libstdc++: Inline all basic_string::compare overloads [PR59048]

Defining the compare member functions inline allows calls to
traits_type::length and std::min to be inlined, taking advantage of
constant expression arguments. When not inline, the compiler prefers to
use the explicit instantiation definitions in libstdc++.so and can't
take advantage of constant arguments.

libstdc++-v3/ChangeLog:

	PR libstdc++/59048
	* include/bits/basic_string.h (compare): Define inline.
	* include/bits/basic_string.tcc (compare): Remove out-of-line
	definitions.
	* include/bits/cow_string.h (compare): Define inline.
	* testsuite/21_strings/basic_string/operations/compare/char/3.cc:
	New test.

3 files changed, 116 insertions, 95 deletions

diff --git a/libstdc++-v3/include/bits/basic_string.h b/libstdc++-v3/include/bits/basic_string.h
index f76ddf970c6..a34b3d9ed28 100644
--- a/libstdc++-v3/include/bits/basic_string.h
+++ b/libstdc++-v3/include/bits/basic_string.h
@@ -3235,7 +3235,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
       */
       _GLIBCXX20_CONSTEXPR
       int
-      compare(size_type __pos, size_type __n, const basic_string& __str) const;
+      compare(size_type __pos, size_type __n, const basic_string& __str) const
+      {
+	_M_check(__pos, "basic_string::compare");
+	__n = _M_limit(__pos, __n);
+	const size_type __osize = __str.size();
+	const size_type __len = std::min(__n, __osize);
+	int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
+	if (!__r)
+	  __r = _S_compare(__n, __osize);
+	return __r;
+      }
 
       /**
        *  @brief  Compare substring to a substring.
@@ -3263,7 +3273,19 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
       _GLIBCXX20_CONSTEXPR
       int
       compare(size_type __pos1, size_type __n1, const basic_string& __str,
-	      size_type __pos2, size_type __n2 = npos) const;
+	      size_type __pos2, size_type __n2 = npos) const
+      {
+	_M_check(__pos1, "basic_string::compare");
+	__str._M_check(__pos2, "basic_string::compare");
+	__n1 = _M_limit(__pos1, __n1);
+	__n2 = __str._M_limit(__pos2, __n2);
+	const size_type __len = std::min(__n1, __n2);
+	int __r = traits_type::compare(_M_data() + __pos1,
+				       __str.data() + __pos2, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __n2);
+	return __r;
+      }
 
       /**
        *  @brief  Compare to a C string.
@@ -3281,7 +3303,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
       */
       _GLIBCXX20_CONSTEXPR
       int
-      compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT;
+      compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT
+      {
+	__glibcxx_requires_string(__s);
+	const size_type __size = this->size();
+	const size_type __osize = traits_type::length(__s);
+	const size_type __len = std::min(__size, __osize);
+	int __r = traits_type::compare(_M_data(), __s, __len);
+	if (!__r)
+	  __r = _S_compare(__size, __osize);
+	return __r;
+      }
 
       // _GLIBCXX_RESOLVE_LIB_DEFECTS
       // 5 String::compare specification questionable
@@ -3306,7 +3338,18 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
       */
       _GLIBCXX20_CONSTEXPR
       int
-      compare(size_type __pos, size_type __n1, const _CharT* __s) const;
+      compare(size_type __pos, size_type __n1, const _CharT* __s) const
+      {
+	__glibcxx_requires_string(__s);
+	_M_check(__pos, "basic_string::compare");
+	__n1 = _M_limit(__pos, __n1);
+	const size_type __osize = traits_type::length(__s);
+	const size_type __len = std::min(__n1, __osize);
+	int __r = traits_type::compare(_M_data() + __pos, __s, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __osize);
+	return __r;
+      }
 
       /**
        *  @brief  Compare substring against a character %array.
@@ -3335,7 +3378,17 @@ _GLIBCXX_BEGIN_NAMESPACE_CXX11
       _GLIBCXX20_CONSTEXPR
       int
       compare(size_type __pos, size_type __n1, const _CharT* __s,
-	      size_type __n2) const;
+	      size_type __n2) const
+      {
+	__glibcxx_requires_string_len(__s, __n2);
+	_M_check(__pos, "basic_string::compare");
+	__n1 = _M_limit(__pos, __n1);
+	const size_type __len = std::min(__n1, __n2);
+	int __r = traits_type::compare(_M_data() + __pos, __s, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __n2);
+	return __r;
+      }
 
