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+                      rbb7c77d
 More operating system support is required to make this model viable, but there is still the serially-reusable problem with user-level threading.
 Leaving the 1:1 model with no atomic actions along the fastpath and no special operating-system support required.
 The 1:1 model still has the serially-reusable problem with user-level threading, which is addressed in \VRef{}, and the greatest potential for heap blowup for certain allocation patterns.
+The 1:1 model still has the serially-reusable problem with user-level threading, which is addressed in \VRef{s:UserlevelThreadingSupport}, and the greatest potential for heap blowup for certain allocation patterns.
 …
 To obtain $O(1)$ external latency means obtaining one large storage area from the operating system and subdividing it across all program allocations, which requires a good guess at the program storage high-watermark and potential large external fragmentation.
 Excluding real-time operating-systems, operating-system operations are unbounded, and hence some external latency is unavoidable.
 The mitigating factor is that operating-system calls can often be reduced if a programmer has a sense of the storage high-watermark and the allocator is capable of using this information (see @malloc_expansion@ \VRef{}).
+The mitigating factor is that operating-system calls can often be reduced if a programmer has a sense of the storage high-watermark and the allocator is capable of using this information (see @malloc_expansion@ \VPageref{p:malloc_expansion}).
 Furthermore, while operating-system calls are unbounded, many are now reasonably fast, so their latency is tolerable and infrequent.
 …
 \section{Statistics and Debugging Modes}
+\section{Statistics and Debugging}
 llheap can be built to accumulate fast and largely contention-free allocation statistics to help understand allocation behaviour.
 …
 There is an unfortunate problem in detecting unfreed storage because some library routines assume their allocations have life-time duration, and hence, do not free their storage.
 For example, @printf@ allocates a 1024 buffer on first call and never deletes this buffer.
 To prevent a false positive for unfreed storage, it is possible to specify an amount of storage that is never freed (see \VRef{}), and it is subtracted from the total allocate/free difference.
+To prevent a false positive for unfreed storage, it is possible to specify an amount of storage that is never freed (see @malloc_unfreed@ \VPageref{p:malloc_unfreed}), and it is subtracted from the total allocate/free difference.
 Determining the amount of never-freed storage is annoying, but once done, any warnings of unfreed storage are application related.
 …
 \section{User-level Threading Support}
+\label{s:UserlevelThreadingSupport}
 The serially-reusable problem (see \VRef{s:AllocationFastpath}) occurs for kernel threads in the ``T:H model, H = number of CPUs'' model and for user threads in the ``1:1'' model, where llheap uses the ``1:1'' model.
 …
 It is possible to zero fill or align an allocation but not both.
 \item
 It is \emph{only} possible to zero fill and array allocation.
+It is \emph{only} possible to zero fill an array allocation.
 \item
 It is not possible to resize a memory allocation without data copying.
 …
 void free( void * ptr );
 void * memalign( size_t alignment, size_t size );
+void * aligned_alloc( size_t alignment, size_t size );
+int posix_memalign( void ** memptr, size_t alignment, size_t size );
 void * valloc( size_t size );
 void * pvalloc( size_t size );
 struct mallinfo mallinfo( void );
 int mallopt( int param, int val );
 …
 Most allocators use @nullptr@ to indicate an allocation failure, specifically out of memory;
 hence the need to return an alternate value for a zero-sized allocation.
+The alternative is to abort a program when out of memory.
+In theory, notifying the programmer allows recovery;
+in practice, it is almost impossible to gracefully recover when out of memory, so the cheaper approach of returning @nullptr@ for a zero-sized allocation is chosen for llheap.
+A different approach allowed by the C API is to abort a program when out of memory and return @nullptr@ for a zero-sized allocation.
+In theory, notifying the programmer of memory failure allows recovery;
+in practice, it is almost impossible to gracefully recover when out of memory.
+Hence, the cheaper approach of returning @nullptr@ for a zero-sized allocation is chosen because no pseudo allocation is necessary.
 \subsection{C Interface}
+Within the C type-system, it is still possible to increase orthogonality and functionality of the dynamic-memory API to make the allocator more usable for programmers.
+For C, it is possible to increase functionality and orthogonality of the dynamic-memory API to make allocation better for programmers.
+For existing C allocation routines:
+\begin{itemize}
+\item
+@calloc@ sets the sticky zero-fill property.
+\item
+@memalign@, @aligned_alloc@, @posix_memalign@, @valloc@ and @pvalloc@ set the sticky alignment property.
+\item
+@realloc@ and @reallocarray@ preserve sticky properties.
+\end{itemize}
+The C dynamic-memory API is extended with the following routines:
 \paragraph{\lstinline{void * aalloc( size_t dim, size_t elemSize )}}
 @aalloc@ is an extension of malloc.
 It allows programmer to allocate a dynamic array of objects without calculating the total size of array explicitly.
+The only alternate of this routine in the other allocators is @calloc@ but @calloc@ also fills the dynamic memory with 0 which makes it slower for a programmer who only wants to dynamically allocate an array of objects without filling it with 0.
