llvm-mirror/lib/CodeGen/ScheduleDAGEmit.cpp
Dan Gohman 0ac693a89e Improve MachineMemOperand handling.
- Allocate MachineMemOperands and MachineMemOperand lists in MachineFunctions.
   This eliminates MachineInstr's std::list member and allows the data to be
   created by isel and live for the remainder of codegen, avoiding a lot of
   copying and unnecessary translation. This also shrinks MemSDNode.
 - Delete MemOperandSDNode. Introduce MachineSDNode which has dedicated
   fields for MachineMemOperands.
 - Change MemSDNode to have a MachineMemOperand member instead of its own
   fields with the same information. This introduces some redundancy, but
   it's more consistent with what MachineInstr will eventually want.
 - Ignore alignment when searching for redundant loads for CSE, but remember
   the greatest alignment.

Target-specific code which previously used MemOperandSDNodes with generic
SDNodes now use MemIntrinsicSDNodes, with opcodes in a designated range
so that the SelectionDAG framework knows that MachineMemOperand information
is available.

llvm-svn: 82794
2009-09-25 20:36:54 +00:00

68 lines
2.5 KiB
C++

//===---- ScheduleDAGEmit.cpp - Emit routines for the ScheduleDAG class ---===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This implements the Emit routines for the ScheduleDAG class, which creates
// MachineInstrs according to the computed schedule.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "pre-RA-sched"
#include "llvm/CodeGen/ScheduleDAG.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Target/TargetData.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MathExtras.h"
using namespace llvm;
void ScheduleDAG::EmitNoop() {
TII->insertNoop(*BB, InsertPos);
}
void ScheduleDAG::EmitPhysRegCopy(SUnit *SU,
DenseMap<SUnit*, unsigned> &VRBaseMap) {
for (SUnit::const_pred_iterator I = SU->Preds.begin(), E = SU->Preds.end();
I != E; ++I) {
if (I->isCtrl()) continue; // ignore chain preds
if (I->getSUnit()->CopyDstRC) {
// Copy to physical register.
DenseMap<SUnit*, unsigned>::iterator VRI = VRBaseMap.find(I->getSUnit());
assert(VRI != VRBaseMap.end() && "Node emitted out of order - late");
// Find the destination physical register.
unsigned Reg = 0;
for (SUnit::const_succ_iterator II = SU->Succs.begin(),
EE = SU->Succs.end(); II != EE; ++II) {
if (II->getReg()) {
Reg = II->getReg();
break;
}
}
TII->copyRegToReg(*BB, InsertPos, Reg, VRI->second,
SU->CopyDstRC, SU->CopySrcRC);
} else {
// Copy from physical register.
assert(I->getReg() && "Unknown physical register!");
unsigned VRBase = MRI.createVirtualRegister(SU->CopyDstRC);
bool isNew = VRBaseMap.insert(std::make_pair(SU, VRBase)).second;
isNew = isNew; // Silence compiler warning.
assert(isNew && "Node emitted out of order - early");
TII->copyRegToReg(*BB, InsertPos, VRBase, I->getReg(),
SU->CopyDstRC, SU->CopySrcRC);
}
break;
}
}