Subversion Repositories tendra.SVN

/*

 * Copyright (c) 2002-2005 The TenDRA Project <http://www.tendra.org/>.

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are met:

 *

 * 1. Redistributions of source code must retain the above copyright notice,

 *    this list of conditions and the following disclaimer.

 * 2. 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.

 * 3. Neither the name of The TenDRA Project 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 HOLDERS 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.

 *

 * $Id$

 */

/*

    		 Crown Copyright (c) 1997

    This TenDRA(r) Computer Program is subject to Copyright

    owned by the United Kingdom Secretary of State for Defence

    acting through the Defence Evaluation and Research Agency

    (DERA).  It is made available to Recipients with a

    royalty-free licence for its use, reproduction, transfer

    to other parties and amendment for any purpose not excluding

    product development provided that any such use et cetera

    shall be deemed to be acceptance of the following conditions:-

        (1) Its Recipients shall ensure that this Notice is

        reproduced upon any copies or amended versions of it;

        (2) Any amended version of it shall be clearly marked to

        show both the nature of and the organisation responsible

        for the relevant amendment or amendments;

        (3) Its onward transfer from a recipient to another

        party shall be deemed to be that party's acceptance of

        these conditions;

        (4) DERA gives no warranty or assurance as to its

        quality or suitability for any purpose and DERA accepts

        no liability whatsoever in relation to any use to which

        it may be put.

*/

/*

			    VERSION INFORMATION

			    ===================

--------------------------------------------------------------------------

$Header: /u/g/release/CVSROOT/Source/src/installers/680x0/common/codex.c,v 1.1.1.1 1998/01/17 15:55:49 release Exp $

--------------------------------------------------------------------------

$Log: codex.c,v $

 * Revision 1.1.1.1  1998/01/17  15:55:49  release

 * First version to be checked into rolling release.

 *

Revision 1.2  1997/10/29 10:22:08  ma

Replaced use_alloca with has_alloca.

Revision 1.1.1.1  1997/10/13 12:42:49  ma

First version.

Revision 1.6  1997/10/13 08:49:04  ma

Made all pl_tests for general proc & exception handling pass.

Revision 1.5  1997/09/25 06:44:55  ma

All general_proc tests passed

Revision 1.4  1997/06/18 12:04:50  ma

Merged with Input Baseline changes.

Revision 1.3  1997/06/18 10:09:26  ma

Checking in before merging with Input Baseline changes.

Revision 1.2  1997/04/20 11:30:21  ma

Introduced gcproc.c & general_proc.[ch].

Added cases for apply_general_proc next to apply_proc in all files.

Revision 1.1.1.1  1997/03/14 07:50:11  ma

Imported from DRA

 * Revision 1.1.1.1  1996/09/20  10:56:53  john

 *

 * Revision 1.2  1996/07/05  14:18:40  john

 * Changes for spec 3.1

 *

 * Revision 1.1.1.1  1996/03/26  15:45:09  john

 *

 * Revision 1.3  94/02/21  15:56:50  15:56:50  ra (Robert Andrews)

 * A couple of flags which used to be bool are now int.

 *

 * Revision 1.2  93/05/24  15:54:51  15:54:51  ra (Robert Andrews)

 * Don't recognise alloca by its tag name, but by its token name.

 *

 * Revision 1.1  93/02/22  17:15:25  17:15:25  ra (Robert Andrews)

 * Initial revision

 *

--------------------------------------------------------------------------

*/

#include "config.h"

#include "common_types.h"

#include "assembler.h"

#include "basicread.h"

#include "check.h"

#include "expmacs.h"

#include "exptypes.h"

#include "exp.h"

#include "flags.h"

#include "instrs.h"

#include "installglob.h"

#include "shapemacs.h"

#include "flpt.h"

#include "evaluate.h"

#include "externs.h"

#include "install_fns.h"

#include "mach.h"

#include "mach_ins.h"

#include "mach_op.h"

#include "peephole.h"

#include "codex.h"

