several major improvements to the sparc backend: support for weak linkage

and PIC codegen.  Patch by Venkatraman Govindaraju!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81877 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 19 insertions, 4 deletions

diff --git a/lib/Target/Sparc/SparcISelDAGToDAG.cpp b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
index e1b9b59b40..071590f4d7 100644
--- a/lib/Target/Sparc/SparcISelDAGToDAG.cpp
+++ b/lib/Target/Sparc/SparcISelDAGToDAG.cpp
@@ -34,10 +34,13 @@ class SparcDAGToDAGISel : public SelectionDAGISel {
   /// Subtarget - Keep a pointer to the Sparc Subtarget around so that we can
   /// make the right decision when generating code for different targets.
   const SparcSubtarget &Subtarget;
+  SparcTargetMachine& TM;
+  MachineBasicBlock *CurBB;
 public:
-  explicit SparcDAGToDAGISel(SparcTargetMachine &TM)
-    : SelectionDAGISel(TM),
-      Subtarget(TM.getSubtarget<SparcSubtarget>()) {
+  explicit SparcDAGToDAGISel(SparcTargetMachine &tm)
+    : SelectionDAGISel(tm),
+      Subtarget(tm.getSubtarget<SparcSubtarget>()),
+      TM(tm) {
   }
 
   SDNode *Select(SDValue Op);
@@ -63,6 +66,9 @@ public:
 
   // Include the pieces autogenerated from the target description.
 #include "SparcGenDAGISel.inc"
+
+private:
+  SDNode* getGlobalBaseReg();
 };
 }  // end anonymous namespace
 
@@ -70,12 +76,18 @@ public:
 /// SelectionDAGISel when it has created a SelectionDAG for us to codegen.
 void SparcDAGToDAGISel::InstructionSelect() {
   DEBUG(BB->dump());
-
+  CurBB = BB;
   // Select target instructions for the DAG.
   SelectRoot(*CurDAG);
   CurDAG->RemoveDeadNodes();
 }
 
+SDNode* SparcDAGToDAGISel::getGlobalBaseReg() {
+  MachineFunction *MF = CurBB->getParent();
+  unsigned GlobalBaseReg = TM.getInstrInfo()->getGlobalBaseReg(MF);
+  return CurDAG->getRegister(GlobalBaseReg, TLI.getPointerTy()).getNode();
+}
+
 bool SparcDAGToDAGISel::SelectADDRri(SDValue Op, SDValue Addr,
                                      SDValue &Base, SDValue &Offset) {
   if (FrameIndexSDNode *FIN = dyn_cast<FrameIndexSDNode>(Addr)) {
@@ -149,6 +161,9 @@ SDNode *SparcDAGToDAGISel::Select(SDValue Op) {
 
   switch (N->getOpcode()) {
   default: break;
+  case SPISD::GLOBAL_BASE_REG:
+    return getGlobalBaseReg();
+
   case ISD::SDIV:
   case ISD::UDIV: {
     // FIXME: should use a custom expander to expose the SRA to the dag.