51 lines
920 B
ArmAsm
51 lines
920 B
ArmAsm
/* https://github.com/cirosantilli/x86-bare-metal-examples# */
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#include "common.h"
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BEGIN
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CLEAR
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/* It is not possible to encode moving immediates
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* to segment registers: we must either:
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*
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* * pass through a general register ax
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* * pop from the stack
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*/
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mov $1, %ax
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mov %ax, %ds
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mov %ds:msg, %al
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PUTC <%al>
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/* %ds is the default segment for GAS memory operations
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* if we don't write it explicitly.
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*/
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mov msg, %al
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PUTC <%al>
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mov $1, %ax
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mov %ax, %es
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mov %es:msg, %al
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PUTC <%al>
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mov $1, %ax
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mov %ax, %fs
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mov %fs:msg, %al
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PUTC <%al>
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mov $1, %ax
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mov %ax, %gs
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mov %gs:msg, %al
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PUTC <%al>
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mov $1, %ax
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mov %ax, %ss
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mov %ss:msg, %al
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PUTC <%al>
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hlt
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msg:
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/* Push the correct A forward 16 bytes in memory
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* to compensate for the segments.
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*/
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.fill 0x10
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.byte 'A'
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