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diff --git a/src/crt0.c b/src/crt0.c
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+/* C code startup routine.
+ Copyright (C) 1985, 1986 Free Software Foundation, Inc.
+
+ 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 1, 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+In other words, you are welcome to use, share and improve this program.
+You are forbidden to forbid anyone else to use, share and improve
+what you give them. Help stamp out software-hoarding! */
+
+
+/* The standard Vax 4.2 Unix crt0.c cannot be used for Emacs
+ because it makes `envron' an initialized variable.
+ It is easiest to have a special crt0.c on all machines
+ though I don't know whether other machines actually need it. */
+
+/* On the vax and 68000, in BSD4.2 and USG5.2,
+ this is the data format on startup:
+ (vax) ap and fp are unpredictable as far as I know; don't use them.
+ sp -> word containing argc
+ word pointing to first arg string
+ [word pointing to next arg string]... 0 or more times
+ 0
+Optionally:
+ [word pointing to environment variable]... 1 or more times
+ ...
+ 0
+And always:
+ first arg string
+ [next arg string]... 0 or more times
+*/
+
+/* On the 16000, at least in the one 4.2 system I know about,
+ the initial data format is
+ sp -> word containing argc
+ word containing argp
+ word pointing to first arg string, and so on as above
+*/
+
+#include "config.h"
+
+/* ******** WARNING ********
+ Do not insert any data definitions before data_start!
+ Since this is the first file linked, the address of the following
+ variable should correspond to the start of initialized data space.
+ On some systems this is a constant that is independent of the text
+ size for shared executables. On others, it is a function of the
+ text size. In short, this seems to be the most portable way to
+ discover the start of initialized data space dynamically at runtime,
+ for either shared or unshared executables, on either swapping or
+ virtual systems. It only requires that the linker allocate objects
+ in the order encountered, a reasonable model for most Unix systems.
+ Similarly, note that the address of _start() should be the start
+ of text space. Fred Fish, UniSoft Systems Inc. */
+
+int data_start = 0;
+
+#ifdef NEED_ERRNO
+int errno;
+#endif
+
+#ifndef DONT_NEED_ENVIRON
+char **environ;
+#endif
+
+#if defined(orion) || defined(pyramid) || defined(celerity) || defined(ALLIANT) || defined(clipper)
+
+#ifdef ALLIANT
+/* _start must initialize _curbrk and _minbrk on the first startup;
+ when starting up after dumping, it must initialize them to what they were
+ before the dumping, since they are in the shared library and
+ are not dumped. See ADJUST_EXEC_HEADER in m-alliant.h. */
+extern unsigned char *_curbrk, *_minbrk;
+extern unsigned char end;
+unsigned char *_setbrk = &end;
+#ifdef ALLIANT_2800
+unsigned char *_end = &end;
+#endif
+#endif
+
+#ifndef DUMMIES
+#define DUMMIES
+#endif
+
+_start (DUMMIES argc, argv, envp)
+ int argc;
+ char **argv, **envp;
+{
+#ifdef ALLIANT
+#ifdef ALLIANT_2800
+ _curbrk = _end;
+ _minbrk = _end;
+#else
+ _curbrk = _setbrk;
+ _minbrk = _setbrk;
+#endif
+#endif
+
+ environ = envp;
+
+ exit (main (argc, argv, envp));
+}
+
