#include "llvm/Pass.h"
#include "llvm/Support/CodeGen.h"
+#include "llvm/Support/CommandLine.h"
#include <string>
+extern llvm::cl::opt<bool> UseIPRA;
+
namespace llvm {
class PassConfigImpl;
virtual bool canUseAsEpilogue(const MachineBasicBlock &MBB) const {
return true;
}
+
+ /// Check if given function is safe for not having callee saved registers.
+ /// This is used when interprocedural register allocation is enabled.
+ static bool isSafeForNoCSROpt(const Function *F) {
+ if (!F->hasLocalLinkage() || F->hasAddressTaken() ||
+ !F->hasFnAttribute(Attribute::NoRecurse))
+ return false;
+ // Function should not be optimized as tail call.
+ for (const User *U : F->users())
+ if (auto CS = ImmutableCallSite(U))
+ if (CS.isTailCall())
+ return false;
+ return true;
+ }
};
} // End llvm namespace
///
//===----------------------------------------------------------------------===//
+#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/RegisterUsageInfo.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
+#include "llvm/Target/TargetFrameLowering.h"
using namespace llvm;
#define DEBUG_TYPE "ip-regalloc"
+STATISTIC(NumCSROpt,
+ "Number of functions optimized for callee saved registers");
+
namespace llvm {
void initializeRegUsageInfoCollectorPass(PassRegistry &);
}
unsigned RegMaskSize = (TRI->getNumRegs() + 31) / 32;
RegMask.resize(RegMaskSize, 0xFFFFFFFF);
+ const Function *F = MF.getFunction();
+
PhysicalRegisterUsageInfo *PRUI = &getAnalysis<PhysicalRegisterUsageInfo>();
PRUI->setTargetMachine(&TM);
if (MRI->isPhysRegModified(PReg, true))
markRegClobbered(TRI, &RegMask[0], PReg);
- const uint32_t *CallPreservedMask =
- TRI->getCallPreservedMask(MF, MF.getFunction()->getCallingConv());
- // Set callee saved register as preserved.
- for (unsigned i = 0; i < RegMaskSize; ++i)
- RegMask[i] = RegMask[i] | CallPreservedMask[i];
+ if (!TargetFrameLowering::isSafeForNoCSROpt(F)) {
+ const uint32_t *CallPreservedMask =
+ TRI->getCallPreservedMask(MF, F->getCallingConv());
+ // Set callee saved register as preserved.
+ for (unsigned i = 0; i < RegMaskSize; ++i)
+ RegMask[i] = RegMask[i] | CallPreservedMask[i];
+ } else {
+ ++NumCSROpt;
+ DEBUG(dbgs() << MF.getName()
+ << " function optimized for not having CSR.\n");
+ }
for (unsigned PReg = 1, PRegE = TRI->getNumRegs(); PReg < PRegE; ++PReg)
if (MachineOperand::clobbersPhysReg(&(RegMask[0]), PReg))
DEBUG(dbgs() << " \n----------------------------------------\n");
- PRUI->storeUpdateRegUsageInfo(MF.getFunction(), std::move(RegMask));
+ PRUI->storeUpdateRegUsageInfo(F, std::move(RegMask));
return false;
}
//===----------------------------------------------------------------------===//
#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/CodeGen/TargetPassConfig.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Function.h"
+#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetSubtargetInfo.h"
#include <cstdlib>
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);
// Resize before the early returns. Some backends expect that
// SavedRegs.size() == TRI.getNumRegs() after this call even if there are no
// saved registers.
SavedRegs.resize(TRI.getNumRegs());
+ // When interprocedural register allocation is enabled caller saved registers
+ // are preferred over callee saved registers.
+ if (UseIPRA && isSafeForNoCSROpt(MF.getFunction()))
+ return;
+
+ // Get the callee saved register list...
+ const MCPhysReg *CSRegs = TRI.getCalleeSavedRegs(&MF);
+
// Early exit if there are no callee saved registers.
if (!CSRegs || CSRegs[0] == 0)
return;
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/Verifier.h"
#include "llvm/MC/MCAsmInfo.h"
-#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"