[llvm] r206003 - Remove lazy-initialization of section caches in MCContext

David Blaikie dblaikie at gmail.com
Thu Apr 10 16:55:11 PDT 2014


Author: dblaikie
Date: Thu Apr 10 18:55:11 2014
New Revision: 206003

URL: http://llvm.org/viewvc/llvm-project?rev=206003&view=rev
Log:
Remove lazy-initialization of section caches in MCContext

This seems to have been a cargo-culted habit from the very first such
cache which didn't have any specific justification (but might've been a
layering constraint at the time).

Modified:
    llvm/trunk/include/llvm/MC/MCContext.h
    llvm/trunk/lib/MC/MCContext.cpp

Modified: llvm/trunk/include/llvm/MC/MCContext.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/MC/MCContext.h?rev=206003&r1=206002&r2=206003&view=diff
==============================================================================
--- llvm/trunk/include/llvm/MC/MCContext.h (original)
+++ llvm/trunk/include/llvm/MC/MCContext.h Thu Apr 10 18:55:11 2014
@@ -155,7 +155,11 @@ namespace llvm {
     /// The Compile Unit ID that we are currently processing.
     unsigned DwarfCompileUnitID;
 
-    void *MachOUniquingMap, *ELFUniquingMap, *COFFUniquingMap;
+    typedef std::pair<std::string, std::string> SectionGroupPair;
+
+    StringMap<const MCSectionMachO*> MachOUniquingMap;
+    std::map<SectionGroupPair, const MCSectionELF *> ELFUniquingMap;
+    std::map<SectionGroupPair, const MCSectionCOFF *> COFFUniquingMap;
 
     /// Do automatic reset in destructor
     bool AutoReset;

Modified: llvm/trunk/lib/MC/MCContext.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/MC/MCContext.cpp?rev=206003&r1=206002&r2=206003&view=diff
==============================================================================
--- llvm/trunk/lib/MC/MCContext.cpp (original)
+++ llvm/trunk/lib/MC/MCContext.cpp Thu Apr 10 18:55:11 2014
@@ -29,12 +29,6 @@
 
 using namespace llvm;
 
-typedef std::pair<std::string, std::string> SectionGroupPair;
-
-typedef StringMap<const MCSectionMachO*> MachOUniqueMapTy;
-typedef std::map<SectionGroupPair, const MCSectionELF *> ELFUniqueMapTy;
-typedef std::map<SectionGroupPair, const MCSectionCOFF *> COFFUniqueMapTy;
-
 MCContext::MCContext(const MCAsmInfo *mai, const MCRegisterInfo *mri,
                      const MCObjectFileInfo *mofi, const SourceMgr *mgr,
                      bool DoAutoReset)
@@ -49,10 +43,6 @@ MCContext::MCContext(const MCAsmInfo *ma
   if (EC)
     CompilationDir.clear();
 
-  MachOUniquingMap = 0;
-  ELFUniquingMap = 0;
-  COFFUniquingMap = 0;
-
   SecureLogFile = getenv("AS_SECURE_LOG_FILE");
   SecureLog = 0;
   SecureLogUsed = false;
@@ -88,13 +78,9 @@ void MCContext::reset() {
   DwarfCompileUnitID = 0;
   CurrentDwarfLoc = MCDwarfLoc(0,0,0,DWARF2_FLAG_IS_STMT,0,0);
 
-  // If we have the MachO uniquing map, free it.
-  delete (MachOUniqueMapTy*)MachOUniquingMap;
-  delete (ELFUniqueMapTy*)ELFUniquingMap;
-  delete (COFFUniqueMapTy*)COFFUniquingMap;
-  MachOUniquingMap = 0;
-  ELFUniquingMap = 0;
-  COFFUniquingMap = 0;
+  MachOUniquingMap.clear();
+  ELFUniquingMap.clear();
+  COFFUniquingMap.clear();
 
   NextUniqueID = 0;
   AllowTemporaryLabels = true;
@@ -225,11 +211,6 @@ getMachOSection(StringRef Segment, Strin
   // may not have the same flags as the requested section, if so this should be
   // diagnosed by the client as an error.
 
