diff mbox

Container debug light mode

Message ID 5762FDF0.1020308@gmail.com
State New
Headers show

Commit Message

François Dumont June 16, 2016, 7:28 p.m. UTC 
And here is the patch to only add light debug checks to vector and deque.

     * include/debug/debug.h
     (__glibcxx_requires_non_empty_range, __glibcxx_requires_nonempty)
     (__glibcxx_requires_subscript): Move...
     * include/debug/assertions.h: ...here and add __builtin_expect.
     (_GLIBCXX_DEBUG_ONLY): Remove ; value.
     * include/bits/stl_deque.h
     (std::deque<>::operator[]): Add __glibcxx_requires_subscript check.
     (std::deque<>::front()): Add __glibcxx_requires_nonempty check.
     (std::deque<>::back()): Likewise.
     (std::deque<>::pop_front()): Likewise.
     (std::deque<>::pop_back()): Likewise.
     (std::deque<>::swap(deque&)): Add allocator check.
     * include/bits/stl_vector.h
     (std::vector<>::operator[]): Add __glibcxx_requires_subscript check.
     (std::vector<>::front()): Add __glibcxx_requires_nonempty check.
     (std::vector<>::back()): Likewise.
     (std::vector<>::pop_back()): Likewise.
     (std::vector<>::swap(vector&)): Add allocator check.

Tested under Linux x86_64.

François

On 13/06/2016 12:21, Jonathan Wakely wrote:
> On 08/06/16 22:53 +0200, François Dumont wrote:
>> Hi
>>
>>    Here is the patch I already proposed to introduce the debug light 
>> mode for vector and deque containers.
>>
>>    It also simplify some internal calls.
>
> This looks great, and I'd like to see it on trunk, but could you split
> it into two patches please? The simplifications to use
> __iterator_category and replace insert() with _M_insert_* are good but
> are unrelated to the debug mode parts so if there are two separate
> commits it's easier to backport one piece separately, or to identify
> any regressions that might be introduced.
>
>

Comments

Jonathan Wakely June 16, 2016, 8:19 p.m. UTC | #1 
On 16/06/16 21:28 +0200, François Dumont wrote:
>And here is the patch to only add light debug checks to vector and deque.

Excellent, thanks - this is OK for trunk.
diff mbox

Patch

diff --git a/libstdc++-v3/include/bits/stl_deque.h b/libstdc++-v3/include/bits/stl_deque.h
index f63ae4c..66b8da6 100644
--- a/libstdc++-v3/include/bits/stl_deque.h
+++ b/libstdc++-v3/include/bits/stl_deque.h
@@ -63,6 +63,8 @@ 
 #include <initializer_list>
 #endif
 
+#include <debug/assertions.h>
+
 namespace std _GLIBCXX_VISIBILITY(default)
 {
 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
@@ -1365,7 +1367,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       reference
       operator[](size_type __n) _GLIBCXX_NOEXCEPT
-      { return this->_M_impl._M_start[difference_type(__n)]; }
+      {
+	__glibcxx_requires_subscript(__n);
+	return this->_M_impl._M_start[difference_type(__n)];
+      }
 
       /**
        *  @brief Subscript access to the data contained in the %deque.
@@ -1380,7 +1385,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       const_reference
       operator[](size_type __n) const _GLIBCXX_NOEXCEPT
-      { return this->_M_impl._M_start[difference_type(__n)]; }
+      {
+	__glibcxx_requires_subscript(__n);
+	return this->_M_impl._M_start[difference_type(__n)];
+      }
 
     protected:
       /// Safety check used only from at().
@@ -1437,7 +1445,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       reference
       front() _GLIBCXX_NOEXCEPT
-      { return *begin(); }
+      {
+	__glibcxx_requires_nonempty();
+	return *begin();
+      }
 
       /**
        *  Returns a read-only (constant) reference to the data at the first
@@ -1445,7 +1456,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       const_reference
       front() const _GLIBCXX_NOEXCEPT
-      { return *begin(); }
+      {
+	__glibcxx_requires_nonempty();
+	return *begin();
+      }
 
       /**
        *  Returns a read/write reference to the data at the last element of the
@@ -1454,6 +1468,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       reference
       back() _GLIBCXX_NOEXCEPT
       {
+	__glibcxx_requires_nonempty();
 	iterator __tmp = end();
 	--__tmp;
 	return *__tmp;
@@ -1466,6 +1481,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       const_reference
       back() const _GLIBCXX_NOEXCEPT
       {
+	__glibcxx_requires_nonempty();
 	const_iterator __tmp = end();
 	--__tmp;
 	return *__tmp;
@@ -1549,6 +1565,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       void
       pop_front() _GLIBCXX_NOEXCEPT
       {
+	__glibcxx_requires_nonempty();
 	if (this->_M_impl._M_start._M_cur
 	    != this->_M_impl._M_start._M_last - 1)
 	  {
@@ -1571,6 +1588,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       void
       pop_back() _GLIBCXX_NOEXCEPT
       {
+	__glibcxx_requires_nonempty();
 	if (this->_M_impl._M_finish._M_cur
 	    != this->_M_impl._M_finish._M_first)
 	  {
@@ -1789,6 +1807,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       void
       swap(deque& __x) _GLIBCXX_NOEXCEPT
       {
+#if __cplusplus >= 201103L
+	__glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value
+			 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator());
+#endif
 	_M_impl._M_swap_data(__x._M_impl);
 	_Alloc_traits::_S_on_swap(_M_get_Tp_allocator(),
 				  __x._M_get_Tp_allocator());
diff --git a/libstdc++-v3/include/bits/stl_vector.h b/libstdc++-v3/include/bits/stl_vector.h
index 8badea3..e2c42cb 100644
--- a/libstdc++-v3/include/bits/stl_vector.h
+++ b/libstdc++-v3/include/bits/stl_vector.h
@@ -63,6 +63,8 @@ 
 #include <initializer_list>
 #endif
 