 \paragraph{Usage}
+extends @calloc@ for allocating a dynamic array of objects without calculating the total size of array explicitly but \emph{without} zero-filling the memory.
+@aalloc@ is significantly faster than @calloc@, which is the only alternative.
+\noindent\textbf{Usage}
 @aalloc@ takes two parameters.
+\begin{itemize}
+\item
+@dim@: number of objects in the array
+\item
+@elemSize@: size of the object in the array.
+\end{itemize}
+It returns address of dynamic object allocated on heap that can contain dim number of objects of the size elemSize.
+On failure, it returns a @NULL@ pointer.
+\begin{itemize}
+\item
+@dim@: number of array objects
+\item
+@elemSize@: size of array object
+\end{itemize}
+It returns the address of the dynamic array or @NULL@ if either @dim@ or @elemSize@ are zero.
 \paragraph{\lstinline{void * resize( void * oaddr, size_t size )}}
 @resize@ is an extension of relloc.
 It allows programmer to reuse a currently allocated dynamic object with a new size requirement.
+Its alternate in the other allocators is @realloc@ but relloc also copy the data in old object to the new object which makes it slower for the programmer who only wants to reuse an old dynamic object for a new size requirement but does not want to preserve the data in the old object to the new object.
 \paragraph{Usage}
+extends @realloc@ for resizing an existing allocation \emph{without} copying previous data into the new allocation or preserving sticky properties.
+@resize@ is significantly faster than @realloc@, which is the only alternative.
+\noindent\textbf{Usage}
 @resize@ takes two parameters.
+\begin{itemize}
+\item
+@oaddr@: the address of the old object that needs to be resized.
+\item
+@size@: the new size requirement of the to which the old object needs to be resized.
+\end{itemize}
+It returns an object that is of the size given but it does not preserve the data in the old object.
+On failure, it returns a @NULL@ pointer.
+\begin{itemize}
+\item
+@oaddr@: address to be resized
+\item
+@size@: new allocation size (smaller or larger than previous)
+\end{itemize}
+It returns the address of the old or new storage with the specified new size or @NULL@ if @size@ is zero.
+\paragraph{\lstinline{void * amemalign( size_t alignment, size_t dim, size_t elemSize )}}
+extends @aalloc@ and @memalign@ for allocating an aligned dynamic array of objects.
+Sets sticky alignment property.
+\noindent\textbf{Usage}
+@amemalign@ takes three parameters.
+\begin{itemize}
+\item
+@alignment@: alignment requirement
+\item
+@dim@: number of array objects
+\item
+@elemSize@: size of array object
+\end{itemize}
+It returns the address of the aligned dynamic-array or @NULL@ if either @dim@ or @elemSize@ are zero.
+\paragraph{\lstinline{void * cmemalign( size_t alignment, size_t dim, size_t elemSize )}}
+extends @amemalign@ with zero fill and has the same usage as @amemalign@.
+Sets sticky zero-fill and alignment property.
+It returns the address of the aligned, zero-filled dynamic-array or @NULL@ if either @dim@ or @elemSize@ are zero.
+\paragraph{\lstinline{size_t malloc_alignment( void * addr )}}
+returns the alignment of the dynamic object for use in aligning similar allocations.
+\noindent\textbf{Usage}
+@malloc_alignment@ takes one parameter.
+\begin{itemize}
+\item
+@addr@: address of an allocated object.
+\end{itemize}
+It returns the alignment of the given object, where objects not allocated with alignment return the minimal allocation alignment.
+\paragraph{\lstinline{bool malloc_zero_fill( void * addr )}}
+returns true if the object has the zero-fill sticky property for use in zero filling similar allocations.
+\noindent\textbf{Usage}
+@malloc_zero_fill@ takes one parameters.
+\begin{itemize}
+\item
+@addr@: address of an allocated object.
+\end{itemize}
+It returns true if the zero-fill sticky property is set and false otherwise.
+\paragraph{\lstinline{size_t malloc_size( void * addr )}}
+returns the request size of the dynamic object (updated when an object is resized) for use in similar allocations.
+See also @malloc_usable_size@.
+\noindent\textbf{Usage}
+@malloc_size@ takes one parameters.
+\begin{itemize}
+\item
+@addr@: address of an allocated object.
+\end{itemize}
+It returns the request size or zero if @addr@ is @NULL@.
+\paragraph{\lstinline{int malloc_stats_fd( int fd )}}
+changes the file descriptor where @malloc_stats@ writes statistics (default @stdout@).
+\noindent\textbf{Usage}
+@malloc_stats_fd@ takes one parameters.
+\begin{itemize}
+\item
+@fd@: files description.
+\end{itemize}
+It returns the previous file descriptor.
+\paragraph{\lstinline{size_t malloc_expansion()}}
+\label{p:malloc_expansion}
+set the amount (bytes) to extend the heap when there is insufficient free storage to service an allocation request.
+It returns the heap extension size used throughout a program, \ie called once at heap initialization.
