From: Pedro Alves Date: Mon, 18 Jul 2022 23:26:33 +0000 (+0100) Subject: struct packed: Unit tests and more operators X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=e249e6b8012ea0a14e5768d31becd7b4caff8e77;p=binutils-gdb.git struct packed: Unit tests and more operators For PR gdb/29373, I wrote an alternative implementation of struct packed that uses a gdb_byte array for internal representation, needed for mingw+clang. While adding that, I wrote some unit tests to make sure both implementations behave the same. While at it, I implemented all relational operators. This commit adds said unit tests and relational operators. The alternative gdb_byte array implementation will come next. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29373 Change-Id: I023315ee03622c59c397bf4affc0b68179c32374 --- diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 57c29a78b7a..aebb7dc5ea3 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -464,6 +464,7 @@ SELFTESTS_SRCS = \ unittests/offset-type-selftests.c \ unittests/observable-selftests.c \ unittests/optional-selftests.c \ + unittests/packed-selftests.c \ unittests/parallel-for-selftests.c \ unittests/parse-connection-spec-selftests.c \ unittests/path-join-selftests.c \ diff --git a/gdb/unittests/packed-selftests.c b/gdb/unittests/packed-selftests.c new file mode 100644 index 00000000000..3438a5a2555 --- /dev/null +++ b/gdb/unittests/packed-selftests.c @@ -0,0 +1,132 @@ +/* Self tests for packed for GDB, the GNU debugger. + + Copyright (C) 2022 Free Software Foundation, Inc. + + This file is part of GDB. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see . */ + +#include "defs.h" +#include "gdbsupport/selftest.h" +#include "gdbsupport/packed.h" + +namespace selftests { +namespace packed_tests { + +enum test_enum +{ + TE_A = 1, + TE_B = 2, + TE_C = 3, + TE_D = 4, +}; + +gdb_static_assert (sizeof (packed) == 1); +gdb_static_assert (sizeof (packed) == 2); +gdb_static_assert (sizeof (packed) == 3); +gdb_static_assert (sizeof (packed) == 4); + +gdb_static_assert (alignof (packed) == 1); +gdb_static_assert (alignof (packed) == 1); +gdb_static_assert (alignof (packed) == 1); +gdb_static_assert (alignof (packed) == 1); + +/* Triviality checks. */ +#define CHECK_TRAIT(TRAIT) \ + static_assert (std::TRAIT>::value, "") + +#if HAVE_IS_TRIVIALLY_COPYABLE + +CHECK_TRAIT (is_trivially_copyable); +CHECK_TRAIT (is_trivially_copy_constructible); +CHECK_TRAIT (is_trivially_move_constructible); +CHECK_TRAIT (is_trivially_copy_assignable); +CHECK_TRAIT (is_trivially_move_assignable); + +#endif + +#undef CHECK_TRAIT + +/* Entry point. */ + +static void +run_tests () +{ + typedef packed packed_2; + + packed_2 p1; + packed_2 p2 (0x0102); + p1 = 0x0102; + + SELF_CHECK (p1 == p1); + SELF_CHECK (p1 == p2); + SELF_CHECK (p1 == 0x0102); + SELF_CHECK (0x0102 == p1); + + SELF_CHECK (p1 != 0); + SELF_CHECK (0 != p1); + + SELF_CHECK (p1 != 0x0103); + SELF_CHECK (0x0103 != p1); + + SELF_CHECK (p1 != 0x01020102); + SELF_CHECK (0x01020102 != p1); + + SELF_CHECK (p1 != 0x01020000); + SELF_CHECK (0x01020000 != p1); + + /* Check truncation. */ + p1 = 0x030102; + SELF_CHECK (p1 == 0x0102); + SELF_CHECK (p1 != 0x030102); + + /* Check that the custom std::atomic/packed/T relational operators + work as intended. No need for fully comprehensive tests, as all + operators are defined in the same way, via a macro. We just want + to