[llvm-commits] [llvm] r73720 - in /llvm/trunk: lib/CodeGen/AsmPrinter/AsmPrinter.cpp lib/Target/ARM/ARMTargetAsmInfo.cpp lib/Target/PowerPC/PPCTargetAsmInfo.cpp lib/Target/X86/X86TargetAsmInfo.cpp test/CodeGen/X86/pic_jumptable.ll

[Evan Cheng]

Author: evancheng
Date: Thu Jun 18 15:37:15 2009
New Revision: 73720

URL: http://llvm.org/viewvc/llvm-project?rev=73720&view=rev
Log:
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.

Modified:
    llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
    llvm/trunk/lib/Target/ARM/ARMTargetAsmInfo.cpp
    llvm/trunk/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
    llvm/trunk/lib/Target/X86/X86TargetAsmInfo.cpp
    llvm/trunk/test/CodeGen/X86/pic_jumptable.ll

Modified: llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp?rev=73720&r1=73719&r2=73720&view=diff

==============================================================================
--- llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp (original)
+++ llvm/trunk/lib/CodeGen/AsmPrinter/AsmPrinter.cpp Thu Jun 18 15:37:15 2009
@@ -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";

Modified: llvm/trunk/lib/Target/ARM/ARMTargetAsmInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/ARM/ARMTargetAsmInfo.cpp?rev=73720&r1=73719&r2=73720&view=diff

==============================================================================
--- llvm/trunk/lib/Target/ARM/ARMTargetAsmInfo.cpp (original)
+++ llvm/trunk/lib/Target/ARM/ARMTargetAsmInfo.cpp Thu Jun 18 15:37:15 2009
@@ -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";

Modified: llvm/trunk/lib/Target/PowerPC/PPCTargetAsmInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/PowerPC/PPCTargetAsmInfo.cpp?rev=73720&r1=73719&r2=73720&view=diff

==============================================================================
--- llvm/trunk/lib/Target/PowerPC/PPCTargetAsmInfo.cpp (original)
+++ llvm/trunk/lib/Target/PowerPC/PPCTargetAsmInfo.cpp Thu Jun 18 15:37:15 2009
@@ -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

Modified: llvm/trunk/lib/Target/X86/X86TargetAsmInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86TargetAsmInfo.cpp?rev=73720&r1=73719&r2=73720&view=diff

==============================================================================
--- llvm/trunk/lib/Target/X86/X86TargetAsmInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86TargetAsmInfo.cpp Thu Jun 18 15:37:15 2009
@@ -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;

Modified: llvm/trunk/test/CodeGen/X86/pic_jumptable.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/pic_jumptable.ll?rev=73720&r1=73719&r2=73720&view=diff

==============================================================================
--- llvm/trunk/test/CodeGen/X86/pic_jumptable.ll (original)
+++ llvm/trunk/test/CodeGen/X86/pic_jumptable.ll Thu Jun 18 15:37:15 2009
@@ -1,6 +1,8 @@
 ; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i386-linux-gnu -asm-verbose=false | not grep -F .text
 ; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i686-apple-darwin -asm-verbose=false | not grep lea
 ; RUN: llvm-as < %s | llc -relocation-model=pic -mtriple=i686-apple-darwin -asm-verbose=false | grep add | count 2
+; RUN: llvm-as < %s | llc                       -mtriple=x86_64-apple-darwin | not grep 'lJTI'
+; rdar://6971437
 
 declare void @_Z3bari(i32)