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/* * crt0.S -- startup file for m68k-coff * */ .title "crt0.S for m68k-coff" /* These are predefined by new versions of GNU cpp. */ #ifndef __USER_LABEL_PREFIX__ #define __USER_LABEL_PREFIX__ _ #endif #ifndef __REGISTER_PREFIX__ #define __REGISTER_PREFIX__ #endif /* ANSI concatenation macros. */ #define CONCAT1(a, b) CONCAT2(a, b) #define CONCAT2(a, b) a ## b /* Use the right prefix for global labels. */ #define SYM(x) CONCAT1 (__USER_LABEL_PREFIX__, x) /* Use the right prefix for registers. */ #define REG(x) CONCAT1 (__REGISTER_PREFIX__, x) #define d0 REG (d0) #define d1 REG (d1) #define d2 REG (d2) #define d3 REG (d3) #define d4 REG (d4) #define d5 REG (d5) #define d6 REG (d6) #define d7 REG (d7) #define a0 REG (a0) #define a1 REG (a1) #define a2 REG (a2) #define a3 REG (a3) #define a4 REG (a4) #define a5 REG (a5) #define a6 REG (a6) #define fp REG (fp) #define sp REG (sp) /* * Set up some room for a stack. We just grab a chunk of memory. */ .set stack_size, 0x2000 .comm SYM (stack), stack_size /* * Define an empty environment. */ .data .align 2 SYM (environ): .long 0 .align 2 .text .global SYM (stack) .global SYM (main) .global SYM (exit) /* * This really should be __bss_start, not SYM (__bss_start). */ .global __bss_start /* * start -- set things up so the application will run. */ SYM (start): link a6, #-8 moveal #SYM (stack) + stack_size, sp /* * zerobss -- zero out the bss section */ moveal #__bss_start, a0 moveal #SYM (end), a1 1: movel #0, (a0) leal 4(a0), a0 cmpal a0, a1 bne 1b /* * Call the main routine from the application to get it going. * main (argc, argv, environ) * We pass argv as a pointer to NULL. */ pea 0 pea SYM (environ) pea sp@(4) pea 0 jsr SYM (main) movel d0, sp@- /* * _exit -- Exit from the application. Normally we cause a user trap * to return to the ROM monitor for another run. */ SYM (exit): trap #0
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