make sure that we can compare atomic-wrapped packed, with + packed, and with the packed underlying type. */ + + std::atomic> atomic_packed_2 (0x0102); + + SELF_CHECK (atomic_packed_2 == atomic_packed_2); + SELF_CHECK (atomic_packed_2 == p1); + SELF_CHECK (p1 == atomic_packed_2); + SELF_CHECK (atomic_packed_2 == 0x0102u); + SELF_CHECK (0x0102u == atomic_packed_2); + + SELF_CHECK (atomic_packed_2 >= 0x0102u); + SELF_CHECK (atomic_packed_2 <= 0x0102u); + SELF_CHECK (atomic_packed_2 > 0u); + SELF_CHECK (atomic_packed_2 < 0x0103u); + SELF_CHECK (atomic_packed_2 >= 0u); + SELF_CHECK (atomic_packed_2 <= 0x0102u); + SELF_CHECK (!(atomic_packed_2 > 0x0102u)); + SELF_CHECK (!(atomic_packed_2 < 0x0102u)); + + /* Check std::atomic truncation behaves the same as without + std::atomic. */ + atomic_packed_2 = 0x030102; + SELF_CHECK (atomic_packed_2 == 0x0102u); + SELF_CHECK (atomic_packed_2 != 0x030102u); +} + +} /* namespace packed_tests */ +} /* namespace selftests */ + +void _initialize_packed_selftests (); +void +_initialize_packed_selftests () +{ + selftests::register_test ("packed", selftests::packed_tests::run_tests); +} diff --git a/gdbsupport/packed.h b/gdbsupport/packed.h index 53164a9e0c3..d721b02c056 100644 --- a/gdbsupport/packed.h +++ b/gdbsupport/packed.h @@ -19,6 +19,7 @@ #define PACKED_H #include "traits.h" +#include /* Each instantiation and full specialization of the packed template defines a type that behaves like a given scalar type, but that has @@ -68,37 +69,55 @@ private: T m_val : (Bytes * HOST_CHAR_BIT) ATTRIBUTE_PACKED; }; -/* Add some comparisons between std::atomic> and T. We need - this because the regular comparisons would require two implicit - conversions to go from T to std::atomic>: - - T -> packed - packed -> std::atomic> - - and C++ only does one. */ - -template -bool operator== (T lhs, const std::atomic> &rhs) -{ - return lhs == rhs.load (); -} - -template -bool operator== (const std::atomic> &lhs, T rhs) -{ - return lhs.load () == rhs; -} +/* Add some comparisons between std::atomic> and packed + and T. We need this because even though std::atomic doesn't + define these operators, the relational expressions still work via + implicit conversions. Those wouldn't work when wrapped in packed + without these operators, because they'd require two implicit + conversions to go from T to packed to std::atomic> + (and back), and C++ only does one. */ + +#define PACKED_ATOMIC_OP(OP) \ + template \ + bool operator OP (const std::atomic> &lhs, \ + const std::atomic> &rhs) \ + { \ + return lhs.load () OP rhs.load (); \ + } \ + \ + template \ + bool operator OP (T lhs, const std::atomic> &rhs) \ + { \ + return lhs OP rhs.load (); \ + } \ + \ + template \ + bool operator OP (const std::atomic> &lhs, T rhs) \ + { \ + return lhs.load () OP rhs; \ + } \ + \ + template \ + bool operator OP (const std::atomic> &lhs, \ + packed rhs) \ + { \ + return lhs.load () OP rhs; \ + } \ + \ + template \ + bool operator OP (packed lhs, \ + const std::atomic> &rhs) \ + { \ + return lhs OP rhs.load (); \ + } -template -bool operator!= (T lhs, const std::atomic> &rhs) -{ - return !(lhs == rhs); -} +PACKED_ATOMIC_OP (==) +PACKED_ATOMIC_OP (!=) +PACKED_ATOMIC_OP (>) +PACKED_ATOMIC_OP (<) +PACKED_ATOMIC_OP (>=) +PACKED_ATOMIC_OP (<=) -template -bool operator!= (const std::atomic> &lhs, T rhs) -{ - return !(lhs == rhs); -} +#undef PACKED_ATOMIC_OP #endif