Details:
- After merging PR #303, at Isuru's request, I removed the use of
BLIS_EXPORT_BLIS from all function prototypes *except* those that we
potentially wish to be exported in shared/dynamic libraries. In other
words, I removed the use of BLIS_EXPORT_BLIS from all prototypes of
functions that can be considered private or for internal use only.
This is likely the last big modification along the path towards
implementing the functionality spelled out in issue #248. Thanks
again to Isuru Fernando for his initial efforts of sprinkling the
export macros throughout BLIS, which made removing them where
necessary relatively painless. Also, I'd like to thank Tony Kelman,
Nathaniel Smith, Ian Henriksen, Marat Dukhan, and Matthew Brett for
participating in the initial discussion in issue #37 that was later
summarized and restated in issue #248.
- CREDITS file update.
Details:
- Removed explicit reference to The University of Texas at Austin in the
third clause of the license comment blocks of all relevant files and
replaced it with a more all-encompassing "copyright holder(s)".
- Removed duplicate words ("derived") from a few kernels' license
comment blocks.
- Homogenized license comment block in kernels/zen/3/bli_gemm_small.c
with format of all other comment blocks.
Details:
- Removed four trailing spaces after "BLIS" that occurs in most files'
commented-out license headers.
- Added UT copyright lines to some files. (These files previously had
only AMD copyright lines but were contributed to by both UT and AMD.)
- In some files' copyright lines, expanded 'The University of Texas' to
'The University of Texas at Austin'.
- Fixed various typos/misspellings in some license headers.
Details:
- Defined a new struct datatype, rntm_t (runtime), to house the thrloop
field of the cntx_t (context). The thrloop array holds the number of
ways of parallelism (thread "splits") to extract per level-3
algorithmic loop until those values can be used to create a
corresponding node in the thread control tree (thrinfo_t structure),
which (for any given level-3 invocation) usually happens by the time
the macrokernel is called for the first time.
- Relocating the thrloop from the cntx_t remedies a thread-safety issue
when invoking level-3 operations from two or more application threads.
The race condition existed because the cntx_t, a pointer to which is
usually queried from the global kernel structure (gks), is supposed to
be a read-only. However, the previous code would write to the cntx_t's
thrloop field *after* it had been queried, thus violating its read-only
status. In practice, this would not cause a problem when a sequential
application made a multithreaded call to BLIS, nor when two or more
application threads used the same parallelization scheme when calling
BLIS, because in either case all application theads would be using
the same ways of parallelism for each loop. The true effects of the
race condition were limited to situations where two or more application
theads used *different* parallelization schemes for any given level-3
call.
- In remedying the above race condition, the application or calling
library can now specify the parallelization scheme on a per-call basis.
All that is required is that the thread encode its request for
parallelism into the rntm_t struct prior to passing the address of the
rntm_t to one of the expert interfaces of either the typed or object
APIs. This allows, for example, one application thread to extract 4-way
parallelism from a call to gemm while another application thread
requests 2-way parallelism. Or, two threads could each request 4-way
parallelism, but from different loops.
- A rntm_t* parameter has been added to the function signatures of most
of the level-3 implementation stack (with the most notable exception
being packm) as well as all level-1v, -1d, -1f, -1m, and -2 expert
APIs. (A few internal functions gained the rntm_t* parameter even
though they currently have no use for it, such as bli_l3_packm().)
This required some internal calls to some of those functions to
be updated since BLIS was already using those operations internally
via the expert interfaces. For situations where a rntm_t object is
not available, such as within packm/unpackm implementations, NULL is
passed in to the relevant expert interfaces. This is acceptable for
now since parallelism is not obtained for non-level-3 operations.
- Revamped how global parallelism is encoded. First, the conventional
environment variables such as BLIS_NUM_THREADS and BLIS_*_NT are only
read once, at library initialization. (Thanks to Nathaniel Smith for
suggesting this to avoid repeated calls getenv(), which can be slow.)
