From: Chris Lattner <sabre@nondot.org>
Date: Mon, 20 Nov 2006 20:48:05 +0000 (+0000)
Subject: in ppc64-mode, don't allocate the 32-bit version of r13 either.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=e9c9f98f719cc597444181cd6634fac247f8f68c;p=oota-llvm.git

in ppc64-mode, don't allocate the 32-bit version of r13 either.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@31884 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/PowerPC/PPCRegisterInfo.td b/lib/Target/PowerPC/PPCRegisterInfo.td
index 6c18e17eebb..51000f9a080 100644
--- a/lib/Target/PowerPC/PPCRegisterInfo.td
+++ b/lib/Target/PowerPC/PPCRegisterInfo.td
@@ -224,6 +224,12 @@ def GPRC : RegisterClass<"PPC", [i32], 32,
     }
     GPRCClass::iterator
     GPRCClass::allocation_order_end(const MachineFunction &MF) const {
+      // On PPC64, r13 is the thread pointer.  Never allocate this register.
+      // Note that this is overconservative, as it also prevents allocation of
+      // R31 when the FP is not needed.
+      if (MF.getTarget().getSubtarget<PPCSubtarget>().isPPC64())
+        return end()-5;  // don't allocate R13, R31, R0, R1, LR
+        
       if (needsFP(MF))
         return end()-4;  // don't allocate R31, R0, R1, LR
       else