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Diffstat (limited to 'libgloss/mips/crt0.S')
| -rw-r--r-- | libgloss/mips/crt0.S | 232 |
1 files changed, 0 insertions, 232 deletions
diff --git a/libgloss/mips/crt0.S b/libgloss/mips/crt0.S deleted file mode 100644 index 8bd46ebf0..000000000 --- a/libgloss/mips/crt0.S +++ /dev/null @@ -1,232 +0,0 @@ -/* - * crt0.S -- startup file for MIPS. - * - * Copyright (c) 1995, 1996, 1997, 2001 Cygnus Support - * - * The authors hereby grant permission to use, copy, modify, distribute, - * and license this software and its documentation for any purpose, provided - * that existing copyright notices are retained in all copies and that this - * notice is included verbatim in any distributions. No written agreement, - * license, or royalty fee is required for any of the authorized uses. - * Modifications to this software may be copyrighted by their authors - * and need not follow the licensing terms described here, provided that - * the new terms are clearly indicated on the first page of each file where - * they apply. - */ - -#ifdef __mips16 -/* This file contains 32 bit assembly code. */ - .set nomips16 -#endif - -#include "regs.S" - -/* - * Set up some room for a stack. We just grab a chunk of memory. - */ -#define STACK_SIZE 0x4000 -#define GLOBAL_SIZE 0x2000 - -#define STARTUP_STACK_SIZE 0x0100 - -/* This is for referencing addresses that are not in the .sdata or - .sbss section under embedded-pic, or before we've set up gp. */ -#ifdef __mips_embedded_pic -# ifdef __mips64 -# define LA(t,x) la t,x-PICBASE ; daddu t,s0,t -# else -# define LA(t,x) la t,x-PICBASE ; addu t,s0,t -# endif -#else /* __mips_embedded_pic */ -# define LA(t,x) la t,x -#endif /* __mips_embedded_pic */ - - .comm __memsize, 12 - .comm __lstack, STARTUP_STACK_SIZE - .comm __stackbase,4 - - .text - .align 2 - -/* Without the following nop, GDB thinks _start is a data variable. - * This is probably a bug in GDB in handling a symbol that is at the - * start of the .text section. - */ - nop - - .globl _start - .ent _start -_start: - .set noreorder -#ifdef __mips_embedded_pic - PICBASE = .+8 - bal PICBASE - nop - move s0,$31 -#endif -#if (__mips < 3) || (__mips_fpr==32) -#define STATUS_MASK (SR_CU1|SR_PE) -#else -# For mips3 or mips4, turn on 64-bit addressing and additional float regs -#define STATUS_MASK (SR_CU1|SR_PE|SR_FR|SR_KX|SR_SX|SR_UX) -#endif - li v0, STATUS_MASK - mtc0 v0, C0_SR - mtc0 zero, C0_CAUSE - nop - -/* Check for FPU presence. Don't check if we know that soft_float is - being used. (This also avoids illegal instruction exceptions.) */ - -#ifndef __mips_soft_float - li t2,0xAAAA5555 - mtc1 t2,fp0 /* write to FPR 0 */ - mtc1 zero,fp1 /* write to FPR 1 */ - mfc1 t0,fp0 - mfc1 t1,fp1 - nop - bne t0,t2,1f /* check for match */ - nop - bne t1,zero,1f /* double check */ - nop - j 2f /* FPU is present. */ - nop -#endif -1: - /* FPU is not present. Set status register to say that. */ - li v0, (STATUS_MASK-(STATUS_MASK & SR_CU1)) - mtc0 v0, C0_SR - nop -2: - - -/* Fix high bits, if any, of the PC so that exception handling - doesn't get confused. */ - LA (v0, 3f) - jr v0 - nop -3: - LA (gp, _gp) # set the global data pointer - .end _start - -/* - * zero out the bss section. - */ - .globl __memsize - .globl get_mem_info .text - .globl __stack - .globl __global - .ent zerobss -zerobss: - LA (v0, _fbss) - LA (v1, _end) -3: - sw zero,0(v0) - bltu v0,v1,3b - addiu v0,v0,4 # executed in delay slot - - la t0, __lstack # make a small stack so we - addiu sp, t0, STARTUP_STACK_SIZE # can run some C code - la a0, __memsize # get the usable memory size - jal get_mem_info - nop - - /* setup the stack pointer */ - LA (t0, __stack) # is __stack set ? - bne t0,zero,4f - nop - - /* NOTE: a0[0] contains the amount of memory available, and - not the last memory address. */ - lw t0,0(a0) # last address of memory available - la t1,K0BASE # cached kernel memory - addu t0,t0,t1 # get the end of memory address - /* We must subtract 24 bytes for the 3 8 byte arguments to main, in - case main wants to write them back to the stack. The caller is - supposed to allocate stack space for parameters in registers in - the old MIPS ABIs. We must do this even though we aren't passing - arguments, because main might be declared to have them. - - Some ports need a larger alignment for the stack, so we subtract - 32, which satisifes the stack for the arguments and keeps the - stack pointer better aligned. */ - subu t0,t0,32 # and generate a starting stack-pointer -4: - move sp,t0 # set stack pointer - sw sp,__stackbase # keep this for future ref - .end zerobss - -/* - * initialize target specific stuff. Only execute these - * functions it they exist. - */ - .globl hardware_init_hook .text - .globl software_init_hook .text - .type _fini,@function - .type _init,@function - .globl atexit .text - .globl exit .text - .ent init -init: - LA (t9, hardware_init_hook) # init the hardware if needed - beq t9,zero,6f - nop - jal t9 - nop -6: - LA (t9, software_init_hook) # init the hardware if needed - beq t9,zero,7f - nop - jal t9 - nop -7: - LA (a0, _fini) - jal atexit - nop - -#ifdef GCRT0 - .globl _ftext - .globl _extext - LA (a0, _ftext) - LA (a1, _etext) - jal monstartup - nop -#endif - - jal _init # run global constructors - nop - - move a0,zero # set argc to 0 - jal main # call the program start function - nop - - # fall through to the "exit" routine - jal exit # call libc exit to run the G++ - # destructors - move a0,v0 # pass through the exit code - .end init - -/* - * _exit -- Exit from the application. Normally we cause a user trap - * to return to the ROM monitor for another run. NOTE: This is - * the only other routine we provide in the crt0.o object, since - * it may be tied to the "_start" routine. It also allows - * executables that contain a complete world to be linked with - * just the crt0.o object. - */ - .globl _exit - .ent _exit -_exit: -7: -#ifdef GCRT0 - jal _mcleanup - nop -#endif - # break instruction can cope with 0xfffff, but GAS limits the range: - break 1023 - nop - b 7b # but loop back just in-case - nop - .end _exit - -/* EOF crt0.S */ |