Lower constant pools and jump tables via TOC on PPC64/SVR4.

In collaboration with Adhemerval Zanella.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162562 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 61d44c5..c18ba69 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -1204,6 +1204,14 @@
   ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
   const Constant *C = CP->getConstVal();
 
+  // 64-bit SVR4 ABI code is always position-independent.
+  // The actual address of the GlobalValue is stored in the TOC.
+  if (PPCSubTarget.isSVR4ABI() && PPCSubTarget.isPPC64()) {
+    SDValue GA = DAG.getTargetConstantPool(C, PtrVT, CP->getAlignment(), 0);
+    return DAG.getNode(PPCISD::TOC_ENTRY, CP->getDebugLoc(), MVT::i64, GA,
+                       DAG.getRegister(PPC::X2, MVT::i64));
+  }
+
   unsigned MOHiFlag, MOLoFlag;
   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag);
   SDValue CPIHi =
@@ -1217,6 +1225,14 @@
   EVT PtrVT = Op.getValueType();
   JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
 
+  // 64-bit SVR4 ABI code is always position-independent.
+  // The actual address of the GlobalValue is stored in the TOC.
+  if (PPCSubTarget.isSVR4ABI() && PPCSubTarget.isPPC64()) {
+    SDValue GA = DAG.getTargetJumpTable(JT->getIndex(), PtrVT);
+    return DAG.getNode(PPCISD::TOC_ENTRY, JT->getDebugLoc(), MVT::i64, GA,
+                       DAG.getRegister(PPC::X2, MVT::i64));
+  }
+
   unsigned MOHiFlag, MOLoFlag;
   bool isPIC = GetLabelAccessInfo(DAG.getTarget(), MOHiFlag, MOLoFlag);
   SDValue JTIHi = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MOHiFlag);