[Sparc] Implements hasReservedCallFrame and hasFP.

 This is to generate correct framesetup code when the function
 has variable sized allocas.

llvm-svn: 182108

2 files changed, 17 insertions, 1 deletions

diff --git a/llvm/lib/Target/Sparc/SparcFrameLowering.cpp b/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
index 7874240f598..afa8411802d 100644
--- a/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
+++ b/llvm/lib/Target/Sparc/SparcFrameLowering.cpp
@@ -106,3 +106,18 @@ void SparcFrameLowering::emitEpilogue(MachineFunction &MF,
   BuildMI(MBB, MBBI, dl, TII.get(SP::RESTORErr), SP::G0).addReg(SP::G0)
     .addReg(SP::G0);
 }
+
+bool SparcFrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
+  //Reserve call frame if there are no variable sized objects on the stack
+  return !MF.getFrameInfo()->hasVarSizedObjects();
+}
+
+// hasFP - Return true if the specified function should have a dedicated frame
+// pointer register.  This is true if the function has variable sized allocas or
+// if frame pointer elimination is disabled.
+bool SparcFrameLowering::hasFP(const MachineFunction &MF) const {
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  return MF.getTarget().Options.DisableFramePointerElim(MF) ||
+    MFI->hasVarSizedObjects() || MFI->isFrameAddressTaken();
+}
+
diff --git a/llvm/lib/Target/Sparc/SparcFrameLowering.h b/llvm/lib/Target/Sparc/SparcFrameLowering.h
index c3756620161..4a3cef703ff 100644
--- a/llvm/lib/Target/Sparc/SparcFrameLowering.h
+++ b/llvm/lib/Target/Sparc/SparcFrameLowering.h
@@ -38,7 +38,8 @@ public:
                                      MachineBasicBlock &MBB,
                                      MachineBasicBlock::iterator I) const;
 
-  bool hasFP(const MachineFunction &MF) const { return false; }
+  bool hasReservedCallFrame(const MachineFunction &MF) const;
+  bool hasFP(const MachineFunction &MF) const;
 };
 
 } // End llvm namespace