[PM/AA] Hoist ScopedNoAliasAA's interface into a header and move the

[oota-llvm.git] / lib / CodeGen / TargetFrameLoweringImpl.cpp

diff --git a/lib/CodeGen/TargetFrameLoweringImpl.cpp b/lib/CodeGen/TargetFrameLoweringImpl.cpp
index e3f01912b872a51fe11d41071a7f7fd49777741b..f3cccd82a5c57a700ebb8f4d99c10dcbd3db4581 100644 (file)
--- a/lib/CodeGen/TargetFrameLoweringImpl.cpp
+++ b/lib/CodeGen/TargetFrameLoweringImpl.cpp
@@ -11,9 +11,13 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/ADT/BitVector.h"
 #include "llvm/Target/TargetFrameLowering.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/IR/Function.h"
 #include "llvm/Target/TargetRegisterInfo.h"
 #include "llvm/Target/TargetSubtargetInfo.h"
 #include <cstdlib>
@@ -22,6 +26,12 @@ using namespace llvm;
 TargetFrameLowering::~TargetFrameLowering() {
 }
 
+/// The default implementation just looks at attribute "no-frame-pointer-elim".
+bool TargetFrameLowering::noFramePointerElim(const MachineFunction &MF) const {
+  auto Attr = MF.getFunction()->getFnAttribute("no-frame-pointer-elim");
+  return Attr.getValueAsString() == "true";
+}
+
 /// getFrameIndexOffset - Returns the displacement from the frame register to
 /// the stack frame of the specified index. This is the default implementation
 /// which is overridden for some targets.
@@ -47,3 +57,30 @@ bool TargetFrameLowering::needsFrameIndexResolution(
     const MachineFunction &MF) const {
   return MF.getFrameInfo()->hasStackObjects();
 }
+
+void TargetFrameLowering::determineCalleeSaves(MachineFunction &MF,
+                                               BitVector &SavedRegs,
+                                               RegScavenger *RS) const {
+  // Get the callee saved register list...
+  const TargetRegisterInfo &TRI = *MF.getSubtarget().getRegisterInfo();
+  const MCPhysReg *CSRegs = TRI.getCalleeSavedRegs(&MF);
+
+  // Early exit if there are no callee saved registers.
+  if (!CSRegs || CSRegs[0] == 0)
+    return;
+
+  SavedRegs.resize(TRI.getNumRegs());
+
+  // In Naked functions we aren't going to save any registers.
+  if (MF.getFunction()->hasFnAttribute(Attribute::Naked))
+    return;
+
+  // Functions which call __builtin_unwind_init get all their registers saved.
+  bool CallsUnwindInit = MF.getMMI().callsUnwindInit();
+  const MachineRegisterInfo &MRI = MF.getRegInfo();
+  for (unsigned i = 0; CSRegs[i]; ++i) {
+    unsigned Reg = CSRegs[i];
+    if (CallsUnwindInit || MRI.isPhysRegModified(Reg))
+      SavedRegs.set(Reg);
+  }
+}