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.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73720 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 15511c4..7ab775e 100644
--- a/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -347,8 +347,9 @@
   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 @@
     SwitchToSection(TAI->SectionForGlobal(F));
   } else {
     SwitchToDataSection(JumpTableDataSection);
+    JTInDiffSection = true;
   }
   
   EmitAlignment(Log2_32(MJTI->getAlignment()));
@@ -380,8 +382,10 @@
     // 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";
diff --git a/lib/Target/ARM/ARMTargetAsmInfo.cpp b/lib/Target/ARM/ARMTargetAsmInfo.cpp
index 4107dcc..a441968 100644
--- a/lib/Target/ARM/ARMTargetAsmInfo.cpp
+++ b/lib/Target/ARM/ARMTargetAsmInfo.cpp
@@ -74,10 +74,10 @@
 
   // In non-PIC modes, emit a special label before jump tables so that the
   // linker can perform more accurate dead code stripping.
-  if (TM.getRelocationModel() != Reloc::PIC_) {
-    // Emit a local label that is preserved until the linker runs.
-    JumpTableSpecialLabelPrefix = "l";
-  }
+  // Emit a local label that is preserved until the linker runs.
+  // We do not check the relocation model here since it can be overridden
+  // later.
+  JumpTableSpecialLabelPrefix = "l";
 
   NeedsSet = true;
   DwarfAbbrevSection = ".section __DWARF,__debug_abbrev,regular,debug";
diff --git a/lib/Target/PowerPC/PPCTargetAsmInfo.cpp b/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
index c69e591..c8d1132 100644
--- a/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
+++ b/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
@@ -68,10 +68,9 @@
   
   // In non-PIC modes, emit a special label before jump tables so that the
   // linker can perform more accurate dead code stripping.
-  if (TM.getRelocationModel() != Reloc::PIC_) {
-    // Emit a local label that is preserved until the linker runs.
-    JumpTableSpecialLabelPrefix = "l";
-  }
+  // We do not check the relocation model here since it can be overridden
+  // later.
+  JumpTableSpecialLabelPrefix = "l";
 }
 
 /// PreferredEHDataFormat - This hook allows the target to select data
diff --git a/lib/Target/X86/X86TargetAsmInfo.cpp b/lib/Target/X86/X86TargetAsmInfo.cpp
index 5dda5f4..0c474e1 100644
--- a/lib/Target/X86/X86TargetAsmInfo.cpp
+++ b/lib/Target/X86/X86TargetAsmInfo.cpp
@@ -99,10 +99,10 @@
 
   // In non-PIC modes, emit a special label before jump tables so that the
   // linker can perform more accurate dead code stripping.
-  if (TM.getRelocationModel() != Reloc::PIC_) {
-    // Emit a local label that is preserved until the linker runs.
-    JumpTableSpecialLabelPrefix = "l";
-  }
+  // Emit a local label that is preserved until the linker runs.
+  // We do not check the relocation model here since it can be overridden
+  // later.
+  JumpTableSpecialLabelPrefix = "l";
 
   SupportsDebugInformation = true;
   NeedsSet = true;