31 lines
893 B
NASM
31 lines
893 B
NASM
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bits 64
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SECTION .data
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; empty
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SECTION .text
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global _start
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_start:
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%include "header.asm.inc"
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mov rax, 0xFFFFFFFFFFFFFFFF ; maxint
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; moving data into sub-registers
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mov al, 0x11 ; rax -> 0xFFFFFFFFFFFFFF11
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mov ah, 0x22 ; rax -> 0xFFFFFFFFFFFF2211
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mov ax, 0x3333 ; rax -> 0xFFFFFFFFFFFF3333
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; There is one exception, though:
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; Intel's reference tells us that "32-bit operands generate
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; a 32-bit result, zero-extended to a 64-bit result in the
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; destination general-purpose register.", thus:
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mov eax, 0x44444444 ; rax -> 0x0000000044444444
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; moving with zero-extension (movzx)
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mov rax, 0xFFFFFFFFFFFFFFFF ; maxint
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mov bx, 0x55
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mov al, bl ; rax -> 0xFFFFFFFFFFFFFF55
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movzx rax, bx ; rax -> 0x0000000000000055
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%include "sysexit.asm.inc"
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