1//===-- Unittests for memalignment ----------------------------------------===//
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 "src/stdlib/memalignment.h"
10#include "test/UnitTest/Test.h"
11
12#include <stdint.h>
13
14TEST(LlvmLibcMemAlignmentTest, NullPointer) {
15 void *ptr = nullptr;
16 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr), static_cast<size_t>(0));
17}
18
19TEST(LlvmLibcMemAlignmentTest, SpecificAlignment) {
20
21 // These addresses have known alignment patterns - if we can construct them
22 uintptr_t addr_align2 = 0x2; // 2-byte aligned
23 uintptr_t addr_align4 = 0x4; // 4-byte aligned
24 uintptr_t addr_align8 = 0x8; // 8-byte aligned
25 uintptr_t addr_align16 = 0x10; // 16-byte aligned
26 uintptr_t addr_align32 = 0x20; // 32-byte aligned
27
28 void *ptr_align2 = reinterpret_cast<void *>(addr_align2);
29 void *ptr_align4 = reinterpret_cast<void *>(addr_align4);
30 void *ptr_align8 = reinterpret_cast<void *>(addr_align8);
31 void *ptr_align16 = reinterpret_cast<void *>(addr_align16);
32 void *ptr_align32 = reinterpret_cast<void *>(addr_align32);
33
34 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_align2), static_cast<size_t>(2));
35 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_align4), static_cast<size_t>(4));
36 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_align8), static_cast<size_t>(8));
37 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_align16), static_cast<size_t>(16));
38 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_align32), static_cast<size_t>(32));
39
40 uintptr_t addr_complex = 0x1234560; // 16-byte aligned (ends in 0)
41 void *ptr_complex = reinterpret_cast<void *>(addr_complex);
42 EXPECT_EQ(LIBC_NAMESPACE::memalignment(ptr_complex), static_cast<size_t>(32));
43}
44
45TEST(LlvmLibcMemAlignmentTest, AlignasSpecifiedAlignment) {
46 alignas(16) static int aligned_16;
47 alignas(32) static int aligned_32;
48 alignas(64) static int aligned_64;
49 alignas(128) static int aligned_128;
50 alignas(256) static int aligned_256;
51
52 EXPECT_GE(LIBC_NAMESPACE::memalignment(&aligned_16), static_cast<size_t>(16));
53 EXPECT_GE(LIBC_NAMESPACE::memalignment(&aligned_32), static_cast<size_t>(32));
54 EXPECT_GE(LIBC_NAMESPACE::memalignment(&aligned_64), static_cast<size_t>(64));
55 EXPECT_GE(LIBC_NAMESPACE::memalignment(&aligned_128),
56 static_cast<size_t>(128));
57 EXPECT_GE(LIBC_NAMESPACE::memalignment(&aligned_256),
58 static_cast<size_t>(256));
59}
60

source code of libc/test/src/stdlib/memalignment_test.cpp