Simulide 1.0.0, AVR core incorrectly executes instruction CP

Hello.

Simulide version 1.0.0, the AVR kernel incorrectly executes the CP instruction, namely, the "S" flag is incorrectly set, which is why the signed comparison does not work correctly. Version 0.4.15-SR10 works correctly. Here is the test (arduino):

Code:

void setup() {
  Serial.begin(115200);
  int8_t a = 64, b = -64;
  Serial.print(a);
  Serial.print(' ');
  Serial.print(b);
  Serial.print(' ');
  asm volatile(
    "  cp %0, %1\n"
    "  brge m1\n"
    "  ldi %0,0\n"
    "m1:\n"
    "  in %1,__SREG__\n"
    : "+r" (a), "+r" (b)
  );
  Serial.print(a);
  Serial.print(' ');
  Serial.println(b, HEX);
}
void loop()
{
}


The sketch performs a signed comparison of "a" and "b", and if "a" is less than "b, then "a" is zeroed. In "b" writes the state of the register SREG.
Simulide 1.0.0 writes: 64 -64 0 FFFFFF9D
Simulide 0.4.15-SR10 writes: 64 -64 64 FFFFFF8D
Real Arduino writes: 64 -64 64 FFFFFF8D

The bug in the file src/mcusim/cores/avr/avrcore.cpp, line 54:

Code:

write_S_Bit( S_S, sn ^ STATUS(S_V) );

This XOR instruction does not work correctly, "sn" contains flag "N" in bit 7, but "STATUS(S_V)" returns state of flag "V" in the bit 3. This can be rewritten, for example, like this:

Code:

write_S_Bit( S_S, static_cast<bool>(sn) ^ static_cast<bool>(STATUS(S_V)) );

But maybe you will find a better solution.

Thanks, I think it is solved at Rev 1131.