jit.cpp

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/* src/vm/jit/jit.cpp - Just-In-Time compiler

   Copyright (C) 1996-2014
   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 <cassert>                         // for assert
#include <stdint.h>                        // for uintptr_t
#include "config.h"                        // for ENABLE_JIT, etc
#include "md.hpp"                          // for md_cacheflush
#include "mm/dumpmemory.hpp"               // for DumpMemory, DumpMemoryArea
#include "native/native.hpp"               // for NativeMethods
#include "threads/mutex.hpp"               // for Mutex
#include "toolbox/logging.hpp"             // for log_message_method, etc
#include "vm/class.hpp"                    // for classinfo
#include "vm/global.hpp"                   // for functionptr
#include "vm/globals.hpp"
#include "vm/hook.hpp"                     // for jit_generated
#include "vm/initialize.hpp"               // for initialize_class
#include "vm/jit/jit.hpp"
#include "vm/jit/allocator/simplereg.hpp"  // for regalloc, etc
#include "vm/jit/cfg.hpp"                  // for cfg_build
#include "vm/jit/code.hpp"                 // for codeinfo, etc
#include "vm/jit/codegen-common.hpp"       // for codegen_setup, etc
#include "vm/jit/disass.hpp"
#include "vm/jit/dseg.hpp"                 // for dseg_display
#include "vm/jit/ir/bytecode.hpp"
#include "vm/jit/ir/icmd.hpp"              // for ::ICMD_IFNONNULL, etc
#include "vm/jit/optimizing/ifconv.hpp"    // for ifconv_static
#include "vm/jit/optimizing/reorder.hpp"
#include "vm/jit/parse.hpp"                // for parse
#include "vm/jit/reg.hpp"                  // for reg_setup, registerdata
#include "vm/jit/replace.hpp"              // for replace_activate_replacement_points
#include "vm/jit/show.hpp"                 // for show_filters_apply, etc
#include "vm/jit/stack.hpp"                // for stack_analyse, stack_init
#include "vm/jit/stubs.hpp"                // for NativeStub
#include "vm/jit/verify/typecheck.hpp"     // for typecheck
#include "vm/method.hpp"                   // for methodinfo, method_print
#include "vm/options.hpp"                  // for compileverbose, etc
#include "vm/rt-timing.hpp"
#include "vm/statistics.hpp"               // for StatSumGroup, StatVar, etc
#include "vm/types.hpp"                    // for u1, s4, ptrint
#include "vm/vm.hpp"                       // for VM, vm_abort

#if defined(ENABLE_LSRA) && !defined(ENABLE_SSA)
# include "vm/jit/allocator/lsra.hpp"
#endif

#if defined(ENABLE_SSA)
# include "vm/jit/optimizing/lsra.hpp"
# include "vm/jit/optimizing/ssa.hpp"
#endif

#if defined(ENABLE_INLINING)
# include "vm/jit/inline/inline.hpp"
#endif

#if defined(ENABLE_IFCONV)
# include "vm/jit/optimizing/ifconv.hpp"
#endif

#if defined(ENABLE_LOOP)
# include "vm/jit/loop/loop.hpp"
#endif

#if defined(ENABLE_COMPILER2)
#include "vm/jit/compiler2/Compiler.hpp"
#include "vm/jit/compiler2/JITData.hpp"
#include "vm/jit/compiler2/ObjectFileWriterPass.hpp"
#endif

/* debug macros ***************************************************************/

#if !defined(NDEBUG)
#define DEBUG_JIT_COMPILEVERBOSE(x)             \
    do {                                        \
        if (compileverbose) {                   \
            log_message_method(x, m);           \
        }                                       \
    } while (0)
#else
#define DEBUG_JIT_COMPILEVERBOSE(x)    /* nothing */
#endif

#if !defined(NDEBUG)
# define TRACECOMPILERCALLS()                               \
    do {                                                    \
        if (opt_TraceCompilerCalls) {                       \
            log_start();                                    \
            log_print("[JIT compiler started: method=");    \
            method_print(m);                                \
            log_print("]");                                 \
            log_finish();                                   \
        }                                                   \
    } while (0)
#else
# define TRACECOMPILERCALLS()
#endif

