pub fn fnhead_stack<L>(nlocals: u32) -> Item<L>Expand description
Constructs a function header item with the ArgsOnStack calling convention.
Examples found in repository?
examples/hello.rs (line 18)
5fn main() {
6 let main_label = 0;
7 let hello_sailor_label = 1;
8 let fail_label = 2;
9
10 let assembly: Assembly<i32> = Assembly {
11 rom_items: Cow::Owned(vec![
12 // The string we'll print. Add some newlines at the beginning so
13 // that the "game session has ended" message doesn't cover it.
14 label(hello_sailor_label),
15 mystery_string(&"\n\n\nHello, sailor!\n"),
16 // Header for our main function, which uses no locals.
17 label(main_label),
18 fnhead_stack(0),
19 // Set Glk as our IO system.
20 setiosys(imm(2), imm(0)),
21 // Push arguments to create our main window
22 // rock = 0
23 copy(imm(0), push()),
24 // wintype = Textbuffer
25 copy(imm(3), push()),
26 // size = 0 (ignored for root window)
27 copy(imm(0), push()),
28 // method = 0 (ignored for root window)
29 copy(imm(0), push()),
30 // split = 0
31 copy(imm(0), push()),
32 // call glk_window_open (0x23) with these five arguments. Push the
33 // return value to the stack.
34 glk(imm(0x23), imm(5), push()),
35 // Duplicate the return value on the stack.
36 stkcopy(imm(1)),
37 // Jump to fail_label if we got a null return.
38 jz(pop(), fail_label),
39 // Call glk_set_window (0x21) with one argument (the winid that's on
40 // the stack) to set our new window as current.
41 glk(imm(0x2f), imm(1), discard()),
42 // Print our message.
43 streamstr(imml(hello_sailor_label)),
44 // Return from main.
45 label(fail_label),
46 ret(imm(0)),
47 ]),
48 ram_items: Cow::Owned(vec![]),
49 zero_items: Cow::Owned(vec![]),
50 stack_size: 256,
51 start_func: LabelRef(main_label, 0),
52 decoding_table: None,
53 };
54
55 let bytes = assembly.assemble().unwrap();
56 let mut stdout = std::io::stdout();
57 stdout.write_all(&bytes).unwrap();
58}