-  // Create the map if it doesn't already exist.
-  if (MachOUniquingMap == 0)
-    MachOUniquingMap = new MachOUniqueMapTy();
-  MachOUniqueMapTy &Map = *(MachOUniqueMapTy*)MachOUniquingMap;
-
   // Form the name to look up.
   SmallString<64> Name;
   Name += Segment;
@@ -237,7 +218,7 @@ getMachOSection(StringRef Segment, Strin
   Name += Section;
 
   // Do the lookup, if we have a hit, return it.
-  const MCSectionMachO *&Entry = Map[Name.str()];
+  const MCSectionMachO *&Entry = MachOUniquingMap[Name.str()];
   if (Entry) return Entry;
 
   // Otherwise, return a new section.
@@ -252,31 +233,25 @@ getELFSection(StringRef Section, unsigne
 }
 
 void MCContext::renameELFSection(const MCSectionELF *Section, StringRef Name) {
-  if (ELFUniquingMap == 0)
-    ELFUniquingMap = new ELFUniqueMapTy();
-  ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)ELFUniquingMap;
-
   StringRef GroupName;
   if (const MCSymbol *Group = Section->getGroup())
     GroupName = Group->getName();
 
-  Map.erase(SectionGroupPair(Section->getSectionName(), GroupName));
-  auto I = Map.insert(std::make_pair(SectionGroupPair(Name, GroupName),
-                                     Section)).first;
+  ELFUniquingMap.erase(SectionGroupPair(Section->getSectionName(), GroupName));
+  auto I =
+      ELFUniquingMap.insert(std::make_pair(SectionGroupPair(Name, GroupName),
+                                           Section)).first;
   const_cast<MCSectionELF*>(Section)->setSectionName(I->first.first);
 }
 
 const MCSectionELF *MCContext::
 getELFSection(StringRef Section, unsigned Type, unsigned Flags,
               SectionKind Kind, unsigned EntrySize, StringRef Group) {
-  if (ELFUniquingMap == 0)
-    ELFUniquingMap = new ELFUniqueMapTy();
-  ELFUniqueMapTy &Map = *(ELFUniqueMapTy*)ELFUniquingMap;
-
   // Do the lookup, if we have a hit, return it.
-  std::pair<ELFUniqueMapTy::iterator, bool> Entry = Map.insert(
+  auto IterBool = ELFUniquingMap.insert(
       std::make_pair(SectionGroupPair(Section, Group), (MCSectionELF *)0));
-  if (!Entry.second) return Entry.first->second;
+  auto &Entry = *IterBool.first;
+  if (!IterBool.second) return Entry.second;
 
   // Possibly refine the entry size first.
   if (!EntrySize) {
@@ -288,8 +263,8 @@ getELFSection(StringRef Section, unsigne
     GroupSym = GetOrCreateSymbol(Group);
 
   MCSectionELF *Result = new (*this) MCSectionELF(
-      Entry.first->first.first, Type, Flags, Kind, EntrySize, GroupSym);
-  Entry.first->second = Result;
+      Entry.first.first, Type, Flags, Kind, EntrySize, GroupSym);
+  Entry.second = Result;
   return Result;
 }
 
@@ -304,17 +279,12 @@ const MCSectionCOFF *
 MCContext::getCOFFSection(StringRef Section, unsigned Characteristics,
                           SectionKind Kind, StringRef COMDATSymName,
                           int Selection, const MCSectionCOFF *Assoc) {
-  if (COFFUniquingMap == 0)
-    COFFUniquingMap = new COFFUniqueMapTy();
-  COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap;
-
   // Do the lookup, if we have a hit, return it.
 
   SectionGroupPair P(Section, COMDATSymName);
-  std::pair<COFFUniqueMapTy::iterator, bool> Entry =
-      Map.insert(std::make_pair(P, (MCSectionCOFF *)0));
-  COFFUniqueMapTy::iterator Iter = Entry.first;
-  if (!Entry.second)
+  auto IterBool = COFFUniquingMap.insert(std::make_pair(P, (MCSectionCOFF *)0));
+  auto Iter = IterBool.first;
+  if (!IterBool.second)
     return Iter->second;
 
   const MCSymbol *COMDATSymbol = NULL;
@@ -336,13 +306,9 @@ MCContext::getCOFFSection(StringRef Sect
 }
 
 const MCSectionCOFF *MCContext::getCOFFSection(StringRef Section) {
-  if (COFFUniquingMap == 0)
-    COFFUniquingMap = new COFFUniqueMapTy();
-  COFFUniqueMapTy &Map = *(COFFUniqueMapTy*)COFFUniquingMap;
-
   SectionGroupPair P(Section, "");
-  COFFUniqueMapTy::iterator Iter = Map.find(P);
-  if (Iter == Map.end())
+  auto Iter = COFFUniquingMap.find(P);
+  if (Iter == COFFUniquingMap.end())
     return 0;
   return Iter->second;
 }





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