140 lines
4.9 KiB
Plaintext
140 lines
4.9 KiB
Plaintext
|
|
(let (
|
|
; Vectors and Values
|
|
; Bytes encode themselves
|
|
encode_u_LEB128 (rec-lambda recurse (x)
|
|
(cond (< x 0x80) [x]
|
|
true (cons (| (& x 0x7F) 0x1) (recurse (>> x 8))))
|
|
)
|
|
encode_s8_LEB128 (lambda (x) (encode_u_LEB128 (& x 255)))
|
|
encode_s32_LEB128 (lambda (x) (encode_u_LEB128 (& x 255)))
|
|
encode_vector (lambda (enc v)
|
|
(concat (encode_u_LEB128 (len v)) (flat_map enc v) )
|
|
)
|
|
encode_floating_point (lambda (x) (error "unimplemented"))
|
|
encode_name (lambda (name)
|
|
(encode_vector (lambda (x) [x]) name)
|
|
)
|
|
|
|
; Types
|
|
; TODO
|
|
encode_limits (lambda (x)
|
|
(cond (= 1 (len x)) (concat [0x00] (encode_u_LEB128 (idx x 0)))
|
|
(= 2 (len x)) (concat [0x01] (encode_u_LEB128 (idx x 0)) (encode_u_LEB128 (idx x 1)))
|
|
true (error "trying to encode bad limits"))
|
|
)
|
|
encode_number_type (lambda (x)
|
|
(cond (= x 'i32) [0x7F]
|
|
(= x 'i64) [0x7E]
|
|
(= x 'f32) [0x7D]
|
|
(= x 'f64) [0x7C]
|
|
true (error "bad number type"))
|
|
)
|
|
encode_valtype (lambda (x)
|
|
; we don't handle reference types yet
|
|
(encode_number_type x)
|
|
)
|
|
encode_result_type (lambda (x)
|
|
(encode_vector encode_valtype x)
|
|
)
|
|
encode_function_type (lambda (x)
|
|
(concat [0x60] (encode_result_type (idx x 0))
|
|
(encode_result_type (idx x 1)))
|
|
)
|
|
|
|
; Instructions
|
|
; TODO
|
|
|
|
; Modules
|
|
encode_type_section (lambda (x)
|
|
(let (
|
|
encoded (encode_vector encode_function_type x)
|
|
) (concat [0x01] (encode_u_LEB128 (len encoded)) encoded ))
|
|
)
|
|
encode_memory_section (lambda (x)
|
|
(let (
|
|
encoded (encode_vector encode_limits x)
|
|
) (concat [0x05] (encode_u_LEB128 (len encoded)) encoded ))
|
|
)
|
|
encode_export (lambda (export)
|
|
(let (
|
|
(name type idx) export
|
|
) (concat (encode_name name)
|
|
(cond (= type 'func) [0x00]
|
|
(= type 'table) [0x01]
|
|
(= type 'mem) [0x02]
|
|
(= type 'global) [0x03]
|
|
true (error "bad export type"))
|
|
(encode_u_LEB128 idx)
|
|
))
|
|
)
|
|
encode_export_section (lambda (x)
|
|
(let (
|
|
encoded (encode_vector encode_export x)
|
|
) (concat [0x07] (encode_u_LEB128 (len encoded)) encoded ))
|
|
)
|
|
|
|
encode_function_section (lambda (x)
|
|
(let (
|
|
encoded (encode_vector encode_u_LEB128 x)
|
|
) (concat [0x03] (encode_u_LEB128 (len encoded)) encoded ))
|
|
)
|
|
encode_ins (lambda (ins)
|
|
(let (
|
|
op (idx ins 0)
|
|
) (cond (= op 'unreachable) [0x00]
|
|
(= op 'nop) [0x01]
|
|
; skipping a bunch
|
|
; Parametric Instructions
|
|
(= op 'drop) [0x1A]
|
|
; skip
|
|
; Variable Instructions
|
|
(= op 'local.get) (concat [0x20] (encode_u_LEB128 (idx ins 1)))
|
|
(= op 'local.set) (concat [0x21] (encode_u_LEB128 (idx ins 1)))
|
|
(= op 'local.tee) (concat [0x22] (encode_u_LEB128 (idx ins 1)))
|
|
(= op 'global.get) (concat [0x23] (encode_u_LEB128 (idx ins 1)))
|
|
(= op 'global.set) (concat [0x24] (encode_u_LEB128 (idx ins 1)))
|
|
; skip
|
|
; Numeric Instructions
|
|
(= op 'i32.const) (concat [0x41] (encode_s32_LEB128 (idx ins 1)))
|
|
; skip
|
|
(= op 'i32.add) [0x6A]
|
|
))
|
|
)
|
|
encode_code (lambda (x)
|
|
(let (
|
|
(locals body) x
|
|
enc_locals (encode_vector (lambda (loc)
|
|
(concat (encode_u_LEB128 (idx loc 0)) (encode_u_LEB128 (idx loc 1)))) locals)
|
|
enc_expr (concat (flat_map encode_ins body) [0x0B])
|
|
code_bytes (concat enc_locals enc_expr)
|
|
) (concat (encode_u_LEB128 (len code_bytes)) code_bytes))
|
|
)
|
|
encode_code_section (lambda (x)
|
|
(let (
|
|
encoded (encode_vector encode_code x)
|
|
) (concat [0x0A] (encode_u_LEB128 (len encoded)) encoded ))
|
|
)
|
|
|
|
|
|
wasm_to_binary (lambda (wasm_code)
|
|
(let (
|
|
magic [ 0x00 0x61 0x73 0x6D ]
|
|
version [ 0x01 0x00 0x00 0x00 ]
|
|
type (encode_type_section [ [['i32] ['i32]] ])
|
|
function (encode_function_section [ 0 ])
|
|
memory (encode_memory_section [ [0x20 0x30] ])
|
|
export (encode_export_section [ ["add" 'func 0] ])
|
|
code (encode_code_section [
|
|
[ [] [
|
|
['i32.const 1337]
|
|
['local.get 0]
|
|
['i32.add]
|
|
] ]
|
|
])
|
|
) (concat magic version type function memory export code))
|
|
)
|
|
)
|
|
(provide wasm_to_binary)
|
|
)
|