+#endif /* orion or pyramid or celerity or alliant or clipper */
+
+#if defined (ns16000) && !defined (sequent) && !defined (UMAX)
+
+_start ()
+{
+/* On 16000, _start pushes fp onto stack */
+ start1 ();
+}
+
+/* ignore takes care of skipping the fp value pushed in start. */
+static
+start1 (ignore, argc, argv)
+ int ignore;
+ int argc;
+ register char **argv;
+{
+ environ = argv + argc + 1;
+
+ if (environ == *argv)
+ environ--;
+ exit (main (argc, argv, environ));
+}
+#endif /* ns16000, not sequent and not UMAX */
+
+#ifdef UMAX
+_start()
+{
+ asm(" exit [] # undo enter");
+ asm(" .set exitsc,1");
+ asm(" .set sigcatchall,0x400");
+
+ asm(" .globl _exit");
+ asm(" .globl start");
+ asm(" .globl __start");
+ asm(" .globl _main");
+ asm(" .globl _environ");
+ asm(" .globl _sigvec");
+ asm(" .globl sigentry");
+
+ asm("start:");
+ asm(" br .xstart");
+ asm(" .org 0x20");
+ asm(" .double p_glbl,0,0xf00000,0");
+ asm(" .org 0x30");
+ asm(".xstart:");
+ asm(" adjspb $8");
+ asm(" movd 8(sp),0(sp) # argc");
+ asm(" addr 12(sp),r0");
+ asm(" movd r0,4(sp) # argv");
+ asm("L1:");
+ asm(" movd r0,r1");
+ asm(" addqd $4,r0");
+ asm(" cmpqd $0,0(r1) # null args term ?");
+ asm(" bne L1");
+ asm(" cmpd r0,0(4(sp)) # end of 'env' or 'argv' ?");
+ asm(" blt L2");
+ asm(" addqd $-4,r0 # envp's are in list");
+ asm("L2:");
+ asm(" movd r0,8(sp) # env");
+ asm(" movd r0,@_environ # indir is 0 if no env ; not 0 if env");
+ asm(" movqd $0,tos # setup intermediate signal handler");
+ asm(" addr @sv,tos");
+ asm(" movzwd $sigcatchall,tos");
+ asm(" jsr @_sigvec");
+ asm(" adjspb $-12");
+ asm(" jsr @_main");
+ asm(" adjspb $-12");
+ asm(" movd r0,tos");
+ asm(" jsr @_exit");
+ asm(" adjspb $-4");
+ asm(" addr @exitsc,r0");
+ asm(" svc");
+ asm(" .align 4 # sigvec arg");
+ asm("sv:");
+ asm(" .double sigentry");
+ asm(" .double 0");
+ asm(" .double 0");
+
+ asm(" .comm p_glbl,1");
+}
+#endif /* UMAX */
+
+#ifdef CRT0_DUMMIES
+
+/* Define symbol "start": here; some systems want that symbol. */
+#ifdef DOT_GLOBAL_START
+asm(" .text ");
+asm(" .globl start ");
+asm(" start: ");
+#endif /* DOT_GLOBAL_START */
+
+#ifdef NODOT_GLOBAL_START
+asm(" text ");
+asm(" global start ");
+asm(" start: ");
+#endif /* NODOT_GLOBAL_START */
+
+static start1 ();
+
+_start ()
+{
+/* On vax, nothing is pushed here */
+/* On sequent, bogus fp is pushed here */
+ start1 ();
+}
+
+static
+start1 (CRT0_DUMMIES argc, xargv)
+ int argc;
+ char *xargv;
+{
+ register char **argv = &xargv;
+ environ = argv + argc + 1;
+
+ if ((char *)environ == xargv)
+ environ--;
+ exit (main (argc, argv, environ));
+}
+#else /* not CRT0_DUMMIES */
+
+/* "m68k" and "m68000" both stand for m68000 processors,
+ but with different program-entry conventions.
+ This is a kludge. Now that the CRT0_DUMMIES mechanism above exists,
+ most of these machines could use the vax code above
+ with some suitable definition of CRT0_DUMMIES.
+ Then the symbol m68k could be flushed.
+ But I don't want to risk breaking these machines
+ in a version 17 patch release, so that change is being put off. */
+
+#ifdef m68k /* Can't do it all from C */
+ asm (" global _start");
+ asm (" text");
+ asm ("_start:");
+#ifndef NU
+#ifdef STRIDE
+ asm (" comm havefpu%,2");
+#else /* m68k, not STRIDE */
+ asm (" comm splimit%,4");