STAT_REGISTER_VAR(int,count_jit_calls,0,"jit calls","Number of JIT compiler calls")
STAT_REGISTER_VAR(int,count_methods,0,"compiled methods","Number of compiled methods")
// TODO regression: old framework also printed (count_javacodesize - count_methods * 18)
STAT_REGISTER_VAR(int,count_javacodesize,0,"java code size","Size of compiled JavaVM instructions")
STAT_REGISTER_VAR(int,count_javaexcsize,0,"java exc.tbl. size","Size of compiled Exception Tables")
STAT_REGISTER_VAR(int,count_tryblocks,0,"try blocks","Number of Try-Blocks")
STAT_REGISTER_VAR(int,count_methods_allocated_by_lsra,0,"meth. alloc. lsra","Methods allocated by LSRA")

STAT_REGISTER_VAR_EXTERN(int,count_interface_size,0,"interface size","Number of interface slots")
STAT_REGISTER_VAR_EXTERN(int,count_locals_conflicts,0,"locals conflicts","Conflicts between local Variables")
STAT_REGISTER_VAR_EXTERN(int,count_locals_spilled,0,"locals spilled","Local Variables held in Memory")
STAT_REGISTER_VAR_EXTERN(int,count_locals_register,0,"locals register","Local Variables held in Registers")
STAT_REGISTER_VAR_EXTERN(int,count_ss_spilled,0,"ss spilled","Stackslots held in Memory")
STAT_REGISTER_VAR_EXTERN(int,count_ss_register,0,"ss register","Stackslots held in Registers")
STAT_REGISTER_VAR_EXTERN(int,count_argument_reg_ss,0,"argument reg ss","Number of Argument stack slots in register")
STAT_REGISTER_VAR_EXTERN(int,count_argument_mem_ss,0,"argument mem ss","Number of Argument stack slots in memory")

STAT_REGISTER_SUM_GROUP(spill_write_stat,"spills write","Number of Spills (write to memory)")
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_write_ila,0,"spill write i/l/a","Int, Long, Array Spills (write to memory)",spill_write_stat)
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_write_flt,0,"spill write float","Float Spills (write to memory)",spill_write_stat)
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_write_dbl,0,"spill write double","Double Spills (write to memory)",spill_write_stat)

STAT_REGISTER_SUM_GROUP(spill_read_stat,"spills read","Number of Spills (read from memory)")
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_read_ila,0,"spill read i/l/a","Int, Long, Array Spills (read from memory)",spill_read_stat)
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_read_flt,0,"spill read float","Float Spills (read from memory)",spill_read_stat)
STAT_REGISTER_GROUP_VAR_EXTERN(int,count_spills_read_dbl,0,"spill read double","Double Spills (read from memory)",spill_read_stat)

/* jit_init ********************************************************************

   Initializes the JIT subsystem.

*******************************************************************************/

void jit_init(void)
{
    TRACESUBSYSTEMINITIALIZATION("jit_init");

#if defined(ENABLE_JIT)
    /* initialize stack analysis subsystem */

    (void) stack_init();
#endif

    /* initialize show subsystem */

#if !defined(NDEBUG)
    (void) show_init();
#endif

    /* initialize codegen subsystem */

    codegen_init();

    /* initialize code subsystem */

    (void) code_init();

    /* Machine dependent initialization. */

#if defined(ENABLE_JIT)
# if defined(ENABLE_INTRP)
    if (opt_intrp)
        intrp_md_init();
    else
# endif
        md_init();
#else
    intrp_md_init();
#endif
}

#define DEBUG_NAME "jit"

/* jit_close *******************************************************************

   Close the JIT subsystem.

*******************************************************************************/

void jit_close(void)
{
    /* nop */
}


/* dummy function, used when there is no JavaVM code available                */

static u1 *do_nothing_function(void)
{
    return NULL;
}


/* jit_jitdata_new *************************************************************

   Allocates and initalizes a new jitdata structure.

*******************************************************************************/

jitdata *jit_jitdata_new(methodinfo *m)
{
    jitdata  *jd;
    codeinfo *code;

    /* allocate jitdata structure and fill it */

    jd = (jitdata*) DumpMemory::allocate(sizeof(jitdata));

    jd->m     = m;
    jd->cd    = (codegendata*) DumpMemory::allocate(sizeof(codegendata));
    jd->rd    = (registerdata*) DumpMemory::allocate(sizeof(registerdata));
#if defined(ENABLE_LOOP)
    if (opt_loops)
        jd->ld    = new MethodLoopData;
#endif

    /* Allocate codeinfo memory from the heap as we need to keep them. */

    code = code_codeinfo_new(m);

