ObjectFileWriterPass.cpp

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/* src/vm/jit/compiler2/ObjectFileWriterPass.cpp - ObjectFileWriterPass

   Copyright (C) 2013
   CACAOVM - Verein zur Foerderung der freien virtuellen Maschine CACAO

   This file is part of CACAO.

   This program is free software; you can redistribute it and/or
   modify it under the terms of the GNU General Public License as
   published by the Free Software Foundation; either version 2, or (at
   your option) any later version.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

*/

#include "vm/jit/compiler2/ObjectFileWriterPass.hpp"
#include "vm/jit/compiler2/PassManager.hpp"
#include "vm/jit/compiler2/JITData.hpp"
#include "vm/jit/compiler2/PassUsage.hpp"
#include "vm/jit/compiler2/CodeGenPass.hpp"
#include "vm/jit/compiler2/MethodDescriptor.hpp"

#include "vm/jit/codegen-common.hpp"

#include "toolbox/logging.hpp"

#include "vm/jit/jit.hpp"
#include "vm/jit/code.hpp"
#include "vm/rt-timing.hpp"

#if defined(ENABLE_DISASSEMBLER)

#if !defined(WITH_BINUTILS_DISASSEMBLER)
#error ObjectFileWriterPass requires binutils bfd library.
#endif

#include <bfd.h>
#include <string>

#endif // defined(ENABLE_DISASSEMBLER)

#define DEBUG_NAME "compiler2/ObjectFileWriter"

#if defined(ENABLE_DISASSEMBLER)
RT_REGISTER_TIMER(obj_writter_timer,"objectwriter","object writer execution time")
#endif

namespace {

#if defined(ENABLE_DISASSEMBLER)
template<typename T>
inline void check_bfd_error(T* t) {
    if (!t) {
        // error
        ABORT_MSG("ObjectFileWriterPass Error", "Error: " << bfd_errmsg(bfd_get_error()));
    }
}
inline void check_bfd_error(bfd_boolean b) {
    if (b == FALSE) {
        // error
        ABORT_MSG("ObjectFileWriterPass Error", "Error: " << bfd_errmsg(bfd_get_error()));
    }
}
#endif // defined(ENABLE_DISASSEMBLER)

} // end anonymous namespace

namespace cacao {
namespace jit {
namespace compiler2 {

#define FAKE_DATASEC
bool ObjectFileWriterPass::run(JITData &JD) {
#if defined(ENABLE_DISASSEMBLER)
    RT_TIMER_START(obj_writter_timer);
    Method *M = JD.get_Method();
    //CodeGenPass *CG = get_Pass<CodeGenPass>();
    codeinfo*     code = JD.get_jitdata()->code;

    const char* bfd_arch = "i386:x86-64";
    const char* bfd_target = "elf64-x86-64";
    std::string symbol_name(M->get_name_utf8().begin(),M->get_name_utf8().size());
    std::string class_name(M->get_class_name_utf8().begin(),M->get_class_name_utf8().size());
    std::string filename = class_name + "." + symbol_name + ".o";
    //JD.get_Method()->get_MethodDescriptor().
    //
    LOG("Object file name: " << filename.c_str() << nl);
    LOG(".text symbol name: " << symbol_name.c_str() << nl);

    #if 0
    if (DEBUG_COND_N(3)) {
        const char ** target_list = bfd_target_list();
        while (*target_list) {
            LOG("target: " << *target_list << nl);
            ++target_list;
        }
    }
    if (DEBUG_COND_N(3)) {
        const char ** arch_list = bfd_arch_list();
        while (*arch_list) {
            LOG("arch: " << *arch_list << nl);
            ++arch_list;
        }
    }
    #endif
    // open file
    LOG2("open file" << nl);
    bfd *abfd = bfd_openw(filename.c_str(),bfd_target);
    check_bfd_error(abfd);

    // set architecture
    LOG2("set architecture" << nl);
    const bfd_arch_info_type *arch_info = bfd_scan_arch (bfd_arch);
    check_bfd_error(arch_info);

    bfd_set_arch_info(abfd,arch_info);
    // set format
    bfd_set_format(abfd, bfd_object);

    // get section lengths
    std::size_t dseglen = code->entrypoint - code->mcode;
    std::size_t codelen = code->mcodelength - dseglen;
    //dseglen =0;