#include "output.h"

#include "tags.h"

#include "tests.h"

#include "utility.h"

#include "where.h"

#include "coder.h"

#include "operations.h"

#include "ops_shared.h"

#include "translate.h"

#include "codec.h"

#include "install_fns.h"

#if have_diagnostics

#include "xdb_basics.h"

#include "xdb_types.h"

#include "xdb_output.h"

#endif

#ifndef tdf3

#include "general_proc.h"

#include "68k_globals.h"

#endif

extern bool have_cond;

extern int do_peephole;

extern int do_pic;

extern ast add_shape_to_stack(ash, shape);

/*

    SELECT BYTE, WORD OR LONG INSTRUCTION

    opb, opw and opl give the byte, word and long versions of an instruction.

    The appropriate instruction for size sz is returned.

*/

int ins

(long sz, int opb, int opw, int opl)

{

    if (sz <= 8) return(opb);

    if (sz <= 16) return(opw);

    if (sz <= 32) return(opl);

    error("Illegal instruction size");

    return(opl);

}

/*

    SELECT SINGLE OR DOUBLE FLOATING-POINT INSTRUCTION

    ops and opd give the single and double precision versions of an

    instruction.  The appropriate instruction for size sz is returned.

*/

int insf

(long sz, int ops, int opd, int opx)

{

    if (sz == 32) return(ops);

    if (sz == 64) return(opd);

    error("Illegal instruction size");

    return(opx);

}

/*

    ADD A CONSTANT TO AN ADDRESS REGISTER

    This routine is used primarily for updating the stack.  It adds d

    to the A-register with number r.

*/

void add_to_reg

(int r, long d)

{

    if (d) {

	int instr;

	mach_op *op1;

	mach_op *op2 = make_register(r);

	if (d > 0 && d <= 8) {

	    instr = m_addql;

	    op1 = make_value(d);

	} else if (d < 0 && d >= -8) {

	    instr = m_subql;

	    op1 = make_value(-d);

	} else {

	    instr = m_lea;

	    op1 = make_indirect(r, d);

	}

	make_instr(instr, op1, op2, regmsk(r));

	have_cond = 0;

    }

    return;

}

/*

    CHECK RESERVED NAMES

    This routine returns 1 if nm is a name reserved by the linker.

*/

bool reserved

(char *nm)

{

    int i;

    static char *rn[] = {

	"_edata", "_etext", "_end", "__edata", "__etext", "__end"

    };

    for (i = 0; i < array_size(rn); i++) {

	if (eq(nm, rn[i])) return(1);

    }

    return(0);

}

/*

    LOOK FOR SPECIAL FUNCTIONS

    An expression is examined to see if it is a recognised special

    function.  The functions recognised are : strcpy of a constant

    string (which is turned into a move instruction), and alloca

    (which is inlined).

*/

speci special_fn

(exp a1, exp a2, shape s)

{

    speci spec_fn;

    dec *d = brog(son(a1));

    char *id = d->dec_u.dec_val.dec_id;

    spec_fn.is_special = 0;

    if (id == null) return(spec_fn);

    if (eq(id, "_setjmp"))has_setjmp = 1;

    if (eq(id, "_longjmp"))has_setjmp = 1;

    if (!do_alloca) return(spec_fn);

    if ( ( /* eq ( id, "_alloca" ) || */ eq ( id, "___builtin_alloca" ) ) &&

	 a2 != nilexp && last(a2)) {

	exp r = getexp(s, nilexp, 0, a2, nilexp, 0, L0, alloca_tag);

	setfather(r, son(r));

	has_alloca = 1;

	spec_fn.is_special = 1;

	spec_fn.special_exp = r;

	kill_exp(a1, a1);

	return(spec_fn);

    }

    return(spec_fn);

}

/*

    STACK INFORMATION

    A number of variable are used to represent the state of the stack.

