[llvm-commits] CVS: llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp PPCRegisterInfo.h

[Evan Cheng]

Changes in directory llvm/lib/Target/PowerPC:

PPCRegisterInfo.cpp updated: 1.105 -> 1.106
PPCRegisterInfo.h updated: 1.24 -> 1.25
---
Log message:

Added getReservedRegs().

---
Diffs of the changes:  (+32 -9)

 PPCRegisterInfo.cpp |   39 ++++++++++++++++++++++++++++++---------
 PPCRegisterInfo.h   |    2 ++
 2 files changed, 32 insertions(+), 9 deletions(-)


Index: llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp
diff -u llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.105 llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.106
--- llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.105	Thu Feb  1 10:31:34 2007
+++ llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp	Sat Feb 17 05:06:00 2007
@@ -34,6 +34,7 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/MathExtras.h"
+#include "llvm/ADT/BitVector.h"
 #include "llvm/ADT/STLExtras.h"
 #include <cstdlib>
 using namespace llvm;
@@ -338,6 +339,35 @@
                                Darwin32_CalleeSavedRegClasses;
 }
 
+// needsFP - 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.
+//
+static bool needsFP(const MachineFunction &MF) {
+  const MachineFrameInfo *MFI = MF.getFrameInfo();
+  return NoFramePointerElim || MFI->hasVarSizedObjects();
+}
+
+BitVector PPCRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
+  BitVector Reserved(getNumRegs());
+  Reserved.set(PPC::R0);
+  Reserved.set(PPC::R1);
+  Reserved.set(PPC::LR);
+  // In Linux, r2 is reserved for the OS.
+  if (!Subtarget.isDarwin())
+    Reserved.set(PPC::R2);
+  // 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 (Subtarget.isPPC64()) {
+    Reserved.set(PPC::R13);
+    Reserved.set(PPC::R31);
+  }
+  if (needsFP(MF))
+    Reserved.set(PPC::R31);
+  return Reserved;
+}
+
 /// foldMemoryOperand - PowerPC (like most RISC's) can only fold spills into
 /// copy instructions, turning them into load/store instructions.
 MachineInstr *PPCRegisterInfo::foldMemoryOperand(MachineInstr *MI,
@@ -398,15 +428,6 @@
 // Stack Frame Processing methods
 //===----------------------------------------------------------------------===//
 
-// needsFP - 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.
-//
-static bool needsFP(const MachineFunction &MF) {
-  const MachineFrameInfo *MFI = MF.getFrameInfo();
-  return NoFramePointerElim || MFI->hasVarSizedObjects();
-}
-
 // hasFP - Return true if the specified function actually has a dedicated frame
 // pointer register.  This is true if the function needs a frame pointer and has
 // a non-zero stack size.


Index: llvm/lib/Target/PowerPC/PPCRegisterInfo.h
diff -u llvm/lib/Target/PowerPC/PPCRegisterInfo.h:1.24 llvm/lib/Target/PowerPC/PPCRegisterInfo.h:1.25
--- llvm/lib/Target/PowerPC/PPCRegisterInfo.h:1.24	Thu Jan 25 16:25:04 2007
+++ llvm/lib/Target/PowerPC/PPCRegisterInfo.h	Sat Feb 17 05:06:00 2007
@@ -58,6 +58,8 @@
 
   const TargetRegisterClass* const* getCalleeSavedRegClasses() const;
 
+  BitVector getReservedRegs(const MachineFunction &MF) const;
+
   /// targetHandlesStackFrameRounding - Returns true if the target is
   /// responsible for rounding up the stack frame (probably at emitPrologue
   /// time).