Those values are recorded to a global rntm_t object. Public APIs, in
bli_thread.c, are still available to get/set these values from the
global rntm_t, though now the "set" functions have additional logic
to ensure that the values are set in a synchronous manner via a mutex.
If/when NULL is passed into an expert API (meaning the user opted to
not provide a custom rntm_t), the values from the global rntm_t are
copied to a local rntm_t, which is then passed down the function stack.
Calling a basic API is equivalent to calling the expert APIs with NULL
for the cntx and rntm parameters, which means the semantic behavior of
these basic APIs (vis-a-vis multithreading) is unchanged from before.
- Renamed bli_cntx_set_thrloop_from_env() to bli_rntm_set_ways_for_op()
and reimplemented, with the function now being able to treat the
incoming rntm_t in a manner agnostic to its origin--whether it came
from the application or is an internal copy of the global rntm_t.
- Removed various global runtime APIs for setting the number of ways of
parallelism for individual loops (e.g. bli_thread_set_*_nt()) as well
as the corresponding "get" functions. The new model simplifies these
interfaces so that one must either set the total number of threads, OR
set all of the ways of parallelism for each loop simultaneously (in a
single function call).
- Updated sandbox/ref99 according to above changes.
- Rewrote/augmented docs/Multithreading.md to document the three methods
(and two specific ways within each method) of requesting parallelism
in BLIS.
- Removed old, disabled code from bli_l3_thrinfo.c.
- Whitespace changes to code (e.g. bli_obj.c) and docs/BuildSystem.md.
Details:
- Added bli_setgetijm.c, which defines bli_setijm(), bli_getijm(), and
related functions that can be used to read and write individual
elements of an obj_t.
- Defined a new function, bli_obj_create_conf_to(), in bli_obj.c that will
create a new object with dimensions conformal to an existing object.
Transposition and conjugation states on the existing object are ignored,
as are structure and uplo fields.
- Defined a new function, bli_datatype_string(), in bli_obj.c that returns
a char* to a string representation of the name of each num_t datatype.
For example, BLIS_DOUBLE is "double" and BLIS_DCOMPLEX is "dcomplex".
BLIS_INT is included (as "int"), but BLIS_CONSTANT is not, and thus is
not a valid input argument to bli_datatype_string().
- Added calls to bli_init_once() to various functions in bli_obj.c, the
most important of which was bli_obj_create_without_buffer().
- Removed unintended/extra newline from the end of printv output.
- Whitespace changes to
- frame/base/bli_machval.c
- frame/base/bli_machval.h
- frame/0/copysc/bli_copysc.c
- Trivial changes to README.md and common.mk.
Details:
- Fixed a race condition in self-initialization whereby the bli_is_init
static variable could be erroneously read as TRUE by thread 1 while
thread 0 is still executing bli_init_apis(), thus allowing thread 1 to
use the library before it is actually ready. Thanks to to Minh Quan Ho
and Devin Matthews for pointing out this issue.
- Part of the solution to the aforementioned race condition was involved
replacing the runtime initialization of the global scalar constants
(e.g., BLIS_ONE, BLIS_ZERO, etc.) in bli_const.c with a static
initialization of those same constants. This eliminates the need for
bli_const_init() altogether. (The static initialization is made concise
via preprocess macros.)
- Defined bli_gks_query_cntx_noinit(), which behaves just like
bli_gks_query_cntx(), except that it does not call bli_init_once(). This
function is called in lieu of bli_gks_query_cntx() in bli_ind_init() and
bli_memsys_init() so as to not result in any recursion into
bli_init_once().
- Removed BLIS_ONE_HALF, BLIS_MINUS_ONE_HALF global scalar constants.
They have no use in BLIS or its test products, and we have little reason
to believe they are used by others.
- Removed testsuite/out file, which was accidentally committed as part
of 70640a3.
