39 lines
936 B
ArmAsm
39 lines
936 B
ArmAsm
.text
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.global _start
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.type _start, @function
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_start:
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# Initialize global pointer
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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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# Clear the bss segment
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la a0,__bss_start # a0 = start zeroing memory here
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la a1,__BSS_END__ # a1 = end zeroing here-1
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clear_bss:
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bgeu a0,a1,done_bss # while (!(a0 >= a1))
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sb x0,0(a0) # *a0 = 0;
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addi a0,a0,1 # ++a0
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beq x0,x0,clear_bss
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done_bss:
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# abort execution here
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ebreak
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.size _start, .-_start
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// how to put items into the data region
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.data
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v1: .word 0x11,0x22,0x33,0x44 // this is same as: int32_t v1[] = {0x11,0x22,0x33,0x44};
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v2: .word 0x11111111,0x22222222,0x33333333,0x44444444 // this is same as: int32_t v2[] = {0x11111111,0x22222222,0x33333333,0x44444444};
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// how to put items into the bss
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.lcomm b1,4 // this is the same as: int32_t b1;
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.lcomm b2,16 // this is the same as: int32_t b2[4];
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