bpf/progs/btf_dump_test_case_padding.c

0001 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
0002
0003 /*
0004  * BTF-to-C dumper tests for implicit and explicit padding between fields and
0005  * at the end of a struct.
0006  *
0007  * Copyright (c) 2019 Facebook
0008  */
0009 /* ----- START-EXPECTED-OUTPUT ----- */
0010 struct padded_implicitly {
0011     int a;
0012     long b;
0013     char c;
0014 };
0015
0016 /* ------ END-EXPECTED-OUTPUT ------ */
0017
0018 /* ----- START-EXPECTED-OUTPUT ----- */
0019 /*
0020  *struct padded_explicitly {
0021  *  int a;
0022  *  int: 32;
0023  *  int b;
0024  *};
0025  *
0026  */
0027 /* ------ END-EXPECTED-OUTPUT ------ */
0028
0029 struct padded_explicitly {
0030     int a;
0031     int: 1; /* algo will explicitly pad with full 32 bits here */
0032     int b;
0033 };
0034
0035 /* ----- START-EXPECTED-OUTPUT ----- */
0036 /*
0037  *struct padded_a_lot {
0038  *  int a;
0039  *  long: 32;
0040  *  long: 64;
0041  *  long: 64;
0042  *  int b;
0043  *};
0044  *
0045  */
0046 /* ------ END-EXPECTED-OUTPUT ------ */
0047
0048 struct padded_a_lot {
0049     int a;
0050     /* 32 bit of implicit padding here, which algo will make explicit */
0051     long: 64;
0052     long: 64;
0053     int b;
0054 };
0055
0056 /* ----- START-EXPECTED-OUTPUT ----- */
0057 /*
0058  *struct padded_cache_line {
0059  *  int a;
0060  *  long: 32;
0061  *  long: 64;
0062  *  long: 64;
0063  *  long: 64;
0064  *  int b;
0065  *  long: 32;
0066  *  long: 64;
0067  *  long: 64;
0068  *  long: 64;
0069  *};
0070  *
0071  */
0072 /* ------ END-EXPECTED-OUTPUT ------ */
0073
0074 struct padded_cache_line {
0075     int a;
0076     int b __attribute__((aligned(32)));
0077 };
0078
0079 /* ----- START-EXPECTED-OUTPUT ----- */
0080 /*
0081  *struct zone_padding {
0082  *  char x[0];
0083  *};
0084  *
0085  *struct zone {
0086  *  int a;
0087  *  short b;
0088  *  short: 16;
0089  *  struct zone_padding __pad__;
0090  *};
0091  *
0092  */
0093 /* ------ END-EXPECTED-OUTPUT ------ */
0094
0095 struct zone_padding {
0096     char x[0];
0097 } __attribute__((__aligned__(8)));
0098
0099 struct zone {
0100     int a;
0101     short b;
0102     struct zone_padding __pad__;
0103 };
0104
0105 int f(struct {
0106     struct padded_implicitly _1;
0107     struct padded_explicitly _2;
0108     struct padded_a_lot _3;
0109     struct padded_cache_line _4;
0110     struct zone _5;
0111 } *_)
0112 {
0113     return 0;
0114 }