122 lines
2.3 KiB
ArmAsm
122 lines
2.3 KiB
ArmAsm
/*********/
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/* .data */
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/*********/
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.section .data.argv
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argv_str:
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.ascii "main\0"
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.align 4
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argv:
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.word argv_str
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.word 0
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/**********/
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/* _start */
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/**********/
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.section .start
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.globl _start
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.type _start,@function
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_start:
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.option push
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.option norelax
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la gp, __global_pointer$
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.option pop
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la sp, __stack_end
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/* Load data section */
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.type _startup_copy_data,@function
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_startup_copy_data:
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la a0, __data_load
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la a1, __data_start
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la a2, __data_end
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bgeu a1, a2, 2f
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1:
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lw t0, (a0)
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sw t0, (a1)
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addi a0, a0, 4
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addi a1, a1, 4
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bltu a1, a2, 1b
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2:
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.size _startup_copy_data, . - _startup_copy_data
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/* Clear bss section */
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.type _startup_clear_bss,@function
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_startup_clear_bss:
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la a0, __bss_start
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la a1, __bss_end
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bgeu a0, a1, 2f
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1:
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sw zero, (a0)
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addi a0, a0, 4
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bltu a0, a1, 1b
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2:
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.size _startup_clear_bss, . - _startup_clear_bss
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/* Call static constructors */
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.weak __libc_init_array
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la t0, __libc_init_array
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beq t0, zero, .skip_libc_init
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jalr t0
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.skip_libc_init:
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/* Call main, with argc, argv */
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la a0, 1
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la a1, argv
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call main
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/* Save main's return value */
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mv t0, a0
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/* static destructors */
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.weak __libc_fini_array
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la t0, __libc_fini_array
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beq t0, zero, .skip_libc_fini
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jalr t0
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.skip_libc_fini:
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/* Restore main's return value */
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mv a0, t0
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call __gnat_exit
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2: j 2b
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.globl __gnat_exit
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.type __gnat_exit,@function
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.globl _abort
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.type abort,@function
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abort:
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__gnat_exit:
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/* Write to the SiFive Test device on QEMU to shutdown */
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li t0, 0x5555
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li t1, 0x100000
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sw t0, (t1)
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j __gnat_exit
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/* Weak alias _exit to __gnat_exit */
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.weak _exit
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.set _exit,__gnat_exit
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.globl putchar
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.type putchar,@function
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putchar:
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li t1, 268513280
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li t1, 0x10013000
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li t2, 0x80000000
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.loop:
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lw t3, 0(t1)
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and t3, t3, t2
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bnez t3, .loop
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sb a0, 0(t1)
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ret
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