+#endif /* STRIDE */
+ asm (" global exit");
+ asm (" text");
+#ifdef STRIDE
+ asm (" trap &3");
+ asm (" mov.w %d0,havefpu%");
+#else /* m68k, not STRIDE */
+ asm (" mov.l %d0,splimit%");
+#endif /* STRIDE */
+#endif /* not NU */
+ asm (" jsr start1");
+ asm (" mov.l %d0,(%sp)");
+ asm (" jsr exit");
+ asm (" mov.l &1,%d0"); /* d0 = 1 => exit */
+ asm (" trap &0");
+#else /* m68000, not m68k */
+
+#ifdef m68000
+
+#ifdef ISI68K
+/* Added by ESM Sun May 24 12:44:02 1987 to get new ISI library to work */
+#ifdef BSD4_3
+static foo () {
+#endif
+ asm (" .globl is68020");
+ asm ("is68020:");
+#ifndef BSD4_3
+ asm (" .long 0x00000000");
+ asm (" .long 0xffffffff");
+/* End of stuff added by ESM */
+#endif
+ asm (" .text");
+ asm (" .globl __start");
+ asm ("__start:");
+ asm (" .word 0");
+ asm (" link fp,#0");
+ asm (" jbsr _start1");
+ asm (" unlk fp");
+ asm (" rts");
+#ifdef BSD4_3
+ }
+#endif
+#else /* not ISI68K */
+
+_start ()
+{
+/* On 68000, _start pushes a6 onto stack */
+ start1 ();
+}
+#endif /* not ISI68k */
+#endif /* m68000 */
+#endif /* m68k */
+
+#if defined(m68k) || defined(m68000)
+/* ignore takes care of skipping the a6 value pushed in start. */
+static
+#if defined(m68k)
+start1 (argc, xargv)
+#else
+start1 (ignore, argc, xargv)
+#endif
+ int argc;
+ char *xargv;
+{
+ register char **argv = &xargv;
+ environ = argv + argc + 1;
+
+ if ((char *)environ == xargv)
+ environ--;
+ exit (main (argc, argv, environ));
+}
+
+#endif /* m68k or m68000 */
+
+#endif /* not CRT0_DUMMIES */
+
+#ifdef hp9000s300
+int argc_value;
+char **argv_value;
+#ifdef OLD_HP_ASSEMBLER
+ asm(" text");
+ asm(" globl __start");
+ asm(" globl _exit");
+ asm(" globl _main");
+ asm("__start");
+ asm(" dc.l 0");
+ asm(" subq.w #0x1,d0");
+ asm(" move.w d0,float_soft");
+ asm(" move.l 0x4(a7),d0");
+ asm(" beq.s skip_1");
+ asm(" move.l d0,a0");
+ asm(" clr.l -0x4(a0)");
+ asm("skip_1");
+ asm(" move.l a7,a0");
+ asm(" subq.l #0x8,a7");
+ asm(" move.l (a0),(a7)");
+ asm(" move.l (a0),_argc_value");
+ asm(" addq.l #0x4,a0");
+ asm(" move.l a0,0x4(a7)");
+ asm(" move.l a0,_argv_value");
+ asm("incr_loop");
+ asm(" tst.l (a0)+");
+ asm(" bne.s incr_loop");
+ asm(" move.l 0x4(a7),a1");
+ asm(" cmp.l (a1),a0");
+ asm(" blt.s skip_2");
+ asm(" subq.l #0x4,a0");
+ asm("skip_2");
+ asm(" move.l a0,0x8(a7)");
+ asm(" move.l a0,_environ");
+ asm(" jsr _main");
+ asm(" addq.l #0x8,a7");
+ asm(" move.l d0,-(a7)");
+ asm(" jsr _exit");
+ asm(" move.w #0x1,d0");
+ asm(" trap #0x0");
+ asm(" comm float_soft,4");
+/* float_soft is allocated in this way because C would
+ put an underscore character in its name otherwise. */
+
+#else /* new hp assembler */
+
+ asm(" text");
+ asm(" global float_loc");
+ asm(" set float_loc,0xFFFFB000");
+ asm(" global fpa_loc");
+ asm(" set fpa_loc,0xfff08000");
+ asm(" global __start");
+ asm(" global _exit");
+ asm(" global _main");
+ asm("__start:");
+ asm(" byte 0,0,0,0");
+ asm(" subq.w &1,%d0");
+ asm(" mov.w %d0,float_soft");
+ asm(" mov.w %d1,flag_68881");
+#ifndef HPUX_68010
+ asm(" beq.b skip_float");
+ asm(" fmov.l &0x7400,%fpcr");
+/* asm(" fmov.l &0x7480,%fpcr"); */
+#endif /* HPUX_68010 */
+ asm("skip_float:");
+ asm(" mov.l %a0,%d0");
+ asm(" add.l %d0,%d0");
+ asm(" subx.w %d1,%d1");
+ asm(" mov.w %d1,flag_68010");