+\paragraph{\lstinline{size_t malloc_mmap_start()}}
+set the crossover between allocations occurring in the @sbrk@ area or separately mapped.
+It returns the crossover point used throughout a program, \ie called once at heap initialization.
+\paragraph{\lstinline{size_t malloc_unfreed()}}
+\label{p:malloc_unfreed}
+amount subtracted to adjust for unfreed program storage (debug only).
+It returns the new subtraction amount and called by @malloc_stats@.
+\subsection{\CC Interface}
+The following extensions take advantage of overload polymorphism in the \CC type-system.
 \paragraph{\lstinline{void * resize( void * oaddr, size_t nalign, size_t size )}}
+This @resize@ is an extension of the above @resize@ (FIX ME: cite above resize).
+In addition to resizing the size of of an old object, it can also realign the old object to a new alignment requirement.
+\paragraph{Usage}
+This resize takes three parameters.
+It takes an additional parameter of nalign as compared to the above resize (FIX ME: cite above resize).
+\begin{itemize}
+\item
+@oaddr@: the address of the old object that needs to be resized.
+\item
+@nalign@: the new alignment to which the old object needs to be realigned.
+\item
+@size@: the new size requirement of the to which the old object needs to be resized.
+\end{itemize}
+It returns an object with the size and alignment given in the parameters.
+On failure, it returns a @NULL@ pointer.
+\paragraph{\lstinline{void * amemalign( size_t alignment, size_t dim, size_t elemSize )}}
+amemalign is a hybrid of memalign and aalloc.
+It allows programmer to allocate an aligned dynamic array of objects without calculating the total size of the array explicitly.
+It frees the programmer from calculating the total size of the array.
+\paragraph{Usage}
+amemalign takes three parameters.
+\begin{itemize}
+\item
+@alignment@: the alignment to which the dynamic array needs to be aligned.
+\item
+@dim@: number of objects in the array
+\item
+@elemSize@: size of the object in the array.
+\end{itemize}
+It returns a dynamic array of objects that has the capacity to contain dim number of objects of the size of elemSize.
+The returned dynamic array is aligned to the given alignment.
+On failure, it returns a @NULL@ pointer.
+\paragraph{\lstinline{void * cmemalign( size_t alignment, size_t dim, size_t elemSize )}}
+cmemalign is a hybrid of amemalign and calloc.
+It allows programmer to allocate an aligned dynamic array of objects that is 0 filled.
+The current way to do this in other allocators is to allocate an aligned object with memalign and then fill it with 0 explicitly.
+This routine provides both features of aligning and 0 filling, implicitly.
+\paragraph{Usage}
+cmemalign takes three parameters.
+\begin{itemize}
+\item
+@alignment@: the alignment to which the dynamic array needs to be aligned.
+\item
+@dim@: number of objects in the array
+\item
+@elemSize@: size of the object in the array.
+\end{itemize}
+It returns a dynamic array of objects that has the capacity to contain dim number of objects of the size of elemSize.
+The returned dynamic array is aligned to the given alignment and is 0 filled.
+On failure, it returns a @NULL@ pointer.
+\paragraph{\lstinline{size_t malloc_alignment( void * addr )}}
+@malloc_alignment@ returns the alignment of a currently allocated dynamic object.
+It allows the programmer in memory management and personal bookkeeping.
+It helps the programmer in verifying the alignment of a dynamic object especially in a scenario similar to producer-consumer where a producer allocates a dynamic object and the consumer needs to assure that the dynamic object was allocated with the required alignment.
+\paragraph{Usage}
+@malloc_alignment@ takes one parameters.
+\begin{itemize}
+\item
+@addr@: the address of the currently allocated dynamic object.
+\end{itemize}
+@malloc_alignment@ returns the alignment of the given dynamic object.
+On failure, it return the value of default alignment of the llheap allocator.
+\paragraph{\lstinline{bool malloc_zero_fill( void * addr )}}
+@malloc_zero_fill@ returns whether a currently allocated dynamic object was initially zero filled at the time of allocation.
+It allows the programmer in memory management and personal bookkeeping.
+It helps the programmer in verifying the zero filled property of a dynamic object especially in a scenario similar to producer-consumer where a producer allocates a dynamic object and the consumer needs to assure that the dynamic object was zero filled at the time of allocation.
+\paragraph{Usage}
+@malloc_zero_fill@ takes one parameters.
+\begin{itemize}
+\item
+@addr@: the address of the currently allocated dynamic object.
+\end{itemize}
+@malloc_zero_fill@ returns true if the dynamic object was initially zero filled and return false otherwise.
+On failure, it returns false.
+\paragraph{\lstinline{size_t malloc_size( void * addr )}}
+@malloc_size@ returns the request size of a currently allocated dynamic object.
+It allows the programmer in memory management and personal bookkeeping.
+It helps the programmer in verifying the alignment of a dynamic object especially in a scenario similar to producer-consumer where a producer allocates a dynamic object and the consumer needs to assure that the dynamic object was allocated with the required size.
