github.com/llvm-mirror/llgo@v0.0.0-20190322182713-bf6f0a60fce1/third_party/gofrontend/libgo/runtime/go-eface-compare.c (about)

     1  /* go-eface-compare.c -- compare two empty values.
     2  
     3     Copyright 2010 The Go Authors. All rights reserved.
     4     Use of this source code is governed by a BSD-style
     5     license that can be found in the LICENSE file.  */
     6  
     7  #include "runtime.h"
     8  #include "go-type.h"
     9  #include "interface.h"
    10  
    11  /* Compare two interface values.  Return 0 for equal, not zero for not
    12     equal (return value is like strcmp).  */
    13  
    14  intgo
    15  __go_empty_interface_compare (struct __go_empty_interface left,
    16  			      struct __go_empty_interface right)
    17  {
    18    const struct __go_type_descriptor *left_descriptor;
    19  
    20    left_descriptor = left.__type_descriptor;
    21  
    22    if (left_descriptor == NULL && right.__type_descriptor == NULL)
    23      return 0;
    24    if (left_descriptor == NULL || right.__type_descriptor == NULL)
    25      return 1;
    26    if (!__go_type_descriptors_equal (left_descriptor,
    27  				    right.__type_descriptor))
    28      return 1;
    29    if (__go_is_pointer_type (left_descriptor))
    30      return left.__object == right.__object ? 0 : 1;
    31    if (!__go_call_equalfn (left_descriptor->__equalfn, left.__object,
    32  			  right.__object, left_descriptor->__size))
    33      return 1;
    34    return 0;
    35  }