Subzero: Fix symbol name mangling. Make flags global.

src/IceGlobalContext.cpp

Index: src/IceGlobalContext.cpp
diff --git a/src/IceGlobalContext.cpp b/src/IceGlobalContext.cpp
index af3e6c7065e657aa98a4c989f89d64c5a120bc28..25a4ab30ff924798a77be47e401ea40b115278e8 100644
--- a/src/IceGlobalContext.cpp
+++ b/src/IceGlobalContext.cpp
@@ -18,6 +18,7 @@
 #include "IceCfg.h"
 #include "IceCfgNode.h"
 #include "IceClFlags.h"
+#include "IceClFlagsExtra.h"
 #include "IceDefs.h"
 #include "IceELFObjectWriter.h"
 #include "IceGlobalInits.h"
@@ -38,8 +39,6 @@
 #endif // __clang__
 
 #include <algorithm> // max()
-#include <cctype>    // isdigit(), isupper()
-#include <locale>    // locale
 
 namespace std {
 template <> struct hash<Ice::RelocatableTuple> {
@@ -250,9 +249,9 @@ void GlobalContext::CodeStats::dump(const IceString &Name, GlobalContext *Ctx) {
 }
 
 GlobalContext::GlobalContext(Ostream *OsDump, Ostream *OsEmit, Ostream *OsError,
-                             ELFStreamer *ELFStr, const ClFlags &Flags)
+                             ELFStreamer *ELFStr)
     : ConstPool(new ConstantPool()), ErrorStatus(), StrDump(OsDump),
-      StrEmit(OsEmit), StrError(OsError), Flags(Flags), ObjectWriter(),
+      StrEmit(OsEmit), StrError(OsError), ObjectWriter(),
       OptQ(/*Sequential=*/Flags.isSequential(),
            /*MaxSize=*/Flags.getNumTranslationThreads()),
       // EmitQ is allowed unlimited size.
@@ -293,15 +292,13 @@ GlobalContext::GlobalContext(Ostream *OsDump, Ostream *OsEmit, Ostream *OsError,
   // ProfileBlockInfoVarDecl is initialized here because it takes this as a
   // parameter -- we want to
   // ensure that at least this' member variables are initialized.
-  ProfileBlockInfoVarDecl = VariableDeclaration::create(this);
+  ProfileBlockInfoVarDecl = VariableDeclaration::createExternal(this);
   ProfileBlockInfoVarDecl->setAlignment(typeWidthInBytes(IceType_i64));
   ProfileBlockInfoVarDecl->setIsConstant(true);
 
   // Note: if you change this symbol, make sure to update
   // runtime/szrt_profiler.c as well.
   ProfileBlockInfoVarDecl->setName("__Sz_block_profile_info");
-  ProfileBlockInfoVarDecl->setSuppressMangling();
-  ProfileBlockInfoVarDecl->setLinkage(llvm::GlobalValue::ExternalLinkage);
 
   TargetLowering::staticInit(this);
 }
@@ -418,7 +415,7 @@ void GlobalContext::lowerGlobals(const IceString &SectionSuffix) {
     OstreamLocker L(this);
     Ostream &Stream = getStrDump();
     for (const Ice::VariableDeclaration *Global : Globals) {
-      Global->dump(this, Stream);
+      Global->dump(Stream);
     }
   }
   if (Flags.getDisableTranslation())
@@ -545,15 +542,15 @@ void GlobalContext::emitItems() {
 
         std::unique_ptr<Assembler> Asm = Item->getAsm();
         Asm->alignFunction();
-        IceString MangledName = mangleName(Asm->getFunctionName());
+        const IceString &Name = Asm->getFunctionName();
         switch (getFlags().getOutFileType()) {
         case FT_Elf:
-          getObjectWriter()->writeFunctionCode(MangledName, Asm->getInternal(),
+          getObjectWriter()->writeFunctionCode(Name, Asm->getInternal(),
                                                Asm.get());
           break;
         case FT_Iasm: {
           OstreamLocker L(this);
-          Cfg::emitTextHeader(MangledName, this, Asm.get());
+          Cfg::emitTextHeader(Name, this, Asm.get());
           Asm->emitIASBytes(this);
         } break;
         case FT_Asm:
@@ -587,169 +584,6 @@ void GlobalContext::emitItems() {
   lowerGlobalsIfNoCodeHasBeenSeen();
 }
 
