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

diff --git a/include/llvm/Target/TargetLoweringObjectFile.h b/include/llvm/Target/TargetLoweringObjectFile.h
index 819709fa20c20488cfbb28e16b2a516e1165c3c5..5456dd07003377c60a12a26ae4a15f5431798747 100644 (file)
--- a/include/llvm/Target/TargetLoweringObjectFile.h
+++ b/include/llvm/Target/TargetLoweringObjectFile.h
@@ -92,6 +92,11 @@ protected:
   // information for a TLS variable, it'll go here.
   const MCSection *TLSExtraDataSection;
   
+  /// CommDirectiveSupportsAlignment - True if .comm supports alignment.  This
+  /// is a hack for as long as we support 10.4 Tiger, whose assembler doesn't
+  /// support alignment on comm.
+  bool CommDirectiveSupportsAlignment;
+  
   /// SupportsWeakEmptyEHFrame - True if target object file supports a
   /// weak_definition of constant 0 for an omitted EH frame.
   bool SupportsWeakOmittedEHFrame;
@@ -128,6 +133,10 @@ public:
     return SupportsWeakOmittedEHFrame;
   }
   
+  bool getCommDirectiveSupportsAlignment() const {
+    return CommDirectiveSupportsAlignment;
+  }
+
   const MCSection *getTextSection() const { return TextSection; }
   const MCSection *getDataSection() const { return DataSection; }
   const MCSection *getBSSSection() const { return BSSSection; }

diff --git a/include/llvm/Target/TargetMachine.h b/include/llvm/Target/TargetMachine.h
index 426338ff8d47d13ed19f72ce11d629fa5acb4bfc..35f2658acd90da0a1da793faaf2c5a3f683ceb39 100644 (file)
--- a/include/llvm/Target/TargetMachine.h
+++ b/include/llvm/Target/TargetMachine.h
@@ -280,6 +280,8 @@ private:
   
 public:
   
+  const std::string &getTargetTriple() const { return TargetTriple; }
+  
   /// addPassesToEmitFile - Add passes to the specified pass manager to get the
   /// specified file emitted.  Typically this will involve several steps of code
   /// generation.  If OptLevel is None, the code generator should emit code as

diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index ee6d321763ab227aa27d7499ae4d2f481830c5ad..0de2021133677dc5384c3e6ccbf506a3bd591f31 100644 (file)
--- 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 f1e10eec724c66e1a28a068c951aadb6ae3e2970..4afdc3ddef522a33be4d5da9261136657103d17b 100644 (file)
--- 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 dd7b532bbfbaef701376d24ce1aea43711b8ea63..0e67fe5d9877be59ef67df74e44bb328bfdaacef 100644 (file)
--- 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;

diff --git a/test/CodeGen/PowerPC/align.ll b/test/CodeGen/PowerPC/align.ll
index 109a83726e98f73bc80f66788a584ab92b2bd3c6..0797ca8d0be8948e20a2d17c3f0b39290371d0fe 100644 (file)
--- a/test/CodeGen/PowerPC/align.ll
+++ b/test/CodeGen/PowerPC/align.ll
@@ -1,5 +1,6 @@
 ; RUN: llc < %s -mtriple=powerpc-linux-gnu | FileCheck %s -check-prefix=ELF
 ; RUN: llc < %s -mtriple=powerpc-apple-darwin9 | FileCheck %s -check-prefix=DARWIN
+; RUN: llc < %s -mtriple=powerpc-apple-darwin8 | FileCheck %s -check-prefix=DARWIN8
 
 @a = global i1 true
 ; no alignment
@@ -40,3 +41,6 @@
 @bar = common global [75 x i8] zeroinitializer, align 128
 ;ELF: .comm bar,75,128
 ;DARWIN: .comm _bar,75,7
+
+;; Darwin8 doesn't support aligned comm.  Just miscompile this.
+; DARWIN8: .comm _bar,75 ;