+#include <debug/assertions.h>
+
 namespace std _GLIBCXX_VISIBILITY(default)
 {
 _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
@@ -784,7 +786,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       reference
       operator[](size_type __n) _GLIBCXX_NOEXCEPT
-      { return *(this->_M_impl._M_start + __n); }
+      {
+	__glibcxx_requires_subscript(__n);
+	return *(this->_M_impl._M_start + __n);
+      }
 
       /**
        *  @brief  Subscript access to the data contained in the %vector.
@@ -799,7 +804,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       const_reference
       operator[](size_type __n) const _GLIBCXX_NOEXCEPT
-      { return *(this->_M_impl._M_start + __n); }
+      {
+	__glibcxx_requires_subscript(__n);
+	return *(this->_M_impl._M_start + __n);
+      }
 
     protected:
       /// Safety check used only from at().
@@ -856,7 +864,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       reference
       front() _GLIBCXX_NOEXCEPT
-      { return *begin(); }
+      {
+	__glibcxx_requires_nonempty();
+	return *begin();
+      }
 
       /**
        *  Returns a read-only (constant) reference to the data at the first
@@ -864,7 +875,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       const_reference
       front() const _GLIBCXX_NOEXCEPT
-      { return *begin(); }
+      {
+	__glibcxx_requires_nonempty();
+	return *begin();
+      }
 
       /**
        *  Returns a read/write reference to the data at the last
@@ -872,7 +886,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       reference
       back() _GLIBCXX_NOEXCEPT
-      { return *(end() - 1); }
+      {
+	__glibcxx_requires_nonempty();
+	return *(end() - 1);
+      }
       
       /**
        *  Returns a read-only (constant) reference to the data at the
@@ -880,7 +897,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
        */
       const_reference
       back() const _GLIBCXX_NOEXCEPT
-      { return *(end() - 1); }
+      {
+	__glibcxx_requires_nonempty();
+	return *(end() - 1);
+      }
 
       // _GLIBCXX_RESOLVE_LIB_DEFECTS
       // DR 464. Suggestion for new member functions in standard containers.
@@ -955,6 +975,7 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       void
       pop_back() _GLIBCXX_NOEXCEPT
       {
+	__glibcxx_requires_nonempty();
 	--this->_M_impl._M_finish;
 	_Alloc_traits::destroy(this->_M_impl, this->_M_impl._M_finish);
       }
@@ -1205,6 +1226,10 @@  _GLIBCXX_BEGIN_NAMESPACE_CONTAINER
       void
       swap(vector& __x) _GLIBCXX_NOEXCEPT
       {
+#if __cplusplus >= 201103L
+	__glibcxx_assert(_Alloc_traits::propagate_on_container_swap::value
+			 || _M_get_Tp_allocator() == __x._M_get_Tp_allocator());
+#endif
 	this->_M_impl._M_swap_data(__x._M_impl);
 	_Alloc_traits::_S_on_swap(_M_get_Tp_allocator(),
 				  __x._M_get_Tp_allocator());
diff --git a/libstdc++-v3/include/debug/assertions.h b/libstdc++-v3/include/debug/assertions.h
index 802645c..3708d12 100644
--- a/libstdc++-v3/include/debug/assertions.h
+++ b/libstdc++-v3/include/debug/assertions.h
@@ -33,20 +33,36 @@ 
 
 # define _GLIBCXX_DEBUG_ASSERT(_Condition)
 # define _GLIBCXX_DEBUG_PEDASSERT(_Condition)
-# define _GLIBCXX_DEBUG_ONLY(_Statement) ;
+# define _GLIBCXX_DEBUG_ONLY(_Statement)
 
-#else
-
-#define _GLIBCXX_DEBUG_ASSERT(_Condition) __glibcxx_assert(_Condition)
+#endif
 