+Its current alternate in the other allocators is @malloc_usable_size@.
+But, @malloc_size@ is different from @malloc_usable_size@ as @malloc_usabe_size@ returns the total data capacity of dynamic object including the extra space at the end of the dynamic object.
+On the other hand, @malloc_size@ returns the size that was given to the allocator at the allocation of the dynamic object.
+This size is updated when an object is realloced, resized, or passed through a similar allocator routine.
+\paragraph{Usage}
+@malloc_size@ takes one parameters.
+\begin{itemize}
+\item
+@addr@: the address of the currently allocated dynamic object.
+\end{itemize}
+@malloc_size@ returns the request size of the given dynamic object.
+On failure, it return zero.
+\subsection{\CC Interface}
+extends @resize@ with an alignment re\-quirement.
+\noindent\textbf{Usage}
+takes three parameters.
+\begin{itemize}
+\item
+@oaddr@: address to be resized
+\item
+@nalign@: alignment requirement
+\item
+@size@: new allocation size (smaller or larger than previous)
+\end{itemize}
+It returns the address of the old or new storage with the specified new size and alignment, or @NULL@ if @size@ is zero.
 \paragraph{\lstinline{void * realloc( void * oaddr, size_t nalign, size_t size )}}
+This @realloc@ is an extension of the default @realloc@ (FIX ME: cite default @realloc@).
+In addition to reallocating an old object and preserving the data in old object, it can also realign the old object to a new alignment requirement.
+\paragraph{Usage}
+This @realloc@ takes three parameters.
+It takes an additional parameter of nalign as compared to the default @realloc@.
+\begin{itemize}
+\item
+@oaddr@: the address of the old object that needs to be reallocated.
+\item
+@nalign@: the new alignment to which the old object needs to be realigned.
+\item
+@size@: the new size requirement of the to which the old object needs to be resized.
+\end{itemize}
+It returns an object with the size and alignment given in the parameters that preserves the data in the old object.
+On failure, it returns a @NULL@ pointer.
+extends @realloc@ with an alignment re\-quirement and has the same usage as aligned @resize@.
 \subsection{\CFA Interface}
+We added some routines to the @malloc@ interface of \CFA.
+These routines can only be used in \CFA and not in our stand-alone llheap allocator as these routines use some features that are only provided by \CFA and not by C.
+It makes the allocator even more usable to the programmers.
+\CFA provides the liberty to know the returned type of a call to the allocator.
+So, mainly in these added routines, we removed the object size parameter from the routine as allocator can calculate the size of the object from the returned type.
+\subsection{\lstinline{T * malloc( void )}}
+This @malloc@ is a simplified polymorphic form of default @malloc@ (FIX ME: cite malloc).
+It does not take any parameter as compared to default @malloc@ that takes one parameter.
+\paragraph{Usage}
+This @malloc@ takes no parameters.
+It returns a dynamic object of the size of type @T@.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * aalloc( size_t dim )}}
+This @aalloc@ is a simplified polymorphic form of above @aalloc@ (FIX ME: cite aalloc).
+It takes one parameter as compared to the above @aalloc@ that takes two parameters.
+\paragraph{Usage}
+aalloc takes one parameters.
+\begin{itemize}
+\item
+@dim@: required number of objects in the array.
+\end{itemize}
+It returns a dynamic object that has the capacity to contain dim number of objects, each of the size of type @T@.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * calloc( size_t dim )}}
+This @calloc@ is a simplified polymorphic form of default @calloc@ (FIX ME: cite calloc).
+It takes one parameter as compared to the default @calloc@ that takes two parameters.
+\paragraph{Usage}
+This @calloc@ takes one parameter.
+\begin{itemize}
+\item
+@dim@: required number of objects in the array.
+\end{itemize}
+It returns a dynamic object that has the capacity to contain dim number of objects, each of the size of type @T@.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * resize( T * ptr, size_t size )}}
+This resize is a simplified polymorphic form of above resize (FIX ME: cite resize with alignment).
+It takes two parameters as compared to the above resize that takes three parameters.
+It frees the programmer from explicitly mentioning the alignment of the allocation as \CFA provides gives allocator the liberty to get the alignment of the returned type.
+\paragraph{Usage}
+This resize takes two parameters.
+\begin{itemize}
+\item
+@ptr@: address of the old object.
+\item
+@size@: the required size of the new object.
+\end{itemize}
+It returns a dynamic object of the size given in parameters.
+The returned object is aligned to the alignment of type @T@.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * realloc( T * ptr, size_t size )}}
+This @realloc@ is a simplified polymorphic form of default @realloc@ (FIX ME: cite @realloc@ with align).
+It takes two parameters as compared to the above @realloc@ that takes three parameters.
+It frees the programmer from explicitly mentioning the alignment of the allocation as \CFA provides gives allocator the liberty to get the alignment of the returned type.
+\paragraph{Usage}
+This @realloc@ takes two parameters.
+\begin{itemize}
+\item
+@ptr@: address of the old object.
