Hi!
The following patch is partially a workaround for bogus warnings
when the compiler isn't able to fold _M_disjunct call into constant
false, but also an optimization attempt - assuming _M_disjunct (__s)
is rare, the patch should shrink code size for the common case and
use library or for non-standard instantiations an out of line
function to handle the rare case.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2022-07-27 Jakub Jelinek <ja...@redhat.com>
PR tree-optimization/105329
* acinclude.m4 (libtool_VERSION): Change to 6:31:0.
* config/abi/pre/gnu.ver (GLIBCXX_3.4.21): Don't export
std::basic_string methods with name length of 15.
(GLIBCXX_3.4.31): Export std::basic_string::_M_replace_cold.
* testsuite/util/testsuite_abi.cc (check_version): Handle
GLIBCXX_3.4.31.
* include/bits/basic_string.h (std::basic_string::_M_replace_cold):
Declare.
* include/bits/basic_string.tcc (std::basic_string::_M_replace_cold):
Define and export even for C++20.
(std::basic_string::_M_replace): Use __builtin_expect, outline
the overlapping case to _M_replace_cold.
* configure: Regenerated.
--- libstdc++-v3/acinclude.m4.jj 2022-06-27 11:18:03.102052967 +0200
+++ libstdc++-v3/acinclude.m4 2022-07-26 13:15:51.187572177 +0200
@@ -3821,7 +3821,7 @@ changequote([,])dnl
fi
# For libtool versioning info, format is CURRENT:REVISION:AGE
-libtool_VERSION=6:30:0
+libtool_VERSION=6:31:0
# Everything parsed; figure out what files and settings to use.
case $enable_symvers in
--- libstdc++-v3/config/abi/pre/gnu.ver.jj 2022-03-17 09:22:50.135144471
+0100
+++ libstdc++-v3/config/abi/pre/gnu.ver 2022-07-26 13:12:13.098402944 +0200
@@ -1736,7 +1736,7 @@ GLIBCXX_3.4.21 {
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE12_M*;
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE13*;
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE14_M_replace_aux*;
- _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE1[568-9]*;
+ _ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE1[68-9]*;
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE2at*;
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE3end*;
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE4back*;
@@ -2444,6 +2444,10 @@ GLIBCXX_3.4.30 {
} GLIBCXX_3.4.29;
+GLIBCXX_3.4.31 {
+
_ZNSt7__cxx1112basic_stringI[cw]St11char_traitsI[cw]ESaI[cw]EE15_M_replace_cold*;
+} GLIBCXX_3.4.30;
+
# Symbols in the support library (libsupc++) have their own tag.
CXXABI_1.3 {
--- libstdc++-v3/testsuite/util/testsuite_abi.cc.jj 2022-03-17
09:22:50.135144471 +0100
+++ libstdc++-v3/testsuite/util/testsuite_abi.cc 2022-07-26
13:16:44.042886118 +0200
@@ -211,6 +211,7 @@ check_version(symbol& test, bool added)
known_versions.push_back("GLIBCXX_3.4.28");
known_versions.push_back("GLIBCXX_3.4.29");
known_versions.push_back("GLIBCXX_3.4.30");
+ known_versions.push_back("GLIBCXX_3.4.31");
known_versions.push_back("GLIBCXX_LDBL_3.4.29");
known_versions.push_back("GLIBCXX_IEEE128_3.4.29");
known_versions.push_back("GLIBCXX_IEEE128_3.4.30");
@@ -247,7 +248,7 @@ check_version(symbol& test, bool added)
test.version_status = symbol::incompatible;
// Check that added symbols are added in the latest pre-release version.
- bool latestp = (test.version_name == "GLIBCXX_3.4.30"
+ bool latestp = (test.version_name == "GLIBCXX_3.4.31"
// XXX remove next line when baselines have been regenerated.
|| test.version_name == "GLIBCXX_IEEE128_3.4.30"
|| test.version_name == "CXXABI_1.3.13"
--- libstdc++-v3/include/bits/basic_string.h.jj 2022-06-17 11:08:11.971491626
+0200
+++ libstdc++-v3/include/bits/basic_string.h 2022-07-26 12:42:38.008440082
+0200
@@ -2504,6 +2504,10 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
_M_replace_aux(size_type __pos1, size_type __n1, size_type __n2,
_CharT __c);
+ __attribute__((__noinline__, __noclone__, __cold__)) void
+ _M_replace_cold(pointer __p, size_type __len1, const _CharT* __s,
+ const size_type __len2, const size_type __how_much);
+
_GLIBCXX20_CONSTEXPR
basic_string&
_M_replace(size_type __pos, size_type __len1, const _CharT* __s,
--- libstdc++-v3/include/bits/basic_string.tcc.jj 2022-06-15
10:43:46.796946222 +0200
+++ libstdc++-v3/include/bits/basic_string.tcc 2022-07-26 13:43:35.293012051
+0200
@@ -471,6 +471,37 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
template<typename _CharT, typename _Traits, typename _Alloc>
+ __attribute__((__noinline__, __noclone__, __cold__)) void
+ basic_string<_CharT, _Traits, _Alloc>::
+ _M_replace_cold(pointer __p, size_type __len1, const _CharT* __s,
+ const size_type __len2, const size_type __how_much)
+ {
+ // Work in-place.
