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      1 #include "sljitLir.h"
      2 
      3 #include <stdio.h>
      4 #include <stdlib.h>
      5 
      6 typedef long SLJIT_CALL (*func3_t)(long a, long b, long c);
      7 
      8 /*
      9   This example, we generate a function like this:
     10 
     11 long func(long a, long b, long c)
     12 {
     13 	if ((a & 1) == 0)
     14 		return c;
     15 	return b;
     16 }
     17 
     18  */
     19 static int branch(long a, long b, long c)
     20 {
     21 	void *code;
     22 	unsigned long len;
     23 	func3_t func;
     24 
     25 	struct sljit_jump *ret_c;
     26 	struct sljit_jump *out;
     27 
     28 	/* Create a SLJIT compiler */
     29 	struct sljit_compiler *C = sljit_create_compiler();
     30 
     31 	/* 3 arg, 1 temp reg, 3 save reg */
     32 	sljit_emit_enter(C, 0,  3,  1, 3, 0, 0, 0);
     33 
     34 	/* R0 = a & 1, S0 is argument a */
     35 	sljit_emit_op2(C, SLJIT_AND, SLJIT_R0, 0, SLJIT_S0, 0, SLJIT_IMM, 1);
     36 
     37 	/* if R0 == 0 then jump to ret_c, where is ret_c? we assign it later */
     38 	ret_c = sljit_emit_cmp(C, SLJIT_EQUAL, SLJIT_R0, 0, SLJIT_IMM, 0);
     39 
     40 	/* R0 = b, S1 is argument b */
     41 	sljit_emit_op1(C, SLJIT_MOV, SLJIT_RETURN_REG, 0, SLJIT_S1, 0);
     42 
     43 	/* jump to out */
     44 	out = sljit_emit_jump(C, SLJIT_JUMP);
     45 
     46 	/* here is the 'ret_c' should jump, we emit a label and set it to ret_c */
     47 	sljit_set_label(ret_c, sljit_emit_label(C));
     48 
     49 	/* R0 = c, S2 is argument c */
     50 	sljit_emit_op1(C, SLJIT_MOV, SLJIT_RETURN_REG, 0, SLJIT_S2, 0);
     51 
     52 	/* here is the 'out' should jump */
     53 	sljit_set_label(out, sljit_emit_label(C));
     54 
     55 	/* end of function */
     56 	sljit_emit_return(C, SLJIT_MOV, SLJIT_RETURN_REG, 0);
     57 
     58 	/* Generate machine code */
     59 	code = sljit_generate_code(C);
     60 	len = sljit_get_generated_code_size(C);
     61 
     62 	/* Execute code */
     63 	func = (func3_t)code;
     64 	printf("func return %ld\n", func(a, b, c));
     65 
     66 	/* dump_code(code, len); */
     67 
     68 	/* Clean up */
     69 	sljit_free_compiler(C);
     70 	sljit_free_code(code);
     71 	return 0;
     72 }
     73 
     74 int main()
     75 {
     76 	return branch(4, 5, 6);
     77 }
     78