-// Scan a string for S[0-9A-Z]*_ patterns and replace them with
-// S<num>_ where <num> is the next base-36 value.  If a type name
-// legitimately contains that pattern, then the substitution will be
-// made in error and most likely the link will fail.  In this case,
-// the test classes can be rewritten not to use that pattern, which is
-// much simpler and more reliable than implementing a full demangling
-// parser.  Another substitution-in-error may occur if a type
-// identifier ends with the pattern S[0-9A-Z]*, because an immediately
-// following substitution string like "S1_" or "PS1_" may be combined
-// with the previous type.
-void GlobalContext::incrementSubstitutions(ManglerVector &OldName) const {
-  const std::locale CLocale("C");
-  // Provide extra space in case the length of <num> increases.
-  ManglerVector NewName(OldName.size() * 2);
-  size_t OldPos = 0;
-  size_t NewPos = 0;
-  size_t OldLen = OldName.size();
-  for (; OldPos < OldLen; ++OldPos, ++NewPos) {
-    if (OldName[OldPos] == '\0')
-      break;
-    if (OldName[OldPos] == 'S') {
-      // Search forward until we find _ or invalid character (including \0).
-      bool AllZs = true;
-      bool Found = false;
-      size_t Last;
-      for (Last = OldPos + 1; Last < OldLen; ++Last) {
-        char Ch = OldName[Last];
-        if (Ch == '_') {
-          Found = true;
-          break;
-        } else if (std::isdigit(Ch) || std::isupper(Ch, CLocale)) {
-          if (Ch != 'Z')
-            AllZs = false;
-        } else {
-          // Invalid character, stop searching.
-          break;
-        }
-      }
-      if (Found) {
-        NewName[NewPos++] = OldName[OldPos++]; // 'S'
-        size_t Length = Last - OldPos;
-        // NewPos and OldPos point just past the 'S'.
-        assert(NewName[NewPos - 1] == 'S');
-        assert(OldName[OldPos - 1] == 'S');
-        assert(OldName[OldPos + Length] == '_');
-        if (AllZs) {
-          // Replace N 'Z' characters with a '0' (if N=0) or '1' (if N>0)
-          // followed by N '0' characters.
-          NewName[NewPos++] = (Length ? '1' : '0');
-          for (size_t i = 0; i < Length; ++i) {
-            NewName[NewPos++] = '0';
-          }
-        } else {
-          // Iterate right-to-left and increment the base-36 number.
-          bool Carry = true;
-          for (size_t i = 0; i < Length; ++i) {
-            size_t Offset = Length - 1 - i;
-            char Ch = OldName[OldPos + Offset];
-            if (Carry) {
-              Carry = false;
-              switch (Ch) {
-              case '9':
-                Ch = 'A';
-                break;
-              case 'Z':
-                Ch = '0';
-                Carry = true;
-                break;
-              default:
-                ++Ch;
-                break;
-              }
-            }
-            NewName[NewPos + Offset] = Ch;
-          }
-          NewPos += Length;
-        }
-        OldPos = Last;
-        // Fall through and let the '_' be copied across.
-      }
-    }
-    NewName[NewPos] = OldName[OldPos];
-  }
-  assert(NewName[NewPos] == '\0');
-  OldName = NewName;
-}
-
-// In this context, name mangling means to rewrite a symbol using a given
-// prefix. For a C++ symbol, nest the original symbol inside the "prefix"
-// namespace. For other symbols, just prepend the prefix.
-IceString GlobalContext::mangleName(const IceString &Name) const {
-  // An already-nested name like foo::bar() gets pushed down one level, making
-  // it equivalent to Prefix::foo::bar().
-  //   _ZN3foo3barExyz ==> _ZN6Prefix3foo3barExyz
-  // A non-nested but mangled name like bar() gets nested, making it equivalent
-  // to Prefix::bar().
-  //   _Z3barxyz ==> ZN6Prefix3barExyz
-  // An unmangled, extern "C" style name, gets a simple prefix:
-  //   bar ==> Prefixbar
-  if (!BuildDefs::dump() || getFlags().getTestPrefix().empty())
-    return Name;
-
-  const IceString &TestPrefix = getFlags().getTestPrefix();
-  unsigned PrefixLength = TestPrefix.length();
-  ManglerVector NameBase(1 + Name.length());
-  const size_t BufLen = 30 + Name.length() + PrefixLength;
-  ManglerVector NewName(BufLen);
-  uint32_t BaseLength = 0; // using uint32_t due to sscanf format string
-
-  int ItemsParsed = sscanf(Name.c_str(), "_ZN%s", NameBase.data());
-  if (ItemsParsed == 1) {
-    // Transform _ZN3foo3barExyz ==> _ZN6Prefix3foo3barExyz
-    //   (splice in "6Prefix")          ^^^^^^^
-    snprintf(NewName.data(), BufLen, "_ZN%u%s%s", PrefixLength,
-             TestPrefix.c_str(), NameBase.data());
-    // We ignore the snprintf return value (here and below). If we somehow
-    // miscalculated the output buffer length, the output will be truncated,
-    // but it will be truncated consistently for all mangleName() calls on the
-    // same input string.
-    incrementSubstitutions(NewName);
-    return NewName.data();
-  }
-
-  // Artificially limit BaseLength to 9 digits (less than 1 billion) because
-  // sscanf behavior is undefined on integer overflow. If there are more than 9
-  // digits (which we test by looking at the beginning of NameBase), then we
-  // consider this a failure to parse a namespace mangling, and fall back to
-  // the simple prefixing.
-  ItemsParsed = sscanf(Name.c_str(), "_Z%9u%s", &BaseLength, NameBase.data());
-  if (ItemsParsed == 2 && BaseLength <= strlen(NameBase.data()) &&
-      !isdigit(NameBase[0])) {
-    // Transform _Z3barxyz ==> _ZN6Prefix3barExyz
-    //                           ^^^^^^^^    ^
-    // (splice in "N6Prefix", and insert "E" after "3bar") But an "I" after the
-    // identifier indicates a template argument list terminated with "E";
-    // insert the new "E" before/after the old "E".  E.g.:
-    // Transform _Z3barIabcExyz ==> _ZN6Prefix3barIabcEExyz
-    //                                ^^^^^^^^         ^
-    // (splice in "N6Prefix", and insert "E" after "3barIabcE")
-    ManglerVector OrigName(Name.length());
-    ManglerVector OrigSuffix(Name.length());
-    uint32_t ActualBaseLength = BaseLength;
-    if (NameBase[ActualBaseLength] == 'I') {
-      ++ActualBaseLength;
-      while (NameBase[ActualBaseLength] != 'E' &&
-             NameBase[ActualBaseLength] != '\0')
-        ++ActualBaseLength;
-    }
-    strncpy(OrigName.data(), NameBase.data(), ActualBaseLength);
-    OrigName[ActualBaseLength] = '\0';
-    strcpy(OrigSuffix.data(), NameBase.data() + ActualBaseLength);
-    snprintf(NewName.data(), BufLen, "_ZN%u%s%u%sE%s", PrefixLength,
-             TestPrefix.c_str(), BaseLength, OrigName.data(),
-             OrigSuffix.data());
-    incrementSubstitutions(NewName);
-    return NewName.data();
-  }
-
-  // Transform bar ==> Prefixbar
-  //                   ^^^^^^
-  return TestPrefix + Name;
-}
-
 GlobalContext::~GlobalContext() {
   llvm::DeleteContainerPointers(AllThreadContexts);
   LockedPtr<DestructorArray> Dtors = getDestructors();
@@ -812,25 +646,21 @@ Constant *GlobalContext::getConstantDouble(double ConstantDouble) {
 Constant *GlobalContext::getConstantSym(const RelocOffsetT Offset,
                                         const RelocOffsetArray &OffsetExpr,
                                         const IceString &Name,
-                                        const IceString &EmitString,
-                                        bool SuppressMangling) {
+                                        const IceString &EmitString) {
   return getConstPool()->Relocatables.getOrAdd(
-      this,
-      RelocatableTuple(Offset, OffsetExpr, Name, EmitString, SuppressMangling));
+      this, RelocatableTuple(Offset, OffsetExpr, Name, EmitString));
 }
 
