Beispiel #1
0
void bli_pool_alloc_block( siz_t   block_size,
                           siz_t   align_size,
                           pblk_t* block )
{
	void* buf_sys;
	void* buf_align;

	// Allocate the block. We add the alignment size to ensure we will
	// have enough usable space after alignment.
	buf_sys   = bli_malloc( block_size + align_size );
	buf_align = buf_sys;

	// Advance the pointer to achieve the necessary alignment, if it is not
	// already aligned.
	if ( bli_is_unaligned_to( buf_sys, align_size ) )
	{
		// C99's stdint.h guarantees that a void* can be safely cast to a
		// uintptr_t and then back to a void*, hence the casting of buf_sys
		// and align_size to uintptr_t. buf_align is initially cast to char*
		// to allow pointer arithmetic in units of bytes, and then advanced
		// to the next nearest alignment boundary, and finally cast back to
		// void* before being stored. Notice that the arithmetic works even
		// if the alignment value is not a power of two.
		buf_align = ( void* )(   ( char*     )buf_align +
		                       ( ( uintptr_t )align_size -
		                         ( uintptr_t )buf_sys %
		                         ( uintptr_t )align_size )
		                     );
	}
	
	// Save the results in the pblk_t structure.
	bli_pblk_set_buf_sys( buf_sys, block );
	bli_pblk_set_buf_align( buf_align, block );
}
Beispiel #2
0
void bli_pool_alloc_block( siz_t   block_size,
                           siz_t   align_size,
                           pblk_t* block )
{
	void* buf_sys;
	void* buf_align;

	// Allocate the block. We add the alignment size to ensure we will
	// have enough usable space after alignment.
	buf_sys   = bli_malloc( block_size + align_size );
	buf_align = buf_sys;

	// Advance the pointer to achieve the necessary alignment, if it
	// is not already aligned.
	if ( bli_is_unaligned_to( ( uintptr_t )buf_sys, ( uintptr_t )align_size ) )
	{
		// Notice that this works even if the alignment is not a power of two.
		buf_align += (   ( uintptr_t )align_size - 
		               ( ( uintptr_t )buf_sys % align_size ) );
	}
	
	// Save the results in the pblk_t structure.
	bli_pblk_set_buf_sys( buf_sys, block );
	bli_pblk_set_buf_align( buf_align, block );
}