1/**************************************************************************/
2/* callable_method_pointer.cpp */
3/**************************************************************************/
4/* This file is part of: */
5/* GODOT ENGINE */
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8/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
9/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
10/* */
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29/**************************************************************************/
30
31#include "callable_method_pointer.h"
32
33bool CallableCustomMethodPointerBase::compare_equal(const CallableCustom *p_a, const CallableCustom *p_b) {
34 const CallableCustomMethodPointerBase *a = static_cast<const CallableCustomMethodPointerBase *>(p_a);
35 const CallableCustomMethodPointerBase *b = static_cast<const CallableCustomMethodPointerBase *>(p_b);
36
37 if (a->comp_size != b->comp_size) {
38 return false;
39 }
40
41 // Avoid sorting by memory address proximity, which leads to unpredictable performance over time
42 // due to the reuse of old addresses for newer objects. Use byte-wise comparison to leverage the
43 // backwards encoding of little-endian systems as a way to decouple spatiality and time.
44 return memcmp(a->comp_ptr, b->comp_ptr, a->comp_size * 4) == 0;
45}
46
47bool CallableCustomMethodPointerBase::compare_less(const CallableCustom *p_a, const CallableCustom *p_b) {
48 const CallableCustomMethodPointerBase *a = static_cast<const CallableCustomMethodPointerBase *>(p_a);
49 const CallableCustomMethodPointerBase *b = static_cast<const CallableCustomMethodPointerBase *>(p_b);
50
51 if (a->comp_size != b->comp_size) {
52 return a->comp_size < b->comp_size;
53 }
54
55 // See note in compare_equal().
56 return memcmp(a->comp_ptr, b->comp_ptr, a->comp_size * 4) < 0;
57}
58
59CallableCustom::CompareEqualFunc CallableCustomMethodPointerBase::get_compare_equal_func() const {
60 return compare_equal;
61}
62
63CallableCustom::CompareLessFunc CallableCustomMethodPointerBase::get_compare_less_func() const {
64 return compare_less;
65}
66
67uint32_t CallableCustomMethodPointerBase::hash() const {
68 return h;
69}
70
71void CallableCustomMethodPointerBase::_setup(uint32_t *p_base_ptr, uint32_t p_ptr_size) {
72 comp_ptr = p_base_ptr;
73 comp_size = p_ptr_size / 4;
74
75 // Precompute hash.
76 for (uint32_t i = 0; i < comp_size; i++) {
77 if (i == 0) {
78 h = hash_murmur3_one_32(comp_ptr[i]);
79 } else {
80 h = hash_murmur3_one_32(comp_ptr[i], h);
81 }
82 }
83}
84