1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-23 11:13:28 +01:00
llvm-mirror/lib/CodeGen/RegAllocBase.cpp
Chandler Carruth 2361db41db [Modules] Remove potential ODR violations by sinking the DEBUG_TYPE
define below all header includes in the lib/CodeGen/... tree. While the
current modules implementation doesn't check for this kind of ODR
violation yet, it is likely to grow support for it in the future. It
also removes one layer of macro pollution across all the included
headers.

Other sub-trees will follow.

llvm-svn: 206837
2014-04-22 02:02:50 +00:00

154 lines
5.6 KiB
C++

//===-- RegAllocBase.cpp - Register Allocator Base Class ------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the RegAllocBase class which provides common functionality
// for LiveIntervalUnion-based register allocators.
//
//===----------------------------------------------------------------------===//
#include "RegAllocBase.h"
#include "Spiller.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/LiveRangeEdit.h"
#include "llvm/CodeGen/LiveRegMatrix.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/VirtRegMap.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetRegisterInfo.h"
#ifndef NDEBUG
#include "llvm/ADT/SparseBitVector.h"
#endif
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Support/Timer.h"
using namespace llvm;
#define DEBUG_TYPE "regalloc"
STATISTIC(NumNewQueued , "Number of new live ranges queued");
// Temporary verification option until we can put verification inside
// MachineVerifier.
static cl::opt<bool, true>
VerifyRegAlloc("verify-regalloc", cl::location(RegAllocBase::VerifyEnabled),
cl::desc("Verify during register allocation"));
const char RegAllocBase::TimerGroupName[] = "Register Allocation";
bool RegAllocBase::VerifyEnabled = false;
//===----------------------------------------------------------------------===//
// RegAllocBase Implementation
//===----------------------------------------------------------------------===//
// Pin the vtable to this file.
void RegAllocBase::anchor() {}
void RegAllocBase::init(VirtRegMap &vrm,
LiveIntervals &lis,
LiveRegMatrix &mat) {
TRI = &vrm.getTargetRegInfo();
MRI = &vrm.getRegInfo();
VRM = &vrm;
LIS = &lis;
Matrix = &mat;
MRI->freezeReservedRegs(vrm.getMachineFunction());
RegClassInfo.runOnMachineFunction(vrm.getMachineFunction());
}
// Visit all the live registers. If they are already assigned to a physical
// register, unify them with the corresponding LiveIntervalUnion, otherwise push
// them on the priority queue for later assignment.
void RegAllocBase::seedLiveRegs() {
NamedRegionTimer T("Seed Live Regs", TimerGroupName, TimePassesIsEnabled);
for (unsigned i = 0, e = MRI->getNumVirtRegs(); i != e; ++i) {
unsigned Reg = TargetRegisterInfo::index2VirtReg(i);
if (MRI->reg_nodbg_empty(Reg))
continue;
enqueue(&LIS->getInterval(Reg));
}
}
// Top-level driver to manage the queue of unassigned VirtRegs and call the
// selectOrSplit implementation.
void RegAllocBase::allocatePhysRegs() {
seedLiveRegs();
// Continue assigning vregs one at a time to available physical registers.
while (LiveInterval *VirtReg = dequeue()) {
assert(!VRM->hasPhys(VirtReg->reg) && "Register already assigned");
// Unused registers can appear when the spiller coalesces snippets.
if (MRI->reg_nodbg_empty(VirtReg->reg)) {
DEBUG(dbgs() << "Dropping unused " << *VirtReg << '\n');
LIS->removeInterval(VirtReg->reg);
continue;
}
// Invalidate all interference queries, live ranges could have changed.
Matrix->invalidateVirtRegs();
// selectOrSplit requests the allocator to return an available physical
// register if possible and populate a list of new live intervals that
// result from splitting.
DEBUG(dbgs() << "\nselectOrSplit "
<< MRI->getRegClass(VirtReg->reg)->getName()
<< ':' << *VirtReg << " w=" << VirtReg->weight << '\n');
typedef SmallVector<unsigned, 4> VirtRegVec;
VirtRegVec SplitVRegs;
unsigned AvailablePhysReg = selectOrSplit(*VirtReg, SplitVRegs);
if (AvailablePhysReg == ~0u) {
// selectOrSplit failed to find a register!
// Probably caused by an inline asm.
MachineInstr *MI = nullptr;
for (MachineRegisterInfo::reg_instr_iterator
I = MRI->reg_instr_begin(VirtReg->reg), E = MRI->reg_instr_end();
I != E; ) {
MachineInstr *TmpMI = &*(I++);
if (TmpMI->isInlineAsm()) {
MI = TmpMI;
break;
}
}
if (MI)
MI->emitError("inline assembly requires more registers than available");
else
report_fatal_error("ran out of registers during register allocation");
// Keep going after reporting the error.
VRM->assignVirt2Phys(VirtReg->reg,
RegClassInfo.getOrder(MRI->getRegClass(VirtReg->reg)).front());
continue;
}
if (AvailablePhysReg)
Matrix->assign(*VirtReg, AvailablePhysReg);
for (VirtRegVec::iterator I = SplitVRegs.begin(), E = SplitVRegs.end();
I != E; ++I) {
LiveInterval *SplitVirtReg = &LIS->getInterval(*I);
assert(!VRM->hasPhys(SplitVirtReg->reg) && "Register already assigned");
if (MRI->reg_nodbg_empty(SplitVirtReg->reg)) {
DEBUG(dbgs() << "not queueing unused " << *SplitVirtReg << '\n');
LIS->removeInterval(SplitVirtReg->reg);
continue;
}
DEBUG(dbgs() << "queuing new interval: " << *SplitVirtReg << "\n");
assert(TargetRegisterInfo::isVirtualRegister(SplitVirtReg->reg) &&
"expect split value in virtual register");
enqueue(SplitVirtReg);
++NumNewQueued;
}
}
}