1//===-- Unittests for a freestore -------------------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include <stddef.h>
10
11#include "src/__support/freestore.h"
12#include "test/UnitTest/Test.h"
13
14using LIBC_NAMESPACE::Block;
15using LIBC_NAMESPACE::FreeList;
16using LIBC_NAMESPACE::FreeStore;
17using LIBC_NAMESPACE::FreeTrie;
18using LIBC_NAMESPACE::cpp::byte;
19using LIBC_NAMESPACE::cpp::optional;
20
21// Inserting or removing blocks too small to be tracked does nothing.
22TEST(LlvmLibcFreeStore, TooSmall) {
23 byte mem[1024];
24 optional<Block *> maybeBlock = Block::init(mem);
25 ASSERT_TRUE(maybeBlock.has_value());
26 Block *too_small = *maybeBlock;
27 maybeBlock = too_small->split(Block::PREV_FIELD_SIZE);
28 ASSERT_TRUE(maybeBlock.has_value());
29 // On platforms with high alignment the smallest legal block may be large
30 // enough for a node.
31 if (too_small->outer_size() >= sizeof(Block) + sizeof(FreeList::Node))
32 return;
33 Block *remainder = *maybeBlock;
34
35 FreeStore store;
36 store.set_range({0, 4096});
37 store.insert(too_small);
38 store.insert(remainder);
39
40 EXPECT_EQ(store.remove_best_fit(too_small->inner_size()), remainder);
41 store.remove(too_small);
42}
43
44TEST(LlvmLibcFreeStore, RemoveBestFit) {
45 byte mem[1024];
46 optional<Block *> maybeBlock = Block::init(mem);
47 ASSERT_TRUE(maybeBlock.has_value());
48
49 Block *smallest = *maybeBlock;
50 maybeBlock = smallest->split(sizeof(FreeList::Node) + Block::PREV_FIELD_SIZE);
51 ASSERT_TRUE(maybeBlock.has_value());
52
53 Block *largest_small = *maybeBlock;
54 maybeBlock = largest_small->split(
55 sizeof(FreeTrie::Node) + Block::PREV_FIELD_SIZE - alignof(max_align_t));
56 ASSERT_TRUE(maybeBlock.has_value());
57 if (largest_small->inner_size() == smallest->inner_size())
58 largest_small = smallest;
59 ASSERT_GE(largest_small->inner_size(), smallest->inner_size());
60
61 Block *remainder = *maybeBlock;
62
63 FreeStore store;
64 store.set_range({0, 4096});
65 store.insert(smallest);
66 if (largest_small != smallest)
67 store.insert(largest_small);
68 store.insert(remainder);
69
70 // Find exact match for smallest.
71 ASSERT_EQ(store.remove_best_fit(smallest->inner_size()), smallest);
72 store.insert(smallest);
73
74 // Find exact match for largest.
75 ASSERT_EQ(store.remove_best_fit(largest_small->inner_size()), largest_small);
76 store.insert(largest_small);
77
78 // Search small list for best fit.
79 Block *next_smallest = largest_small == smallest ? remainder : largest_small;
80 ASSERT_EQ(store.remove_best_fit(smallest->inner_size() + 1), next_smallest);
81 store.insert(next_smallest);
82
83 // Continue search for best fit to large blocks.
84 EXPECT_EQ(store.remove_best_fit(largest_small->inner_size() + 1), remainder);
85}
86
87TEST(LlvmLibcFreeStore, Remove) {
88 byte mem[1024];
89 optional<Block *> maybeBlock = Block::init(mem);
90 ASSERT_TRUE(maybeBlock.has_value());
91
92 Block *small = *maybeBlock;
93 maybeBlock = small->split(sizeof(FreeList::Node) + Block::PREV_FIELD_SIZE);
94 ASSERT_TRUE(maybeBlock.has_value());
95
96 Block *remainder = *maybeBlock;
97
98 FreeStore store;
99 store.set_range({0, 4096});
100 store.insert(small);
101 store.insert(remainder);
102
103 store.remove(remainder);
104 ASSERT_EQ(store.remove_best_fit(remainder->inner_size()),
105 static_cast<Block *>(nullptr));
106 store.remove(small);
107 ASSERT_EQ(store.remove_best_fit(small->inner_size()),
108 static_cast<Block *>(nullptr));
109}
110

source code of libc/test/src/__support/freestore_test.cpp