the latest assembler that runs on powerpc 10.4 machines doesn't

support aligned comm.  Detect when compiling for 10.4 and don't
emit an alignment for comm.  THis will hopefully fix PR8198.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114817 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 25 insertions, 2 deletions

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index ee6d321..0de2021 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -282,8 +282,12 @@ void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
     
     // Handle common symbols.
     if (GVKind.isCommon()) {
+      unsigned Align = 1 << AlignLog;
+      if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
+        Align = 0;
+          
       // .comm _foo, 42, 4
-      OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
+      OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
       return;
     }
     
@@ -301,11 +305,15 @@ void AsmPrinter::EmitGlobalVariable(const GlobalVariable *GV) {
       OutStreamer.EmitLocalCommonSymbol(GVSym, Size);
       return;
     }
+
+    unsigned Align = 1 << AlignLog;
+    if (!getObjFileLowering().getCommDirectiveSupportsAlignment())
+      Align = 0;
     
     // .local _foo
     OutStreamer.EmitSymbolAttribute(GVSym, MCSA_Local);
     // .comm _foo, 42, 4
-    OutStreamer.EmitCommonSymbol(GVSym, Size, 1 << AlignLog);
+    OutStreamer.EmitCommonSymbol(GVSym, Size, Align);
     return;
   }
   
diff --git a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
index f1e10ee..4afdc3d 100644
--- a/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
+++ b/lib/CodeGen/TargetLoweringObjectFileImpl.cpp
@@ -33,6 +33,7 @@
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/ADT/SmallString.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/Triple.h"
 using namespace llvm;
 using namespace dwarf;
 
@@ -450,6 +451,19 @@ void TargetLoweringObjectFileMachO::Initialize(MCContext &Ctx,
   IsFunctionEHSymbolGlobal = true;
   IsFunctionEHFrameSymbolPrivate = false;
   SupportsWeakOmittedEHFrame = false;
+
+  Triple T(((LLVMTargetMachine&)TM).getTargetTriple());
+  if (T.getOS() == Triple::Darwin) {
+    switch (T.getDarwinMajorNumber()) {
+    case 7:  // 10.3 Panther.
+    case 8:  // 10.4 Tiger.
+      CommDirectiveSupportsAlignment = false;
+      break;
+    case 9:   // 10.5 Leopard.
+    case 10:  // 10.6 SnowLeopard.
+      break;
+    }
+  }
   
   TargetLoweringObjectFile::Initialize(Ctx, TM);
 
diff --git a/lib/Target/TargetLoweringObjectFile.cpp b/lib/Target/TargetLoweringObjectFile.cpp
index dd7b532..0e67fe5 100644
--- a/lib/Target/TargetLoweringObjectFile.cpp
+++ b/lib/Target/TargetLoweringObjectFile.cpp
@@ -45,6 +45,7 @@ TargetLoweringObjectFile::TargetLoweringObjectFile() : Ctx(0) {
   LSDASection = 0;
   EHFrameSection = 0;
 
+  CommDirectiveSupportsAlignment = true;
   DwarfAbbrevSection = 0;
   DwarfInfoSection = 0;
   DwarfLineSection = 0;