-//===-- FPMover.cpp - SparcV8 double-precision floating point move fixer --===//
+//===-- FPMover.cpp - Sparc double-precision floating point move fixer ----===//
//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
-// Turns FpMOVD instructions into FMOVS pairs after regalloc.
+// Expand FpMOVD/FpABSD/FpNEGD instructions into their single-precision pieces.
//
//===----------------------------------------------------------------------===//
-#include "SparcV8.h"
+#define DEBUG_TYPE "fpmover"
+#include "Sparc.h"
+#include "SparcSubtarget.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/Target/TargetMachine.h"
+#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/Debug.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/raw_ostream.h"
using namespace llvm;
-namespace {
- Statistic<> NumFpMOVDs ("fpmover", "# FpMOVD instructions translated");
- Statistic<> SkippedFpMOVDs ("fpmover", "# FpMOVD instructions skipped");
+STATISTIC(NumFpDs , "Number of instructions translated");
+STATISTIC(NoopFpDs, "Number of noop instructions removed");
+namespace {
struct FPMover : public MachineFunctionPass {
/// Target machine description which we query for reg. names, data
/// layout, etc.
///
TargetMachine &TM;
+
+ static char ID;
+ explicit FPMover(TargetMachine &tm)
+ : MachineFunctionPass(ID), TM(tm) { }
- FPMover (TargetMachine &tm) : TM (tm) { }
-
- virtual const char *getPassName () const {
- return "SparcV8 Double-FP Move Fixer";
- }
-
- bool runOnMachineBasicBlock (MachineBasicBlock &MBB);
- bool runOnMachineFunction (MachineFunction &F) {
- bool Changed = false;
- for (MachineFunction::iterator FI = F.begin (), FE = F.end ();
- FI != FE; ++FI)
- Changed |= runOnMachineBasicBlock (*FI);
- return Changed;
+ virtual const char *getPassName() const {
+ return "Sparc Double-FP Move Fixer";
}
+ bool runOnMachineBasicBlock(MachineBasicBlock &MBB);
+ bool runOnMachineFunction(MachineFunction &F);
};
+ char FPMover::ID = 0;
} // end of anonymous namespace
-/// createSparcV8FPMoverPass - Returns a pass that turns FpMOVD
+/// createSparcFPMoverPass - Returns a pass that turns FpMOVD
/// instructions into FMOVS instructions
///
-FunctionPass *llvm::createSparcV8FPMoverPass (TargetMachine &tm) {
- return new FPMover (tm);
+FunctionPass *llvm::createSparcFPMoverPass(TargetMachine &tm) {
+ return new FPMover(tm);
}
-static void doubleToSingleRegPair(unsigned doubleReg, unsigned &singleReg1,
- unsigned &singleReg2) {
- const unsigned EvenHalvesOfPairs[] = {
- V8::F0, V8::F2, V8::F4, V8::F6, V8::F8, V8::F10, V8::F12, V8::F14,
- V8::F16, V8::F18, V8::F20, V8::F22, V8::F24, V8::F26, V8::F28, V8::F30
+/// getDoubleRegPair - Given a DFP register, return the even and odd FP
+/// registers that correspond to it.
+static void getDoubleRegPair(unsigned DoubleReg, unsigned &EvenReg,
+ unsigned &OddReg) {
+ static const unsigned EvenHalvesOfPairs[] = {
+ SP::F0, SP::F2, SP::F4, SP::F6, SP::F8, SP::F10, SP::F12, SP::F14,
+ SP::F16, SP::F18, SP::F20, SP::F22, SP::F24, SP::F26, SP::F28, SP::F30
};
- const unsigned OddHalvesOfPairs[] = {
- V8::F1, V8::F3, V8::F5, V8::F7, V8::F9, V8::F11, V8::F13, V8::F15,
- V8::F17, V8::F19, V8::F21, V8::F23, V8::F25, V8::F27, V8::F29, V8::F31
+ static const unsigned OddHalvesOfPairs[] = {
+ SP::F1, SP::F3, SP::F5, SP::F7, SP::F9, SP::F11, SP::F13, SP::F15,
+ SP::F17, SP::F19, SP::F21, SP::F23, SP::F25, SP::F27, SP::F29, SP::F31
};
- const unsigned DoubleRegsInOrder[] = {
- V8::D0, V8::D1, V8::D2, V8::D3, V8::D4, V8::D5, V8::D6, V8::D7, V8::D8,
- V8::D9, V8::D10, V8::D11, V8::D12, V8::D13, V8::D14, V8::D15
+ static const unsigned DoubleRegsInOrder[] = {
+ SP::D0, SP::D1, SP::D2, SP::D3, SP::D4, SP::D5, SP::D6, SP::D7, SP::D8,
+ SP::D9, SP::D10, SP::D11, SP::D12, SP::D13, SP::D14, SP::D15
};
for (unsigned i = 0; i < sizeof(DoubleRegsInOrder)/sizeof(unsigned); ++i)
- if (DoubleRegsInOrder[i] == doubleReg) {
- singleReg1 = EvenHalvesOfPairs[i];
- singleReg2 = OddHalvesOfPairs[i];
+ if (DoubleRegsInOrder[i] == DoubleReg) {
+ EvenReg = EvenHalvesOfPairs[i];
+ OddReg = OddHalvesOfPairs[i];
return;
}
- assert (0 && "Can't find reg");
+ llvm_unreachable("Can't find reg");
}
/// runOnMachineBasicBlock - Fixup FpMOVD instructions in this MBB.
