this is an initial patch to switch the ppc64 jit over to working in PIC mode,

which allows the code to be above the 2G marker.  We still need to JIT emit
dyld stubs to support external, weak, common, etc globals, but that will
happen tomorrow.

llvm-svn: 32348

1 files changed, 10 insertions, 2 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
index dde998f5a7f..9dcbc048700 100644
--- a/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
+++ b/llvm/lib/Target/PowerPC/PPCTargetMachine.cpp
@@ -135,9 +135,17 @@ bool PPCTargetMachine::addObjectWriter(FunctionPassManager &PM, bool Fast,
 
 bool PPCTargetMachine::addCodeEmitter(FunctionPassManager &PM, bool Fast,
                                       MachineCodeEmitter &MCE) {
-  // The JIT should use the static relocation model.
+  // The JIT should use the static relocation model in ppc32 mode, PIC in ppc64.
   // FIXME: This should be moved to TargetJITInfo!!
-  setRelocationModel(Reloc::Static);
+  if (Subtarget.isPPC64()) {
+    // We use PIC codegen in ppc64 mode, because otherwise we'd have to use many
+    // instructions to materialize arbitrary global variable + function +
+    // constant pool addresses.
+    setRelocationModel(Reloc::PIC_);
+  } else {
+    setRelocationModel(Reloc::Static);
+  }
+  
   
   // Machine code emitter pass for PowerPC.
   PM.add(createPPCCodeEmitterPass(*this, MCE));