[PATCH 0/8] Optimize more type traits

[Ken Matsui <kmatsui@gcc.gnu.org>]

This patch series implements __is_const, __is_volatile, __is_pointer,
and __is_unbounded_array built-in traits, which were isolated from my
previous patch series "Optimize type traits compilation performance"
because they contained performance regression.  I confirmed that this
patch series does not cause any performance regression.  The main reason
of the performance regression were the exhaustiveness of the benchmarks
and the instability of the benchmark results.  Here are new benchmark
results:

is_const: https://github.com/ken-matsui/gcc-bench/blob/main/is_const.md#sat-dec-23-090605-am-pst-2023

time: -4.36603%, peak memory: -0.300891%, total memory: -0.247934%

is_volatile_v: https://github.com/ken-matsui/gcc-bench/blob/main/is_volatile_v.md#sat-dec-23-091518-am-pst-2023

time: -4.06816%, peak memory: -0.609298%, total memory: -0.659134%

is_pointer: https://github.com/ken-matsui/gcc-bench/blob/main/is_pointer.md#sat-dec-23-124903-pm-pst-2023

time: -2.47124%, peak memory: -2.98207%, total memory: -4.0811%

is_unbounded_array_v: https://github.com/ken-matsui/gcc-bench/blob/main/is_unbounded_array_v.md#sat-dec-23-010046-pm-pst-2023

time: -1.50025%, peak memory: -1.07386%, total memory: -2.32394%

Ken Matsui (8):
  c++: Implement __is_const built-in trait
  libstdc++: Optimize std::is_const compilation performance
  c++: Implement __is_volatile built-in trait
  libstdc++: Optimize std::is_volatile compilation performance
  c++: Implement __is_pointer built-in trait
  libstdc++: Optimize std::is_pointer compilation performance
  c++: Implement __is_unbounded_array built-in trait
  libstdc++: Optimize std::is_unbounded_array compilation performance

 gcc/cp/constraint.cc                          | 12 +++
 gcc/cp/cp-trait.def                           |  4 +
 gcc/cp/semantics.cc                           | 16 ++++
 gcc/testsuite/g++.dg/ext/has-builtin-1.C      | 12 +++
 gcc/testsuite/g++.dg/ext/is_const.C           | 19 +++++
 gcc/testsuite/g++.dg/ext/is_pointer.C         | 51 +++++++++++++
 gcc/testsuite/g++.dg/ext/is_unbounded_array.C | 37 ++++++++++
 gcc/testsuite/g++.dg/ext/is_volatile.C        | 19 +++++
 libstdc++-v3/include/bits/cpp_type_traits.h   | 29 ++++++++
 libstdc++-v3/include/std/type_traits          | 73 +++++++++++++++++--
 10 files changed, 264 insertions(+), 8 deletions(-)
 create mode 100644 gcc/testsuite/g++.dg/ext/is_const.C
 create mode 100644 gcc/testsuite/g++.dg/ext/is_pointer.C
 create mode 100644 gcc/testsuite/g++.dg/ext/is_unbounded_array.C
 create mode 100644 gcc/testsuite/g++.dg/ext/is_volatile.C

-- 
2.43.0