commit a88b605721a602e473c6072b6d2bf20aec02b0c7
author Justin Hibbits <jrh29@alumni.cwru.edu> Wed Nov 12 15:16:30 2014 +0000
committer Justin Hibbits <jrh29@alumni.cwru.edu> Wed Nov 12 15:16:30 2014 +0000
tree 4839d0b50dc4a34a2721388b0216e852f3656b84
parent 62cf35b8a3116517017247b321d9c1dfbd94a401

Add support for small-model PIC for PowerPC.

Summary:
Large-model was added first.  With the addition of support for multiple PIC
models in LLVM, now add small-model PIC for 32-bit PowerPC, SysV4 ABI.  This
generates more optimal code, for shared libraries with less than about 16380
data objects.

Test Plan: Test cases added or updated

Reviewers: joerg, hfinkel

Reviewed By: hfinkel

Subscribers: jholewinski, mcrosier, emaste, llvm-commits

Differential Revision: http://reviews.llvm.org/D5399

llvm-svn: 221791

llvm/lib/Target/PowerPC/PPCISelLowering.cpp

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index 0c844be..17bf813 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -1689,6 +1689,8 @@
   const GlobalValue *GV = GA->getGlobal();
   EVT PtrVT = getPointerTy();
   bool is64bit = Subtarget.isPPC64();
+  const Module *M = DAG.getMachineFunction().getFunction()->getParent();
+  PICLevel::Level picLevel = M->getPICLevel();
 
   TLSModel::Model Model = getTargetMachine().getTLSModel(GV);
 
@@ -1728,7 +1730,10 @@
       GOTPtr = DAG.getNode(PPCISD::ADDIS_TLSGD_HA, dl, PtrVT,
                                    GOTReg, TGA);
     } else {
-      GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
+      if (picLevel == PICLevel::Small)
+        GOTPtr = DAG.getNode(PPCISD::GlobalBaseReg, dl, PtrVT);
+      else
+        GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
     }
     SDValue GOTEntry = DAG.getNode(PPCISD::ADDI_TLSGD_L, dl, PtrVT,
                                    GOTPtr, TGA);
@@ -1745,7 +1750,10 @@
       GOTPtr = DAG.getNode(PPCISD::ADDIS_TLSLD_HA, dl, PtrVT,
                            GOTReg, TGA);
     } else {
-      GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
+      if (picLevel == PICLevel::Small)
+        GOTPtr = DAG.getNode(PPCISD::GlobalBaseReg, dl, PtrVT);
+      else
+        GOTPtr = DAG.getNode(PPCISD::PPC32_PICGOT, dl, PtrVT);
     }
     SDValue GOTEntry = DAG.getNode(PPCISD::ADDI_TLSLD_L, dl, PtrVT,
                                    GOTPtr, TGA);