    used_stack is true to indicate that space has been allocated for

    variables on the stack or that alloca is used in the current

    procedure (the latter is also indicated by has_alloca) or that

    we are in diagnostics mode.  It forces the use of the application

    pointer instead of the stack pointer.  max_stack gives the amount

    of space allocated on the stack.

    stack_dec and stack_size are both used to keep track of changes

    to the stack pointer due to pushes and pops etc.

    extra_stack is used in coder for working out the position of

    procedure arguments which are compound results of procedure calls.

    ldisp is the extra value which needs to be added to the stack pointer

    to reference procedure arguments.  Its value is not known until the

    entire procedure has been coded, so a special label is used to

    represent its value during the procedure coding.  used_ldisp is

    true to indicate that this special label has been used.

*/

bool used_stack = 0;

long max_stack = 0;

long stack_dec = 0;

long stack_size = 0;

long extra_stack = 0;

bool used_ldisp = 0;

long ldisp = 0;

/*

    PENDING STACK DISPLACEMENT

    Consecutive changes to the stack pointer are combined whenever

    possible.  stack_change gives the current amount of change which

    has not been output as an instruction.

*/

long stack_change = 0;

int stack_direction = 0;

/*

    DECREASE THE STACK

    This routine decreases the stack pointer by d bits.

*/

void dec_stack

(long d)

{

    if (d) {

	stack_change -= d;

	stack_direction = (d > 0 ? 1 : 0);

	have_cond = 0;

#ifdef EBUG

        update_stack();

#endif

    }

    return;

}

/*

    OUTPUT STACK DISPLACEMENT

    This routine outputs any accummulated stack changes.

*/

void update_stack

(void)

{

    if (stack_change) {

	long d = stack_change / 8;

	stack_size += stack_change;

	stack_change = 0;

	add_to_reg(REG_SP, d);

    }

    return;

}

/*

    CHANGE DATA AREA

    This routine changes the current address area.  p can be one of

    the values ptext, pdata or pbss given in codex.h.

*/

void area

(int p)

{

    static int current_area = -1;

    static int previous_area = -1;

    if (p == plast)p = previous_area;

    if (p != current_area) {

	int i;

	switch (p) {

	    case ptext: i = m_as_text; break;

	    case pdata: i = m_as_data; break;

	    case pbss: i = m_as_bss; break;

	    default : i = m_dont_know; break;

	}

	make_instr(i, null, null, 0);

	previous_area = current_area;

	current_area = p;

    } else {

	previous_area = current_area;

    }

    return;

}

/*

    OUTPUT A LIBRARY CALL

    A call of the library routine with name nm is output.

*/

void libcall

(char *nm)

{

    int lab;

    mach_op *p = make_extern_data(nm, 0);

#if 0 /*float_to_unsigned*/

    if ((have_overflow() || have_continue()) && !strcmp(nm,float_to_unsigned)) {

      /* we need to ensure that the value in %fp0 is not outside the valid

	 range for an unsigned int, otherwise there will be a floating

	 point exception in the library routine. */

      bool sw;

      exp e = getexp(ulongsh,nilexp,0,nilexp,nilexp,0,1333788672,val_tag);

      exp loc = sim_exp(shrealsh,FP1);

      lab = (have_continue())?next_lab(): overflow_jump;

      ins2(m_fmoves,shape_size(shrealsh),shape_size(shrealsh),zw(e),zw(loc));

      /*move(ulongsh,zw(e),zw(loc));  */

      sw = cmp(shrealsh,FP0,FP1,tst_gr);

      make_jump(branch_ins(tst_gr,sw,0,1),lab);

      kill_exp(e,e);

    }

#endif

    make_instr(m_call, p, null, ~save_msk);

    no_calls++;

#if 0

    if (have_continue() && !strcmp(nm,float_to_unsigned)) {

      make_label(lab);

    }

#endif

    have_cond = 0;

    return;

}

/*

    REGISTER MASKS

    regsinuse gives all the registers which are currented allocated

    values.  regsinproc is a cummulative record of all the registers

    which have been used in the current procedure.  reuseables is

    the record of all the current active reuseable registers.  bigregs

    records all registers in the current procedure which span procedure

    calls.

