Move hasFP() and few related hooks to TargetFrameInfo.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119740 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 26 insertions, 0 deletions

diff --git a/include/llvm/Target/TargetFrameInfo.h b/include/llvm/Target/TargetFrameInfo.h
index 6143f3c549..d8d0ca1edd 100644
--- a/include/llvm/Target/TargetFrameInfo.h
+++ b/include/llvm/Target/TargetFrameInfo.h
@@ -105,6 +105,32 @@ public:
   virtual void emitPrologue(MachineFunction &MF) const = 0;
   virtual void emitEpilogue(MachineFunction &MF,
                             MachineBasicBlock &MBB) const = 0;
+
+  /// hasFP - Return true if the specified function should have a dedicated
+  /// frame pointer register. For most targets this is true only if the function
+  /// has variable sized allocas or if frame pointer elimination is disabled.
+  virtual bool hasFP(const MachineFunction &MF) const = 0;
+
+  /// hasReservedCallFrame - Under normal circumstances, when a frame pointer is
+  /// not required, we reserve argument space for call sites in the function
+  /// immediately on entry to the current function. This eliminates the need for
+  /// add/sub sp brackets around call sites. Returns true if the call frame is
+  /// included as part of the stack frame.
+  virtual bool hasReservedCallFrame(const MachineFunction &MF) const {
+    return !hasFP(MF);
+  }
+
+  /// canSimplifyCallFramePseudos - When possible, it's best to simplify the
+  /// call frame pseudo ops before doing frame index elimination. This is
+  /// possible only when frame index references between the pseudos won't
+  /// need adjusting for the call frame adjustments. Normally, that's true
+  /// if the function has a reserved call frame or a frame pointer. Some
+  /// targets (Thumb2, for example) may have more complicated criteria,
+  /// however, and can override this behavior.
+  virtual bool canSimplifyCallFramePseudos(const MachineFunction &MF) const {
+    return hasReservedCallFrame(MF) || hasFP(MF);
+  }
+
 };
 
 } // End llvm namespace