+\item
+@size@: the required size of the new object.
+\end{itemize}
+It returns a dynamic object of the size given in parameters that preserves the data in the given object.
+The returned object is aligned to the alignment of type @T@.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * memalign( size_t align )}}
+This memalign is a simplified polymorphic form of default memalign (FIX ME: cite memalign).
+It takes one parameters as compared to the default memalign that takes two parameters.
+\paragraph{Usage}
+memalign takes one parameters.
+\begin{itemize}
+\item
+@align@: the required alignment of the dynamic object.
+\end{itemize}
+It returns a dynamic object of the size of type @T@ that is aligned to given parameter align.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * amemalign( size_t align, size_t dim )}}
+This amemalign is a simplified polymorphic form of above amemalign (FIX ME: cite amemalign).
+It takes two parameter as compared to the above amemalign that takes three parameters.
+\paragraph{Usage}
+amemalign takes two parameters.
+\begin{itemize}
+\item
+@align@: required alignment of the dynamic array.
+\item
+@dim@: required number of objects in the array.
+\end{itemize}
+It returns a dynamic object that has the capacity to contain dim number of objects, each of the size of type @T@.
+The returned object is aligned to the given parameter align.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * cmemalign( size_t align, size_t dim  )}}
+This cmemalign is a simplified polymorphic form of above cmemalign (FIX ME: cite cmemalign).
+It takes two parameter as compared to the above cmemalign that takes three parameters.
+\paragraph{Usage}
+cmemalign takes two parameters.
+\begin{itemize}
+\item
+@align@: required alignment of the dynamic array.
+\item
+@dim@: required number of objects in the array.
+\end{itemize}
+It returns a dynamic object that has the capacity to contain dim number of objects, each of the size of type @T@.
+The returned object is aligned to the given parameter align and is zero filled.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * aligned_alloc( size_t align )}}
+This @aligned_alloc@ is a simplified polymorphic form of default @aligned_alloc@ (FIX ME: cite @aligned_alloc@).
+It takes one parameter as compared to the default @aligned_alloc@ that takes two parameters.
+\paragraph{Usage}
+This @aligned_alloc@ takes one parameter.
+\begin{itemize}
+\item
+@align@: required alignment of the dynamic object.
+\end{itemize}
+It returns a dynamic object of the size of type @T@ that is aligned to the given parameter.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{int posix_memalign( T ** ptr, size_t align )}}
+This @posix_memalign@ is a simplified polymorphic form of default @posix_memalign@ (FIX ME: cite @posix_memalign@).
+It takes two parameters as compared to the default @posix_memalign@ that takes three parameters.
+\paragraph{Usage}
+This @posix_memalign@ takes two parameter.
+\begin{itemize}
+\item
+@ptr@: variable address to store the address of the allocated object.
+\item
+@align@: required alignment of the dynamic object.
+\end{itemize}
+It stores address of the dynamic object of the size of type @T@ in given parameter ptr.
+This object is aligned to the given parameter.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * valloc( void )}}
+This @valloc@ is a simplified polymorphic form of default @valloc@ (FIX ME: cite @valloc@).
+It takes no parameters as compared to the default @valloc@ that takes one parameter.
+\paragraph{Usage}
+@valloc@ takes no parameters.
+It returns a dynamic object of the size of type @T@ that is aligned to the page size.
+On failure, it returns a @NULL@ pointer.
+\subsection{\lstinline{T * pvalloc( void )}}
+\paragraph{Usage}
+@pvalloc@ takes no parameters.
+It returns a dynamic object of the size that is calculated by rounding the size of type @T@.
+The returned object is also aligned to the page size.
+On failure, it returns a @NULL@ pointer.
+\subsection{Alloc Interface}
+In addition to improve allocator interface both for \CFA and our stand-alone allocator llheap in C.
+We also added a new alloc interface in \CFA that increases usability of dynamic memory allocation.
+This interface helps programmers in three major ways.
+\begin{itemize}
+\item
+Routine Name: alloc interface frees programmers from remembering different routine names for different kind of dynamic allocations.
+\item
+Parameter Positions: alloc interface frees programmers from remembering parameter positions in call to routines.
+\item
+Object Size: alloc interface does not require programmer to mention the object size as \CFA allows allocator to determine the object size from returned type of alloc call.
+\end{itemize}
+Alloc interface uses polymorphism, backtick routines (FIX ME: cite backtick) and ttype parameters of \CFA (FIX ME: cite ttype) to provide a very simple dynamic memory allocation interface to the programmers.
+The new interface has just one routine name alloc that can be used to perform a wide range of dynamic allocations.
+The parameters use backtick functions to provide a similar-to named parameters feature for our alloc interface so that programmers do not have to remember parameter positions in alloc call except the position of dimension (dim) parameter.
+\subsection{Routine: \lstinline{T * alloc( ...
+)}}
+Call to alloc without any parameter returns one object of size of type @T@ allocated dynamically.
+Only the dimension (dim) parameter for array allocation has the fixed position in the alloc routine.