Details:
- Defined two new functions in bli_init.c: bli_init_once() and
bli_finalize_once(). Each is implemented with pthread_once(), which
guarantees that, among the threads that pass in the same pthread_once_t
data structure, exactly one thread will execute a user-defined function.
(Thus, there is now a runtime dependency against libpthread even when
multithreading is not enabled at configure-time.)
- Added calls to bli_init_once() to top-level user APIs for all
computational operations as well as many other functions in BLIS to
all but guarantee that BLIS will self-initialize through the normal
use of its functions.
- Rewrote and simplified bli_init() and bli_finalize() and related
functions.
- Added -lpthread to LDFLAGS in common.mk.
- Modified the bli_init_auto()/_finalize_auto() functions used by the
BLAS compatibility layer to take and return no arguments. (The
previous API that tracked whether BLIS was initialized, and then
only finalized if it was initialized in the same function, was too
cute by half and borderline useless because by default BLIS stays
initialized when auto-initialized via the compatibility layer.)
- Removed static variables that track initialization of the sub-APIs in
bli_const.c, bli_error.c, bli_init.c, bli_memsys.c, bli_thread, and
bli_ind.c. We don't need to track initialization at the sub-API level,
especially now that BLIS can self-initialize.
- Added a critical section around the changing of the error checking
level in bli_error.c.
- Deprecated bli_ind_oper_has_avail() as well as all functions
bli_<opname>_ind_get_avail(), where <opname> is a level-3 operation
name. These functions had no use cases within BLIS and likely none
outside of BLIS.
- Commented out calls to bli_init() and bli_finalize() in testsuite's
main() function, and likewise for standalone test drivers in 'test'
directory, so that self-initialization is exercised by default.
Details:
- Replaced all instances of bli_malloc() and bli_free() with one of:
- bli_malloc_pool()/bli_free_pool()
- bli_malloc_user()/bli_free_user()
- bli_malloc_intl()/bli_free_intl()
each of which can be configured to call malloc()/free() substitutes,
so long as the substitute functions have the same function type
signatures as malloc() and free() defined by C's stdlib.h. The _pool()
function is called when allocating blocks for the memory pools (used
for packing buffers, primarily), the _user() function is called when
obj_t's are created (via bli_obj_create() and friends), and the _intl()
function is called for internal use by BLIS, such as when creating
control tree nodes or temporary buffers for manipulating internal data
structures. Substitutes for any of the three types of bli_malloc() may
be specified by #defining the following pairs of cpp macros in
bli_kernel.h:
- BLIS_MALLOC_POOL/BLIS_FREE_POOL
- BLIS_MALLOC_USER/BLIS_FREE_USER
- BLIS_MALLOC_INTL/BLIS_FREE_INTL
to be the name of the substitute functions. (Obviously, the object
code that contains these functions must be provided at link-time.)
These macros default to malloc() and free(). Subsitute functions are
also automatically prototyped by BLIS (in bli_malloc_prototypes.h).
- Removed definitions for bli_malloc() and bli_free().
- Note that bli_malloc_pool() and bli_malloc_user() are now defined in
terms of a new function, bli_malloc_align(), which aligns memory to an
arbitrary (power of two) alignment boundary, but does so manually,
whereas before alignment was performed behind the scenes by
posix_memalign(). Currently, bli_malloc_intl() is defined in terms
of bli_malloc_noalign(), which serves as a simple wrapper to the
designated function that is passed in (e.g. BLIS_MALLOC_INTL).
Similarly, there are bli_free_align() and bli_free_noalign(), which
are used in concert with their bli_malloc_*() counterparts.
Details:
- Applied a patch submitted by Devin Matthews that:
- implements subtle changes to handling of somewhat unusual cases of
row and column strides to accommodate certail tensor cases, which
includes adding dimension parameters to _is_col_tilted() and
_is_row_tilted() macros,
- simplifies how buffers are sized when requested BLIS-allocated
objects,
- re-consolidates bli_adjust_strides_*() into one function, and
- defines 'restrict' keyword as a "nothing" macro for C++ and pre-C99
environments.
