Add the support code to enable the dwarf accelerator tables. Upcoming patches

to fix the types section (all types, not just global types), and testcases.

The code to do the final emission is disabled by default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143923 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 168 insertions, 0 deletions

diff --git a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
index 037b4ace02..8acc8571dd 100644
--- a/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ b/lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -14,6 +14,7 @@
 #define DEBUG_TYPE "dwarfdebug"
 #include "DwarfDebug.h"
 #include "DIE.h"
+#include "DwarfAccelTable.h"
 #include "DwarfCompileUnit.h"
 #include "llvm/Constants.h"
 #include "llvm/Module.h"
@@ -52,6 +53,10 @@ static cl::opt<bool> UnknownLocations("use-unknown-locations", cl::Hidden,
      cl::desc("Make an absence of debug location information explicit."),
      cl::init(false));
 
+static cl::opt<bool> DwarfAccelTables("dwarf-accel-tables", cl::Hidden,
+     cl::desc("Output prototype dwarf accelerator tables."),
+     cl::init(false));
+
 namespace {
   const char *DWARFGroupName = "DWARF Emission";
   const char *DbgTimerName = "DWARF Debug Writer";
@@ -444,6 +449,9 @@ DIE *DwarfDebug::constructScopeDIE(CompileUnit *TheCU, LexicalScope *Scope) {
   if (DS.isSubprogram())
    TheCU->addPubTypes(DISubprogram(DS));
 
+  if (DS.isSubprogram() && !Scope->isAbstractScope())
+    TheCU->addAccelName(DISubprogram(DS).getName(), ScopeDIE);
+
  return ScopeDIE;
 }
 
@@ -524,6 +532,36 @@ CompileUnit *DwarfDebug::constructCompileUnit(const MDNode *N) {
   return NewCU;
 }
 
+static bool isObjCClass(StringRef Name) {
+  return Name[0] == '+' || Name[0] == '-';
+}
+
+static bool hasObjCCategory(StringRef Name) {
+  if (Name[0] != '+' && Name[0] != '-')
+    return false;
+
+  size_t pos = Name.find(')');
+  if (pos != std::string::npos) {
+    if (Name[pos+1] != ' ') return false;
+    return true;
+  }
+
+  return false;
+}
+
+static void getObjCClassCategory(StringRef In, StringRef &Class,
+                                 StringRef &Category) {
+  if (!hasObjCCategory(In)) {
+    Class = In.slice(In.find('[') + 1, In.find(' '));
+    Category = "";
+    return;
+  }
+
+  Class = In.slice(In.find('[') + 1, In.find('('));
+  Category = In.slice(In.find('[') + 1, In.find(' '));
+  return;
+}
+
 /// construct SubprogramDIE - Construct subprogram DIE.
 void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU, 
                                         const MDNode *N) {
@@ -561,6 +599,18 @@ void DwarfDebug::constructSubprogramDIE(CompileUnit *TheCU,
   // Expose as global.
   TheCU->addGlobal(SP.getName(), SubprogramDie);
 
+  // Add to Accel Names
+  TheCU->addAccelName(SP.getName(), SubprogramDie);
+
+  // If this is an Objective-C selector name add it to the ObjC accelerator too.
+  if (isObjCClass(SP.getName())) {
+    StringRef Class, Category;
+    getObjCClassCategory(SP.getName(), Class, Category);
+    TheCU->addAccelObjC(Class, SubprogramDie);
+    if (Category != "")
+      TheCU->addAccelObjC(Category, SubprogramDie);
+  }
+  
   return;
 }
 
@@ -757,6 +807,14 @@ void DwarfDebug::endModule() {
   // Corresponding abbreviations into a abbrev section.
   emitAbbreviations();
 
+  // Emit info into a dwarf accelerator table sections.
+  if (DwarfAccelTables) {
+    emitAccelNames();
+    emitAccelObjC();
+    emitAccelNamespaces();
+    emitAccelTypes();
+  }
+  
   // Emit info into a debug pubnames section.
   emitDebugPubNames();
 
@@ -1696,6 +1754,116 @@ void DwarfDebug::emitEndOfLineMatrix(unsigned SectionEnd) {
   Asm->EmitInt8(1);
 }
 
