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-rw-r--r--lib/Target/SystemZ/SystemZFrameLowering.cpp83
1 files changed, 37 insertions, 46 deletions
diff --git a/lib/Target/SystemZ/SystemZFrameLowering.cpp b/lib/Target/SystemZ/SystemZFrameLowering.cpp
index c0d72c3..a58da90 100644
--- a/lib/Target/SystemZ/SystemZFrameLowering.cpp
+++ b/lib/Target/SystemZ/SystemZFrameLowering.cpp
@@ -14,19 +14,15 @@
#include "SystemZTargetMachine.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/RegisterScavenging.h"
#include "llvm/IR/Function.h"
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 +42,23 @@ SystemZFrameLowering::SystemZFrameLowering(const SystemZTargetMachine &tm,
{ 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 +135,12 @@ spillCalleeSavedRegisters(MachineBasicBlock &MBB,
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 +150,7 @@ spillCalleeSavedRegisters(MachineBasicBlock &MBB,
}
}
- // 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);
@@ -260,6 +264,22 @@ restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
return true;
}
+void SystemZFrameLowering::
+processFunctionBeforeFrameFinalized(MachineFunction &MF,
+ RegScavenger *RS) const {
+ MachineFrameInfo *MFFrame = MF.getFrameInfo();
+ uint64_t MaxReach = (MFFrame->estimateStackSize(MF) +
+ SystemZMC::CallFrameSize * 2);
+ if (!isUInt<12>(MaxReach)) {
+ // We may need register scavenging slots if some parts of the frame
+ // are outside the reach of an unsigned 12-bit displacement.
+ // Create 2 for the case where both addresses in an MVC are
+ // out of range.
+ RS->addScavengingFrameIndex(MFFrame->CreateStackObject(8, 8, false));
+ RS->addScavengingFrameIndex(MFFrame->CreateStackObject(8, 8, false));
+ }
+}
+
// Emit instructions before MBBI (in MBB) to add NumBytes to Reg.
static void emitIncrement(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
@@ -297,7 +317,7 @@ void SystemZFrameLowering::emitPrologue(MachineFunction &MF) const {
SystemZMachineFunctionInfo *ZFI = MF.getInfo<SystemZMachineFunctionInfo>();
MachineBasicBlock::iterator MBBI = MBB.begin();
MachineModuleInfo &MMI = MF.getMMI();
- const MCRegisterInfo &MRI = MMI.getContext().getRegisterInfo();
+ const MCRegisterInfo *MRI = MMI.getContext().getRegisterInfo();
const std::vector<CalleeSavedInfo> &CSI = MFFrame->getCalleeSavedInfo();
bool HasFP = hasFP(MF);
DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
@@ -322,7 +342,7 @@ void SystemZFrameLowering::emitPrologue(MachineFunction &MF) const {
if (SystemZ::GR64BitRegClass.contains(Reg)) {
int64_t Offset = SPOffsetFromCFA + RegSpillOffsets[Reg];
MMI.addFrameInst(MCCFIInstruction::createOffset(
- GPRSaveLabel, MRI.getDwarfRegNum(Reg, true), Offset));
+ GPRSaveLabel, MRI->getDwarfRegNum(Reg, true), Offset));
}
}
}
@@ -351,7 +371,7 @@ void SystemZFrameLowering::emitPrologue(MachineFunction &MF) const {
MCSymbol *SetFPLabel = MMI.getContext().CreateTempSymbol();
BuildMI(MBB, MBBI, DL, ZII->get(TargetOpcode::PROLOG_LABEL))
.addSym(SetFPLabel);
- unsigned HardFP = MRI.getDwarfRegNum(SystemZ::R11D, true);
+ unsigned HardFP = MRI->getDwarfRegNum(SystemZ::R11D, true);
MMI.addFrameInst(
MCCFIInstruction::createDefCfaRegister(SetFPLabel, HardFP));
@@ -379,7 +399,7 @@ void SystemZFrameLowering::emitPrologue(MachineFunction &MF) const {
// Add CFI for the this save.
if (!FPRSaveLabel)
FPRSaveLabel = MMI.getContext().CreateTempSymbol();
- unsigned Reg = MRI.getDwarfRegNum(I->getReg(), true);
+ unsigned Reg = MRI->getDwarfRegNum(I->getReg(), true);
int64_t Offset = getFrameIndexOffset(MF, I->getFrameIdx());
MMI.addFrameInst(MCCFIInstruction::createOffset(
FPRSaveLabel, Reg, SPOffsetFromCFA + Offset));
@@ -449,11 +469,6 @@ int SystemZFrameLowering::getFrameIndexOffset(const MachineFunction &MF,
// 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();
@@ -465,23 +480,12 @@ int SystemZFrameLowering::getFrameIndexOffset(const MachineFunction &MF,
}
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);
-
// We need to allocate the ABI-defined 160-byte base area whenever
// we allocate stack space for our own use and whenever we call another
// function.
@@ -491,19 +495,6 @@ getAllocatedStackSize(const MachineFunction &MF) const {
return StackSize;
}
-unsigned SystemZFrameLowering::
-getEmergencySpillSlotSize(const MachineFunction &MF) const {
- const MachineFrameInfo *MFFrame = MF.getFrameInfo();
- uint64_t MaxReach = MFFrame->getStackSize() + SystemZMC::CallFrameSize * 2;
- return isUInt<12>(MaxReach) ? 0 : 8;
-}
-
-unsigned SystemZFrameLowering::
-getEmergencySpillSlotOffset(const MachineFunction &MF) const {
- assert(getEmergencySpillSlotSize(MF) && "No emergency spill slot");
- return SystemZMC::CallFrameSize;
-}
-
bool
SystemZFrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
// The ABI requires us to allocate 160 bytes of stack space for the callee,
generated by cgit v1.1 at 2025-07-03 09:08:00 +0000