X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FTargetFrameLoweringImpl.cpp;h=679ade185e1c69cfbd700282507133af37f91b7e;hb=813f44a29fd0fd140127023222d0633e23783bcc;hp=cadb87815dbe1f11a50266b503f0cd32867cf542;hpb=028700f544deeea423ce9b516e190e4e970e3c6c;p=oota-llvm.git

diff --git a/lib/CodeGen/TargetFrameLoweringImpl.cpp b/lib/CodeGen/TargetFrameLoweringImpl.cpp
index cadb87815db..679ade185e1 100644
--- a/lib/CodeGen/TargetFrameLoweringImpl.cpp
+++ b/lib/CodeGen/TargetFrameLoweringImpl.cpp
@@ -11,35 +11,84 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/ADT/BitVector.h"
+#include "llvm/Target/TargetFrameLowering.h"
 #include "llvm/CodeGen/MachineFrameInfo.h"
 #include "llvm/CodeGen/MachineFunction.h"
-#include "llvm/Target/TargetFrameLowering.h"
-#include "llvm/Target/TargetMachine.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/IR/CallingConv.h"
+#include "llvm/IR/Function.h"
 #include "llvm/Target/TargetRegisterInfo.h"
-
+#include "llvm/Target/TargetSubtargetInfo.h"
 #include <cstdlib>
 using namespace llvm;
 
 TargetFrameLowering::~TargetFrameLowering() {
 }
 
-/// 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.
-int TargetFrameLowering::getFrameIndexOffset(const MachineFunction &MF,
-                                         int FI) const {
-  const MachineFrameInfo *MFI = MF.getFrameInfo();
-  return MFI->getObjectOffset(FI) + MFI->getStackSize() -
-    getOffsetOfLocalArea() + MFI->getOffsetAdjustment();
+/// 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";
 }
 
+/// Returns the displacement from the frame register to the stack
+/// frame of the specified index, along with the frame register used
+/// (in output arg FrameReg). This is the default implementation which
+/// is overridden for some targets.
 int TargetFrameLowering::getFrameIndexReference(const MachineFunction &MF,
                                              int FI, unsigned &FrameReg) const {
-  const TargetRegisterInfo *RI = MF.getTarget().getRegisterInfo();
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  const TargetRegisterInfo *RI = MF.getSubtarget().getRegisterInfo();
 
   // By default, assume all frame indices are referenced via whatever
   // getFrameRegister() says. The target can override this if it's doing
   // something different.
   FrameReg = RI->getFrameRegister(MF);
-  return getFrameIndexOffset(MF, FI);
+
+  return MFI->getObjectOffset(FI) + MFI->getStackSize() -
+         getOffsetOfLocalArea() + MFI->getOffsetAdjustment();
+}
+
+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);
+  }
+}
+
+unsigned TargetFrameLowering::getStackAlignmentSkew(
+    const MachineFunction &MF) const {
+  // When HHVM function is called, the stack is skewed as the return address
+  // is removed from the stack before we enter the function.
+  if (LLVM_UNLIKELY(MF.getFunction()->getCallingConv() == CallingConv::HHVM))
+    return MF.getTarget().getPointerSize();
+
+  return 0;
 }