    /* Set codeinfo flags. */

    if (checksync && (m->flags & ACC_SYNCHRONIZED))
        code_flag_synchronized(code);

    if (checksync && (m->flags & ACC_SYNCHRONIZED))
        code_unflag_leafmethod(code);
    else
        code_flag_leafmethod(code);

    /* initialize variables */

    jd->code                 = code;
    jd->flags                = 0;
    jd->exceptiontable       = NULL;
    jd->exceptiontablelength = 0;
    jd->returncount          = 0;
    jd->branchtoentry        = false;
    jd->branchtoend          = false;
    jd->returncount          = 0;
    jd->returnblock          = NULL;
    jd->maxlocals            = m->maxlocals;

    return jd;
}

STAT_REGISTER_VAR_EXTERN(std::size_t, compiler_last_codesize, 0, "last-code-size", "code size of the last compiled method")

/* jit_compile *****************************************************************

   Translates one method to machine code.

*******************************************************************************/

static u1 *jit_compile_intern(jitdata *jd);

u1 *jit_compile(methodinfo *m)
{
    u1      *r;
    jitdata *jd;

    STATISTICS(count_jit_calls++);

    /* Initialize the static function's class. */

    /* ATTENTION: This MUST be done before the method lock is aquired,
       otherwise we could run into a deadlock with <clinit>'s that
       call static methods of it's own class. */

    if ((m->flags & ACC_STATIC) && !(m->clazz->state & CLASS_INITIALIZED)) {
#if !defined(NDEBUG)
        if (initverbose)
            log_message_class("Initialize class ", m->clazz);
#endif

        if (!initialize_class(m->clazz))
            return NULL;

        /* check if the method has been compiled during initialization */

        if ((m->code != NULL) && (m->code->entrypoint != NULL))
            return m->code->entrypoint;
    }

    /* enter a monitor on the method */

    m->mutex->lock();

    /* if method has been already compiled return immediately */

    if (m->code != NULL) {
        m->mutex->unlock();

        assert(m->code->entrypoint);
        return m->code->entrypoint;
    }

    TRACECOMPILERCALLS();

    STATISTICS(count_methods++);

#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_start();
#endif

    // Create new dump memory area.
    DumpMemoryArea dma;

    /* create jitdata structure */

    jd = jit_jitdata_new(m);

    /* set the flags for the current JIT run */

    jd->flags = JITDATA_FLAG_PARSE;

#if defined(ENABLE_VERIFIER)
    if (opt_verify)
        jd->flags |= JITDATA_FLAG_VERIFY;
#endif

#if defined(ENABLE_PROFILING)
    if (opt_prof)
        jd->flags |= JITDATA_FLAG_INSTRUMENT;
#endif

#if defined(ENABLE_IFCONV)
    if (opt_ifconv)
        jd->flags |= JITDATA_FLAG_IFCONV;
#endif

#if defined(ENABLE_INLINING) && defined(ENABLE_INLINING_DEBUG)
    if (opt_Inline && opt_InlineAll)
        jd->flags |= JITDATA_FLAG_INLINE;
#endif

    if (opt_showintermediate)
        jd->flags |= JITDATA_FLAG_SHOWINTERMEDIATE;

    if (opt_showdisassemble)
        jd->flags |= JITDATA_FLAG_SHOWDISASSEMBLE;

    if (opt_verbosecall)
        jd->flags |= JITDATA_FLAG_VERBOSECALL;

#if defined(ENABLE_COMPILER2)
    if (!opt_DisableCountdownTraps && (opt_ReplaceMethod == NULL || method_matches(m, opt_ReplaceMethod)))
        jd->flags |= JITDATA_FLAG_COUNTDOWN;
#endif

#if defined(ENABLE_JIT)
# if defined(ENABLE_INTRP)
    if (!opt_intrp)
# endif
        /* initialize the register allocator */
    {
        reg_setup(jd);
    }
#endif

    /* setup the codegendata memory */

    codegen_setup(jd);

    /* now call internal compile function */

    r = jit_compile_intern(jd);
#if defined(ENABLE_COMPILER2)
    if (method_matches(m,opt_CompileMethod)) {
        using namespace cacao::jit::compiler2;
        JITData JD(jd);
        ObjectFileWriterPass pass;
        pass.initialize();
        pass.run(JD);
        pass.finalize();
    }
#endif

    if (r == NULL) {
        /* We had an exception! Finish stuff here if necessary. */

