Add getSymbolAlignment to the ObjectFile interface.

For regular object files this is only meaningful for common symbols. An object
file format with direct support for atoms should be able to provide alignment
information for all symbols.

This replaces getCommonSymbolAlignment and fixes
test-common-symbols-alignment.ll on darwin. This also includes a fix to
MachOObjectFile::getSymbolFlags. It was marking undefined symbols as common
(already tested by existing mcjit tests now that it is used).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180736 91177308-0d34-0410-b5e6-96231b3b80d8

10 files changed, 51 insertions, 21 deletions

diff --git a/include/llvm/Object/ELF.h b/include/llvm/Object/ELF.h
index 4f0e5b8db8..b36460ca52 100644
--- a/include/llvm/Object/ELF.h
+++ b/include/llvm/Object/ELF.h
@@ -682,6 +682,7 @@ protected:
   virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const;
   virtual error_code getSymbolFileOffset(DataRefImpl Symb, uint64_t &Res) const;
   virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const;
+  virtual error_code getSymbolAlignment(DataRefImpl Symb, uint32_t &Res) const;
   virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const;
   virtual error_code getSymbolNMTypeChar(DataRefImpl Symb, char &Res) const;
   virtual error_code getSymbolFlags(DataRefImpl Symb, uint32_t &Res) const;
@@ -1115,6 +1116,21 @@ error_code ELFObjectFile<ELFT>::getSymbolAddress(DataRefImpl Symb,
 }
 
 template<class ELFT>
+error_code ELFObjectFile<ELFT>::getSymbolAlignment(DataRefImpl Symb,
+                                                   uint32_t &Res) const {
+  uint32_t flags;
+  getSymbolFlags(Symb, flags);
+  if (flags & SymbolRef::SF_Common) {
+    uint64_t Value;
+    getSymbolValue(Symb, Value);
+    Res = Value;
+  } else {
+    Res = 0;
+  }
+  return object_error::success;
+}
+
+template<class ELFT>
 error_code ELFObjectFile<ELFT>::getSymbolSize(DataRefImpl Symb,
                                               uint64_t &Result) const {
   validateSymbol(Symb);
diff --git a/include/llvm/Object/MachO.h b/include/llvm/Object/MachO.h
index 98d3788e44..17a8fc2bff 100644
--- a/include/llvm/Object/MachO.h
+++ b/include/llvm/Object/MachO.h
@@ -39,6 +39,7 @@ public:
   virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const;
   virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const;
   virtual error_code getSymbolFileOffset(DataRefImpl Symb, uint64_t &Res) const;
+  virtual error_code getSymbolAlignment(DataRefImpl Symb, uint32_t &Res) const;
   virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const;
   virtual error_code getSymbolType(DataRefImpl Symb,
                                    SymbolRef::Type &Res) const;
diff --git a/include/llvm/Object/ObjectFile.h b/include/llvm/Object/ObjectFile.h
index cbe7ec92d3..eb53cc0aab 100644
--- a/include/llvm/Object/ObjectFile.h
+++ b/include/llvm/Object/ObjectFile.h
@@ -217,6 +217,8 @@ public:
   /// mapped).
   error_code getAddress(uint64_t &Result) const;
   error_code getFileOffset(uint64_t &Result) const;
+  /// @brief Get the alignment of this symbol as the actual value (not log 2).
+  error_code getAlignment(uint32_t &Result) const;
   error_code getSize(uint64_t &Result) const;
   error_code getType(SymbolRef::Type &Result) const;
 
@@ -292,6 +294,7 @@ protected:
   virtual error_code getSymbolName(DataRefImpl Symb, StringRef &Res) const = 0;
   virtual error_code getSymbolAddress(DataRefImpl Symb, uint64_t &Res) const = 0;
   virtual error_code getSymbolFileOffset(DataRefImpl Symb, uint64_t &Res)const=0;
+  virtual error_code getSymbolAlignment(DataRefImpl Symb, uint32_t &Res) const;
   virtual error_code getSymbolSize(DataRefImpl Symb, uint64_t &Res) const = 0;
   virtual error_code getSymbolType(DataRefImpl Symb,
                                    SymbolRef::Type &Res) const = 0;
@@ -425,6 +428,10 @@ inline error_code SymbolRef::getFileOffset(uint64_t &Result) const {
   return OwningObject->getSymbolFileOffset(SymbolPimpl, Result);
 }
 
+inline error_code SymbolRef::getAlignment(uint32_t &Result) const {
+  return OwningObject->getSymbolAlignment(SymbolPimpl, Result);
+}
+
 inline error_code SymbolRef::getSize(uint64_t &Result) const {
   return OwningObject->getSymbolSize(SymbolPimpl, Result);
 }
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
index 354795dc5f..7b32db7f0e 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp
@@ -96,7 +96,8 @@ ObjectImage *RuntimeDyldImpl::loadObject(ObjectBuffer *InputBuffer) {
     bool isCommon = flags & SymbolRef::SF_Common;
     if (isCommon) {
       // Add the common symbols to a list.  We'll allocate them all below.
-      uint64_t Align = getCommonSymbolAlignment(*i);
+      uint32_t Align;
+      Check(i->getAlignment(Align));
       uint64_t Size = 0;
       Check(i->getSize(Size));
       CommonSize += Size + Align;
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
index ef4a4050e9..c5bad8e416 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.cpp
@@ -848,13 +848,6 @@ void RuntimeDyldELF::processRelocationRef(unsigned SectionID,
   }
 }
 
