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| author | Pekka Jääskeläinen <visit0r@gcc.gnu.org> | 2018-05-04 19:43:57 +0000 |
|---|---|---|
| committer | Pekka Jääskeläinen <visit0r@gcc.gnu.org> | 2018-05-04 19:43:57 +0000 |
| commit | 080dc24383a602a5a4095eb05b04100f15ba1ad4 (patch) | |
| tree | a0d2a78948f718293527ac76c53bdee3303d989f /gcc/brig/ChangeLog | |
| parent | 1e25c5a9bb7042d7bca5a4fa840666dcb16f4918 (diff) | |
| download | gcc-080dc24383a602a5a4095eb05b04100f15ba1ad4.zip gcc-080dc24383a602a5a4095eb05b04100f15ba1ad4.tar.gz gcc-080dc24383a602a5a4095eb05b04100f15ba1ad4.tar.bz2 | |
[BRIGFE] phsa-specific optimizations
Add flag -fassume-phsa that is on by default. If -fno-assume-phsa
is given, these optimizations are disabled.
With this flag, gccbrig can generate GENERIC that assumes we are
targeting a phsa-runtime based implementation, which allows us
to expose the work-item context accesses to retrieve WI IDs etc.
which helps optimizers.
First optimization that takes advantage of this is to get rid of
the setworkitemid calls whenever we have non-inlined calls that
use IDs internally.
Other optimizations added in this commit:
- expand absoluteid to similar level of simplicity as workitemid.
At the moment absoluteid is the best indexing ID to end up with
WG vectorization.
- propagate ID variables closer to their uses. This is mainly
to avoid known useless casts, which confuse at least scalar
evolution analysis.
- use signed long long for storing IDs. Unsigned integers have
defined wraparound semantics, which confuse at least scalar
evolution analysis, leading to unvectorizable WI loops.
- also refactor some BRIG function generation helpers to brig_function.
- no point in having the wi-loop as a for-loop. It's really
a do...while and SCEV can analyze it just fine still.
- add consts to ptrs etc. in BRIG builtin defs.
Improves optimization opportunities.
- add qualifiers to generated function parameters.
Const and restrict on the hidden local/private pointers,
the arg buffer and the context pointer help some optimizations.
From-SVN: r259957
Diffstat (limited to 'gcc/brig/ChangeLog')
| -rw-r--r-- | gcc/brig/ChangeLog | 43 |
1 files changed, 43 insertions, 0 deletions
diff --git a/gcc/brig/ChangeLog b/gcc/brig/ChangeLog index 7326964..ce4aea6 100644 --- a/gcc/brig/ChangeLog +++ b/gcc/brig/ChangeLog @@ -1,5 +1,48 @@ 2018-05-04 Pekka Jääskeläinen <pekka.jaaskelainen@parmance.com> + Add flag -fassume-phsa that is on by default. If -fno-assume-phsa + is given, these optimizations are disabled. With this flag, gccbrig + can generate GENERIC that assumes we are targeting a phsa-runtime + based implementation, which allows us to expose the work-item context + accesses to retrieve WI IDs etc. which helps optimizers. + First optimization that takes advantage of this is to get rid of + the setworkitemid calls whenever we have non-inlined calls that + use IDs internally. Other optimizations added in this commit: + - expand absoluteid to similar level of simplicity as workitemid. + At the moment absoluteid is the best indexing ID to end up with + WG vectorization. + - propagate ID variables closer to their uses. This is mainly + to avoid known useless casts, which confuse at least scalar + evolution analysis. + - use signed long long for storing IDs. Unsigned integers have + defined wraparound semantics, which confuse at least scalar + evolution analysis, leading to unvectorizable WI loops. + - also refactor some BRIG function generation helpers to brig_function. + - no point in having the wi-loop as a for-loop. It's really + a do...while and SCEV can analyze it just fine still. + - add consts to ptrs etc. in BRIG builtin defs. + Improves optimization opportunities. + - add qualifiers to generated function parameters. + Const and restrict on the hidden local/private pointers, + the arg buffer and the context pointer help some optimizations. + * brig/brigfrontend/brig-basic-inst-handler.cc: See above. + * brig/brigfrontend/brig-branch-inst-handler.cc: See above. + * brig/brigfrontend/brig-cmp-inst-handler.cc: See above. + * brig/brigfrontend/brig-code-entry-handler.cc: See above. + * brig/brigfrontend/brig-code-entry-handler.h: See above. + * brig/brigfrontend/brig-control-handler.cc: See above. + * brig/brigfrontend/brig-cvt-inst-handler.cc: See above. + * brig/brigfrontend/brig-function-handler.cc: See above. + * brig/brigfrontend/brig-function.cc: See above. + * brig/brigfrontend/brig-function.h: See above. + * brig/brigfrontend/brig-label-handler.cc: See above. + * brig/brigfrontend/brig-lane-inst-handler.cc: See above. + * brig/brigfrontend/brig-mem-inst-handler.cc: See above. + * brig/brigfrontend/phsa.h: See above. + * brig/lang.opt: See above. + +2018-05-04 Pekka Jääskeläinen <pekka.jaaskelainen@parmance.com> + * brig/brigfrontend/brig-function-handler.cc: Skip multiple forward declarations of the same function. |