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26 <div class=
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27 <a name=
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"Stack allocation">Stack allocation
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28 </h2></div></div></div>
30 <dt><span class=
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"stack/protected_fixedsize.html">Class
<span class=
"emphasis"><em>protected_fixedsize
</em></span></a></span></dt>
31 <dt><span class=
"section"><a href=
"stack/pooled_fixedsize.html">Class
<span class=
"emphasis"><em>pooled_fixedsize_stack
</em></span></a></span></dt>
32 <dt><span class=
"section"><a href=
"stack/fixedsize.html">Class
<span class=
"emphasis"><em>fixedsize_stack
</em></span></a></span></dt>
33 <dt><span class=
"section"><a href=
"stack/segmented.html">Class
<span class=
"emphasis"><em>segmented_stack
</em></span></a></span></dt>
34 <dt><span class=
"section"><a href=
"stack/stack_traits.html">Class
<span class=
"emphasis"><em>stack_traits
</em></span></a></span></dt>
35 <dt><span class=
"section"><a href=
"stack/stack_context.html">Class
<span class=
"emphasis"><em>stack_context
</em></span></a></span></dt>
36 <dt><span class=
"section"><a href=
"stack/valgrind.html">Support for valgrind
</a></span></dt>
39 The memory used by the stack is allocated/deallocated via a
<span class=
"emphasis"><em>StackAllocator
</em></span>
40 which is required to model a
<span class=
"emphasis"><em>stack-allocator concept
</em></span>.
43 <a name=
"context.stack.h0"></a>
44 <span><a name=
"context.stack._emphasis_stack_allocator_concept__emphasis_"></a></span><a class=
"link" href=
"stack.html#context.stack._emphasis_stack_allocator_concept__emphasis_"><span class=
"emphasis"><em>stack-allocator
45 concept
</em></span></a>
48 A
<span class=
"emphasis"><em>StackAllocator
</em></span> must satisfy the
<span class=
"emphasis"><em>stack-allocator
49 concept
</em></span> requirements shown in the following table, in which
<code class=
"computeroutput"><span class=
"identifier">a
</span></code> is an object of a
<span class=
"emphasis"><em>StackAllocator
</em></span>
50 type,
<code class=
"computeroutput"><span class=
"identifier">sctx
</span></code> is a
<code class=
"computeroutput"><span class=
"identifier">stack_context
</span></code>, and
<code class=
"computeroutput"><span class=
"identifier">size
</span></code>
51 is a
<code class=
"computeroutput"><span class=
"identifier">std
</span><span class=
"special">::
</span><span class=
"identifier">size_t
</span></code>:
53 <div class=
"informaltable"><table class=
"table">
80 <code class=
"computeroutput"><span class=
"identifier">a
</span><span class=
"special">(
</span><span class=
"identifier">size
</span><span class=
"special">)
</span></code>
87 creates a stack allocator
94 <code class=
"computeroutput"><span class=
"identifier">a
</span><span class=
"special">.
</span><span class=
"identifier">allocate
</span><span class=
"special">()
</span></code>
99 <code class=
"computeroutput"><span class=
"identifier">stack_context
</span></code>
111 <code class=
"computeroutput"><span class=
"identifier">a
</span><span class=
"special">.
</span><span class=
"identifier">deallocate
</span><span class=
"special">(
</span>
112 <span class=
"identifier">sctx
</span><span class=
"special">)
</span></code>
117 <code class=
"computeroutput"><span class=
"keyword">void
</span></code>
122 deallocates the stack created by
<code class=
"computeroutput"><span class=
"identifier">a
</span><span class=
"special">.
</span><span class=
"identifier">allocate
</span><span class=
"special">()
</span></code>
128 <div class=
"important"><table border=
"0" summary=
"Important">
130 <td rowspan=
"2" align=
"center" valign=
"top" width=
"25"><img alt=
"[Important]" src=
"../../../../../doc/src/images/important.png"></td>
131 <th align=
"left">Important
</th>
133 <tr><td align=
"left" valign=
"top"><p>
134 The implementation of
<code class=
"computeroutput"><span class=
"identifier">allocate
</span><span class=
"special">()
</span></code> might include logic to protect against
135 exceeding the context's available stack size rather than leaving it as undefined
139 <div class=
"important"><table border=
"0" summary=
"Important">
141 <td rowspan=
"2" align=
"center" valign=
"top" width=
"25"><img alt=
"[Important]" src=
"../../../../../doc/src/images/important.png"></td>
142 <th align=
"left">Important
</th>
144 <tr><td align=
"left" valign=
"top"><p>
145 Calling
<code class=
"computeroutput"><span class=
"identifier">deallocate
</span><span class=
"special">()
</span></code>
146 with a
<code class=
"computeroutput"><span class=
"identifier">stack_context
</span></code> not
147 set by
<code class=
"computeroutput"><span class=
"identifier">allocate
</span><span class=
"special">()
</span></code>
148 results in undefined behaviour.
151 <div class=
"note"><table border=
"0" summary=
"Note">
153 <td rowspan=
"2" align=
"center" valign=
"top" width=
"25"><img alt=
"[Note]" src=
"../../../../../doc/src/images/note.png"></td>
154 <th align=
"left">Note
</th>
156 <tr><td align=
"left" valign=
"top"><p>
157 The stack is not required to be aligned; alignment takes place inside
<span class=
"emphasis"><em>execution_context
</em></span>.
160 <div class=
"note"><table border=
"0" summary=
"Note">
162 <td rowspan=
"2" align=
"center" valign=
"top" width=
"25"><img alt=
"[Note]" src=
"../../../../../doc/src/images/note.png"></td>
163 <th align=
"left">Note
</th>
165 <tr><td align=
"left" valign=
"top"><p>
166 Depending on the architecture
<code class=
"computeroutput"><span class=
"identifier">allocate
</span><span class=
"special">()
</span></code> stores an address from the top of the stack
167 (growing downwards) or the bottom of the stack (growing upwards).
171 <table xmlns:
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172 <td align=
"left"></td>
173 <td align=
"right"><div class=
"copyright-footer">Copyright
© 2014 Oliver Kowalke
<p>
174 Distributed under the Boost Software License, Version
1.0. (See accompanying
175 file LICENSE_1_0.txt or copy at
<a href=
"http://www.boost.org/LICENSE_1_0.txt" target=
"_top">http://www.boost.org/LICENSE_1_0.txt
</a>)
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