        /* release codeinfo */

        code_codeinfo_free(jd->code);
    }
    else {
        DEBUG_JIT_COMPILEVERBOSE("Running: ");
    }

#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_stop();
#endif

    // Hook point just after code was generated.
    Hook::jit_generated(m, m->code);

    /* leave the monitor */

    m->mutex->unlock();

#if defined(ENABLE_STATISTICS)
    if (m && m->code)
        compiler_last_codesize = m->code->mcodelength;
#endif

    /* return pointer to the methods entry point */

    return r;
}


/* jit_jitdata_init_for_recompilation ******************************************

   Initalizes a jitdata structure such that it can be used for rompiling a
   method.

*******************************************************************************/

void jit_jitdata_init_for_recompilation(jitdata *jd) {
    /* get the optimization flags for the current JIT run */

#if defined(ENABLE_VERIFIER)
    jd->flags |= JITDATA_FLAG_VERIFY;
#endif

    if (opt_showintermediate)
        jd->flags |= JITDATA_FLAG_SHOWINTERMEDIATE;
    if (opt_showdisassemble)
        jd->flags |= JITDATA_FLAG_SHOWDISASSEMBLE;
    if (opt_verbosecall)
        jd->flags |= JITDATA_FLAG_VERBOSECALL;

#if defined(ENABLE_JIT)
# if defined(ENABLE_INTRP)
    if (!opt_intrp)
# endif
        /* initialize the register allocator */

        reg_setup(jd);
#endif

    /* setup the codegendata memory */

    codegen_setup(jd);
}


/* jit_recompile ***************************************************************

   Recompiles a Java method.

*******************************************************************************/

u1 *jit_recompile(methodinfo *m)
{
    DEBUG_JIT_COMPILEVERBOSE("Recompiling start: ");

#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_start();
#endif

    /* Create new dump memory area. */

    DumpMemoryArea dma;

    /* create jitdata structure */

    jitdata *jd = jit_jitdata_new(m);
    jit_jitdata_init_for_recompilation(jd);

    /* set the current optimization level to the previous one plus 1 */

    u1 optlevel = (jd->m->code) ? jd->m->code->optlevel : 0;
    jd->code->optlevel = optlevel + 1;

    /* now call internal compile function */

    u1 *entrypoint = jit_compile_intern(jd);

    if (entrypoint == NULL) {
        /* We had an exception! Finish stuff here if necessary. */

        /* release codeinfo */

        code_codeinfo_free(jd->code);
    }

#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_stop();
#endif

    // Hook point just after code was generated.
    Hook::jit_generated(m, m->code);

    DEBUG_JIT_COMPILEVERBOSE("Recompiling done: ");

    /* return pointer to the methods entry point */

    return entrypoint;
}


/* jit_recompile_for_deoptimization ********************************************

   Recompiles a Java method generating necessary meta-data for deoptimization.

*******************************************************************************/

u1 *jit_recompile_for_deoptimization(methodinfo *m)
{
#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_start();
#endif

    /* Create new dump memory area. */

    DumpMemoryArea dma;

    /* create jitdata structure */

    jitdata *jd = jit_jitdata_new(m);
    jit_jitdata_init_for_recompilation(jd);

    jd->flags |= JITDATA_FLAG_DEOPTIMIZE;

    /* now call internal compile function */

    u1 *entrypoint = jit_compile_intern(jd);

    if (entrypoint == NULL) {
        /* We had an exception! Finish stuff here if necessary. */

        /* release codeinfo */

        code_codeinfo_free(jd->code);
    }

#if defined(ENABLE_STATISTICS)
    /* measure time */

    if (opt_getcompilingtime)
        compilingtime_stop();
#endif

    // Hook point just after code was generated.
    Hook::jit_generated(m, m->code);

    /* return pointer to the methods entry point */

    return entrypoint;
}


#if defined(ENABLE_PM_HACKS)
#include "vm/jit/jit_pm_1.inc"
#endif

// register compiler real-time group
RT_REGISTER_GROUP(compiler_group,"compiler","baseline compiler")