*/

bitpattern regsinuse;

bitpattern regsinproc;

bitpattern reuseables;

bitpattern regsindec;

bitpattern bigregs;

/*

    OTHER VARIABLES

    crt_ret_lab is a label number assigned to the return sequence of

    the current procedure.  just_ret is set to be true if the return

    sequence just consists of a single rts instruction.  no_calls

    records the number of procedure calls in the current procedure.

*/

long crt_ret_lab = 0;

bool just_ret = 0;

int no_calls = 0;

/*

    PROLOGUE POSITIONS

    This records the position of the prologue of the current procedure.

*/

mach_ins *prologue_ins;

/*

    GENERAL PURPOSE PROCEDURE PROLOGUE

    There are two cases.  If output_immediately is false then the

    prologue is not inserted until the end of the procedure.  Otherwise

    a number of special labels are used to represent values which will

    not be known until the end of the procedure.

*/

void prologue

(void)

{

    mach_op *op1, *op2;

    have_cond = 0;

    just_ret = 1;

    if (!output_immediately) {

	/* Just record position in this case */

	prologue_ins = current_ins;

	return;

    }

    /* Output generalized link and push instructions */

    op1 = make_register(REG_AP);

    op2 = make_special("PA");

    make_instr(m_linkl, op1, op2, 0);

    op1 = make_special("PB");

    op2 = make_indirect(REG_SP, 0);

    make_instr(m_moveml, op1, op2, 0);

    op1 = make_special("PC");

    op2 = make_indirect(REG_AP, 0);

    op2->of->plus = make_special("PD");

    make_instr(m_fmovemx, op1, op2, 0);

    return;

}

/*

    GENERAL PURPOSE PROCEDURE EPILOGUE

    The registers used in the procedure and the space used on the stack

    are analysed and used to form the procedure epilogue.  If

    output_immediately is false then we go back and fill in the

    prologue.  Otherwise the values of the special labels used in the

    prologue are output.  There is some testing to see if D1, A0, A1

    and FP1 can be put to better use.

*/

void epilogue

(int restore_only)

{

    int r;

    bitpattern m;

    long st, st1;

    mach_op *op1, *op2;

    int push_all = 0, use_link = 0;

    int tmp_d1 = -1, tmp_a0 = -1, tmp_a1 = -1;

    bitpattern rmsk = regs(regsinproc & save_msk);

    bitpattern smsk = rmsk;

    bitpattern cmsk = 0;

    bitpattern fmsk = 0;

    bitpattern fsmsk = fregs(regsinproc & save_msk);

    reset_round_mode();  /* restore the default floating point rounding mode */

    for (r = REG_FP7, m = 1; r >= REG_FP2; r--, m <<= 1) {

	if (regsinproc & regmsk(r))fmsk |= m;

    }

    if (no_calls) {

	smsk &= ~bigregs;

	fsmsk &= ~bigregs;

    }

    if (!restore_only) {

      make_label(crt_ret_lab);

    }

#if have_diagnostics

    if (diagnose)xdb_diag_proc_return();

#endif

    if (!output_immediately) {

	bool d1_free = 0;

	/* Use D1 if not already used */

	if (!(regsinproc & regmsk(REG_D1))) {

	    m = smsk & dreg_msk;

	    if (m) {

		/* Replace a used D-register by D1 */

		r = reg(m);

		reg_names[r] = reg_names[REG_D1];

		rmsk &= ~regmsk(r);

		smsk &= ~regmsk(r);

		cmsk |= regmsk(r);

	    } else {

		d1_free = 1;

	    }

	}

	/* Use A0 if not already used */

	if (!(regsinproc & regmsk(REG_A0))) {

	    m = smsk & areg_msk;

	    if (m) {

		/* Replace a used A-register by A0 */

		r = reg(m);

		reg_names[r] = reg_names[REG_A0];

		rmsk &= ~regmsk(r);

		smsk &= ~regmsk(r);

		cmsk |= regmsk(r);