    // create data_section
    asection *data_section = NULL;
    if (dseglen) {
        LOG2("create data_section" << nl);
        data_section = bfd_make_section_anyway_with_flags(abfd, ".rodata",
            SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_DATA );
        check_bfd_error(data_section);
        // set data_section size
        LOG2("set data_section size" << nl);
        check_bfd_error(bfd_set_section_size(abfd, data_section, dseglen));
        // set alignment
        data_section->alignment_power = 2;
    }

    // create code_section
    LOG2("create code_section" << nl);
    asection *code_section = bfd_make_section_anyway_with_flags(abfd, ".text",
        SEC_HAS_CONTENTS | SEC_ALLOC | SEC_LOAD | SEC_READONLY | SEC_CODE );
    check_bfd_error(code_section);
    // set code_section size
    LOG2("set code_section size" << nl);
    #ifdef FAKE_DATASEC
    if (dseglen) {
        codelen = 8 + dseglen + codelen;
    }
    #endif
    check_bfd_error(bfd_set_section_size(abfd, code_section,codelen));
    // set alignment
    code_section->alignment_power = 2;

    #if 0
    // create relocation entries
    reloc_howto_type* howto = bfd_reloc_type_lookup(abfd, BFD_RELOC_32_PCREL);
    arelent reloc_entry = {
        0,
        4,
        0,
        howto
    };
    char *err;
    bfd_install_relocation(
        abfd,
        &reloc_entry,
        NULL,
        8,
        //code_section,
        data_section,
        &err);
    #if 0
    bfd_reloc_status_type bfd_install_relocation
        (bfd *abfd,
        arelent *reloc_entry,
        void *data, bfd_vma data_start,
        asection *input_section,
        char **error_message);
    #endif
    #endif

    // create symbol
    LOG2("create symbol" << nl);
    asymbol *new_smbl = bfd_make_empty_symbol (abfd);
    new_smbl->name = symbol_name.c_str();
    new_smbl->section = code_section;
    new_smbl->flags = BSF_GLOBAL;

    // symbol list
    asymbol *ptrs[2];
    ptrs[0] = new_smbl;
    ptrs[1] = 0;

    // insert symbol list
    LOG2("insert symbol list" << nl);
    check_bfd_error(bfd_set_symtab(abfd, ptrs, 1));

    // set contents
    // this starts writing so do it at the end
    if (dseglen) {
        LOG2("set data_section contents" << nl);
        check_bfd_error(bfd_set_section_contents(abfd,
            data_section, code->mcode,0,dseglen));
    }
    LOG2("set code_section contents" << nl);
    #ifdef FAKE_DATASEC
    if (dseglen) {
        alloc::vector<u1>::type buffer(codelen);
        buffer[0] = 0xe9; // jmp rel32
        buffer[1] = ((dseglen + 3) >> 0) & 0xff;
        buffer[2] = ((dseglen + 3) >> 8) & 0xff;
        buffer[3] = ((dseglen + 3) >>16) & 0xff;
        buffer[4] = ((dseglen + 3) >>32) & 0xff;
        // copy dataseg
        memcpy(&buffer[8],code->mcode,dseglen);
        // copy codeseg
        memcpy(&buffer[8+dseglen],code->entrypoint,codelen - (dseglen + 8));
        check_bfd_error(bfd_set_section_contents(abfd,
            code_section, &buffer.front(),0,codelen));
    } else
    #endif
    check_bfd_error(bfd_set_section_contents(abfd,
        code_section, code->entrypoint,0,codelen));

    // close file
    bfd_close(abfd);

    RT_TIMER_STOP(obj_writter_timer);
#endif // defined(ENABLE_DISASSEMBLER)
    return true;
}

// pass usage
PassUsage& ObjectFileWriterPass::get_PassUsage(PassUsage &PU) const {
    PU.add_requires<CodeGenPass>();
    return PU;
}

// the address of this variable is used to identify the pass
char ObjectFileWriterPass::ID = 0;

Option<bool> ObjectFileWriterPass::enabled("ObjectFileWriterPass","compiler2: enable ObjectFileWriterPass",false,::cacao::option::xx_root());

// register pass
static PassRegistry<ObjectFileWriterPass> X("ObjectFileWriterPass");

} // end namespace compiler2
} // end namespace jit
} // end namespace cacao


/*
 * These are local overrides for various environment variables in Emacs.
 * Please do not remove this and leave it at the end of the file, where
 * Emacs will automagically detect them.
 * ---------------------------------------------------------------------
 * Local variables:
 * mode: c++
 * indent-tabs-mode: t
 * c-basic-offset: 4
 * tab-width: 4
 * End:
 * vim:noexpandtab:sw=4:ts=4:
 */