 #if __cplusplus >= 202002L
       constexpr bool
diff --git a/libstdc++-v3/include/bits/basic_string.tcc b/libstdc++-v3/include/bits/basic_string.tcc
index 0696b96604c..4563c61429a 100644
--- a/libstdc++-v3/include/bits/basic_string.tcc
+++ b/libstdc++-v3/include/bits/basic_string.tcc
@@ -847,91 +847,6 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       return npos;
     }
 
-  template<typename _CharT, typename _Traits, typename _Alloc>
-    _GLIBCXX_STRING_CONSTEXPR
-    int
-    basic_string<_CharT, _Traits, _Alloc>::
-    compare(size_type __pos, size_type __n, const basic_string& __str) const
-    {
-      _M_check(__pos, "basic_string::compare");
-      __n = _M_limit(__pos, __n);
-      const size_type __osize = __str.size();
-      const size_type __len = std::min(__n, __osize);
-      int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
-      if (!__r)
-	__r = _S_compare(__n, __osize);
-      return __r;
-    }
-
-  template<typename _CharT, typename _Traits, typename _Alloc>
-    _GLIBCXX_STRING_CONSTEXPR
-    int
-    basic_string<_CharT, _Traits, _Alloc>::
-    compare(size_type __pos1, size_type __n1, const basic_string& __str,
-	    size_type __pos2, size_type __n2) const
-    {
-      _M_check(__pos1, "basic_string::compare");
-      __str._M_check(__pos2, "basic_string::compare");
-      __n1 = _M_limit(__pos1, __n1);
-      __n2 = __str._M_limit(__pos2, __n2);
-      const size_type __len = std::min(__n1, __n2);
-      int __r = traits_type::compare(_M_data() + __pos1,
-				     __str.data() + __pos2, __len);
-      if (!__r)
-	__r = _S_compare(__n1, __n2);
-      return __r;
-    }
-
-  template<typename _CharT, typename _Traits, typename _Alloc>
-    _GLIBCXX_STRING_CONSTEXPR
-    int
-    basic_string<_CharT, _Traits, _Alloc>::
-    compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT
-    {
-      __glibcxx_requires_string(__s);
-      const size_type __size = this->size();
-      const size_type __osize = traits_type::length(__s);
-      const size_type __len = std::min(__size, __osize);
-      int __r = traits_type::compare(_M_data(), __s, __len);
-      if (!__r)
-	__r = _S_compare(__size, __osize);
-      return __r;
-    }
-
-  template<typename _CharT, typename _Traits, typename _Alloc>
-    _GLIBCXX_STRING_CONSTEXPR
-    int
-    basic_string <_CharT, _Traits, _Alloc>::
-    compare(size_type __pos, size_type __n1, const _CharT* __s) const
-    {
-      __glibcxx_requires_string(__s);
-      _M_check(__pos, "basic_string::compare");
-      __n1 = _M_limit(__pos, __n1);
-      const size_type __osize = traits_type::length(__s);
-      const size_type __len = std::min(__n1, __osize);
-      int __r = traits_type::compare(_M_data() + __pos, __s, __len);
-      if (!__r)
-	__r = _S_compare(__n1, __osize);
-      return __r;
-    }
-
-  template<typename _CharT, typename _Traits, typename _Alloc>
-    _GLIBCXX_STRING_CONSTEXPR
-    int
-    basic_string <_CharT, _Traits, _Alloc>::
-    compare(size_type __pos, size_type __n1, const _CharT* __s,
-	    size_type __n2) const
-    {
-      __glibcxx_requires_string_len(__s, __n2);
-      _M_check(__pos, "basic_string::compare");
-      __n1 = _M_limit(__pos, __n1);
-      const size_type __len = std::min(__n1, __n2);
-      int __r = traits_type::compare(_M_data() + __pos, __s, __len);
-      if (!__r)
-	__r = _S_compare(__n1, __n2);
-      return __r;
-    }
-
 #undef _GLIBCXX_STRING_CONSTEXPR
 
