doc/tutorial/first_program.c

   1 #include "sljitLir.h"
   2
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5
   6 typedef long (SLJIT_FUNC *func3_t)(long a, long b, long c);
   7
   8 static int add3(long a, long b, long c)
   9 {
  10         void *code;
  11         unsigned long len;
  12         func3_t func;
  13
  14         /* Create a SLJIT compiler */
  15         struct sljit_compiler *C = sljit_create_compiler(NULL, NULL);
  16
  17         /* Start a context(function entry), have 3 arguments, discuss later */
  18         sljit_emit_enter(C, 0, SLJIT_ARGS3(W, W, W, W), 1, 3, 0, 0, 0);
  19
  20         /* The first arguments of function is register SLJIT_S0, 2nd, SLJIT_S1, etc.  */
  21         /* R0 = first */
  22         sljit_emit_op1(C, SLJIT_MOV, SLJIT_R0, 0, SLJIT_S0, 0);
  23
  24         /* R0 = R0 + second */
  25         sljit_emit_op2(C, SLJIT_ADD, SLJIT_R0, 0, SLJIT_R0, 0, SLJIT_S1, 0);
  26
  27         /* R0 = R0 + third */
  28         sljit_emit_op2(C, SLJIT_ADD, SLJIT_R0, 0, SLJIT_R0, 0, SLJIT_S2, 0);
  29
  30         /* This statement mov R0 to RETURN REG and return */
  31         /* in fact, R0 is RETURN REG itself */
  32         sljit_emit_return(C, SLJIT_MOV, SLJIT_R0, 0);
  33
  34         /* Generate machine code */
  35         code = sljit_generate_code(C);
  36         len = sljit_get_generated_code_size(C);
  37
  38         /* Execute code */
  39         func = (func3_t)code;
  40         printf("func return %ld\n", func(a, b, c));
  41
  42         /* dump_code(code, len); */
  43
  44         /* Clean up */
  45         sljit_free_compiler(C);
  46         sljit_free_code(code, NULL);
  47         return 0;
  48 }
  49
  50 int main()
  51 {
  52         return add3(4, 5, 6);
  53 }