Details:
- Separated bli_adjust_strides() into _alloc() and _attach() flavors so
that the latter can avoid a test performed by the former, in which the
rs and cs are overridden and set to zero if either matrix dimension is
zero. Actually, we also disable this overridding behavior, even for the
_alloc() case, since keeping the original strides (probably) does not
hurt anything. The original code has been kept commented-out, though,
in case an unintended consequence is later discovered.
- Fixed a typo in an error check for general stride cases where rs == cs.
Details:
- Added an imaginary stride field ("is") to obj_t.
- Renamed bli_obj_set_incs() macro to bli_obj_set_strides().
- Defined bli_obj_imag_stride() and bli_obj_set_imag_stride() and
added invocations in key locations.
- Added some basic error-checking related to imaginary stride.
- For now, imaginary stride will not be exposed into the most-used
BLIS APIs such as bli_obj_create(), and certainly not the
computational APIs such as bli_dgemm().
Details:
- Updated copyright headers to include "at Austin" in the name of the
University of Texas.
- Updated the copyright years of a few headers to 2014 (from 2011 and
2012).
Details:
- Added infrastructure to support a new scalar representation, whereby
every object contains an internal scalar that defaults to 1.0. This
facilitates passing scalars around without having to house them in
separate objects. These "attached" scalars are stored in the internal
atom_t field of the obj_t struct, and are always stored to be the same
datatype as the object to which they are attached. Level-3 variants no
longer take scalar arguments, however, level-3 internal back-ends stll
do; this is so that the calling function can perform subproblems such
as C := C - alpha * A * B on-the-fly without needing to change either
of the scalars attached to A or B.
- Removed scalar argument from packm_int().
- Observe and apply attached scalars in scalm_int(), and removed scalar
from interface of scalm_unb_var1().
- Renamed the following functions (and corresponding invocations):
bli_obj_init_scalar_copy_of()
-> bli_obj_scalar_init_detached_copy_of()
bli_obj_init_scalar() -> bli_obj_scalar_init_detached()
bli_obj_create_scalar_with_attached_buffer()
-> bli_obj_create_1x1_with_attached_buffer()
bli_obj_scalar_equals() -> bli_obj_equals()
- Defined new functions:
bli_obj_scalar_detach()
bli_obj_scalar_attach()
bli_obj_scalar_apply_scalar()
bli_obj_scalar_reset()
bli_obj_scalar_has_nonzero_imag()
bli_obj_scalar_equals()
- Placed all bli_obj_scalar_* functions in a new file, bli_obj_scalar.c.
- Renamed the following macros:
bli_obj_scalar_buffer() -> bli_obj_buffer_for_1x1()
bli_obj_is_scalar() -> bli_obj_is_1x1()
- Defined new macros to set and copy internal scalars between objects:
bli_obj_set_internal_scalar()
bli_obj_copy_internal_scalar()
- In level-3 internal back-ends, added conditional blocks where alpha and
beta are checked for non-unit-ness. Those values for alpha and beta are
applied to the scalars attached to aliases of A/B/C, as appropriate,
before being passed into the variant specified by the control tree.
- In level-3 blocked variants, pass BLIS_ONE into subproblems instead of
alpha and/or beta.
- In level-3 macro-kernels, changed how scalars are obtained. Now, scalars
attached to A and B are multiplied together to obtain alpha, while beta
is obtained directly from C.
- In level-3 front-ends, removed old function calls meant to provide
future support for mixed domain/precision. These can be added back later
once that functionality is given proper treatment. Also, removed the
creating of copy-casts of alpha and beta since typecasting of scalars
is now implicitly handled in the internal back-ends when alpha and
beta are applied to the attached scalars.
Details:
- Redefined dim_t and inc_t in terms of gint_t (instead of guint_t).
This will facilitate interoperability with Fortran in the future.
(Fortran does not support unsigned integers.)