-unsigned RuntimeDyldELF::getCommonSymbolAlignment(const SymbolRef &Sym) {
-  // In ELF, the value of an SHN_COMMON symbol is its alignment requirement.
-  uint64_t Align;
-  Check(Sym.getValue(Align));
-  return Align;
-}
-
 bool RuntimeDyldELF::isCompatibleFormat(const ObjectBuffer *Buffer) const {
   if (Buffer->getBufferSize() < strlen(ELF::ElfMagic))
     return false;
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
index b6ddf2d6a7..102b1c6b59 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldELF.h
@@ -68,9 +68,6 @@ class RuntimeDyldELF : public RuntimeDyldImpl {
                               int64_t Addend);
 
 
-  unsigned getCommonSymbolAlignment(const SymbolRef &Sym);
-
-
   uint64_t findPPC64TOC() const;
   void findOPDEntrySection(ObjectImage &Obj,
                            ObjSectionToIDMap &LocalSections,
diff --git a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
index 3211a1c7ea..51873b1f4b 100644
--- a/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
+++ b/lib/ExecutionEngine/RuntimeDyld/RuntimeDyldImpl.h
@@ -194,13 +194,6 @@ protected:
     return (uint8_t*)Sections[SectionID].Address;
   }
 
-  // Subclasses can override this method to get the alignment requirement of
-  // a common symbol. Returns no alignment requirement if not implemented.
-  virtual unsigned getCommonSymbolAlignment(const SymbolRef &Sym) {
-    return 0;
-  }
-
-
   void writeInt16BE(uint8_t *Addr, uint16_t Value) {
     if (sys::IsLittleEndianHost)
       Value = sys::SwapByteOrder(Value);
diff --git a/lib/Object/MachOObjectFile.cpp b/lib/Object/MachOObjectFile.cpp
index bb6ca93176..f6840b8c15 100644
--- a/lib/Object/MachOObjectFile.cpp
+++ b/lib/Object/MachOObjectFile.cpp
@@ -495,6 +495,19 @@ MachOObjectFile::getSymbolFileOffset(DataRefImpl Symb,
   return object_error::success;
 }
 
+error_code MachOObjectFile::getSymbolAlignment(DataRefImpl DRI,
+                                               uint32_t &Result) const {
+  uint32_t flags;
+  this->getSymbolFlags(DRI, flags);
+  if (flags & SymbolRef::SF_Common) {
+    SymbolTableEntryBase Entry = getSymbolTableEntryBase(this, DRI);
+    Result = 1 << MachO::GET_COMM_ALIGN(Entry.Flags);
+  } else {
+    Result = 0;
+  }
+  return object_error::success;
+}
+
 error_code MachOObjectFile::getSymbolSize(DataRefImpl DRI,
                                           uint64_t &Result) const {
   uint64_t BeginOffset;
@@ -609,8 +622,12 @@ error_code MachOObjectFile::getSymbolFlags(DataRefImpl DRI,
 
   if (MachOType & MachO::NlistMaskExternal) {
     Result |= SymbolRef::SF_Global;
-    if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined)
-      Result |= SymbolRef::SF_Common;
+    if ((MachOType & MachO::NlistMaskType) == MachO::NListTypeUndefined) {
+      uint64_t Value;
+      getSymbolAddress(DRI, Value);
+      if (Value)
+        Result |= SymbolRef::SF_Common;
+    }
   }
 
   if (MachOFlags & (MachO::NListDescWeakRef | MachO::NListDescWeakDef))
diff --git a/lib/Object/ObjectFile.cpp b/lib/Object/ObjectFile.cpp
index 518959aa05..77fd995cf0 100644
--- a/lib/Object/ObjectFile.cpp
+++ b/lib/Object/ObjectFile.cpp
@@ -27,6 +27,12 @@ ObjectFile::ObjectFile(unsigned int Type, MemoryBuffer *source)
   : Binary(Type, source) {
 }
 
+error_code ObjectFile::getSymbolAlignment(DataRefImpl DRI,
+                                          uint32_t &Result) const {
+  Result = 0;
+  return object_error::success;
+}
+
 ObjectFile *ObjectFile::createObjectFile(MemoryBuffer *Object) {
   if (!Object || Object->getBufferSize() < 64)
     return 0;
diff --git a/test/ExecutionEngine/MCJIT/test-common-symbols-alignment.ll b/test/ExecutionEngine/MCJIT/test-common-symbols-alignment.ll
index 43256c4492..989a473423 100644
--- a/test/ExecutionEngine/MCJIT/test-common-symbols-alignment.ll
+++ b/test/ExecutionEngine/MCJIT/test-common-symbols-alignment.ll
@@ -1,5 +1,4 @@
 ; RUN: %lli_mcjit -O0 %s
-; XFAIL: darwin
 
 ; This test checks that common symbols have been allocated addresses honouring
 ; the alignment requirement.