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Invalid parsing of PUSHINT #8

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ProgramCrafter opened this issue Jan 18, 2023 · 2 comments
Open

Invalid parsing of PUSHINT #8

ProgramCrafter opened this issue Jan 18, 2023 · 2 comments

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@ProgramCrafter
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PUSHINT 10 is shown as -6 PUSHINT.

Example contract: https://tonscan.org/address/EQArNPVIjXw_ffWPuGp_61zWtIH3tzBTBnHe9ToZ4m8OkoNf#source
Code displayed on tonscan:

SETCP0
(:methods
  recv_internal: 

  recv_external: 
    3 BLKDROP
    10000000 PUSHINT
    LESS
    IFRET
    ACCEPT
    0 PUSHINT
    -6 PUSHINT
...

Code displayed on dton.io:

SETCP 0
DICTPUSHCONST 19, (xC_)
DICTIGETJMPZ {
  -1 => <{
    BLKDROP 3
    PUSHINT 10000000
    LESS
    IFRET
    ACCEPT
    PUSHINT 0
    PUSHINT 10
...

The relevant part of contract code uses only 10 and not -6:

() recv_external(int balance, int msg_value, cell msg_full, slice in_msg) {
  if (balance < 10 * 1000 * 1000) { return (); }
  accept_message();
  
  send_raw_message(begin_cell()
    .store_uint(0xA, 4)
  ...
@ProgramCrafter
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However, the most interesting thing is that 12 PUSHINT is handled correctly. This can be seen on https://tonscan.org/address/EQA-dgYSkIiw2J-MJ-0shgp1pzcmnoWo_vfd_240X7VDKuhf#source.

@ProgramCrafter
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This is related to incorrect handling of short ints.

According to TVM instructions, short PUSHINT

Pushes integer x into the stack. -5 <= x <= 10.
Here i equals four lower-order bits of x (i=x mod 16).

let x = slice.loadInt(4)

And instruction handler just loads 4-bit int.

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