- Redefined many instances of stride-related macros so that they return
or use the absolute value of the strides, rather than the raw strides
which may now be signed. Added new macros bli_is_row_stored_f() and
bli_is_col_stored_f(), which assume positive (forward-oriented) strides,
and changed the packm_blk_var[23] variants to use these macros instead
of the existing bli_is_row_stored(), bli_is_col_stored().
- Added/adjusted typecasting to to various functions/macros, including
bli_obj_alloc_buffer(), bli_obj_buffer_at_off(), and various pointer-
related macros in bli_param_macro_defs.h.
- Redefined bli_convert_blas_incv() macro so that the BLAS compatibility
layer properly handles situations where vector increments are negative.
Thanks to Vladimir Sukharev for pointing out this issue.
- Changed type of increment parameters in bli_adjust_strides() from dim_t
to inc_t. Likewise in bli_check_matrix_strides().
- Defined bli_check_matrix_object(), which checks for negative strides.
- Redefined bli_check_scalar_object() and bli_check_vector_object() so
that they also check for negative stride.
- Added instances of bli_check_matrix_object() to various operations'
_check routines.
Details:
- Added new memory alignment constants:
BLIS_HEAP_STRIDE_ALIGN_SIZE (previously assumed to be same as SYSTEM_MEM)
BLIS_CONTIG_ADDR_ALIGN_SIZE (previously assumed to be same as PAGE_SIZE)
BLIS_STACK_BUF_ALIGN_SIZE (previously not enforced)
and renamed existing ones
BLIS_SYSTEM_MEM_ALIGN_SIZE -> BLIS_HEAP_ADDR_ALIGN_SIZE
BLIS_CONTIG_MEM_ALIGN_SIZE -> BLIS_CONTIG_STRIDE_ALIGN_SIZE
to better convey what the alignment factor is used for (and what it is
not used for).
- Removed BLIS_ENABLE_SYSTEM_MEM_ALIGN. Dynamic memory alignment is now
disabled by setting BLIS_HEAP_STRIDE_ALIGN_SIZE to 1.
- Inserted instances of __attribute__((aligned(BLIS_STACK_BUF_ALIGN_SIZE)))
into macro-kernels to specify stack alignment of temporary buffers.
- Modified test suite driver to output new constants.
- Removed bli_align_dim_to_sys() and bli_align_dim_to_cmem(). Instead, we now
use bli_align_dim_to_size(), which takes a third argument (the desired
alignment).
Details:
- Renamed BLIS_MEMORY_ALIGNMENT_SIZE to BLIS_CONTIG_MEM_ALIGN_SIZE.
- Renamed BLIS_ENABLE_MEMORY_ALIGNMENT to BLIS_ENABLE_SYSTEM_MEM_ALIGN.
- Added BLIS_SYSTEM_MEM_ALIGN_SIZE, which controls only the alignment
passed into posix_memalign() or equivalent.
- Defined new function, bli_align_dim_to_cmem(), which applies the
contiguous memory alignment (rather than the system/malloc alignment).
Details:
- Pass panel strides through bli_align_dim_to_sys() to ensure that each
subsequent packed panel of A and B begins at an aligned address. (The
first panel is presumably aligned to system alignment because it is
aligned to a page boundary, which is typically much larger.)
- Rearranged code in packm_init_pack() to prevent additional conditional
blocks as a result of the aforementioned change.
- Adjusted contiguous memory allocator so that the system memory alignment
is used to allocate enough space for each block no matter what kind of
register blocking is used (even if register blocksize is unit and every
row/column needs maximal padding).
- Adjusted default blocksizes in reference configuration so that MC*KC
and KC*NC result in identical footprints for all datatypes.
Details:
- Changed all filename and function prefixes from 'bl2' to 'bli'.
- Changed the "blis2.h" header filename to "blis.h" and changed all
corresponding #include statements accordingly.
- Fixed incorrect association for Fran in CREDITS file.
