tools/testing/selftests/bpf/progs/btf_dump_test_case_padding.c

   1 // SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
   2
   3 /*
   4  * BTF-to-C dumper tests for implicit and explicit padding between fields and
   5  * at the end of a struct.
   6  *
   7  * Copyright (c) 2019 Facebook
   8  */
   9 /* ----- START-EXPECTED-OUTPUT ----- */
  10 struct padded_implicitly {
  11         int a;
  12         long int b;
  13         char c;
  14 };
  15
  16 /* ------ END-EXPECTED-OUTPUT ------ */
  17
  18 /* ----- START-EXPECTED-OUTPUT ----- */
  19 /*
  20  *struct padded_explicitly {
  21  *      int a;
  22  *      int: 32;
  23  *      int b;
  24  *};
  25  *
  26  */
  27 /* ------ END-EXPECTED-OUTPUT ------ */
  28
  29 struct padded_explicitly {
  30         int a;
  31         int: 1; /* algo will explicitly pad with full 32 bits here */
  32         int b;
  33 };
  34
  35 /* ----- START-EXPECTED-OUTPUT ----- */
  36 /*
  37  *struct padded_a_lot {
  38  *      int a;
  39  *      long: 32;
  40  *      long: 64;
  41  *      long: 64;
  42  *      int b;
  43  *};
  44  *
  45  */
  46 /* ------ END-EXPECTED-OUTPUT ------ */
  47
  48 struct padded_a_lot {
  49         int a;
  50         /* 32 bit of implicit padding here, which algo will make explicit */
  51         long: 64;
  52         long: 64;
  53         int b;
  54 };
  55
  56 /* ----- START-EXPECTED-OUTPUT ----- */
  57 /*
  58  *struct padded_cache_line {
  59  *      int a;
  60  *      long: 32;
  61  *      long: 64;
  62  *      long: 64;
  63  *      long: 64;
  64  *      int b;
  65  *};
  66  *
  67  */
  68 /* ------ END-EXPECTED-OUTPUT ------ */
  69
  70 struct padded_cache_line {
  71         int a;
  72         int b __attribute__((aligned(32)));
  73 };
  74
  75 /* ----- START-EXPECTED-OUTPUT ----- */
  76 /*
  77  *struct zone_padding {
  78  *      char x[0];
  79  *};
  80  *
  81  *struct zone {
  82  *      int a;
  83  *      short b;
  84  *      short: 16;
  85  *      struct zone_padding __pad__;
  86  *};
  87  *
  88  */
  89 /* ------ END-EXPECTED-OUTPUT ------ */
  90
  91 struct zone_padding {
  92         char x[0];
  93 } __attribute__((__aligned__(8)));
  94
  95 struct zone {
  96         int a;
  97         short b;
  98         short: 16;
  99         struct zone_padding __pad__;
 100 };
 101
 102 int f(struct {
 103         struct padded_implicitly _1;
 104         struct padded_explicitly _2;
 105         struct padded_a_lot _3;
 106         struct padded_cache_line _4;
 107         struct zone _5;
 108 } *_)
 109 {
 110         return 0;
 111 }