+If programmer wants to allocate an array of objects that the required number of members in the array has to be given as the first parameter to the alloc routine.
+alloc routine accepts six kinds of arguments.
+Using different combinations of than parameters, different kind of allocations can be performed.
+Any combination of parameters can be used together except @`realloc@ and @`resize@ that should not be used simultaneously in one call to routine as it creates ambiguity about whether to reallocate or resize a currently allocated dynamic object.
+If both @`resize@ and @`realloc@ are used in a call to alloc then the latter one will take effect or unexpected resulted might be produced.
+\paragraph{Dim}
+This is the only parameter in the alloc routine that has a fixed-position and it is also the only parameter that does not use a backtick function.
+It has to be passed at the first position to alloc call in-case of an array allocation of objects of type @T@.
+It represents the required number of members in the array allocation as in \CFA's @aalloc@ (FIX ME: cite aalloc).
+This parameter should be of type @size_t@.
+Example: @int a = alloc( 5 )@
+This call will return a dynamic array of five integers.
+\paragraph{Align}
+This parameter is position-free and uses a backtick routine align (@`align@).
+The parameter passed with @`align@ should be of type @size_t@.
+If the alignment parameter is not a power of two or is less than the default alignment of the allocator (that can be found out using routine libAlign in \CFA) then the passed alignment parameter will be rejected and the default alignment will be used.
+Example: @int b = alloc( 5 , 64`align )@
+This call will return a dynamic array of five integers.
+It will align the allocated object to 64.
+\paragraph{Fill}
+This parameter is position-free and uses a backtick routine fill (@`fill@).
+In case of @realloc@, only the extra space after copying the data in the old object will be filled with given parameter.
+Three types of parameters can be passed using `fill.
+\begin{itemize}
+\item
+@char@: A char can be passed with @`fill@ to fill the whole dynamic allocation with the given char recursively till the end of required allocation.
+\item
+Object of returned type: An object of type of returned type can be passed with @`fill@ to fill the whole dynamic allocation with the given object recursively till the end of required allocation.
+\item
+Dynamic object of returned type: A dynamic object of type of returned type can be passed with @`fill@ to fill the dynamic allocation with the given dynamic object.
+In this case, the allocated memory is not filled recursively till the end of allocation.
+The filling happen until the end object passed to @`fill@ or the end of requested allocation reaches.
+\end{itemize}
+Example: @int b = alloc( 5 , 'a'`fill )@
+This call will return a dynamic array of five integers.
+It will fill the allocated object with character 'a' recursively till the end of requested allocation size.
+Example: @int b = alloc( 5 , 4`fill )@
+This call will return a dynamic array of five integers.
+It will fill the allocated object with integer 4 recursively till the end of requested allocation size.
+Example: @int b = alloc( 5 , a`fill )@ where @a@ is a pointer of int type
+This call will return a dynamic array of five integers.
+It will copy data in a to the returned object non-recursively until end of a or the newly allocated object is reached.
+\paragraph{Resize}
+This parameter is position-free and uses a backtick routine resize (@`resize@).
+It represents the old dynamic object (oaddr) that the programmer wants to
+\begin{itemize}
+\item
+resize to a new size.
+\item
+realign to a new alignment
+\item
+fill with something.
+\end{itemize}
+The data in old dynamic object will not be preserved in the new object.
+The type of object passed to @`resize@ and the returned type of alloc call can be different.
+Example: @int b = alloc( 5 , a`resize )@
+This call will resize object a to a dynamic array that can contain 5 integers.
+Example: @int b = alloc( 5 , a`resize , 32`align )@
+This call will resize object a to a dynamic array that can contain 5 integers.
+The returned object will also be aligned to 32.
+Example: @int b = alloc( 5 , a`resize , 32`align , 2`fill )@
+This call will resize object a to a dynamic array that can contain 5 integers.
+The returned object will also be aligned to 32 and will be filled with 2.
+\paragraph{Realloc}
+This parameter is position-free and uses a backtick routine @realloc@ (@`realloc@).
+It represents the old dynamic object (oaddr) that the programmer wants to
+\begin{itemize}
+\item
+realloc to a new size.
+\item
+realign to a new alignment
+\item
+fill with something.
+\end{itemize}
+The data in old dynamic object will be preserved in the new object.
+The type of object passed to @`realloc@ and the returned type of alloc call cannot be different.
+Example: @int b = alloc( 5 , a`realloc )@
+This call will realloc object a to a dynamic array that can contain 5 integers.
+Example: @int b = alloc( 5 , a`realloc , 32`align )@
+This call will realloc object a to a dynamic array that can contain 5 integers.
+The returned object will also be aligned to 32.
+Example: @int b = alloc( 5 , a`realloc , 32`align , 2`fill )@
+This call will resize object a to a dynamic array that can contain 5 integers.
+The returned object will also be aligned to 32.
+The extra space after copying data of a to the returned object will be filled with 2.
+The following extensions take advantage of overload polymorphism in the \CFA type-system.