 Constant *GlobalContext::getConstantSym(RelocOffsetT Offset,
-                                        const IceString &Name,
-                                        bool SuppressMangling) {
+                                        const IceString &Name) {
   constexpr char EmptyEmitString[] = "";
-  return getConstantSym(Offset, {}, Name, EmptyEmitString, SuppressMangling);
+  return getConstantSym(Offset, {}, Name, EmptyEmitString);
 }
 
 Constant *GlobalContext::getConstantExternSym(const IceString &Name) {
   constexpr RelocOffsetT Offset = 0;
-  constexpr bool SuppressMangling = true;
   return getConstPool()->ExternRelocatables.getOrAdd(
-      this, RelocatableTuple(Offset, {}, Name, SuppressMangling));
+      this, RelocatableTuple(Offset, {}, Name));
 }
 
 Constant *GlobalContext::getConstantUndef(Type Ty) {
@@ -937,7 +767,7 @@ JumpTableDataList GlobalContext::getJumpTables() {
 }
 
 JumpTableData &
-GlobalContext::addJumpTable(IceString FuncName, SizeT Id,
+GlobalContext::addJumpTable(const IceString &FuncName, SizeT Id,
                             const JumpTableData::TargetList &TargetList) {
   auto JumpTableList = getJumpTableList();
   JumpTableList->emplace_back(FuncName, Id, TargetList);
@@ -1030,6 +860,9 @@ void GlobalContext::dumpTimers(TimerStackIdT StackID, bool DumpCumulative) {
   Timers->at(StackID).dump(getStrDump(), DumpCumulative);
 }
 
+ClFlags GlobalContext::Flags;
+ClFlagsExtra GlobalContext::ExtraFlags;
+
 void TimerMarker::push() {
   switch (StackID) {
   case GlobalContext::TSK_Default: