On Darwin, ams printer should output a second label before a jump table so the linker knows it's a new atom. But this is only needed if the jump table is put in a separate section from the function body.

llvm-svn: 73720

1 files changed, 7 insertions, 3 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 15511c4615b..7ab775e26a4 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -347,8 +347,9 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
   const char* JumpTableDataSection = TAI->getJumpTableDataSection();
   const Function *F = MF.getFunction();
   unsigned SectionFlags = TAI->SectionFlagsForGlobal(F);
+  bool JTInDiffSection = false;
   if ((IsPic && !(LoweringInfo && LoweringInfo->usesGlobalOffsetTable())) ||
-     !JumpTableDataSection ||
+      !JumpTableDataSection ||
       SectionFlags & SectionFlags::Linkonce) {
     // In PIC mode, we need to emit the jump table to the same section as the
     // function body itself, otherwise the label differences won't make sense.
@@ -357,6 +358,7 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
     SwitchToSection(TAI->SectionForGlobal(F));
   } else {
     SwitchToDataSection(JumpTableDataSection);
+    JTInDiffSection = true;
   }
   
   EmitAlignment(Log2_32(MJTI->getAlignment()));
@@ -380,8 +382,10 @@ void AsmPrinter::EmitJumpTableInfo(MachineJumpTableInfo *MJTI,
     // before each jump table.  The first label is never referenced, but tells
     // the assembler and linker the extents of the jump table object.  The
     // second label is actually referenced by the code.
-    if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
-      O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
+    if (JTInDiffSection) {
+      if (const char *JTLabelPrefix = TAI->getJumpTableSpecialLabelPrefix())
+        O << JTLabelPrefix << "JTI" << getFunctionNumber() << '_' << i << ":\n";
+    }
     
     O << TAI->getPrivateGlobalPrefix() << "JTI" << getFunctionNumber() 
       << '_' << i << ":\n";