+The key safety advantage of the \CFA type system is using the return type to select overloads;
+hence, a polymorphic routine knows the returned type and its size.
+This capability is used to remove the object size parameter and correctly cast the return storage to match the result type.
+For example, the following is the \CFA wrapper for C @malloc@:
+\begin{cfa}
+forall( T & | sized(T) ) {
+        T * malloc( void ) {
+                if ( _Alignof(T) <= libAlign() ) return @(T *)@malloc( @sizeof(T)@ ); // C allocation
+                else return @(T *)@memalign( @_Alignof(T)@, @sizeof(T)@ ); // C allocation
+        } // malloc
+\end{cfa}
+and is used as follows:
+\begin{lstlisting}
+int * i = malloc();
+double * d = malloc();
+struct Spinlock { ... } __attribute__(( aligned(128) ));
+Spinlock * sl = malloc();
+\end{lstlisting}
+where each @malloc@ call provides the return type as @T@, which is used with @sizeof@, @_Alignof@, and casting the storage to the correct type.
+This interface removes many of the common allocation errors in C programs.
+\VRef[Figure]{f:CFADynamicAllocationAPI} show the \CFA wrappers for the equivalent C/\CC allocation routines with same semantic behaviour.
+\begin{figure}
+\begin{lstlisting}
+T * malloc( void );
+T * aalloc( size_t dim );
+T * calloc( size_t dim );
+T * resize( T * ptr, size_t size );
+T * realloc( T * ptr, size_t size );
+T * memalign( size_t align );
+T * amemalign( size_t align, size_t dim );
+T * cmemalign( size_t align, size_t dim  );
+T * aligned_alloc( size_t align );
+int posix_memalign( T ** ptr, size_t align );
+T * valloc( void );
+T * pvalloc( void );
+\end{lstlisting}
+\caption{\CFA C-Style Dynamic-Allocation API}
+\label{f:CFADynamicAllocationAPI}
+\end{figure}
+In addition to the \CFA C-style allocator interface, a new allocator interface is provided to further increase orthogonality and usability of dynamic-memory allocation.
+This interface helps programmers in three ways.
+\begin{itemize}
+\item
+naming: \CFA regular and @ttype@ polymorphism is used to encapsulate a wide range of allocation functionality into a single routine name, so programmers do not have to remember multiple routine names for different kinds of dynamic allocations.
+\item
+named arguments: individual allocation properties are specified using postfix function call, so programmers do have to remember parameter positions in allocation calls.
+\item
+object size: like the \CFA C-style interface, programmers do not have to specify object size or cast allocation results.
+\end{itemize}
+Note, postfix function call is an alternative call syntax, using backtick @`@, where the argument appears before the function name, \eg
+\begin{cfa}
+duration ?@`@h( int h );                // ? denote the position of the function operand
+duration ?@`@m( int m );
+duration ?@`@s( int s );
+duration dur = 3@`@h + 42@`@m + 17@`@s;
+\end{cfa}
+@ttype@ polymorphism is similar to \CC variadic templates.
+\paragraph{\lstinline{T * alloc( ... )} or \lstinline{T * alloc( size_t dim, ... )}}
+is overloaded with a variable number of specific allocation routines, or an integer dimension parameter followed by a variable number specific allocation routines.
+A call without parameters returns a dynamically allocated object of type @T@ (@malloc@).
+A call with only the dimension (dim) parameter returns a dynamically allocated array of objects of type @T@ (@aalloc@).
+The variable number of arguments consist of allocation properties, which can be combined to produce different kinds of allocations.
+The only restriction is for properties @realloc@ and @resize@, which cannot be combined.
+The allocation property functions are:
+\subparagraph{\lstinline{T_align ?`align( size_t alignment )}}
+to align the allocation.
+The alignment parameter must be $\ge$ the default alignment (@libAlign()@ in \CFA) and a power of two, \eg:
+\begin{cfa}
+int * i0 = alloc( @4096`align@ );  sout | i0 | nl;
+int * i1 = alloc( 3, @4096`align@ );  sout | i1; for (i; 3 ) sout | &i1[i]; sout | nl;
+x555555572000
+x555555574000 0x555555574000 0x555555574004 0x555555574008
+\end{cfa}
+returns a dynamic object and object array aligned on a 4096-byte boundary.
+\subparagraph{\lstinline{S_fill(T) ?`fill ( /* various types */ )}}
+to initialize storage.
+There are three ways to fill storage:
+\begin{enumerate}
+\item
+A char fills each byte of each object.
+\item
+An object of the returned type fills each object.
+\item
+An object array pointer fills some or all of the corresponding object array.
