DebugInfo: Remove DwarfDebug::CurrentFnArguments since we have to handle argument...

While refactoring this code I was confused by both the name I had
introduced (addNonArgumentVariable... but it has all this logic to
handle argument numbering and keep things in order?) and by the
redundancy. Seems when I fixed the misordered inlined argument handling,
I didn't realize it was mostly redundant with the argument ordering code
(which I may've also written, I'm not sure). So let's just rely on the
more general case.

The only oddity in output this produces is that it means when we emit
all the variables for the current function, we don't track when we've
finished the argument variables and are about to start the local
variables and insert DW_AT_unspecified_parameters (for varargs
functions) there. Instead it ends up after the local variables, scopes,
etc. But this isn't invalid and doesn't cause DWARF consumers problems
that I know of... so we'll just go with that because it makes the code
nice & simple.

(though, let's see what the buildbots have to say about this - *crosses
fingers*)

There will be some cleanup commits to follow to remove the now trivial
wrappers, etc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@220527 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
index e14ac5ac7f6c0aadc246e20296996161bc5bb462..f1ee52da8d480d3bc748ef585cd3c0ca70cfad0a 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp
@@ -556,31 +556,21 @@ void DwarfCompileUnit::constructSubprogramScopeDIE(LexicalScope *Scope) {
 
   DIE &ScopeDIE = updateSubprogramScopeDIE(Sub);
 
-  // Collect arguments for current function.
-  DIE *ObjectPointer = nullptr;
-  for (DbgVariable *ArgDV : DD->getCurrentFnArguments())
-    if (ArgDV)
-      ScopeDIE.addChild(constructVariableDIE(*ArgDV, *Scope, ObjectPointer));
-
   // If this is a variadic function, add an unspecified parameter.
   DITypeArray FnArgs = Sub.getType().getTypeArray();
+
+  // Collect lexical scope children first.
+  // ObjectPointer might be a local (non-argument) local variable if it's a
+  // block's synthetic this pointer.
+  if (DIE *ObjectPointer = createAndAddScopeChildren(Scope, ScopeDIE))
+    addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
+
   // If we have a single element of null, it is a function that returns void.
   // If we have more than one elements and the last one is null, it is a
   // variadic function.
   if (FnArgs.getNumElements() > 1 &&
       !FnArgs.getElement(FnArgs.getNumElements() - 1))
     ScopeDIE.addChild(make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
-
-  // Collect lexical scope children first.
-  // ObjectPointer might be a local (non-argument) local variable if it's a
-  // block's synthetic this pointer.
-  if (DIE *BlockObjPtr = createAndAddScopeChildren(Scope, ScopeDIE)) {
-    assert(!ObjectPointer && "multiple object pointers can't be described");
-    ObjectPointer = BlockObjPtr;
-  }
-
-  if (ObjectPointer)
-    addDIEEntry(ScopeDIE, dwarf::DW_AT_object_pointer, *ObjectPointer);
 }
 
 DIE *DwarfCompileUnit::createAndAddScopeChildren(LexicalScope *Scope,

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 29685abab48a3d3db980963a6a0db16a84240715..12915d8a48bf217ca05d60bd060ebf9ca3884348 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -1254,8 +1254,6 @@ void DwarfDebug::beginFunction(const MachineFunction *MF) {
 }
 
 void DwarfDebug::addScopeVariable(LexicalScope *LS, DbgVariable *Var) {
-  if (InfoHolder.addCurrentFnArgument(Var, LS))
-    return;
   InfoHolder.addNonArgumentScopeVariable(LS, Var);
 }
 
@@ -1297,7 +1295,6 @@ void DwarfDebug::endFunction(const MachineFunction *MF) {
   if (TheCU.getCUNode().getEmissionKind() == DIBuilder::LineTablesOnly &&
       LScopes.getAbstractScopesList().empty() && !IsDarwin) {
     assert(ScopeVariables.empty());
-    assert(CurrentFnArguments.empty());
     assert(DbgValues.empty());
     // FIXME: This wouldn't be true in LTO with a -g (with inlining) CU followed
     // by a -gmlt CU. Add a test and remove this assertion.
@@ -1337,7 +1334,6 @@ void DwarfDebug::endFunction(const MachineFunction *MF) {
   // DbgVariables except those that are also in AbstractVariables (since they
   // can be used cross-function)
   ScopeVariables.clear();
-  CurrentFnArguments.clear();
   DbgValues.clear();
   LabelsBeforeInsn.clear();
   LabelsAfterInsn.clear();