// register real-time timers
RT_REGISTER_GROUP_TIMER(checks_timer,        "compiler","checks at beginning",          compiler_group)
RT_REGISTER_GROUP_TIMER(parse_timer,         "compiler","parse",                        compiler_group)
RT_REGISTER_GROUP_TIMER(stack_timer,         "compiler","analyse_stack",                compiler_group)
RT_REGISTER_GROUP_TIMER(typechecker_timer,   "compiler","typecheck",                    compiler_group)
RT_REGISTER_GROUP_TIMER(loop_timer,          "compiler","loop",                         compiler_group)
RT_REGISTER_GROUP_TIMER(ifconversion_timer,  "compiler","if conversion",                compiler_group)
RT_REGISTER_GROUP_TIMER(ra_timer,            "compiler","register allocation",          compiler_group)
RT_REGISTER_GROUP_TIMER(codegen_timer,       "compiler","codegen",                      compiler_group)

/* jit_compile_intern **********************************************************

   Static internal function which does the actual compilation.

*******************************************************************************/

static u1 *jit_compile_intern(jitdata *jd)
{
    methodinfo  *m;
    //codegendata *cd;
    codeinfo    *code;

    RT_TIMER_START(checks_timer);

    /* get required compiler data */

#if defined(ENABLE_LSRA) || defined(ENABLE_SSA)
    jd->ls = NULL;
#endif
    m    = jd->m;
    code = jd->code;
    //cd   = jd->cd;

#if defined(ENABLE_DEBUG_FILTER)
    show_filters_apply(jd->m);
#endif

    // Handle native methods and create a native stub.
    if (m->flags & ACC_NATIVE) {
        NativeMethods& nm = VM::get_current()->get_nativemethods();
        void* f = nm.resolve_method(m);

        if (f == NULL)
            return NULL;

        // XXX reinterpret_cast is used to prevend a compiler warning
        // The Native* framework requires a rework to make it type safer
        // and to get rid of this hack
        code = NativeStub::generate(m, *reinterpret_cast<functionptr*>(&f));

        /* Native methods are never recompiled. */

        assert(!m->code);

        m->code = code;

        return code->entrypoint;
    }

    /* if there is no javacode, print error message and return empty method   */

    if (m->jcode == NULL) {
        DEBUG_JIT_COMPILEVERBOSE("No code given for: ");

        code->entrypoint = (u1 *) (ptrint) do_nothing_function;
        m->code = code;

        return code->entrypoint;        /* return empty method                */
    }

    STATISTICS(count_javacodesize += m->jcodelength + 18);
    STATISTICS(count_tryblocks    += jd->exceptiontablelength);
    STATISTICS(count_javaexcsize  += jd->exceptiontablelength * SIZEOF_VOID_P);

    RT_TIMER_STOPSTART(checks_timer,parse_timer);

#if defined(WITH_JAVA_RUNTIME_LIBRARY_OPENJDK)
    /* Code for Sun's OpenJDK (see
       hotspot/src/share/vm/classfile/verifier.cpp
       (Verifier::is_eligible_for_verification)): Don't verify
       dynamically-generated bytecodes. */

# if defined(ENABLE_VERIFIER)
    if (class_issubclass(m->clazz, class_sun_reflect_MagicAccessorImpl))
        jd->flags &= ~JITDATA_FLAG_VERIFY;
# endif
#endif

    /* call the compiler passes ***********************************************/

    DEBUG_JIT_COMPILEVERBOSE("Parsing: ");

    /* call parse pass */

    if (!parse(jd)) {
        DEBUG_JIT_COMPILEVERBOSE("Exception while parsing: ");

        return NULL;
    }
    RT_TIMER_STOP(parse_timer);

    DEBUG_JIT_COMPILEVERBOSE("Parsing done: ");

#if defined(ENABLE_JIT)
# if defined(ENABLE_INTRP)
    if (!opt_intrp) {
# endif
        RT_TIMER_START(stack_timer);
        DEBUG_JIT_COMPILEVERBOSE("Analysing: ");

        /* call stack analysis pass */

        if (!stack_analyse(jd)) {
            DEBUG_JIT_COMPILEVERBOSE("Exception while analysing: ");

            return NULL;
        }
        RT_TIMER_STOPSTART(stack_timer,typechecker_timer);

        DEBUG_JIT_COMPILEVERBOSE("Analysing done: ");

#ifdef ENABLE_VERIFIER
        if (JITDATA_HAS_FLAG_VERIFY(jd)) {
            DEBUG_JIT_COMPILEVERBOSE("Typechecking: ");

