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#include "dietfeatures.h"
#include "mips-asm.h"
.file "start.S"
#define zero 0
#define ra 31
#define sp 29
#define a0 4
#define a1 5
#define a2 6
#define gp 28
.text
.global __start
.type __start,@function
__start:
#ifdef __pic__
/* initialize gp pointer */
.set noreorder
bltzal $0,0f
nop
0: .cpload $31
.set reorder
#else
/* _gp is provided by the linker and points into the middle of the
* "small data" section (.sdata and .sbss) allocated by the
* -G 8 compiler option */
PTR_LA $gp, _gp
#endif
move $ra, $zero /* prime stack frame */
lw $a0, 0($sp) /* load argc */
#if _MIPS_SIM == _ABI64
/* The same lack of clarity w.r.t. the MIPS calling conventions
* apply here as with MIPS32. (See below.) */
daddu $a1, $sp, 8 /* load argv */
li $t0, -8
and $sp, $sp, $t0
dsubu $sp, 48 /* make room for 4 arguments, RA + pad */
sd $ra, 40($sp) /* close stack frame */
#else
addu $a1, $sp, 4 /* load argv. huh? should be 4, right? */
and $sp, 0xfffffff8 /* align stack to 8 bytes */
subu $sp, 24 /* make room for 4 arguments, RA + pad */
/* I don't understand the MIPS calling convention. Why do you
need to make room on the stack for arguments you pass in
registers? Anyway, if we don't do this, the arguments are
garbled. */
sw $ra, 20($sp) /* close stack frame */
#endif
addu $a2, $a0, 1 /* load envp */
#if _MIPS_SIM == _ABI64
dsll $a2, $a2, 3
#else
sll $a2, $a2, 2
#endif
#ifdef WANT_DYNAMIC
/* FIXME: dl_init parameter ??? */
PTR_LA $25, _dyn_start
#else
PTR_LA $25, CALL_IN_STARTCODE
#endif
PTR_ADD $a2, $a2, $a1
PTR_SW $a2, environ
jalr $25
PTR_LA $25, exit
move $4,$2
jalr $25
.global __main
.type __main,@function
__main:
j $31
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