In the fully general case of register classes, to expose an allocation
class of unaligned 2-contiguous-regs allocations, for example, you'd have
your base individual regs (128 on intel), and another set of 127 regs that
each conflicted with the corresponding pair of the base regs. Single-reg
nodes would allocate in the 128, and double-reg nodes would allocate in
the 127 and the user would remap from the 127 down to the base regs with
some irritating table.
If you need many different contiguous allocation sizes (16 is a pretty
common number across drivers), your number of regs explodes, wasting
memory and making the q computation expensive at startup.
If all the user has is contiguous-reg classes, we can easily compute the q
value up front (as found in the intel driver and nouveau, for example),
and we only have to change a couple of places in the conflict-checking
logic so the contiguous-reg classes can use the base registers.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/9437>
In the select_reg callback, I want to be able to determine if a given
node is already assigned, and if so what physical register has been
assigned.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4071>
Add a parameter so the callback can know which node it is selecting a
register for. And remove the graph parameter, as it is unused by
existing users, and somewhat unnecessary (ie. the callback data could
be used instead).
And add a comment so $future_me remembers how this works.
Signed-off-by: Rob Clark <robdclark@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4071>
Setting up transitive conflicts between a full register and its two
half registers (eg r0.x and hr0.x and hr0.y) will make the half
registers conflict. They don't actually conflict and this prevents us
from using both at the same time.
Add and use a new ra helper that sets up transitive conflicts between
a register and its subregisters, except it carefully avoids the
subregister conflict.
Signed-off-by: Kristian H. Kristensen <hoegsberg@google.com>
Reviewed-by: Rob Clark <robdclark@chromium.org>
Complements the existing getters and the setter for node class. To be
used in the Panfrost RA refactor.
Signed-off-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
VC4 has had a tension, similar to pre-Sandybridge Intel, where we want to
use low-numbered registers (more parallelism on Intel, fewer delay slots
on vc4), but in order to give instruction scheduling the most freedom to
avoid delays we want to round-robin between registers of the same cost.
Our two heuristics so far have chosen one end or the other of that
tradeoff.
The callback, instead, hands the driver the set of registers that are
available, and the driver gets to make its own choice. This will be used
in vc4 to round-robin between registers of the same cost, and might be
used in the future for improving bank selection.
Reviewed-by: Nicolai Hähnle <nicolai.haehnle@amd.com>
Since i965 is now using make_reg_conflicts_transitive and doesn't need
q-value computations, they are disabled on i965. They are enabled
everywhere else so that they get the old behavior. This reduces the time
spent in eglInitialize() on BDW by around 10-15%.
Reviewed-by: Eric Anholt <eric@anholt.net>
System headers may contain C++ declarations, which cannot be given C
linkage. For this reason, include statements should never occur
inside extern "C".
This patch moves the C linkage statements to enclose only the
declarations within a single header.
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>
The r300 gallium driver is using it outside of the Mesa tree, and I wanted
to do so for vc4 as well. Rather than make the multiple-definitions
problem even more complicated, just move it to more-shared code.
v2: Don't forget to delete the symlink in r300 (review by Matt).
Delete more r300-helper references (review by Emil)
Don't prefix util/ header inclusion with "util/" (review by Emil)
Reviewed-by: Matt Turner <mattst88@gmail.com> (v1)
Reviewed-by: Emil Velikov <emil.l.velikov@gmail.com> (v1)
2014-09-23 13:40:10 -07:00
Renamed from src/mesa/program/register_allocate.h (Browse further)
Eric Anholt
Jason Ekstrand
Rob Clark
Kristian H. Kristensen
Alyssa Rosenzweig
Emil Velikov
Jason Ekstrand
Mark Janes