            /* call typecheck pass */
            if (!typecheck(jd)) {
                DEBUG_JIT_COMPILEVERBOSE("Exception while typechecking: ");

                return NULL;
            }

            DEBUG_JIT_COMPILEVERBOSE("Typechecking done: ");
        }
#endif
        RT_TIMER_STOPSTART(typechecker_timer,loop_timer);

#if defined(ENABLE_IFCONV)
        if (JITDATA_HAS_FLAG_IFCONV(jd)) {
            if (!ifconv_static(jd))
                return NULL;
            jit_renumber_basicblocks(jd);
        }
#endif
        RT_TIMER_STOPSTART(ifconversion_timer,ra_timer);

        /* inlining */

#if defined(ENABLE_INLINING) && (!defined(ENABLE_ESCAPE) || 1)
        if (JITDATA_HAS_FLAG_INLINE(jd)) {
            if (!inline_inline(jd))
                return NULL;
        }
#endif

#if defined(ENABLE_SSA)
        if (opt_lsra) {
            fix_exception_handlers(jd);
        }
#endif

        /* Build the CFG.  This has to be done after stack_analyse, as
           there happens the JSR elimination. */

        if (!cfg_build(jd))
            return NULL;

#if defined(ENABLE_LOOP)
        if (opt_loops)
        {
            removeArrayBoundChecks(jd);
            jit_renumber_basicblocks(jd);
            
            cfg_clear(jd);
            if (!cfg_build(jd))
                return NULL;
        }
#endif
        RT_TIMER_STOPSTART(ra_timer,loop_timer);

#if defined(ENABLE_PROFILING)
        /* Basic block reordering.  I think this should be done after
           if-conversion, as we could lose the ability to do the
           if-conversion. */

        if (JITDATA_HAS_FLAG_REORDER(jd)) {
            if (!reorder(jd))
                return NULL;
            jit_renumber_basicblocks(jd);
        }
#endif

#if defined(ENABLE_PM_HACKS)
#include "vm/jit/jit_pm_2.inc"
#endif
        DEBUG_JIT_COMPILEVERBOSE("Allocating registers: ");

#if defined(ENABLE_LSRA) && !defined(ENABLE_SSA)
        /* allocate registers */
        if (opt_lsra) {
            if (!lsra(jd))
                return NULL;

            STATISTICS(count_methods_allocated_by_lsra++);

        } else
# endif /* defined(ENABLE_LSRA) && !defined(ENABLE_SSA) */
#if defined(ENABLE_SSA)
        /* allocate registers */
        if (
            (opt_lsra &&
            jd->code->optlevel > 0)
            /* strncmp(UTF_TEXT(jd->m->name), "hottie", 6) == 0*/
            /*&& jd->exceptiontablelength == 0*/
        ) {
            /*printf("=== %s ===\n", UTF_TEXT(jd->m->name));*/
            jd->ls = (lsradata*) DumpMemory::allocate(sizeof(lsradata));
            jd->ls = NULL;
            ssa(jd);
            /*lsra(jd);*/ regalloc(jd);
            /*eliminate_subbasicblocks(jd);*/
            STATISTICS(count_methods_allocated_by_lsra++);

        } else
# endif /* defined(ENABLE_SSA) */
        {
            STATISTICS(count_locals_conflicts += (jd->maxlocals - 1) * (jd->maxlocals));

            regalloc(jd);
        }

        STATISTICS(simplereg_make_statistics(jd));

        RT_TIMER_STOP(ra_timer);
        DEBUG_JIT_COMPILEVERBOSE("Allocating registers done: ");
# if defined(ENABLE_INTRP)
    }
# endif
#endif /* defined(ENABLE_JIT) */
    RT_TIMER_START(codegen_timer);

#if defined(ENABLE_PROFILING)
    /* Allocate memory for basic block profiling information. This
       _must_ be done after loop optimization and register allocation,
       since they can change the basic block count. */

    if (JITDATA_HAS_FLAG_INSTRUMENT(jd)) {
        code->basicblockcount = jd->basicblockcount;
        code->bbfrequency = MNEW(u4, jd->basicblockcount);
    }
#endif

    DEBUG_JIT_COMPILEVERBOSE("Generating code: ");

