Files
Odin/base/runtime/entry_unix_no_crt_amd64.asm
Jeroen van Rijn 393e00bec3 Placate linker
2025-07-31 16:40:40 +02:00

44 lines
1.1 KiB
NASM

bits 64
extern _start_odin
global _start
section .note.GNU-stack
section .text
;; Entry point for programs that specify -no-crt option
;; This entry point should be compatible with dynamic loaders on linux
;; The parameters the dynamic loader passes to the _start function:
;; RDX = pointer to atexit function
;; The stack layout is as follows:
;; +-------------------+
;; NULL
;; +-------------------+
;; envp[m]
;; +-------------------+
;; ...
;; +-------------------+
;; envp[0]
;; +-------------------+
;; NULL
;; +-------------------+
;; argv[n]
;; +-------------------+
;; ...
;; +-------------------+
;; argv[0]
;; +-------------------+
;; argc
;; +-------------------+ <------ RSP
;;
_start:
;; Mark stack frame as the top of the stack
xor rbp, rbp
;; Load argc into 1st param reg, argv into 2nd param reg
pop rdi
mov rsi, rsp
;; Align stack pointer down to 16-bytes (sysv calling convention)
and rsp, -16
;; Call into odin entry point
call _start_odin
jmp $$