1  #include <stdlib.h>
       2  #include <stdio.h>
       3  #include <string.h>
       4  
       5  #include "libgccjit.h"
       6  
       7  #include "harness.h"
       8  
       9  void
      10  create_code (gcc_jit_context *ctxt, void *user_data)
      11  {
      12    /* Let's try to inject the equivalent of:
      13  
      14        int
      15        my_factorial_must_tail_call (int x)
      16        {
      17          if (x < 2)
      18            return x;
      19          else
      20            return x * my_factorial_must_tail_call (x - 1);
      21        }
      22  
      23       and mark the call as requiring tail-call-optimization.
      24     */
      25    gcc_jit_type *the_type =
      26      gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_INT);
      27    gcc_jit_type *return_type = the_type;
      28  
      29    gcc_jit_param *x =
      30      gcc_jit_context_new_param (ctxt, NULL, the_type, "x");
      31    gcc_jit_param *params[1] = {x};
      32    gcc_jit_function *func =
      33      gcc_jit_context_new_function (ctxt, NULL,
      34  				  GCC_JIT_FUNCTION_EXPORTED,
      35  				  return_type,
      36  				  "my_factorial_must_tail_call",
      37  				  1, params, 0);
      38  
      39    gcc_jit_block *initial =
      40      gcc_jit_function_new_block (func, "initial");
      41    gcc_jit_block *on_true =
      42      gcc_jit_function_new_block (func, "on_true");
      43    gcc_jit_block *on_false =
      44      gcc_jit_function_new_block (func, "on_false");
      45  
      46   /* if (x < 2) */
      47    gcc_jit_block_end_with_conditional (
      48      initial, NULL,
      49      gcc_jit_context_new_comparison (
      50        ctxt, NULL,
      51        GCC_JIT_COMPARISON_LT,
      52        gcc_jit_param_as_rvalue (x),
      53        gcc_jit_context_new_rvalue_from_int (
      54  	ctxt,
      55  	the_type,
      56  	2)),
      57      on_true,
      58      on_false);
      59  
      60    /* true branch: */
      61    /* return x */
      62    gcc_jit_block_end_with_return (
      63      on_true,
      64      NULL,
      65      gcc_jit_param_as_rvalue (x));
      66  
      67    /* false branch: */
      68    gcc_jit_rvalue *x_minus_1 =
      69      gcc_jit_context_new_binary_op (
      70        ctxt, NULL,
      71        GCC_JIT_BINARY_OP_MINUS, the_type,
      72        gcc_jit_param_as_rvalue (x),
      73        gcc_jit_context_new_rvalue_from_int (
      74  	ctxt,
      75  	the_type,
      76  	1));
      77    /* my_factorial_must_tail_call (x - 1) */
      78    gcc_jit_rvalue *call =
      79        gcc_jit_context_new_call (
      80          ctxt, NULL,
      81          func,
      82          1, &x_minus_1);
      83  
      84    /* Mark the call as requiring tail-call optimization.  */
      85    gcc_jit_rvalue_set_bool_require_tail_call (call, 1);
      86  
      87    gcc_jit_block_end_with_return (
      88      on_false,
      89      NULL,
      90      gcc_jit_context_new_binary_op (
      91        ctxt, NULL,
      92        GCC_JIT_BINARY_OP_MULT, the_type,
      93        gcc_jit_param_as_rvalue (x),
      94        call));
      95  }
      96  
      97  void
      98  verify_code (gcc_jit_context *ctxt, gcc_jit_result *result)
      99  {
     100    typedef int (*my_factorial_fn_type) (int);
     101    CHECK_NON_NULL (result);
     102    my_factorial_fn_type my_factorial_must_tail_call =
     103      (my_factorial_fn_type)gcc_jit_result_get_code (result, "my_factorial_must_tail_call");
     104    CHECK_NON_NULL (my_factorial_must_tail_call);
     105    int val = my_factorial_must_tail_call (10);
     106    note ("my_factorial_must_tail_call returned: %d", val);
     107    CHECK_VALUE (val, 3628800);
     108  }
     109