...one of the most highly
regarded and expertly designed C++ library projects in the
world.
— Herb Sutter and Andrei
Alexandrescu, C++
Coding Standards
Boost.Coroutine supports usage of a segmented-stack, e. g. the size of the stack grows on demand. The coroutine is created with a minimal stack size and will be increased as required. Class segmented_stack_allocator models the stack-allocator concept. In contrast to protected_stack_allocator and standard_stack_allocator it creates a stack which grows on demand.
Note | |
---|---|
Segmented stacks are currently only supported by gcc from version 4.7 and clang from version 3.4 onwards. In order to use a segmented-stack Boost.Coroutine must be built with toolset=gcc segmented-stacks=on at b2/bjam command-line. Applications must be compiled with compiler-flags -fsplit-stack -DBOOST_USE_SEGMENTED_STACKS. |
#include <boost/coroutine/segmented_stack_allocator.hpp> template< typename traitsT > struct basic_segmented_stack_allocator { typedef traitT traits_type; void allocate( stack_context &, std::size_t size); void deallocate( stack_context &); } typedef basic_segmented_stack_allocator< stack_traits > segmented_stack_allocator;
void allocate( stack_context
& sctx, std::size_t size)
traits_type::minimum_size()
<= size
and ! traits_type::is_unbounded() &&
( traits_type::maximum_size() >= size)
.
Allocates memory of at least size
bytes and stores a pointer to the stack and its actual size in sctx
. Depending on the architecture
(the stack grows downwards/upwards) the stored address is the highest/lowest
address of the stack.
void deallocate( stack_context
& sctx)
sctx.sp
is valid, traits_type::minimum_size() <= sctx.size
and !
traits_type::is_unbounded()
&& (
traits_type::maximum_size()
>= sctx.size)
.
Deallocates the stack space.