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.h b/lib/CodeGen/AsmPrinter/DwarfDebug.h
index d1fae7285f5f777032d19df0827a68f9ade12261..927ef76e4bdad9069a7d1845d5f1895b4fdf5054 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.h
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.h
@@ -194,9 +194,6 @@ class DwarfDebug : public AsmPrinterHandler {
   typedef DenseMap<const MCSection *, SmallVector<SymbolCU, 8> > SectionMapType;
   SectionMapType SectionMap;
 
-  // List of arguments for current function.
-  SmallVector<DbgVariable *, 8> CurrentFnArguments;
-
   LexicalScopes LScopes;
 
   // Collection of abstract subprogram DIEs.
@@ -675,10 +672,6 @@ public:
   SmallPtrSet<const MDNode *, 16> &getProcessedSPNodes() {
     return ProcessedSPNodes;
   }
-
-  SmallVector<DbgVariable *, 8> &getCurrentFnArguments() {
-    return CurrentFnArguments;
-  }
 };
 } // End of namespace llvm
 

diff --git a/lib/CodeGen/AsmPrinter/DwarfFile.cpp b/lib/CodeGen/AsmPrinter/DwarfFile.cpp
index 6b3d148ee06dc5135ca2e543edbe06ddf3231e5f..0d92169587b6d5ae80126b4bcf6bbf0d7524f9d8 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfFile.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfFile.cpp
@@ -155,28 +155,6 @@ void DwarfFile::emitStrings(const MCSection *StrSection,
   StrPool.emit(*Asm, StrSection, OffsetSection);
 }
 
-// If Var is a current function argument then add it to CurrentFnArguments list.
-bool DwarfFile::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
-  if (Scope->getParent())
-    return false;
-  DIVariable DV = Var->getVariable();
-  if (DV.getTag() != dwarf::DW_TAG_arg_variable)
-    return false;
-  unsigned ArgNo = DV.getArgNumber();
-  if (ArgNo == 0)
-    return false;
-
-  auto &CurrentFnArguments = DD.getCurrentFnArguments();
-
-  // llvm::Function argument size is not good indicator of how many
-  // arguments does the function have at source level.
-  if (ArgNo > CurrentFnArguments.size())
-    CurrentFnArguments.resize(ArgNo * 2);
-  assert(!CurrentFnArguments[ArgNo - 1]);
-  CurrentFnArguments[ArgNo - 1] = Var;
-  return true;
-}
-
 void DwarfFile::addNonArgumentScopeVariable(LexicalScope *LS,
                                             DbgVariable *Var) {
   SmallVectorImpl<DbgVariable *> &Vars = DD.getScopeVariables()[LS];
@@ -200,6 +178,7 @@ void DwarfFile::addNonArgumentScopeVariable(LexicalScope *LS,
       // A later indexed parameter has been found, insert immediately before it.
       if (CurNum > ArgNum)
         break;
+      assert(CurNum != ArgNum);
       ++I;
     }
     Vars.insert(I, Var);

diff --git a/lib/CodeGen/AsmPrinter/DwarfFile.h b/lib/CodeGen/AsmPrinter/DwarfFile.h
index 0ce9072fb1ee48a139a20014ea0b7fba221a1b83..011b5de6c6ecf33898f45d5df6a7f27b654a2c2e 100644 (file)
--- a/lib/CodeGen/AsmPrinter/DwarfFile.h
+++ b/lib/CodeGen/AsmPrinter/DwarfFile.h
@@ -84,7 +84,6 @@ public:
   /// \brief Returns the string pool.
   DwarfStringPool &getStringPool() { return StrPool; }
 
-  bool addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope);
   void addNonArgumentScopeVariable(LexicalScope *LS, DbgVariable *Var);
 };
 }

diff --git a/test/DebugInfo/varargs.ll b/test/DebugInfo/varargs.ll
index 5f64030acac0e488f9882297727ab000a5a6a96b..1fe598a76a330dc84342d3365b09c0f6f0534c95 100644 (file)
--- a/test/DebugInfo/varargs.ll
+++ b/test/DebugInfo/varargs.ll
@@ -27,6 +27,10 @@
 ; CHECK-NOT: DW_TAG
 ; CHECK: DW_TAG_formal_parameter
 ; CHECK-NOT: DW_TAG
+; CHECK: DW_TAG_variable
+; CHECK-NOT: DW_TAG
+; CHECK: DW_TAG_variable
+; CHECK-NOT: DW_TAG
 ; CHECK: DW_TAG_unspecified_parameters
 ;
 ; Variadic C++ member function.