The system call table can be referred to this in Mac /Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX.sdk/usr/include/sys/syscall.h
For the BSD system calls method please refer to https://sigsegv.pl/osx-bsd-syscalls/
whereas #1 is exit system call and #4 is write system call
For the complete ARM64 programming examples for M1 Mac, please refer to this.
https://github.com/below/HelloSilicon
It is important to learn debug skill through assembly language and for mac use lldb to debug, e.g.
(lldb) breakpoint set -f HelloWorld.s -l 14
(lldb) run
(lldb) step
(lldb) register read x16 x0 x1 x2
In order to debug on Mac, the program first must add -g option when compiled/asembled(as) and then must be codesigned and add this codesign command to the makefile
codesign --entitlements entitlements.plist --force -s - $@entitlements.plist add this key.
<key>com.apple.security.get-task-allow</key> <true/>
What about Android Termux App?
pkg install clang
wget https://raw.githubusercontent.com/matja/asm-examples/master/aarch64/hello.aarch64.linux.syscall.gas.asm
gcc -nostdlib -static -nostartfiles -Wl,--entry=_start hello.aarch64.linux.syscall.gas.asm -o hello
./hello
What about gbd debug ?
gcc -nostdlib -static -nostartfiles -Wl,--entry=_start hello.aarch64.linux.syscall.gas.asm -g -o hello
pkg install gdb
objdump -d hello
gdb hello
(gdb) break 1 # set breakpoint
(gdb) run # run
(gdb) step # step
(gdb) info reg general # exam register
ARM Architecture Basic
x0-x30 are 64-bit registers
svc 0 is the system call
x8 determines what we do, e.g. ＃64 write and #93 is exit (for other system call numbers please refer to document)
x8 determines what we do, e.g. ＃64 write and #93 is exit (for other system call numbers please refer to document)
x8 determines what we do, e.g. ＃64 is write and #93 is exit (for other system call numbers please refer to this document)
x0-x4 determines how we do it and the required parameters are also documented in the document above.
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