Replace uses of brw_builder::at() with various more descriptive
variants. Use block pointer from instruction when possible.
A couple of special cases remained and will be handled in separate patches.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34681>
Also update WHILE to optionally take a predicate (default to NONE). And
make the predicate in the IF optional (default to NORMAL).
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/34354>
load_reg is something like load_payload except it has a single
source. It copies the entire source to the destination. Its purpose is
to convert a non-SSA VGRF into an SSA value. This copy is marked as
volatile so that it will act as a scheduling barrier.
v2: Fix some typos in the commit message. Eliminate the
brw_builder::LOAD_REG overload that returns a brw_inst*. This is
unlikely to ever be used. Add some checks to brw_validate. All
suggested by Caio.
v3: Force the source and destination types of the LOAD_REG to by
integer. This will (eventually) simplify the creating of unit tests for
the pass that adds LOAD_REG instructions.
Reviewed-by: Caio Oliveira <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/31497>
All remaining uses of that constructor would also use at_end(),
and vice-versa. So just implement that behavior in the constructor
itself.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33815>
And use brw_builder(brw_shader *) and brw_builder() constructors
where possible.
The way tests are written, it is necessary to initialize an "empty"
builder -- which is later replaced by a proper one. Default parameter
NULL make that initialization implicit.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33815>
Since brw_inst now has the block it belongs and the block can
reach the shader, the only necessary information to create a
builder is the brw_inst itself.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33815>
Make the "block after DO" more stable so that adding instructions after
a DO doesn't require repairing the CFG. Use a new SHADER_OPCODE_FLOW
instruction that is a placeholder representing "go to the next block"
and disappears at code generation.
For some context, there are a few facts about how CFG currently works
- Blocks are assumed to not be empty;
- DO is always by itself in a block, i.e. starts and ends a block;
- There are no empty blocks;
- Predicated WHILE and CONTINUE will link to the "block after DO";
- When nesting loops, it is possible that the "block after DO" is
another "DO".
Reasons and further explanations for those are in the brw_cfg.c comments.
What makes this new change useful is that a pass might want to add
instructions between two DO instructions. When that happens, a new
block must be created and any predicated WHILE and CONTINUE must be
repaired.
So, instead of requiring a repair (which has proven to be tricky in
the past), this change adds a block that can be "virtually" empty but
allow instructions to be added without further changes.
One alternative design would be allowing empty blocks, that would be
a deeper change since the blocks are currently assumed to be not empty
in various places. We'll save that for when other changes are made to
the CFG.
The problem described happens in brw_opt_combine_constants, and a
different patch will clean that up.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33536>
Shorter and a preparation to add some functionality to DO().
Had to make it const since that's the convention for builder, so
just made all the sibling helpers const too.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/33536>