+\end{enumerate}
+For example:
+\begin{cfa}[numbers=left]
+int * i0 = alloc( @0n`fill@ );  sout | *i0 | nl;  // disambiguate 0
+int * i1 = alloc( @5`fill@ );  sout | *i1 | nl;
+int * i2 = alloc( @'\xfe'`fill@ ); sout | hex( *i2 ) | nl;
+int * i3 = alloc( 5, @5`fill@ );  for ( i; 5 ) sout | i3[i]; sout | nl;
+int * i4 = alloc( 5, @0xdeadbeefN`fill@ );  for ( i; 5 ) sout | hex( i4[i] ); sout | nl;
+int * i5 = alloc( 5, @i3`fill@ );  for ( i; 5 ) sout | i5[i]; sout | nl;
+int * i6 = alloc( 5, @[i3, 3]`fill@ );  for ( i; 5 ) sout | i6[i]; sout | nl;
+\end{cfa}
+\begin{lstlisting}[numbers=left]
+xfefefefe
+5 5 5 5
+xdeadbeef 0xdeadbeef 0xdeadbeef 0xdeadbeef 0xdeadbeef
+5 5 5 5
+5 5 -555819298 -555819298  // two undefined values
+\end{lstlisting}
+Examples 1 to 3, fill an object with a value or characters.
+Examples 4 to 7, fill an array of objects with values, another array, or part of an array.
+\subparagraph{\lstinline{S_resize(T) ?`resize( void * oaddr )}}
+used to resize, realign, and fill, where the old object data is not copied to the new object.
+The old object type may be different from the new object type, since the values are not used.
+For example:
+\begin{cfa}[numbers=left]
+int * i = alloc( @5`fill@ );  sout | i | *i;
+i = alloc( @i`resize@, @256`align@, @7`fill@ );  sout | i | *i;
+double * d = alloc( @i`resize@, @4096`align@, @13.5`fill@ );  sout | d | *d;
+\end{cfa}
+\begin{lstlisting}[numbers=left]
+x55555556d5c0 5
+x555555570000 7
+x555555571000 13.5
+\end{lstlisting}
+Examples 2 to 3 change the alignment, fill, and size for the initial storage of @i@.
+\begin{cfa}[numbers=left]
+int * ia = alloc( 5, @5`fill@ );  for ( i; 5 ) sout | ia[i]; sout | nl;
+ia = alloc( 10, @ia`resize@, @7`fill@ ); for ( i; 10 ) sout | ia[i]; sout | nl;
+sout | ia; ia = alloc( 5, @ia`resize@, @512`align@, @13`fill@ ); sout | ia; for ( i; 5 ) sout | ia[i]; sout | nl;;
+ia = alloc( 3, @ia`resize@, @4096`align@, @2`fill@ );  sout | ia; for ( i; 3 ) sout | &ia[i] | ia[i]; sout | nl;
+\end{cfa}
+\begin{lstlisting}[numbers=left]
+5 5 5 5
+7 7 7 7 7 7 7 7 7
+x55555556d560 0x555555571a00 13 13 13 13 13
+x555555572000 0x555555572000 2 0x555555572004 2 0x555555572008 2
+\end{lstlisting}
+Examples 2 to 4 change the array size, alignment and fill for the initial storage of @ia@.
+\subparagraph{\lstinline{S_realloc(T) ?`realloc( T * a ))}}
+used to resize, realign, and fill, where the old object data is copied to the new object.
+The old object type must be the same as the new object type, since the values used.
+Note, for @fill@, only the extra space after copying the data from the old object is filled with the given parameter.
+For example:
+\begin{cfa}[numbers=left]
+int * i = alloc( @5`fill@ );  sout | i | *i;
+i = alloc( @i`realloc@, @256`align@ );  sout | i | *i;
+i = alloc( @i`realloc@, @4096`align@, @13`fill@ );  sout | i | *i;
+\end{cfa}
+\begin{lstlisting}[numbers=left]
+x55555556d5c0 5
+x555555570000 5
+x555555571000 5
+\end{lstlisting}
+Examples 2 to 3 change the alignment for the initial storage of @i@.
+The @13`fill@ for example 3 does nothing because no extra space is added.
+\begin{cfa}[numbers=left]
+int * ia = alloc( 5, @5`fill@ );  for ( i; 5 ) sout | ia[i]; sout | nl;
+ia = alloc( 10, @ia`realloc@, @7`fill@ ); for ( i; 10 ) sout | ia[i]; sout | nl;
+sout | ia; ia = alloc( 1, @ia`realloc@, @512`align@, @13`fill@ ); sout | ia; for ( i; 1 ) sout | ia[i]; sout | nl;;
+ia = alloc( 3, @ia`realloc@, @4096`align@, @2`fill@ );  sout | ia; for ( i; 3 ) sout | &ia[i] | ia[i]; sout | nl;
+\end{cfa}
+\begin{lstlisting}[numbers=left]
+5 5 5 5
+5 5 5 5 7 7 7 7 7
+x55555556c560 0x555555570a00 5
+x555555571000 0x555555571000 5 0x555555571004 2 0x555555571008 2
+\end{lstlisting}
+Examples 2 to 4 change the array size, alignment and fill for the initial storage of @ia@.
+The @13`fill@ for example 3 does nothing because no extra space is added.
+These \CFA allocation features are used extensively in the development of the \CFA runtime.

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