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// hi.s: print "alonzo sucks!" to standard output and then exit.
//
// uses write() and exit() linux system calls directly to elide libc and
// assembles to a static, 384 byte arm64 binary.
// entry point
//
// uses 32-bit registers (wN) instead of 64-bit registers (xN) to
// save a few bytes in the assembled binary
.text
.global _start
_start:
// write(stdout, msg, len)
mov w0, #1 // stdout fd (1)
ldr w1, =msg // message
mov w2, len // message length
mov w8, #64 // write() (64)
svc #0 // call write()
// exit(0)
mov w0, #0 // exit code (0)
mov w8, #93 // exit() (93)
svc #0 // call exit()
// message and message length
//
// technically the message belongs in the .rodata section, but sticking
// it here allows it to be packed after _start and the saves ~60 bytes
// in the assembled binary
msg: .ascii "alonzo sucks!\n" // message (14 bytes)
len = . - msg // message length
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