[llvm] r185525 - [SystemZ] Fix caller-allocated save slot FIXME
Richard Sandiford
rsandifo at linux.vnet.ibm.com
Wed Jul 3 02:11:01 PDT 2013
Author: rsandifo
Date: Wed Jul 3 04:11:00 2013
New Revision: 185525
URL: http://llvm.org/viewvc/llvm-project?rev=185525&view=rev
Log:
[SystemZ] Fix caller-allocated save slot FIXME
Get rid of some old code (and associated FIXME) for handling the
caller-allocated register save area. No behavioural change intended.
Modified:
llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.cpp
llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.h
llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
Modified: llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.cpp?rev=185525&r1=185524&r2=185525&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.cpp (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.cpp Wed Jul 3 04:11:00 2013
@@ -18,15 +18,10 @@
using namespace llvm;
-SystemZFrameLowering::SystemZFrameLowering(const SystemZTargetMachine &tm,
- const SystemZSubtarget &sti)
- : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 8,
- -SystemZMC::CallFrameSize),
- TM(tm),
- STI(sti) {
+namespace {
// The ABI-defined register save slots, relative to the incoming stack
// pointer.
- static const unsigned SpillOffsetTable[][2] = {
+ static const TargetFrameLowering::SpillSlot SpillOffsetTable[] = {
{ SystemZ::R2D, 0x10 },
{ SystemZ::R3D, 0x18 },
{ SystemZ::R4D, 0x20 },
@@ -46,11 +41,23 @@ SystemZFrameLowering::SystemZFrameLoweri
{ SystemZ::F4D, 0x90 },
{ SystemZ::F6D, 0x98 }
};
+}
+SystemZFrameLowering::SystemZFrameLowering(const SystemZTargetMachine &tm,
+ const SystemZSubtarget &sti)
+ : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 8,
+ -SystemZMC::CallFrameSize, 8),
+ TM(tm), STI(sti) {
// Create a mapping from register number to save slot offset.
RegSpillOffsets.grow(SystemZ::NUM_TARGET_REGS);
for (unsigned I = 0, E = array_lengthof(SpillOffsetTable); I != E; ++I)
- RegSpillOffsets[SpillOffsetTable[I][0]] = SpillOffsetTable[I][1];
+ RegSpillOffsets[SpillOffsetTable[I].Reg] = SpillOffsetTable[I].Offset;
+}
+
+const TargetFrameLowering::SpillSlot *
+SystemZFrameLowering::getCalleeSavedSpillSlots(unsigned &NumEntries) const {
+ NumEntries = array_lengthof(SpillOffsetTable);
+ return SpillOffsetTable;
}
void SystemZFrameLowering::
@@ -127,14 +134,12 @@ spillCalleeSavedRegisters(MachineBasicBl
DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
// Scan the call-saved GPRs and find the bounds of the register spill area.
- unsigned SavedGPRFrameSize = 0;
unsigned LowGPR = 0;
unsigned HighGPR = SystemZ::R15D;
unsigned StartOffset = -1U;
for (unsigned I = 0, E = CSI.size(); I != E; ++I) {
unsigned Reg = CSI[I].getReg();
if (SystemZ::GR64BitRegClass.contains(Reg)) {
- SavedGPRFrameSize += 8;
unsigned Offset = RegSpillOffsets[Reg];
assert(Offset && "Unexpected GPR save");
if (StartOffset > Offset) {
@@ -144,9 +149,7 @@ spillCalleeSavedRegisters(MachineBasicBl
}
}
- // Save information about the range and location of the call-saved
- // registers, for use by the epilogue inserter.
- ZFI->setSavedGPRFrameSize(SavedGPRFrameSize);
+ // Save the range of call-saved registers, for use by the epilogue inserter.
ZFI->setLowSavedGPR(LowGPR);
ZFI->setHighSavedGPR(HighGPR);
@@ -449,11 +452,6 @@ int SystemZFrameLowering::getFrameIndexO
// offset is therefore negative.
int64_t Offset = (MFFrame->getObjectOffset(FI) +
MFFrame->getOffsetAdjustment());
- if (FI >= 0)
- // Non-fixed objects are allocated below the incoming stack pointer.
