fork download
copy 
  1. #include <stdio.h>
  2. #include <stdlib.h>
  3. #include <time.h>
  4.  
  5. typedef enum
  6. {
  7.   InstrNop,
  8.   InstrHalt,
  9.   InstrSetVarNum,
  10.   InstrJumpVarZero,
  11.   InstrJumpVarNonzero,
  12.   InstrJump,
  13.   InstrIncVar,
  14.   InstrDecVar,
  15.   InstrXorVarNum,
  16. } tInstr;
  17.  
  18. int ExecuteInstruction(unsigned* Vars, const unsigned* Program, unsigned* Position)
  19. {
  20.   switch (Program[*Position])
  21.   {
  22.   default:
  23.   case InstrHalt:
  24.     return 0;
  25.  
  26.   case InstrNop:
  27.     (*Position)++;
  28.     break;
  29.  
  30.   case InstrSetVarNum:
  31.     Vars[Program[*Position + 1]] = Program[*Position + 2];
  32.     (*Position) += 3;
  33.     break;
  34.  
  35.   case InstrXorVarNum:
  36.     Vars[Program[*Position + 1]] ^= Program[*Position + 2];
  37.     (*Position) += 3;
  38.     break;
  39.  
  40.   case InstrJumpVarZero:
  41.     if (Vars[Program[*Position + 1]] == 0)
  42.       (*Position) = Program[*Position + 2];
  43.     else
  44.       (*Position) += 3;
  45.     break;
  46.  
  47.   case InstrJumpVarNonzero:
  48.     if (Vars[Program[*Position + 1]] != 0)
  49.       (*Position) = Program[*Position + 2];
  50.     else
  51.       (*Position) += 3;
  52.     break;
  53.  
  54.   case InstrJump:
  55.     (*Position) = Program[*Position + 1];
  56.     break;
  57.  
  58.   case InstrIncVar:
  59.     Vars[Program[*Position + 1]]++;
  60.     (*Position) += 2;
  61.     break;
  62.  
  63.   case InstrDecVar:
  64.     Vars[Program[*Position + 1]]--;
  65.     (*Position) += 2;
  66.     break;
  67.   }
  68.  
  69.   return 1;
  70. }
  71.  
  72. typedef enum
  73. {
  74.   VarGlobal,
  75.  
  76.   VarCnt0,
  77.   VarCnt1,
  78.  
  79.   VarFlag0,
  80.   VarFlag1,
  81.   VarTurn,
  82.  
  83.   VarIdxMax
  84. } tVarIdx;
  85.  
  86. unsigned Vars[VarIdxMax];
  87.  
  88. #define USE_PETERSON 0
  89. #define SWAP_CHECKS 0
  90.  
  91. const unsigned Program0[] =
  92. {
  93.   // cnt0 = 1000;
  94.   InstrSetVarNum, VarCnt0, 1000,
  95.  
  96. // 3:
  97. #if USE_PETERSON
  98.   // flag[0] = 1;
  99.   InstrSetVarNum, VarFlag0, 1,
  100.   // turn = 1;
  101.   InstrSetVarNum, VarTurn, 1,
  102. // 9:
  103.   // while (flag[1] == 1 && turn == 1) {}
  104. #if SWAP_CHECKS
  105.   InstrJumpVarZero, VarTurn, 17,
  106.   InstrJumpVarZero, VarFlag1, 17,
  107. #else
  108.   InstrJumpVarZero, VarFlag1, 17,
  109.   InstrJumpVarZero, VarTurn, 17,
  110. #endif
  111.   InstrJump, 9,
  112. // 17:
  113. #endif
  114.  
  115. // Critical section starts
  116.   // global ^= 0x5555;
  117.   // global ^= 0x5555;
  118.   // global++;
  119.   InstrXorVarNum, VarGlobal, 0x5555,
  120.   InstrXorVarNum, VarGlobal, 0x5555,
  121.   InstrIncVar, VarGlobal,
  122. // Critical section ends
  123.  
  124. #if USE_PETERSON
  125.   // flag[0] = 0;
  126.   InstrSetVarNum, VarFlag0, 0,
  127. #endif
  128.  
  129.   // cnt0--;
  130.   InstrDecVar, VarCnt0,
  131.   // if (cnt0 == 0) goto 3;
  132.   InstrJumpVarNonzero, VarCnt0, 3,
  133.  
  134.   // end
  135.   InstrHalt
  136. };
  137.  
  138. const unsigned Program1[] =
  139. {
  140.   // cnt1 = 1000;
  141.   InstrSetVarNum, VarCnt1, 1000,
  142.  
  143. // 3:
  144. #if USE_PETERSON
  145.   // flag[1] = 1;
  146.   InstrSetVarNum, VarFlag1, 1,
  147.   // turn = 0;
  148.   InstrSetVarNum, VarTurn, 0,
  149. // 9:
  150.   // while (flag[0] == 1 && turn == 0) {}
  151. #if SWAP_CHECKS
  152.   InstrJumpVarNonzero, VarTurn, 17,
  153.   InstrJumpVarZero, VarFlag0, 17,
  154. #else
  155.   InstrJumpVarZero, VarFlag0, 17,
  156.   InstrJumpVarNonzero, VarTurn, 17,
  157. #endif
  158.   InstrJump, 9,
  159. // 17:
  160. #endif
  161.  
  162. // Critical section starts
  163.   // global ^= 0xAAAA;
  164.   // global ^= 0xAAAA;
  165.   // global++;
  166.   InstrXorVarNum, VarGlobal, 0xAAAA,
  167.   InstrXorVarNum, VarGlobal, 0xAAAA,
  168.   InstrIncVar, VarGlobal,
  169. // Critical section ends
  170.  
  171. #if USE_PETERSON
  172.   // flag[1] = 0;
  173.   InstrSetVarNum, VarFlag1, 0,
  174. #endif
  175.  
  176.   // cnt1--;
  177.   InstrDecVar, VarCnt1,
  178.   // if (cnt1 == 0) goto 3;
  179.   InstrJumpVarNonzero, VarCnt1, 3,
  180.  
  181.   // end
  182.   InstrHalt
  183. };
  184.  
  185. void Simulate(void)
  186. {
  187.   unsigned pos0 = 0, pos1 = 0;
  188.  
  189.   while (Program0[pos0] != InstrHalt ||
  190.          Program1[pos1] != InstrHalt)
  191.   {
  192.     int cnt;
  193.  
  194.     cnt = rand() % 50;
  195.     while (cnt--)
  196.       if (!ExecuteInstruction(Vars, Program0, &pos0))
  197.         break;
  198.  
  199.     cnt = rand() % 50;
  200.     while (cnt--)
  201.       if (!ExecuteInstruction(Vars, Program1, &pos1))
  202.         break;
  203.   }
  204. }
  205.  
  206. int main(void)
  207. {
  208.   srand(time(NULL));
  209.   Simulate();
  210.   printf("VarGlobal = %u\n", Vars[VarGlobal]);
  211.   return 0;
  212. }
  213.  
Success #stdin #stdout 0s 1832KB
comments (?)
stdin
copy 
Standard input is empty
stdout
copy 
VarGlobal = 1610
https://ideone.com/g8LHp2
language:
C99 (gcc 8.3)
created:
11 years ago
visibility:
public

Share or Embed source code

Discover > Sphere Engine API

The brand new service which powers Ideone!

Discover > IDE Widget

Widget for compiling and running the source code in a web browser!