   // 21.3.7.9 basic_string::getline and operators
diff --git a/libstdc++-v3/include/bits/cow_string.h b/libstdc++-v3/include/bits/cow_string.h
index 7bceb06a79b..f16e33ac1ef 100644
--- a/libstdc++-v3/include/bits/cow_string.h
+++ b/libstdc++-v3/include/bits/cow_string.h
@@ -2852,7 +2852,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        *  the shorter one is ordered first.
       */
       int
-      compare(size_type __pos, size_type __n, const basic_string& __str) const;
+      compare(size_type __pos, size_type __n, const basic_string& __str) const
+      {
+	_M_check(__pos, "basic_string::compare");
+	__n = _M_limit(__pos, __n);
+	const size_type __osize = __str.size();
+	const size_type __len = std::min(__n, __osize);
+	int __r = traits_type::compare(_M_data() + __pos, __str.data(), __len);
+	if (!__r)
+	  __r = _S_compare(__n, __osize);
+	return __r;
+      }
 
       /**
        *  @brief  Compare substring to a substring.
@@ -2879,7 +2889,19 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       */
       int
       compare(size_type __pos1, size_type __n1, const basic_string& __str,
-	      size_type __pos2, size_type __n2 = npos) const;
+	      size_type __pos2, size_type __n2 = npos) const
+      {
+	_M_check(__pos1, "basic_string::compare");
+	__str._M_check(__pos2, "basic_string::compare");
+	__n1 = _M_limit(__pos1, __n1);
+	__n2 = __str._M_limit(__pos2, __n2);
+	const size_type __len = std::min(__n1, __n2);
+	int __r = traits_type::compare(_M_data() + __pos1,
+				       __str.data() + __pos2, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __n2);
+	return __r;
+      }
 
       /**
        *  @brief  Compare to a C string.
@@ -2896,7 +2918,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        *  ordered first.
       */
       int
-      compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT;
+      compare(const _CharT* __s) const _GLIBCXX_NOEXCEPT
+      {
+	__glibcxx_requires_string(__s);
+	const size_type __size = this->size();
+	const size_type __osize = traits_type::length(__s);
+	const size_type __len = std::min(__size, __osize);
+	int __r = traits_type::compare(_M_data(), __s, __len);
+	if (!__r)
+	  __r = _S_compare(__size, __osize);
+	return __r;
+      }
 
       // _GLIBCXX_RESOLVE_LIB_DEFECTS
       // 5 String::compare specification questionable
@@ -2920,7 +2952,18 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
        *  one is ordered first.
       */
       int
-      compare(size_type __pos, size_type __n1, const _CharT* __s) const;
+      compare(size_type __pos, size_type __n1, const _CharT* __s) const
+      {
+	__glibcxx_requires_string(__s);
+	_M_check(__pos, "basic_string::compare");
+	__n1 = _M_limit(__pos, __n1);
+	const size_type __osize = traits_type::length(__s);
+	const size_type __len = std::min(__n1, __osize);
+	int __r = traits_type::compare(_M_data() + __pos, __s, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __osize);
+	return __r;
+      }
 
       /**
        *  @brief  Compare substring against a character %array.
@@ -2948,7 +2991,17 @@ _GLIBCXX_BEGIN_NAMESPACE_VERSION
       */
       int
       compare(size_type __pos, size_type __n1, const _CharT* __s,
-	      size_type __n2) const;
+	      size_type __n2) const
+      {
+	__glibcxx_requires_string_len(__s, __n2);
+	_M_check(__pos, "basic_string::compare");
+	__n1 = _M_limit(__pos, __n1);
+	const size_type __len = std::min(__n1, __n2);
+	int __r = traits_type::compare(_M_data() + __pos, __s, __len);
+	if (!__r)
+	  __r = _S_compare(__n1, __n2);
+	return __r;
+      }
 
 #if __cplusplus > 201703L
       bool