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// Sys.vm for NestedCall test.

// Sys.init()
//
// Calls Sys.main() and stores return value in temp 1.
// Does not return.  (Enters infinite loop.)

function Sys.init 0
push constant 4000	// test THIS and THAT context save
pop pointer 0
push constant 5000
pop pointer 1
call Sys.main 0
pop temp 1
label LOOP
goto LOOP

// Sys.main()
//
// Sets locals 1, 2 and 3, leaving locals 0 and 4 unchanged to test
// default local initialization to 0.  (RAM set to -1 by test setup.)
// Calls Sys.add12(123) and stores return value (135) in temp 0.
// Returns local 0 + local 1 + local 2 + local 3 + local 4 (456) to confirm
// that locals were not mangled by function call.

function Sys.main 5
push constant 4001
pop pointer 0
push constant 5001
pop pointer 1
push constant 200
pop local 1
push constant 40
pop local 2
push constant 6
pop local 3
push constant 123
call Sys.add12 1
pop temp 0
push local 0
push local 1
push local 2
push local 3
push local 4
add
add
add
add
return

// Sys.add12(int n)
//
// Returns n+12.

function Sys.add12 0
push constant 4002
pop pointer 0
push constant 5002
pop pointer 1
push argument 0
push constant 12
add
return