+ asm(" add.l %d0,%d0");
+ asm(" subx.w %d1,%d1");
+ asm(" mov.w %d1,flag_fpa");
+ asm(" tst.l %d2");
+ asm(" ble.b skip_3");
+ asm(" lsl flag_68881");
+ asm(" lsl flag_fpa");
+ asm("skip_3:");
+ asm(" mov.l 4(%a7),%d0");
+ asm(" beq.b skip_1");
+ asm(" mov.l %d0,%a0");
+ asm(" clr.l -4(%a0)");
+ asm("skip_1:");
+ asm(" mov.l %a7,%a0");
+ asm(" subq.l &8,%a7");
+ asm(" mov.l (%a0),(%a7)");
+ asm(" mov.l (%a0),_argc_value");
+ asm(" addq.l &4,%a0");
+ asm(" mov.l %a0,4(%a7)");
+ asm(" mov.l %a0,_argv_value");
+ asm("incr_loop:");
+ asm(" tst.l (%a0)+");
+ asm(" bne.b incr_loop");
+ asm(" mov.l 4(%a7),%a1");
+ asm(" cmp.l %a0,(%a1)");
+ asm(" blt.b skip_2");
+ asm(" subq.l &4,%a0");
+ asm("skip_2:");
+ asm(" mov.l %a0,8(%a7)");
+ asm(" mov.l %a0,_environ");
+ asm(" jsr _main");
+ asm(" addq.l &8,%a7");
+ asm(" mov.l %d0,-(%a7)");
+ asm(" jsr _exit");
+ asm(" mov.w &1,%d0");
+ asm(" trap &0");
+ asm(" comm float_soft, 4");
+ asm(" comm flag_68881, 4");
+ asm(" comm flag_68010, 4");
+ asm(" comm flag_fpa, 4");
+
+#endif /* new hp assembler */
+#endif /* hp9000s300 */
+
+#ifdef GOULD
+
+/* startup code has to be in near text rather
+ than fartext as allocated by the C compiler. */
+ asm(" .text");
+ asm(" .align 2");
+ asm(" .globl __start");
+ asm(" .text");
+ asm("__start:");
+/* setup base register b1 (function base). */
+ asm(" .using b1,.");
+ asm(" tpcbr b1");
+/* setup base registers b3 through b7 (data references). */
+ asm(" file basevals,b3");
+/* setup base register b2 (stack pointer); it should be
+ aligned on a 8-word boundary; but because it is pointing
+ to argc, its value should be remembered (in r5). */
+ asm(" movw b2,r4");
+ asm(" movw b2,r5");
+ asm(" andw #~0x1f,r4");
+ asm(" movw r4,b2");
+/* allocate stack frame to do some work. */
+ asm(" subea 16w,b2");
+/* initialize signal catching for UTX/32 1.2; this is
+ necessary to make restart from saved image work. */
+ asm(" movea sigcatch,r1");
+ asm(" movw r1,8w[b2]");
+ asm(" svc #1,#150");
+/* setup address of argc for start1. */
+ asm(" movw r5,8w[b2]");
+ asm(" func #1,_start1");
+ asm(" halt");
+/* space for ld to store base register initial values. */
+ asm(" .align 5");
+ asm("basevals:");
+ asm(" .word __base3,__base4,__base5,__base6,__base7");
+
+static
+start1 (xargc)
+ int *xargc;
+{
+ register int argc;
+ register char **argv;
+
+ argc = *xargc;
+ argv = (char **)(xargc) + 1;
+ environ = argv + argc + 1;
+
+ if (environ == argv)
+ environ--;
+ exit (main (argc, argv, environ));
+
+}
+
+#endif /* GOULD */
+
+#ifdef elxsi
+extern int errno;
+extern char **environ;
+
+_start()
+{
+ register int r;
+
+ errno = 0;
+ environ = *(&environ + 8);
+ _stdinit();
+ r = main(*(&environ + 6), *(&environ + 7), environ);
+ exit(r);
+ _exit(r);
+}
+#endif /* elxsi */
+
+
+#ifdef sparc
+asm (".global __start");
+asm (".text");
+asm ("__start:");
+asm (" mov 0, %fp");
+asm (" ld [%sp + 64], %o0");
+asm (" add %sp, 68, %o1");
+asm (" sll %o0, 2, %o2");
+asm (" add %o2, 4, %o2");
+asm (" add %o1, %o2, %o2");
+asm (" sethi %hi(_environ), %o3");
+asm (" st %o2, [%o3+%lo(_environ)]");
+asm (" andn %sp, 7, %sp");
+asm (" call _main");
+asm (" sub %sp, 24, %sp");
+asm (" call __exit");
+asm (" nop");
+
+#endif /* sparc */
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