From: Hal Finkel <hfinkel@anl.gov>
Date: Thu, 6 Mar 2014 01:28:23 +0000 (+0000)
Subject: The PPC global base register cannot be r0
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=a14dc34e10c8a57d57f37b437e2e6221585ef958;p=oota-llvm.git

The PPC global base register cannot be r0

The global base register cannot be r0 because it might end up as the first
argument to addi or addis. Fixes PR18316.

I don't have a small stable test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@203054 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
index 44821d31b51..65ea49a8e2b 100644
--- a/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
+++ b/lib/Target/PowerPC/PPCISelDAGToDAG.cpp
@@ -272,11 +272,11 @@ SDNode *PPCDAGToDAGISel::getGlobalBaseReg() {
     DebugLoc dl;
 
     if (PPCLowering.getPointerTy() == MVT::i32) {
-      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::GPRCRegClass);
+      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::GPRC_NOR0RegClass);
       BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR));
       BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR), GlobalBaseReg);
     } else {
-      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::G8RCRegClass);
+      GlobalBaseReg = RegInfo->createVirtualRegister(&PPC::G8RC_NOX0RegClass);
       BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR8));
       BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR8), GlobalBaseReg);
     }