diff options
Diffstat (limited to 'sysdeps/unix/sysv/linux/alpha/start.S')
-rw-r--r-- | sysdeps/unix/sysv/linux/alpha/start.S | 95 |
1 files changed, 45 insertions, 50 deletions
diff --git a/sysdeps/unix/sysv/linux/alpha/start.S b/sysdeps/unix/sysv/linux/alpha/start.S index a7099f6..bffa913 100644 --- a/sysdeps/unix/sysv/linux/alpha/start.S +++ b/sysdeps/unix/sysv/linux/alpha/start.S @@ -1,5 +1,5 @@ /* Copyright (C) 1993, 1995, 1996 Free Software Foundation, Inc. - Contributed by Brendan Kehoe (brendan@zen.org). + Contributed by Richard Henderson <rth@tamu.edu> The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Library General Public License as @@ -18,81 +18,76 @@ Cambridge, MA 02139, USA. */ #include <sysdep.h> - .comm errno, 4 -#ifdef __ELF__ - .type errno, @object -#endif - .text -LEAF(__start, 16) - lda sp, -16(sp) - .prologue 0 - - stq zero, 8(sp) /* terminate frame chain */ - - br t0, 1f -1: ldgp gp, 0(t0) - - mov zero, a0 /* establish __fpu_control w/kernel */ - jsr ra, __setfpucw + .globl __start + .align 3 + .ent __start, 0 +__start: + .frame fp, 0, zero + mov zero, fp + br gp, 1f +1: ldgp gp, 0(gp) + .prologue 1 + + /* Save v0. When starting a binary via the dynamic linker, s0 + contains the address of the shared library termination function, + which we will register below with atexit() to be called by exit(). + If we are statically linked, this will be NULL. */ + mov v0, s0 + + /* Do essential libc initialization (sp points to argc, argv, and envp) */ + jsr ra, __libc_init_first ldgp gp, 0(ra) - /* clear out errno. */ - stl zero, (errno) + /* Now that we have the proper stack frame, register library termination + function, if there is any: */ - ldl a0, 16(sp) /* get argc */ - lda a1, 24(sp) /* get argv */ + beq s0, 1f + mov s0, a0 + jsr ra, atexit + ldgp gp, 0(ra) +1: - /* initialize environ: */ - lda t0, environ - s8addq a0, a1, a2 - addq a2, 0x8, a2 - stq a2, 0(t0) + /* Extract the arguments and environment as encoded on the stack. */ + ldl a0, 0(sp) /* get argc */ + lda a1, 8(sp) /* get argv */ + s8addq a0, a1, a2 /* get envp */ + addq a2, 8, a2 + stq a2, _environ - mov a0, s0 + mov a0, s0 /* tuck them away */ mov a1, s1 mov a2, s2 #ifdef HAVE_INITFINI - /* register the _fini sections to ensure destructors get run: */ - lda a0, _fini - jsr ra, atexit - ldgp gp, 0(ra) - - /* Now run the _init section of the program itself. The _init - sections of shared libraries will be run by the dynamic linker. */ + /* Call _init, the entry point to our own .init section. */ jsr ra, _init ldgp gp, 0(ra) - /* initialize constructors: */ - jsr ra, __main + /* Register our .fini section with atexit. */ + lda a0, _fini + jsr ra, atexit ldgp gp, 0(ra) #else - jsr ra, __libc_init + /* initialize constructors: */ + jsr ra, __main ldgp gp, 0(ra) #endif - mov s0, a0 mov s1, a1 mov s2, a2 + /* Call the user's main and exit with its return value. */ jsr ra, main ldgp gp, 0(ra) mov v0, a0 + jsr ra, exit - lda pv, exit - jsr ra, (pv), 1 - ldgp gp, 0(ra) - - /* in case exit returns: */ - -1: ldi v0, __NR_exit - call_pal PAL_callsys - br 1b - - .end __start - + /* Die very horribly if exit returns. Call_pal hlt is callable from + kernel mode only; this will result in an illegal instruction trap. */ + call_pal 0 +END(__start) /* Define a symbol for the first piece of initialized data. */ .data |