err_t bli_check_object_alias_of( obj_t* a, obj_t* b )
{
err_t e_val = BLIS_SUCCESS;
if ( !bli_obj_is_alias_of( *a, *b ) )
e_val = BLIS_EXPECTED_OBJECT_ALIAS;
return e_val;
}
void bli_unpackv_int( obj_t* p,
obj_t* a,
cntx_t* cntx,
unpackv_t* cntl )
{
// The unpackv operation consists of an optional casting post-process.
// (This post-process is analogous to the cast pre-process in packv.)
// Here are the following possible ways unpackv can execute:
// 1. unpack and cast: Unpack to a temporary vector c and then cast
// c to a.
// 2. unpack only: Unpack directly to vector a since typecasting is
// not needed.
// 3. cast only: Not yet supported / not used.
// 4. no-op: The control tree directs us to skip the unpack operation
// entirely. No action is taken.
obj_t c;
varnum_t n;
impl_t i;
FUNCPTR_T f;
// Check parameters.
if ( bli_error_checking_is_enabled() )
bli_unpackv_check( p, a, cntx );
// Sanity check; A should never have a zero dimension. If we must support
// it, then we should fold it into the next alias-and-early-exit block.
if ( bli_obj_has_zero_dim( *a ) ) bli_abort();
// First check if we are to skip this operation because the control tree
// is NULL, and if so, simply return.
if ( cntl_is_noop( cntl ) )
{
return;
}
// If p was aliased to a during the pack stage (because it was already
// in an acceptable packed/contiguous format), then no unpack is actually
// necessary, so we return.
if ( bli_obj_is_alias_of( *p, *a ) )
{
return;
}
// Now, if we are not skipping the unpack operation, then the only
// question left is whether we are to typecast vector a after unpacking.
if ( bli_obj_datatype( *p ) != bli_obj_datatype( *a ) )
bli_abort();
/*
if ( bli_obj_datatype( *p ) != bli_obj_datatype( *a ) )
{
// Initialize an object c for the intermediate typecast vector.
bli_unpackv_init_cast( p,
a,
&c );
}
else
*/
{
// If no cast is needed, then aliasing object c to the original
// vector serves as a minor optimization. This causes the unpackv
// implementation to unpack directly into vector a.
bli_obj_alias_to( *a, c );
}
// Now we are ready to proceed with the unpacking.
// Extract the variant number and implementation type.
n = cntl_var_num( cntl );
i = cntl_impl_type( cntl );
// Index into the variant array to extract the correct function pointer.
f = vars[n][i];
// Invoke the variant.
f( p,
&c,
cntx,
cntl );
// Now, if necessary, we cast the contents of c to vector a. If casting
// was not necessary, then we are done because the call to the unpackv
// implementation would have unpacked directly to vector a.
/*
if ( bli_obj_datatype( *p ) != bli_obj_datatype( *a ) )
{
// Copy/typecast vector c to vector a.
// NOTE: Here, we use copynzv instead of copym because, in the cases
// where we are unpacking/typecasting a real vector c to a complex
// vector a, we want to touch only the real components of a, rather
// than also set the imaginary components to zero. This comes about
// because of the fact that, if we are unpacking real-to-complex,
// then it is because all of the computation occurred in the real
// domain, and so we would want to leave whatever imaginary values
// there are in vector a untouched. Notice that for unpackings that
// entail complex-to-complex data movements, the copynzv operation
// behaves exactly as copym, so no use cases are lost (at least none
// that I can think of).
bli_copynzv( &c,
a );
// NOTE: The above code/comment is outdated. What should happen is
// as follows:
// - If dt(a) is complex and dt(p) is real, then create an alias of
// a and then tweak it so that it looks like a real domain object.
// This will involve:
// - projecting the datatype to real domain
// - scaling both the row and column strides by 2
// ALL OF THIS should be done in the front-end, NOT here, as
// unpackv() won't even be needed in that case.
}
*/
}