	    } else if (no_calls == 0) {

		m = rmsk & dreg_msk;

		if (m) {

		    /* Move a used D-register into A0 */

		    tmp_a0 = reg(m);

		    rmsk &= ~regmsk(tmp_a0);

		    smsk = rmsk;

		    op1 = make_register(REG_A0);

		    op2 = make_register(tmp_a0);

		    make_instr(m_movl, op1, op2, regmsk(tmp_a0));

		    just_ret = 0;

		}

	    }

	}

	/* Use A1 if not already used */

	if (!(regsinproc & regmsk(REG_A1))) {

	    m = smsk & areg_msk;

	    if (m) {

		/* Replace a used A-register by A1 */

		r = reg(m);

		reg_names[r] = reg_names[REG_A1];

		rmsk &= ~regmsk(r);

		smsk &= ~regmsk(r);

		cmsk |= regmsk(r);

	    } else if (no_calls == 0) {

		m = rmsk & dreg_msk;

		if (m) {

		    /* Move a used D-register into A1 */

		    tmp_a1 = reg(m);

		    rmsk &= ~regmsk(tmp_a1);

		    smsk = rmsk;

		    op1 = make_register(REG_A1);

		    op2 = make_register(tmp_a1);

		    make_instr(m_movl, op1, op2, regmsk(tmp_a1));

		    just_ret = 0;

		}

	    }

	}

	/* Use FP1 if not already used */

	if (!(regsinproc & regmsk(REG_FP1))) {

	    for (r = REG_FP7, m = 1; r >= REG_FP2; r--, m <<= 1) {

		if (fsmsk & regmsk(r)) {

		    reg_names[r] = reg_names[REG_FP1];

		    fmsk &= ~m;

		    fsmsk &= ~regmsk(r);

		    cmsk |= regmsk(r);

		    r = REG_FP1;

		}

	    }

	}

	if (d1_free && no_calls == 0) {

	    m = rmsk & areg_msk;

	    if (m) {

		/* Move a used A-register into D1 */

		tmp_d1 = reg(m);

		rmsk &= ~regmsk(tmp_d1);

		op1 = make_register(REG_D1);

		op2 = make_register(tmp_d1);

		make_instr(m_movl, op1, op2, regmsk(tmp_d1));

		just_ret = 0;

	    }

	}

    }

    /* Calculate stack displacements */

/* todo use symbol instead of number */

    st1 = round(max_stack, 32) / 8 + 16 * bits_in(fmsk);

    st = st1 + 4 * bits_in(rmsk);

    if (st1 || used_stack || !push_all || output_immediately)use_link = 1;

    /* Remove floating-point registers from the stack */

    if (fmsk) {

	just_ret = 0;

	op1 = make_indirect(REG_AP, -st1);

	op2 = make_hex_value(fmsk);

	make_instr(m_fmovemx, op1, op2, 0);

    }

    /* Remove registers from the stack */

    if (rmsk) {

	just_ret = 0;

	if (push_all) {

	    for (r = REG_AP - 1; r > REG_D1; r--) {

		if (rmsk & regmsk(r)) {

		    op1 = make_inc_sp();

		    op2 = make_register(r);

		    make_instr(m_movl, op1, op2, regmsk(r));

		}

	    }

	} else {

	    if (must_use_bp) {

		op1 = make_indirect(REG_AP, -st);

	    } else {

		op1 = make_indirect(REG_SP, 0);

	    }

	    op2 = make_hex_value(rmsk);

	    make_instr(m_moveml, op1, op2, rmsk);

	    just_ret = 0;

	}

    }

    /* Output unlink instruction */

    if (use_link) {

	just_ret = 0;

	op1 = make_register(REG_AP);

	make_instr(m_unlk, op1, null, 0);

    }

    if (!restore_only) {

      /* Output return instruction */

      make_instr(m_rts, null, null, 0);