+ if (__len2 && __len2 <= __len1)
+ this->_S_move(__p, __s, __len2);
+ if (__how_much && __len1 != __len2)
+ this->_S_move(__p + __len2, __p + __len1, __how_much);
+ if (__len2 > __len1)
+ {
+ if (__s + __len2 <= __p + __len1)
+ this->_S_move(__p, __s, __len2);
+ else if (__s >= __p + __len1)
+ {
+ // Hint to middle end that __p and __s overlap
+ // (PR 98465).
+ const size_type __poff = (__s - __p) + (__len2 - __len1);
+ this->_S_copy(__p, __p + __poff, __len2);
+ }
+ else
+ {
+ const size_type __nleft = (__p + __len1) - __s;
+ this->_S_move(__p, __s, __nleft);
+ this->_S_copy(__p + __nleft, __p + __len2, __len2 - __nleft);
+ }
+ }
+ }
+
+ template<typename _CharT, typename _Traits, typename _Alloc>
_GLIBCXX20_CONSTEXPR
basic_string<_CharT, _Traits, _Alloc>&
basic_string<_CharT, _Traits, _Alloc>::
@@ -500,7 +531,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
}
else
#endif
- if (_M_disjunct(__s))
+ if (__builtin_expect(_M_disjunct(__s), true))
{
if (__how_much && __len1 != __len2)
this->_S_move(__p + __len2, __p + __len1, __how_much);
@@ -508,32 +539,7 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
this->_S_copy(__p, __s, __len2);
}
else
- {
- // Work in-place.
- if (__len2 && __len2 <= __len1)
- this->_S_move(__p, __s, __len2);
- if (__how_much && __len1 != __len2)
- this->_S_move(__p + __len2, __p + __len1, __how_much);
- if (__len2 > __len1)
- {
- if (__s + __len2 <= __p + __len1)
- this->_S_move(__p, __s, __len2);
- else if (__s >= __p + __len1)
- {
- // Hint to middle end that __p and __s overlap
- // (PR 98465).
- const size_type __poff = (__s - __p) + (__len2 - __len1);
- this->_S_copy(__p, __p + __poff, __len2);
- }
- else
- {
- const size_type __nleft = (__p + __len1) - __s;
- this->_S_move(__p, __s, __nleft);
- this->_S_copy(__p + __nleft, __p + __len2,
- __len2 - __nleft);
- }
- }
- }
+ _M_replace_cold(__p, __len1, __s, __len2, __how_much);
}
else
this->_M_mutate(__pos, __len1, __s, __len2);
@@ -1000,6 +1006,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
// to ensure the definition in libstdc++.so is unique (PR 86138).
extern template basic_string<char>::size_type
basic_string<char>::_Rep::_S_empty_rep_storage[];
+# elif _GLIBCXX_EXTERN_TEMPLATE > 0
+ // Export _M_replace_cold even for C++20.
+ extern template void
+ basic_string<char>::_M_replace_cold(char *, size_type, const char*,
+ const size_type, const size_type);
# endif
extern template
@@ -1021,6 +1032,11 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
# elif ! _GLIBCXX_USE_CXX11_ABI
extern template basic_string<wchar_t>::size_type
basic_string<wchar_t>::_Rep::_S_empty_rep_storage[];
+# elif _GLIBCXX_EXTERN_TEMPLATE > 0
+ // Export _M_replace_cold even for C++20.
+ extern template void
+ basic_string<wchar_t>::_M_replace_cold(wchar_t*, size_type, const wchar_t*,
+ const size_type, const size_type);
# endif
extern template
--- libstdc++-v3/configure.jj 2022-07-26 10:32:24.395262574 +0200
+++ libstdc++-v3/configure 2022-07-26 13:16:09.830330197 +0200
@@ -69048,7 +69048,7 @@ $as_echo "$as_me: WARNING: === Symbol ve
fi
# For libtool versioning info, format is CURRENT:REVISION:AGE
-libtool_VERSION=6:30:0
+libtool_VERSION=6:31:0
# Everything parsed; figure out what files and settings to use.
case $enable_symvers in
Jakub
