/*
* Copyright (c) 2016-2018,2019 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Copyright (c) 2004-2005 The Regents of The University of Michigan
* Copyright (c) 2013 Advanced Micro Devices, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Kevin Lim
*/
#include "cpu/o3/rename_map.hh"
#include <vector>
#include "cpu/reg_class.hh"
#include "debug/Rename.hh"
using namespace std;
/**** SimpleRenameMap methods ****/
SimpleRenameMap::SimpleRenameMap()
: freeList(NULL), zeroReg(IntRegClass,0)
{
}
void
SimpleRenameMap::init(unsigned size, SimpleFreeList *_freeList,
RegIndex _zeroReg)
{
assert(freeList == NULL);
assert(map.empty());
map.resize(size);
freeList = _freeList;
zeroReg = RegId(IntRegClass, _zeroReg);
}
SimpleRenameMap::RenameInfo
SimpleRenameMap::rename(const RegId& arch_reg)
{
PhysRegIdPtr renamed_reg;
// Record the current physical register that is renamed to the
// requested architected register.
PhysRegIdPtr prev_reg = map[arch_reg.flatIndex()];
if (arch_reg == zeroReg) {
assert(prev_reg->isZeroReg());
renamed_reg = prev_reg;
} else if (prev_reg->getNumPinnedWrites() > 0) {
// Do not rename if the register is pinned
assert(arch_reg.getNumPinnedWrites() == 0); // Prevent pinning the
// same register twice
DPRINTF(Rename, "Renaming pinned reg, numPinnedWrites %d\n",
prev_reg->getNumPinnedWrites());
renamed_reg = prev_reg;
renamed_reg->decrNumPinnedWrites();
} else {
renamed_reg = freeList->getReg();
map[arch_reg.flatIndex()] = renamed_reg;
renamed_reg->setNumPinnedWrites(arch_reg.getNumPinnedWrites());
renamed_reg->setNumPinnedWritesToComplete(
arch_reg.getNumPinnedWrites() + 1);
}
DPRINTF(Rename, "Renamed reg %d to physical reg %d (%d) old mapping was"
" %d (%d)\n",
arch_reg, renamed_reg->flatIndex(), renamed_reg->flatIndex(),
prev_reg->flatIndex(), prev_reg->flatIndex());
return RenameInfo(renamed_reg, prev_reg);
}
/**** UnifiedRenameMap methods ****/
void
UnifiedRenameMap::init(PhysRegFile *_regFile,
RegIndex _intZeroReg,
RegIndex _floatZeroReg,
UnifiedFreeList *freeList,
VecMode _mode)
{
regFile = _regFile;
vecMode = _mode;
intMap.init(TheISA::NumIntRegs, &(freeList->intList), _intZeroReg);
floatMap.init(TheISA::NumFloatRegs, &(freeList->floatList), _floatZeroReg);
vecMap.init(TheISA::NumVecRegs, &(freeList->vecList), (RegIndex)-1);
vecElemMap.init(TheISA::NumVecRegs * NVecElems,
&(freeList->vecElemList), (RegIndex)-1);
predMap.init(TheISA::NumVecPredRegs, &(freeList->predList), (RegIndex)-1);
ccMap.init(TheISA::NumCCRegs, &(freeList->ccList), (RegIndex)-1);
}
void
UnifiedRenameMap::switchFreeList(UnifiedFreeList* freeList)
{
if (vecMode == Enums::Elem) {
/* The free list should currently be tracking full registers. */
panic_if(freeList->hasFreeVecElems(),
"The free list is already tracking Vec elems");
panic_if(freeList->numFreeVecRegs() !=
regFile->numVecPhysRegs() - TheISA::NumVecRegs,
"The free list has lost vector registers");
/* Split the free regs. */
while (freeList->hasFreeVecRegs()) {
auto vr = freeList->getVecReg();
auto range = this->regFile->getRegElemIds(vr);
freeList->addRegs(range.first, range.second);
}
} else if (vecMode == Enums::Full) {
/* The free list should currently be tracking register elems. */
panic_if(freeList->hasFreeVecRegs(),
"The free list is already tracking full Vec");
panic_if(freeList->numFreeVecElems() !=
regFile->numVecElemPhysRegs() -
TheISA::NumVecRegs * TheISA::NumVecElemPerVecReg,
"The free list has lost vector register elements");
auto range = regFile->getRegIds(VecRegClass);
freeList->addRegs(range.first + TheISA::NumVecRegs, range.second);
/* We remove the elems from the free list. */
while (freeList->hasFreeVecElems())
freeList->getVecElem();
}
}
void
UnifiedRenameMap::switchMode(VecMode newVecMode)
{
if (newVecMode == Enums::Elem && vecMode == Enums::Full) {
/* Switch to vector element rename mode. */
vecMode = Enums::Elem;
/* Split the mapping of each arch reg. */
int vec_idx = 0;
for (auto &vec: vecMap) {
PhysRegFile::IdRange range = this->regFile->getRegElemIds(vec);
auto idx = 0;
for (auto phys_elem = range.first;
phys_elem < range.second; idx++, phys_elem++) {
setEntry(RegId(VecElemClass, vec_idx, idx), &(*phys_elem));
}
vec_idx++;
}
} else if (newVecMode == Enums::Full && vecMode == Enums::Elem) {
/* Switch to full vector register rename mode. */
vecMode = Enums::Full;
/* To rebuild the arch regs we take the easy road:
* 1.- Stitch the elems together into vectors.
* 2.- Replace the contents of the register file with the vectors
* 3.- Set the remaining registers as free
*/
TheISA::VecRegContainer new_RF[TheISA::NumVecRegs];
for (uint32_t i = 0; i < TheISA::NumVecRegs; i++) {
VecReg dst = new_RF[i].as<TheISA::VecElem>();
for (uint32_t l = 0; l < NVecElems; l++) {
RegId s_rid(VecElemClass, i, l);
PhysRegIdPtr s_prid = vecElemMap.lookup(s_rid);
dst[l] = regFile->readVecElem(s_prid);
}
}
for (uint32_t i = 0; i < TheISA::NumVecRegs; i++) {
PhysRegId pregId(VecRegClass, i, 0);
regFile->setVecReg(regFile->getTrueId(&pregId), new_RF[i]);
}
}
}