    /* now generate the machine code */

#if defined(ENABLE_JIT)
# if defined(ENABLE_INTRP)
    if (opt_intrp) {
#if defined(ENABLE_VERIFIER)
        if (opt_verify) {
            DEBUG_JIT_COMPILEVERBOSE("Typechecking (stackbased): ");

            if (!typecheck_stackbased(jd)) {
                DEBUG_JIT_COMPILEVERBOSE("Exception while typechecking (stackbased): ");
                return NULL;
            }
        }
#endif
        if (!intrp_codegen(jd)) {
            DEBUG_JIT_COMPILEVERBOSE("Exception while generating code: ");

            return NULL;
        }
    } else
# endif
        {
            if (!codegen_generate(jd)) {
                DEBUG_JIT_COMPILEVERBOSE("Exception while generating code: ");

                return NULL;
            }
        }
#else
    if (!intrp_codegen(jd)) {
        DEBUG_JIT_COMPILEVERBOSE("Exception while generating code: ");

        return NULL;
    }
#endif
    RT_TIMER_STOP(codegen_timer);

    DEBUG_JIT_COMPILEVERBOSE("Generating code done: ");

#if !defined(NDEBUG)
#if defined(ENABLE_DEBUG_FILTER)
    if (jd->m->filtermatches & SHOW_FILTER_FLAG_SHOW_METHOD)
#endif
    {
        /* intermediate and assembly code listings */

        if (JITDATA_HAS_FLAG_SHOWINTERMEDIATE(jd)) {
            show_method(jd, SHOW_CODE);
        }
        else if (JITDATA_HAS_FLAG_SHOWDISASSEMBLE(jd)) {
# if defined(ENABLE_DISASSEMBLER)
            DISASSEMBLE(code->entrypoint,
                        code->entrypoint + (code->mcodelength - jd->cd->dseglen));
# endif
        }

        if (opt_showddatasegment)
            dseg_display(jd);
    }
#endif

    /* switch to the newly generated code */

    assert(code);
    assert(code->entrypoint);

    /* add the current compile version to the methodinfo */

    code->prev = m->code;
    m->code = code;

    /* return pointer to the methods entry point */

    return code->entrypoint;
}


/* jit_invalidate_code *********************************************************

   Mark the compiled code of the given method as invalid and take care that
   it is replaced if necessary.

   XXX Not fully implemented, yet.

*******************************************************************************/

void jit_invalidate_code(methodinfo *m)
{
    codeinfo *code;

    code = m->code;

    if (code == NULL || code_is_invalid(code))
        return;

    code_flag_invalid(code);

    /* activate mappable replacement points */

#if defined(ENABLE_COMPILER2)
    replace_activate_replacement_points(code, true);
#else
    vm_abort("invalidating code only works with ENABLE_COMPILER2");
#endif
}


/* jit_request_optimization ****************************************************

   Request optimization of the given method. If the code of the method is
   unoptimized, it will be invalidated, so the next jit_get_current_code(m)
   triggers an optimized recompilation.
   If the method is already optimized, this function does nothing.

   IN:
       m................the method

*******************************************************************************/

void jit_request_optimization(methodinfo *m)
{
    codeinfo *code;

    code = m->code;

    if (code && code->optlevel == 0)
        jit_invalidate_code(m);
}


/* jit_get_current_code ********************************************************

   Get the currently valid code for the given method. If there is no valid
   code, (re)compile the method.

   IN:
       m................the method

   RETURN VALUE:
       the codeinfo* for the current code, or
       NULL if an exception has been thrown during recompilation.

*******************************************************************************/

codeinfo *jit_get_current_code(methodinfo *m)
{
    assert(m);

    /* if we have valid code, return it */

    if (m->code && !code_is_invalid(m->code))
        return m->code;

    /* otherwise: recompile */

#if defined(ENABLE_COMPILER2)
    if (!cacao::jit::compiler2::compile(m))
        return NULL;
#else
    if (!jit_recompile(m))
        return NULL;
#endif

    assert(m->code);

    return m->code;
}


/* jit_asm_compile *************************************************************

   This method is called from asm_vm_call_method and does:

     - create stackframe info for exceptions
     - compile the method
     - patch the entrypoint of the method into the calculated address in
       the JIT code
     - flushes the instruction cache.

