commit f244922f438ffaacdb092ed37db56068bdda475e
author David Blaikie <dblaikie@gmail.com> Mon Apr 28 20:36:45 2014 +0000
committer David Blaikie <dblaikie@gmail.com> Mon Apr 28 20:36:45 2014 +0000
tree e31bd0e4b3392819bfed48ee87d7f6bf1a4c6832
parent d8f0ac7b4aa79e1d643f5469874603d53d9e6a33

Improve explicit memory ownership of DIEs

Now that the subtle constructScopeDIE has been refactored into two
functions - one returning memory to take ownership of, one returning a
pointer to already owning memory - push unique_ptr through more APIs.

I think this completes most of the unique_ptr ownership of DIEs.

llvm-svn: 207442

llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index c0b8044..f2ab8d2 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -421,12 +421,13 @@
 
 // Construct new DW_TAG_lexical_block for this scope and attach
 // DW_AT_low_pc/DW_AT_high_pc labels.
-DIE *DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
-                                          LexicalScope *Scope) {
+std::unique_ptr<DIE>
+DwarfDebug::constructLexicalScopeDIE(DwarfCompileUnit &TheCU,
+                                     LexicalScope *Scope) {
   if (isLexicalScopeDIENull(Scope))
     return nullptr;
 
-  DIE *ScopeDIE = new DIE(dwarf::DW_TAG_lexical_block);
+  auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_lexical_block);
   if (Scope->isAbstractScope())
     return ScopeDIE;
 
@@ -454,8 +455,9 @@
 
 // This scope represents inlined body of a function. Construct DIE to
 // represent this concrete inlined copy of the function.
-DIE *DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
-                                          LexicalScope *Scope) {
+std::unique_ptr<DIE>
+DwarfDebug::constructInlinedScopeDIE(DwarfCompileUnit &TheCU,
+                                     LexicalScope *Scope) {
   const SmallVectorImpl<InsnRange> &ScopeRanges = Scope->getRanges();
   assert(!ScopeRanges.empty() &&
          "LexicalScope does not have instruction markers!");
@@ -470,7 +472,7 @@
     return nullptr;
   }
 
-  DIE *ScopeDIE = new DIE(dwarf::DW_TAG_inlined_subroutine);
+  auto ScopeDIE = make_unique<DIE>(dwarf::DW_TAG_inlined_subroutine);
   TheCU.addDIEEntry(*ScopeDIE, dwarf::DW_AT_abstract_origin, *OriginDIE);
 
   // If we have multiple ranges, emit them into the range section.
@@ -539,8 +541,8 @@
       ObjectPointer = Children.back().get();
   }
   for (LexicalScope *LS : Scope->getChildren())
-    if (DIE *Nested = constructScopeDIE(TheCU, LS))
-      Children.push_back(std::unique_ptr<DIE>(Nested));
+    if (std::unique_ptr<DIE> Nested = constructScopeDIE(TheCU, LS))
+      Children.push_back(std::move(Nested));
   return ObjectPointer;
 }
 
@@ -582,8 +584,8 @@
 }
 
 // Construct a DIE for this scope.
-DIE *DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
-                                   LexicalScope *Scope) {
+std::unique_ptr<DIE> DwarfDebug::constructScopeDIE(DwarfCompileUnit &TheCU,
+                                                   LexicalScope *Scope) {
   if (!Scope || !Scope->getScopeNode())
     return nullptr;
 
@@ -599,7 +601,7 @@
   // We try to create the scope DIE first, then the children DIEs. This will
   // avoid creating un-used children then removing them later when we find out
   // the scope DIE is null.
-  DIE *ScopeDIE = nullptr;
+  std::unique_ptr<DIE> ScopeDIE;
   if (Scope->getInlinedAt()) {
     ScopeDIE = constructInlinedScopeDIE(TheCU, Scope);
     if (!ScopeDIE)
@@ -629,8 +631,7 @@
     assert(ScopeDIE && "Scope DIE should not be null.");
     for (ImportedEntityMap::const_iterator i = Range.first; i != Range.second;
          ++i)
-      constructImportedEntityDIE(TheCU, i->second, ScopeDIE);
-
+      constructImportedEntityDIE(TheCU, i->second, *ScopeDIE);
   }
 
   // Add children
@@ -739,11 +740,11 @@
   DIImportedEntity Module(N);
   assert(Module.Verify());
   if (DIE *D = TheCU.getOrCreateContextDIE(Module.getContext()))
-    constructImportedEntityDIE(TheCU, Module, D);
+    constructImportedEntityDIE(TheCU, Module, *D);
 }
 
 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
-                                            const MDNode *N, DIE *Context) {
+                                            const MDNode *N, DIE &Context) {
   DIImportedEntity Module(N);
   assert(Module.Verify());
   return constructImportedEntityDIE(TheCU, Module, Context);
@@ -751,11 +752,10 @@
 
 void DwarfDebug::constructImportedEntityDIE(DwarfCompileUnit &TheCU,
                                             const DIImportedEntity &Module,
-                                            DIE *Context) {
+                                            DIE &Context) {
   assert(Module.Verify() &&
          "Use one of the MDNode * overloads to handle invalid metadata");
-  assert(Context && "Should always have a context for an imported_module");
-  DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), *Context, Module);
+  DIE &IMDie = TheCU.createAndAddDIE(Module.getTag(), Context, Module);
   DIE *EntityDie;
   DIDescriptor Entity = resolve(Module.getEntity());
   if (Entity.isNameSpace())