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array_access.c revision 1.1 
      1 #include "sljitLir.h"
      2 
      3 #include <stdio.h>
      4 #include <stdlib.h>
      5 
      6 typedef long SLJIT_CALL (*func_arr_t)(long *arr, long narr);
      7 
      8 static long SLJIT_CALL print_num(long a)
      9 {
     10 	printf("num = %ld\n", a);
     11 	return a + 1;
     12 }
     13 
     14 /*
     15   This example, we generate a function like this:
     16 
     17 long func(long *array, long narray)
     18 {
     19 	long i;
     20 	for (i = 0; i < narray; ++i)
     21 		print_num(array[i]);
     22 	return narray;
     23 }
     24 
     25 */
     26 
     27 static int array_access(long *arr, long narr)
     28 {
     29 	void *code;
     30 	unsigned long len;
     31 	func_arr_t func;
     32 
     33 	/* Create a SLJIT compiler */
     34 	struct sljit_compiler *C = sljit_create_compiler();
     35 
     36 	sljit_emit_enter(C, 0,  2,  1, 3, 0, 0, 0);
     37 	/*                  opt arg R  S  FR FS local_size */
     38 	sljit_emit_op2(C, SLJIT_XOR, SLJIT_S2, 0, SLJIT_S2, 0, SLJIT_S2, 0);				// S2 = 0
     39 	struct sljit_label *loopstart = sljit_emit_label(C);								// loopstart:
     40 	struct sljit_jump *out = sljit_emit_cmp(C, SLJIT_GREATER_EQUAL, SLJIT_S2, 0, SLJIT_S1, 0);	// S2 >= a --> jump out
     41 
     42 	sljit_emit_op1(C, SLJIT_MOV, SLJIT_R0, 0, SLJIT_MEM2(SLJIT_S0, SLJIT_S2), SLJIT_WORD_SHIFT);// R0 = (long *)S0[S2];
     43 	sljit_emit_ijump(C, SLJIT_CALL1, SLJIT_IMM, SLJIT_FUNC_OFFSET(print_num));					// print_num(R0);
     44 
     45 	sljit_emit_op2(C, SLJIT_ADD, SLJIT_S2, 0, SLJIT_S2, 0, SLJIT_IMM, 1);						// S2 += 1
     46 	sljit_set_label(sljit_emit_jump(C, SLJIT_JUMP), loopstart);									// jump loopstart
     47 	sljit_set_label(out, sljit_emit_label(C));											// out:
     48 	sljit_emit_return(C, SLJIT_MOV, SLJIT_S1, 0);										// return RET
     49 
     50 	/* Generate machine code */
     51 	code = sljit_generate_code(C);
     52 	len = sljit_get_generated_code_size(C);
     53 
     54 	/* Execute code */
     55 	func = (func_arr_t)code;
     56 	printf("func return %ld\n", func(arr, narr));
     57 
     58 	/* dump_code(code, len); */
     59 
     60 	/* Clean up */
     61 	sljit_free_compiler(C);
     62 	sljit_free_code(code);
     63 	return 0;
     64 }
     65 
     66 int main()
     67 {
     68 	long arr[8] = { 3, -10, 4, 6, 8, 12, 2000 };
     69 	return array_access(arr, 8);
     70 }
     71