*******************************************************************************/

#if defined(ENABLE_JIT)
#if !defined(JIT_COMPILER_VIA_SIGNAL)
extern "C" {
void* jit_asm_compile(methodinfo *m, void* mptr, void* sp, void* ra)
{
    stackframeinfo_t  sfi;
    void             *entrypoint;
    void             *pa;
    uintptr_t        *p;

    /* create the stackframeinfo (subtract 1 from RA as it points to the */
    /* instruction after the call)                                       */

    stacktrace_stackframeinfo_add(&sfi, NULL, sp, ra, ((uint8_t*) ra) - 1);

    /* actually compile the method */

    entrypoint = jit_compile(m);

    /* remove the stackframeinfo */

    stacktrace_stackframeinfo_remove(&sfi);

    /* there was a problem during compilation */

    if (entrypoint == NULL)
        return NULL;

    /* get the method patch address */

    pa = md_jit_method_patch_address(sfi.pv, (void *) ra, mptr);

    /* patch the method entry point */

    p = (uintptr_t*) pa;

    *p = (uintptr_t) entrypoint;

    /* flush the instruction cache */

    md_icacheflush(pa, SIZEOF_VOID_P);

    return entrypoint;
}
}
#endif

/* jit_compile_handle **********************************************************

   This method is called from the appropriate signal handler which
   handles compiler-traps and does the following:

     - compile the method
     - patch the entrypoint of the method into the calculated address in
       the JIT code
     - flush the instruction cache

*******************************************************************************/

void *jit_compile_handle(methodinfo *m, void *pv, void *ra, void *mptr)
{
    void      *newpv;                               /* new compiled method PV */
    void      *pa;                                           /* patch address */
    uintptr_t *p;                                      /* convenience pointer */

    /* Compile the method. */

    bool compile_optimized = false;
#if defined(ENABLE_COMPILER2)
    compile_optimized = method_matches(m,opt_OptimizeMethod);
#endif

    if (compile_optimized) {
#if defined(ENABLE_COMPILER2)
        newpv = cacao::jit::compiler2::compile(m);
#endif
    } else {
        newpv = jit_compile(m);
    }

    /* There was a problem during compilation. */

    if (newpv == NULL)
        return NULL;

    /* Get the method patch address. */

    pa = md_jit_method_patch_address(pv, ra, mptr);

    /* Patch the method entry point. */

    p = (uintptr_t *) pa;

    *p = (uintptr_t) newpv;

    /* Flush both caches. */

    md_cacheflush(pa, SIZEOF_VOID_P);

    return newpv;
}
#endif /* defined(ENABLE_JIT) */


/* jit_complement_condition ****************************************************

   Returns the complement of the passed conditional instruction.

   We use the order of the different conditions, e.g.:

   ICMD_IFEQ         153
   ICMD_IFNE         154

   If the passed opcode is odd, we simply add 1 to get the complement.
   If the opcode is even, we subtract 1.

   Exception:

   ICMD_IFNULL       198
   ICMD_IFNONNULL    199

*******************************************************************************/

ICMD jit_complement_condition(ICMD opcode)
{
    switch (opcode) {
    case ICMD_IFNULL:
        return ICMD_IFNONNULL;

    case ICMD_IFNONNULL:
        return ICMD_IFNULL;

    default:
        /* check if opcode is odd */

        if (opcode & 0x1)
            return ICMD(opcode + 1);
        else
            return ICMD(opcode - 1);
    }
}


/* jit_renumber_basicblocks ****************************************************

   Set the ->nr of all blocks so it increases when traversing ->next.

   IN:
       jitdata..........the current jitdata

*******************************************************************************/

void jit_renumber_basicblocks(jitdata *jd)
{
    s4          nr;
    basicblock *bptr;

    nr = 0;
    for (bptr = jd->basicblocks; bptr != NULL; bptr = bptr->next) {
        bptr->nr = nr++;
    }

    /* we have one block more than jd->basicblockcount (the end marker) */

    assert(nr == jd->basicblockcount + 1);
}


/* jit_check_basicblock_numbers ************************************************

   Assert that the ->nr of the first block is zero and increases by 1 each
   time ->next is traversed.
   This function should be called before any analysis that relies on
   the basicblock numbers.

   IN:
       jitdata..........the current jitdata

   NOTE: Aborts with an assertion if the condition is not met!

*******************************************************************************/

#if !defined(NDEBUG)
void jit_check_basicblock_numbers(jitdata *jd)
{
    s4          nr;
    basicblock *bptr;

    nr = 0;
    for (bptr = jd->basicblocks; bptr != NULL; bptr = bptr->next) {
        assert(bptr->nr == nr);
        nr++;
    }

    /* we have one block more than jd->basicblockcount (the end marker) */

    assert(nr == jd->basicblockcount + 1);
}
#endif /* !defined(NDEBUG) */


/*
 * 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:
 */