    }

    if (output_immediately) {

	/* Output stack displacement value */

	if (used_ldisp) {

	    op1 = make_int_data(use_link ? st + 4 : st);

	    set_special("S", op1);

	}

	/* Output values used in prologue */

	just_ret = 0;

	op1 = make_int_data(-st);

	set_special("PA", op1);

	op1 = make_hex_data(rmsk);

	set_special("PB", op1);

	op1 = make_hex_data(fmsk);

	set_special("PC", op1);

	op1 = make_int_data(-st1);

	set_special("PD", op1);

    } else if (!restore_only) {

	/* Go back to the prologue position */

	mach_ins *p = current_ins;

	current_ins = prologue_ins;

        cur_proc_env_size = ldisp = (use_link ? st + 4 : st);

	/* Output link instruction */

	if (use_link) {

	    long c = (push_all ? -st1 : -st);

	    int i = (c < -0x7fff ? m_linkl : m_linkw);

	    op1 = make_register(REG_AP);

	    op2 = make_value(c);

	    make_instr(i, op1, op2, 0);

	}

	/* Save register in D1 if necessary */

	if (tmp_d1 >= 0) {

	    op1 = make_register(tmp_d1);

	    op2 = make_register(REG_D1);

	    make_instr(m_movl, op1, op2, regmsk(REG_D1));

	}

	/* Save register in A0 if necessary */

	if (tmp_a0 >= 0) {

	    op1 = make_register(tmp_a0);

	    op2 = make_register(REG_A0);

	    make_instr(m_movl, op1, op2, regmsk(REG_A0));

	}

	/* Save register in A1 if necessary */

	if (tmp_a1 >= 0) {

	    op1 = make_register(tmp_a1);

	    op2 = make_register(REG_A1);

	    make_instr(m_movl, op1, op2, regmsk(REG_A1));

	}

	/* Put registers onto the stack */

	if (rmsk) {

	    if (push_all) {

		for (r = REG_D1 + 1; r < REG_AP; r++) {

		    if (rmsk & regmsk(r)) {

			op1 = make_register(r);

			op2 = make_dec_sp();

			make_instr(m_movl, op1, op2, 0);

		    }

		}

	    } else {

		op1 = make_hex_value(rmsk);

		op2 = make_indirect(REG_SP, 0);

		make_instr(m_moveml, op1, op2, 0);

	    }

	}

	/* Put floating-point registers onto the stack */

	if (fmsk) {

	    op1 = make_hex_value(fmsk);

	    op2 = make_indirect(REG_AP, -st1);

	    make_instr(m_fmovemx, op1, op2, 0);

	}

	/* Return to previous position */

	current_ins = p;

    }

    callmsk = cmsk;

    have_cond = 0;

    return;

}

/*

    PROFILING

    In order for prof and gprof to work, we need to associate four bytes

    of data with each procedure and make the first two lines of the

    procedure move the address of these bytes into the A0 register and

    call mcount.  Unfortunately mcount uses A1 so, if the procedure returns

    a complex result, the address where we are meant to put it, which was

    in A1, is lost.  cc doesn't take account of this, and so can go

    wrong under these circumstances.  I instead call a dummy routine,

    Lmcount, given below, which stores the value of A1 and then jumps to

    mcount, and restore the value of A1 afterwards.

			text

		Lmcount:

			mov.l	%a1, Lmstore

			jmp.l	mcount

			data

		Lmstore:

			long	0

    The flag used_my_mcount is set to be true if Lmcount is used.

*/

static bool used_my_mcount = 0;

/*

    OUTPUT PROFILING DATA

    This routine outputs the profiling data for a procedure.  If save_a1

    is true, the alternative profiling routine is used.

*/

void out_profile

(bool save_a1)

{

    exp z;

    mach_op *op1, *op2;

    /* Make a new label */

    long lb = next_lab();

    if (profiling_uses_lea) {

	op1 = make_lab_data(lb, 0);