- // Account for the space at the top of the frame that we choose not
- // to allocate.
- Offset += getUnallocatedTopBytes(MF);
// Make the offset relative to the incoming stack pointer.
Offset -= getOffsetOfLocalArea();
@@ -465,20 +463,12 @@ int SystemZFrameLowering::getFrameIndexO
}
uint64_t SystemZFrameLowering::
-getUnallocatedTopBytes(const MachineFunction &MF) const {
- return MF.getInfo<SystemZMachineFunctionInfo>()->getSavedGPRFrameSize();
-}
-
-uint64_t SystemZFrameLowering::
getAllocatedStackSize(const MachineFunction &MF) const {
const MachineFrameInfo *MFFrame = MF.getFrameInfo();
// Start with the size of the local variables and spill slots.
uint64_t StackSize = MFFrame->getStackSize();
- // Remove any bytes that we choose not to allocate.
- StackSize -= getUnallocatedTopBytes(MF);
-
// Include space for an emergency spill slot, if one might be needed.
StackSize += getEmergencySpillSlotSize(MF);
Modified: llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.h?rev=185525&r1=185524&r2=185525&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.h (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZFrameLowering.h Wed Jul 3 04:11:00 2013
@@ -29,7 +29,9 @@ public:
SystemZFrameLowering(const SystemZTargetMachine &tm,
const SystemZSubtarget &sti);
- // Override FrameLowering.
+ // Override TargetFrameLowering.
+ virtual const SpillSlot *getCalleeSavedSpillSlots(unsigned &NumEntries) const
+ LLVM_OVERRIDE;
virtual void
processFunctionBeforeCalleeSavedScan(MachineFunction &MF,
RegScavenger *RS) const LLVM_OVERRIDE;
@@ -59,16 +61,6 @@ public:
MachineBasicBlock::iterator MI) const
LLVM_OVERRIDE;
- // The target-independent code automatically allocates save slots for
- // call-saved GPRs. However, we don't need those slots for SystemZ,
- // because the ABI sets aside GPR save slots in the caller-allocated part
- // of the frame. Since the target-independent code puts this unneeded
- // area at the top of the callee-allocated part of frame, we choose not
- // to allocate it and adjust the offsets accordingly. Return the
- // size of this unallocated area.
- // FIXME: seems a bit hackish.
- uint64_t getUnallocatedTopBytes(const MachineFunction &MF) const;
-
// Return the number of bytes in the callee-allocated part of the frame.
uint64_t getAllocatedStackSize(const MachineFunction &MF) const;
Modified: llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h?rev=185525&r1=185524&r2=185525&view=diff
==============================================================================
--- llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h (original)
+++ llvm/trunk/lib/Target/SystemZ/SystemZMachineFunctionInfo.h Wed Jul 3 04:11:00 2013
@@ -15,7 +15,6 @@
namespace llvm {
class SystemZMachineFunctionInfo : public MachineFunctionInfo {
- unsigned SavedGPRFrameSize;
unsigned LowSavedGPR;
unsigned HighSavedGPR;
unsigned VarArgsFirstGPR;
@@ -26,14 +25,8 @@ class SystemZMachineFunctionInfo : publi
public:
explicit SystemZMachineFunctionInfo(MachineFunction &MF)
- : SavedGPRFrameSize(0), LowSavedGPR(0), HighSavedGPR(0), VarArgsFirstGPR(0),
- VarArgsFirstFPR(0), VarArgsFrameIndex(0), RegSaveFrameIndex(0),
- ManipulatesSP(false) {}
-
- // Get and set the number of bytes allocated by generic code to store
- // call-saved GPRs.
- unsigned getSavedGPRFrameSize() const { return SavedGPRFrameSize; }
- void setSavedGPRFrameSize(unsigned bytes) { SavedGPRFrameSize = bytes; }
+ : LowSavedGPR(0), HighSavedGPR(0), VarArgsFirstGPR(0), VarArgsFirstFPR(0),
+ VarArgsFrameIndex(0), RegSaveFrameIndex(0), ManipulatesSP(false) {}
// Get and set the first call-saved GPR that should be saved and restored
// by this function. This is 0 if no GPRs need to be saved or restored.
More information about the llvm-commits
mailing list