+/// emitAccelNames - Emit visible names into a hashed accelerator table
+/// section.
+void DwarfDebug::emitAccelNames() {
+  DwarfAccelTable AT(DwarfAccelTable::Atom(DwarfAccelTable::eAtomTypeDIEOffset,
+                                           dwarf::DW_FORM_data4));
+  for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(),
+         E = CUMap.end(); I != E; ++I) {
+    CompileUnit *TheCU = I->second;
+    const StringMap<DIE*> &Names = TheCU->getAccelNames();
+    for (StringMap<DIE*>::const_iterator
+           GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) {
+      const char *Name = GI->getKeyData();
+      DIE *Entity = GI->second;
+      AT.AddName(Name, Entity);
+    }
+  }
+
+  AT.FinalizeTable(Asm, "Names");
+  Asm->OutStreamer.SwitchSection(
+    Asm->getObjFileLowering().getDwarfAccelNamesSection());
+  MCSymbol *SectionBegin = Asm->GetTempSymbol("names_begin");
+  Asm->OutStreamer.EmitLabel(SectionBegin);
+
+  // Emit the full data.
+  AT.Emit(Asm, SectionBegin, this);
+}
+
+/// emitAccelObjC - Emit objective C classes and categories into a hashed
+/// accelerator table section.
+void DwarfDebug::emitAccelObjC() {
+  DwarfAccelTable AT(DwarfAccelTable::Atom(DwarfAccelTable::eAtomTypeDIEOffset,
+                                           dwarf::DW_FORM_data4));
+  for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(),
+         E = CUMap.end(); I != E; ++I) {
+    CompileUnit *TheCU = I->second;
+    const StringMap<std::vector<DIE*> > &Names = TheCU->getAccelObjC();
+    for (StringMap<std::vector<DIE*> >::const_iterator
+           GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) {
+      const char *Name = GI->getKeyData();
+      std::vector<DIE *> Entities = GI->second;
+      for (std::vector<DIE *>::const_iterator DI = Entities.begin(),
+             DE = Entities.end(); DI != DE; ++DI)
+        AT.AddName(Name, (*DI));
+    }
+  }
+
+  AT.FinalizeTable(Asm, "ObjC");
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering()
+                                 .getDwarfAccelObjCSection());
+  MCSymbol *SectionBegin = Asm->GetTempSymbol("objc_begin");
+  Asm->OutStreamer.EmitLabel(SectionBegin);
+
+  // Emit the full data.
+  AT.Emit(Asm, SectionBegin, this);
+}
+
+/// emitAccelNamespace - Emit namespace dies into a hashed accelerator
+/// table.
+void DwarfDebug::emitAccelNamespaces() {
+  DwarfAccelTable AT(DwarfAccelTable::Atom(DwarfAccelTable::eAtomTypeDIEOffset,
+                                           dwarf::DW_FORM_data4));
+  for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(),
+         E = CUMap.end(); I != E; ++I) {
+    CompileUnit *TheCU = I->second;
+    const StringMap<DIE*> &Names = TheCU->getAccelNamespace();
+    for (StringMap<DIE*>::const_iterator
+           GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) {
+      const char *Name = GI->getKeyData();
+      DIE *Entity = GI->second;
+      AT.AddName(Name, Entity);
+    }
+  }
+
+  AT.FinalizeTable(Asm, "namespac");
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering()
+                                 .getDwarfAccelNamespaceSection());
+  MCSymbol *SectionBegin = Asm->GetTempSymbol("namespac_begin");
+  Asm->OutStreamer.EmitLabel(SectionBegin);
+
+  // Emit the full data.
+  AT.Emit(Asm, SectionBegin, this);
+}
+
+/// emitAccelTypes() - Emit type dies into a hashed accelerator table.
+void DwarfDebug::emitAccelTypes() {
+  DwarfAccelTable AT(DwarfAccelTable::Atom(DwarfAccelTable::eAtomTypeDIEOffset,
+                                           dwarf::DW_FORM_data4));
+  for (DenseMap<const MDNode *, CompileUnit *>::iterator I = CUMap.begin(),
+         E = CUMap.end(); I != E; ++I) {
+    CompileUnit *TheCU = I->second;
+    const StringMap<DIE*> &Names = TheCU->getGlobalTypes();
+    //TODO: TheCU->getAccelTypes();
+    for (StringMap<DIE*>::const_iterator
+           GI = Names.begin(), GE = Names.end(); GI != GE; ++GI) {
+      const char *Name = GI->getKeyData();
+      DIE *Entity = GI->second;
+      AT.AddName(Name, Entity);
+    }
+  }
+
+  AT.FinalizeTable(Asm, "types");
+  Asm->OutStreamer.SwitchSection(Asm->getObjFileLowering()
+                                 .getDwarfAccelTypesSection());
+  MCSymbol *SectionBegin = Asm->GetTempSymbol("types_begin");
+  Asm->OutStreamer.EmitLabel(SectionBegin);
+
+  // Emit the full data.
+  AT.Emit(Asm, SectionBegin, this);
+}
+
 /// emitDebugPubNames - Emit visible names into a debug pubnames section.
 ///
 void DwarfDebug::emitDebugPubNames() {