsForDebug);
   W.printNamedMDNode(this);
 }
 
-void Comdat::print(raw_ostream &ROS) const {
+void Comdat::print(raw_ostream &ROS, bool /*IsForDebug*/) const {
   PrintLLVMName(ROS, getName(), ComdatPrefix);
   ROS << " = comdat ";
 
@@ -3273,7 +3276,7 @@ void Comdat::print(raw_ostream &ROS) const {
   ROS << '\n';
 }
 
-void Type::print(raw_ostream &OS) const {
+void Type::print(raw_ostream &OS, bool /*IsForDebug*/) const {
   TypePrinting TP;
   TP.print(const_cast<Type*>(this), OS);
 
@@ -3296,7 +3299,7 @@ static bool isReferencingMDNode(const Instruction &I) {
   return false;
 }
 
-void Value::print(raw_ostream &ROS) const {
+void Value::print(raw_ostream &ROS, bool IsForDebug) const {
   bool ShouldInitializeAllMetadata = false;
   if (auto *I = dyn_cast<Instruction>(this))
     ShouldInitializeAllMetadata = isReferencingMDNode(*I);
@@ -3304,10 +3307,11 @@ void Value::print(raw_ostream &ROS) const {
     ShouldInitializeAllMetadata = true;
 
   ModuleSlotTracker MST(getModuleFromVal(this), ShouldInitializeAllMetadata);
-  print(ROS, MST);
+  print(ROS, MST, IsForDebug);
 }
 
-void Value::print(raw_ostream &ROS, ModuleSlotTracker &MST) const {
+void Value::print(raw_ostream &ROS, ModuleSlotTracker &MST,
+                  bool IsForDebug) const {
   formatted_raw_ostream OS(ROS);
   SlotTracker EmptySlotTable(static_cast<const Module *>(nullptr));
   SlotTracker &SlotTable =
@@ -3319,14 +3323,14 @@ void Value::print(raw_ostream &ROS, ModuleSlotTracker &MST) const {
 
   if (const Instruction *I = dyn_cast<Instruction>(this)) {
     incorporateFunction(I->getParent() ? I->getParent()->getParent() : nullptr);
-    AssemblyWriter W(OS, SlotTable, getModuleFromVal(I), nullptr);
+    AssemblyWriter W(OS, SlotTable, getModuleFromVal(I), nullptr, IsForDebug);
     W.printInstruction(*I);
   } else if (const BasicBlock *BB = dyn_cast<BasicBlock>(this)) {
     incorporateFunction(BB->getParent());
-    AssemblyWriter W(OS, SlotTable, getModuleFromVal(BB), nullptr);
+    AssemblyWriter W(OS, SlotTable, getModuleFromVal(BB), nullptr, IsForDebug);
     W.printBasicBlock(BB);
   } else if (const GlobalValue *GV = dyn_cast<GlobalValue>(this)) {
-    AssemblyWriter W(OS, SlotTable, GV->getParent(), nullptr);
+    AssemblyWriter W(OS, SlotTable, GV->getParent(), nullptr, IsForDebug);
     if (const GlobalVariable *V = dyn_cast<GlobalVariable>(GV))
       W.printGlobal(V);
     else if (const Function *F = dyn_cast<Function>(GV))
@@ -3428,41 +3432,45 @@ void Metadata::printAsOperand(raw_ostream &OS, ModuleSlotTracker &MST,
   printMetadataImpl(OS, *this, MST, M, /* OnlyAsOperand */ true);
 }
 
-void Metadata::print(raw_ostream &OS, const Module *M) const {
+void Metadata::print(raw_ostream &OS, const Module *M,
+                     bool /*IsForDebug*/) const {
   ModuleSlotTracker MST(M, isa<MDNode>(this));
   printMetadataImpl(OS, *this, MST, M, /* OnlyAsOperand */ false);
 }
 
 void Metadata::print(raw_ostream &OS, ModuleSlotTracker &MST,
-                     const Module *M) const {
+                     const Module *M, bool /*IsForDebug*/) const {
   printMetadataImpl(OS, *this, MST, M, /* OnlyAsOperand */ false);
 }
 
 // Value::dump - allow easy printing of Values from the debugger.
 LLVM_DUMP_METHOD
-void Value::dump() const { print(dbgs()); dbgs() << '\n'; }
+void Value::dump() const { print(dbgs(), /*IsForDebug=*/true); dbgs() << '\n'; }
 
 // Type::dump - allow easy printing of Types from the debugger.
 LLVM_DUMP_METHOD
-void Type::dump() const { print(dbgs()); dbgs() << '\n'; }
+void Type::dump() const { print(dbgs(), /*IsForDebug=*/true); dbgs() << '\n'; }
 
 // Module::dump() - Allow printing of Modules from the debugger.
 LLVM_DUMP_METHOD
-void Module::dump() const { print(dbgs(), nullptr); }
+void Module::dump() const {
+  print(dbgs(), nullptr,
+        /*ShouldPreserveUseListOrder=*/false, /*IsForDebug=*/true);
+}
 
 // \brief Allow printing of Comdats from the debugger.
 LLVM_DUMP_METHOD
-void Comdat::dump() const { print(dbgs()); }
+void Comdat::dump() const { print(dbgs(), /*IsForDebug=*/true); }
 
 // NamedMDNode::dump() - Allow printing of NamedMDNodes from the debugger.
 LLVM_DUMP_METHOD
-void NamedMDNode::dump() const { print(dbgs()); }
+void NamedMDNode::dump() const { print(dbgs(), /*IsForDebug=*/true); }
 
 LLVM_DUMP_METHOD
 void Metadata::dump() const { dump(nullptr); }
 
 LLVM_DUMP_METHOD
 void Metadata::dump(const Module *M) const {
-  print(dbgs(), M);
+  print(dbgs(), M, /*IsForDebug=*/true);
   dbgs() << '\n';
 }