itx_reader.cc

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· CC 代码 · 共 194 行

/*
 * Copyright (c) 2004, 2005
 * The Regents of The University of Michigan
 * All Rights Reserved
 *
 * This code is part of the M5 simulator.
 *
 * Permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any
 * purpose, so long as the copyright notice above, this grant of
 * permission, and the disclaimer below appear in all copies made; and
 * so long as the name of The University of Michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.
 *
 * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION FROM THE
 * UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
 * WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE. THE REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE
 * LIABLE FOR ANY DAMAGES, INCLUDING DIRECT, SPECIAL, INDIRECT,
 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
 * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGES.
 *
 * Authors: Erik G. Hallnor
 */

/**
 * @file
 * Declaration of a Intel ITX memory trace format reader.
 */
#include <sstream>

#include "base/misc.hh" // for fatal
#include "cpu/trace/reader/itx_reader.hh"
#include "params/ITXReader.hh"

using namespace std;

ITXReader::ITXReader(const string &name, const string &filename)
    : MemTraceReader(name)
{
    if (strcmp((filename.c_str() + filename.length() -3), ".gz") == 0) {
        // Compressed file, need to use a pipe to gzip.
        stringstream buf;
        buf << "gzip -d -c " << filename << endl;
        trace = popen(buf.str().c_str(), "r");
    } else {
        trace = fopen(filename.c_str(), "rb");
    }
    if (!trace) {
        fatal("Can't open file %s", filename);
    }
    traceFormat = 0;
    int c;
    for (int i = 0; i < 4; ++i) {
        c = getc(trace);
        if (c == EOF) {
            fatal("Unexpected end of trace file.");
        }
        traceFormat |= (c & 0xff) << (8 * i);
    }
    if (traceFormat > 2)
        fatal("Invalid trace format.");
}

Tick
ITXReader::getNextReq(MemReqPtr &req)
{
    MemReqPtr tmp_req = new MemReq();
    bool phys_val;
    do {
        int c = getc(trace);
        if (c != EOF) {
            // Decode first byte
            // phys_val<1> | type <2:0> | size <3:0>
            phys_val = c & 0x80;
            tmp_req->size = (c & 0x0f) + 1;
            int type = (c & 0x70) >> 4;

            // Could be a compressed instruction entry, expand if necessary
            if (type == ITXCodeComp) {
                if (traceFormat != 2) {
                    fatal("Compressed code entry in non CompCode trace.");
                }
                if (!codeVirtValid) {
                    fatal("Corrupt CodeComp entry.");
                }

                tmp_req->vaddr = codeVirtAddr;
                codeVirtAddr += tmp_req->size;
                if (phys_val) {
                    if (!codePhysValid) {
                        fatal("Corrupt CodeComp entry.");
                    }
                    tmp_req->paddr = codePhysAddr;
                    if (((tmp_req->paddr & 0xfff) + tmp_req->size) & ~0xfff) {
                        // Crossed page boundary, next physical address is
                        // invalid
                        codePhysValid = false;
                    } else {
                        codePhysAddr += tmp_req->size;
                    }
                    assert(tmp_req->paddr >> 36 == 0);
                } else {
                    codePhysValid = false;
                }
                type = ITXCode;
                tmp_req->cmd = Read;
            } else {
                // Normal entry
                tmp_req->vaddr = 0;
                for (int i = 0; i < 4; ++i) {
                    c = getc(trace);
                    if (c == EOF) {
                        fatal("Unexpected end of trace file.");
                    }
                    tmp_req->vaddr |= (c & 0xff) << (8 * i);
                }
                if (type == ITXCode) {
                    codeVirtAddr = tmp_req->vaddr + tmp_req->size;
                    codeVirtValid = true;
                }
                tmp_req->paddr = 0;
                if (phys_val) {
                    c = getc(trace);
                    if (c == EOF) {
                        fatal("Unexpected end of trace file.");
                    }
                    // Get the page offset from the virtual address.
                    tmp_req->paddr = tmp_req->vaddr & 0xfff;
                    tmp_req->paddr |= (c & 0xf0) << 8;
                    tmp_req->paddr |= (Addr)(c & 0x0f) << 32;
                    for (int i = 2; i < 4; ++i) {
                        c = getc(trace);
                        if (c == EOF) {
                            fatal("Unexpected end of trace file.");
                        }
                        tmp_req->paddr |= (Addr)(c & 0xff) << (8 * i);
                    }
                    if (type == ITXCode) {
                        if (((tmp_req->paddr & 0xfff) + tmp_req->size)
                            & ~0xfff) {
                            // Crossing the page boundary, next physical
                            // address isn't valid
                            codePhysValid = false;
                        } else {
                            codePhysAddr = tmp_req->paddr + tmp_req->size;
                            codePhysValid = true;
                        }
                    }
                    assert(tmp_req->paddr >> 36 == 0);
                } else if (type == ITXCode) {
                    codePhysValid = false;
                }
                switch(type) {
                  case ITXRead:
                    tmp_req->cmd = Read;
                    break;
                  case ITXWrite:
                    tmp_req->cmd = Write;
                    break;
                  case ITXWriteback:
                    tmp_req->cmd = Writeback;
                    break;
                  case ITXCode:
                    tmp_req->cmd = Read;
                    tmp_req->flags |= INST_READ;
                    break;
                  default:
                    fatal("Unknown ITX type");
                }
            }
        } else {
            // EOF need to return a null request
            MemReqPtr null_req;
            req = null_req;
            return 0;
        }
    } while (!phys_val);
    req = tmp_req;
    assert(!req || (req->paddr >> 36) == 0);
    return 0;
}

ITXReader *
ITXReaderParams::create()
{
    return new ITXReader(name, filename);
}