md-os.cpp

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/* src/vm/jit/sparc64/solaris/md-os.cpp - machine dependent SPARC Solaris functions

   Copyright (C) 1996-2013
   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 "config.h"

#include <cassert>
#include <stdint.h>
#include <ucontext.h>

/* work around name clash */
#undef REG_SP

#include "vm/types.hpp"

#include "vm/jit/sparc64/codegen.hpp"
#include "vm/jit/sparc64/md-abi.hpp"

#include "vm/signallocal.hpp"

#include "vm/jit/asmpart.hpp"
#include "vm/jit/stacktrace.hpp"
#include "vm/jit/trap.hpp"


ptrint md_get_reg_from_context(mcontext_t *_mc, u4 rindex)
{
    ptrint val; 
    s8     *window;
    
    
    /* return 0 for REG_ZERO */
    
    if (rindex == 0)
        return 0;
        
    
    if (rindex <= 15) {
        
        /* register is in global or out range, available in context */
        val = _mc->gregs[rindex + 3];
        
    }
    else {
        assert(rindex <= 31);
        
        /* register is local or in, need to fetch from regsave area on stack */

        window = (s8 *) (_mc->gregs[REG_O6] + BIAS);
        val = window[rindex - 16];

    }
    
    return val;
}


/* md_signal_handler_sigsegv ***************************************************

   NullPointerException signal handler for hardware null pointer
   check.

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

void md_signal_handler_sigsegv(int sig, siginfo_t *siginfo, void *_p)
{
    ucontext_t     *_uc;
    mcontext_t     *_mc;
    ptrint          addr;
    u1             *pv;
    u1             *sp;
    u1             *ra;
    u1             *xpc;
    u4              mcode;
    int             d;
    int             s1;
    int16_t         disp;
    intptr_t        val;
    int             type;
    void           *p;

    _uc = (ucontext_t *) _p;
    _mc = &_uc->uc_mcontext;

    pv  = (u1 *) md_get_reg_from_context(_mc, REG_PV_CALLEE);
    sp  = (u1 *) _mc->gregs[REG_O6];
    ra  = (u1 *) md_get_reg_from_context(_mc, REG_RA_CALLEE);
    xpc = (u1 *) _mc->gregs[REG_PC];


    /* get exception-throwing instruction */    

    mcode = *((u4 *) xpc);

    d    = M_OP3_GET_RD(mcode);
    s1   = M_OP3_GET_RS(mcode);
    disp = M_OP3_GET_IMM(mcode);

    /* flush register windows? */
    
    val  = md_get_reg_from_context(_mc, d);

    /* check for special-load */

    if (s1 == REG_ZERO) {
        /* we use the exception type as load displacement */

        type = disp;
    }
    else {
        /* This is a normal NPE: addr must be NULL and the NPE-type
           define is 0. */

        addr = md_get_reg_from_context(_mc, s1);
        type = (int) addr;
    }

    /* Handle the trap. */

    p = trap_handle(type, val, pv, sp, ra, xpc, _p);

    /* Set registers. */

    _mc->gregs[REG_G2]  = (uintptr_t) p;                    /* REG_ITMP2_XPTR */
    _mc->gregs[REG_G3]  = (uintptr_t) xpc;                   /* REG_ITMP3_XPC */
    _mc->gregs[REG_PC]  = (uintptr_t) asm_handle_exception;
    _mc->gregs[REG_nPC] = (uintptr_t) asm_handle_exception + 4; 
}


/* md_icacheflush **************************************************************

   Calls the system's function to flush the instruction cache.

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

void md_icacheflush(u1 *addr, s4 nbytes)
{
    u1* end;
    
    end = addr + nbytes;
    
    /* zero the least significant 3 bits to align on a 64-bit boundary */
    addr = (u1 *) (((ptrint) addr) & -8l);
    
    while (addr < end) {
        __asm__ (
            "flush %0"
            :
            : "r"(addr)
            );
        addr += 8;
    }
}




/*
 * 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:
 */