The ascii generated when the function returns a string type is incorrect

[996ccs]

Question

I wrote a function getA using AssemblyScript to return an A string. After compilation, I got a wasm file. Then I used other wasm runtime to parse the wasm file and called the getA function hoping to get the ascii value 65 corresponding to A. But what I got was [2, 0, 0, 0, 2, 0, 0, 0, 65] The wat file compiled by AssemblyScript is as follows

(module
 (type $0 (func (result i32)))
 (memory $0 1)
 (data $0 (i32.const 1036) "\1c")
 (data $0.1 (i32.const 1048) "\02\00\00\00\02\00\00\00A")
 (export "getA" (func $assembly/index/getA))
 (export "memory" (memory $0))
 (func $assembly/index/getA (result i32)
  i32.const 1056
 )
)

Judging from the compiled product above, the prefix '\02\00\00\00\02\00\00\00' is obviously redundant.

[dcodeIO]

What you are seeing there is a string header, type 2, length 2, data in 16-bit Unicode.

See also: https://www.assemblyscript.org/runtime.html#header-layout

[CountBleck]

Also note that the pointer returned by getA is 1056, which is in the middle of the data segment (at 1048) you're looking at. The location of the A is indeed at 1056, and the managed object header is placed eight bytes before the location referred to by the pointer.

[github-actions]

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