///
-bool FPMover::runOnMachineBasicBlock (MachineBasicBlock &MBB) {
+bool FPMover::runOnMachineBasicBlock(MachineBasicBlock &MBB) {
bool Changed = false;
- for (MachineBasicBlock::iterator I = MBB.begin (); I != MBB.end (); ++I)
- if (V8::FpMOVD == I->getOpcode ()) {
- unsigned NewSrcReg0 = 0, NewSrcReg1 = 0, NewDestReg0 = 0, NewDestReg1 = 0;
- doubleToSingleRegPair (I->getOperand (0).getReg (), NewDestReg0,
- NewDestReg1);
- doubleToSingleRegPair (I->getOperand (1).getReg (), NewSrcReg0,
- NewSrcReg1);
- MachineBasicBlock::iterator J = I;
- ++J;
- if (!(NewDestReg0 == NewSrcReg0 && NewDestReg1 == NewSrcReg1)) {
- I->setOpcode (V8::FMOVS);
- I->SetMachineOperandReg (0, NewDestReg0);
- I->SetMachineOperandReg (1, NewSrcReg0);
- DEBUG (std::cerr << "FPMover: new dest reg. is: " << NewDestReg0
- << "; modified instr is: " << *I);
- // Insert copy for the other half of the double:
- MachineInstr *MI2 =
- BuildMI (MBB, J, V8::FMOVS, 1, NewDestReg1).addReg (NewSrcReg1);
- DEBUG (std::cerr << "FPMover: new dest reg. is " << NewDestReg1
- << "; inserted instr is: " << *MI2);
- ++NumFpMOVDs;
- I = J;
- --I;
- } else {
- MBB.erase (I);
- ++SkippedFpMOVDs;
- I = J;
- }
+ for (MachineBasicBlock::iterator I = MBB.begin(); I != MBB.end(); ) {
+ MachineInstr *MI = I++;
+ DebugLoc dl = MI->getDebugLoc();
+ if (MI->getOpcode() == SP::FpMOVD || MI->getOpcode() == SP::FpABSD ||
+ MI->getOpcode() == SP::FpNEGD) {
Changed = true;
+ unsigned DestDReg = MI->getOperand(0).getReg();
+ unsigned SrcDReg = MI->getOperand(1).getReg();
+ if (DestDReg == SrcDReg && MI->getOpcode() == SP::FpMOVD) {
+ MBB.erase(MI); // Eliminate the noop copy.
+ ++NoopFpDs;
+ continue;
+ }
+
+ unsigned EvenSrcReg = 0, OddSrcReg = 0, EvenDestReg = 0, OddDestReg = 0;
+ getDoubleRegPair(DestDReg, EvenDestReg, OddDestReg);
+ getDoubleRegPair(SrcDReg, EvenSrcReg, OddSrcReg);
+
+ const TargetInstrInfo *TII = TM.getInstrInfo();
+ if (MI->getOpcode() == SP::FpMOVD)
+ MI->setDesc(TII->get(SP::FMOVS));
+ else if (MI->getOpcode() == SP::FpNEGD)
+ MI->setDesc(TII->get(SP::FNEGS));
+ else if (MI->getOpcode() == SP::FpABSD)
+ MI->setDesc(TII->get(SP::FABSS));
+ else
+ llvm_unreachable("Unknown opcode!");
+
+ MI->getOperand(0).setReg(EvenDestReg);
+ MI->getOperand(1).setReg(EvenSrcReg);
+ DEBUG(errs() << "FPMover: the modified instr is: " << *MI);
+ // Insert copy for the other half of the double.
+ if (DestDReg != SrcDReg) {
+ MI = BuildMI(MBB, I, dl, TM.getInstrInfo()->get(SP::FMOVS), OddDestReg)
+ .addReg(OddSrcReg);
+ DEBUG(errs() << "FPMover: the inserted instr is: " << *MI);
+ }
+ ++NumFpDs;
}
+ }
+ return Changed;
+}
+
+bool FPMover::runOnMachineFunction(MachineFunction &F) {
+ // If the target has V9 instructions, the fp-mover pseudos will never be
+ // emitted. Avoid a scan of the instructions to improve compile time.
+ if (TM.getSubtarget<SparcSubtarget>().isV9())
+ return false;
+
+ bool Changed = false;
+ for (MachineFunction::iterator FI = F.begin(), FE = F.end();
+ FI != FE; ++FI)
+ Changed |= runOnMachineBasicBlock(*FI);
return Changed;
}