-#ifdef _GLIBCXX_DEBUG_PEDANTIC
-# define _GLIBCXX_DEBUG_PEDASSERT(_Condition) _GLIBCXX_DEBUG_ASSERT(_Condition)
+#ifndef _GLIBCXX_ASSERTIONS
+# define __glibcxx_requires_non_empty_range(_First,_Last)
+# define __glibcxx_requires_nonempty()
+# define __glibcxx_requires_subscript(_N)
 #else
-# define _GLIBCXX_DEBUG_PEDASSERT(_Condition)
+
+// Verify that [_First, _Last) forms a non-empty iterator range.
+# define __glibcxx_requires_non_empty_range(_First,_Last)	\
+  __glibcxx_assert(__builtin_expect(_First != _Last, true))
+# define __glibcxx_requires_subscript(_N)	\
+  __glibcxx_assert(__builtin_expect(_N < this->size(), true))
+// Verify that the container is nonempty
+# define __glibcxx_requires_nonempty()		\
+  __glibcxx_assert(__builtin_expect(!this->empty(), true))
 #endif
 
-# define _GLIBCXX_DEBUG_ONLY(_Statement) _Statement
+#ifdef _GLIBCXX_DEBUG
+# define _GLIBCXX_DEBUG_ASSERT(_Condition) __glibcxx_assert(_Condition)
 
+# ifdef _GLIBCXX_DEBUG_PEDANTIC
+#  define _GLIBCXX_DEBUG_PEDASSERT(_Condition) _GLIBCXX_DEBUG_ASSERT(_Condition)
+# else
+#  define _GLIBCXX_DEBUG_PEDASSERT(_Condition)
+# endif
+
+# define _GLIBCXX_DEBUG_ONLY(_Statement) _Statement
 #endif
 
 #endif // _GLIBCXX_DEBUG_ASSERTIONS
diff --git a/libstdc++-v3/include/debug/debug.h b/libstdc++-v3/include/debug/debug.h
index 3d46b6d..79fe00d 100644
--- a/libstdc++-v3/include/debug/debug.h
+++ b/libstdc++-v3/include/debug/debug.h
@@ -74,24 +74,11 @@  namespace __gnu_debug
 # define __glibcxx_requires_heap_pred(_First,_Last,_Pred)
 # define __glibcxx_requires_string(_String)
 # define __glibcxx_requires_string_len(_String,_Len)
-# define __glibcxx_requires_subscript(_N)
 # define __glibcxx_requires_irreflexive(_First,_Last)
 # define __glibcxx_requires_irreflexive2(_First,_Last)
 # define __glibcxx_requires_irreflexive_pred(_First,_Last,_Pred)
 # define __glibcxx_requires_irreflexive_pred2(_First,_Last,_Pred)
 
-#ifdef _GLIBCXX_ASSERTIONS
-// Verify that [_First, _Last) forms a non-empty iterator range.
-# define __glibcxx_requires_non_empty_range(_First,_Last) \
-  __glibcxx_assert(_First != _Last)
-// Verify that the container is nonempty
-# define __glibcxx_requires_nonempty() \
-  __glibcxx_assert(! this->empty())
-#else
-# define __glibcxx_requires_non_empty_range(_First,_Last)
-# define __glibcxx_requires_nonempty()
-#endif
-
 #else
 
 # include <debug/macros.h>
@@ -99,8 +86,6 @@  namespace __gnu_debug
 # define __glibcxx_requires_cond(_Cond,_Msg) _GLIBCXX_DEBUG_VERIFY(_Cond,_Msg)
 # define __glibcxx_requires_valid_range(_First,_Last)	\
   __glibcxx_check_valid_range(_First,_Last)
-# define __glibcxx_requires_non_empty_range(_First,_Last)	\
-  __glibcxx_check_non_empty_range(_First,_Last)
 # define __glibcxx_requires_sorted(_First,_Last)	\
   __glibcxx_check_sorted(_First,_Last)
 # define __glibcxx_requires_sorted_pred(_First,_Last,_Pred)	\
@@ -121,11 +106,9 @@  namespace __gnu_debug
   __glibcxx_check_heap(_First,_Last)
 # define __glibcxx_requires_heap_pred(_First,_Last,_Pred)	\
   __glibcxx_check_heap_pred(_First,_Last,_Pred)
-# define __glibcxx_requires_nonempty() __glibcxx_check_nonempty()
 # define __glibcxx_requires_string(_String) __glibcxx_check_string(_String)
 # define __glibcxx_requires_string_len(_String,_Len)	\
   __glibcxx_check_string_len(_String,_Len)
-# define __glibcxx_requires_subscript(_N) __glibcxx_check_subscript(_N)
 # define __glibcxx_requires_irreflexive(_First,_Last)	\
   __glibcxx_check_irreflexive(_First,_Last)
 # define __glibcxx_requires_irreflexive2(_First,_Last)	\
diff --git a/libstdc++-v3/include/debug/helper_functions.h b/libstdc++-v3/include/debug/helper_functions.h
index 5ee33e8..f1a74eb 100644
--- a/libstdc++-v3/include/debug/helper_functions.h
+++ b/libstdc++-v3/include/debug/helper_functions.h
@@ -138,6 +138,7 @@  namespace __gnu_debug
 	  return __dist.first >= 0;
 	}
 
+      // Can't tell so assume it is fine.
       return true;
     }