This will replace direct usage of nir_instrs_equal() in the CSE pass,
which reduces an O(n^2) algorithm with an effectively O(n) one. It'll
also be useful for implementing GVN on top of GCM.
v2:
- Add texture support.
- Add more comments.
- Rename instr_can_hash() to instr_can_rewrite() since it's really more
about whether its uses can be rewritten, and it's implicitly used by
nir_instrs_equal() as well.
- Rename nir_instr_set_add() to nir_instr_set_add_or_rewrite() (Jason).
- Make the HASH() macro less magical (Topi).
- Rewrite the commit message.
v3:
- For sorting phi sources, use a VLA, store pointers to the sources, and
compare the predecessor pointer directly (Jason).
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Signed-off-by: Connor Abbott <cwabbott0@gmail.com>
Right now nir_instrs_equal() is tied pretty tightly to CSE, but we're
going to introduce the idea of an instruction set and tie it to that
instead. In anticipation of that, move this into its own file where
we'll add the rest of the instruction set implementation later.
v2: Rebase on texture support.
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Signed-off-by: Connor Abbott <cwabbott0@gmail.com>
Adds nir_src_is_dynamically_uniform which returns true if the source
is known to be dynamically uniform. This will be used in a later patch
to add a workaround for cases that only work with dynamically uniform
sources. Note that the function is not definitive, it can return false
negatives (but not false positives). Currently it only detects
constants and uniform accesses. It could easily be extended to include
more cases.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Previously the name of the nir shader was being freed prematurely during
nir_sweep. Since 756613ed35 the name was later being used to generate
filenames for the optimiser debug output and these would end up with
garbage from the dangling pointer.
Co-authored-by: Neil Roberts <neil@linux.intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
The uniform will only be of a single type so store the data for
opaque types in a single array.
Cc: Francisco Jerez <currojerez@riseup.net>
Cc: Ilia Mirkin <imirkin@alum.mit.edu>
Geometry and tessellation shaders process multiple vertices; their
inputs are arrays indexed by the vertex number. While GLSL makes
this look like a normal array, it can be very different behind the
scenes.
On Intel hardware, all inputs for a particular vertex are stored
together - as if they were grouped into a single struct. This means
that consecutive elements of these top-level arrays are not contiguous.
In fact, they may sometimes be in completely disjoint memory segments.
NIR's existing load_input intrinsics are awkward for this case, as they
distill everything down to a single offset. We'd much rather keep the
vertex ID separate, but build up an offset as normal beyond that.
This patch introduces new nir_intrinsic_load_per_vertex_input
intrinsics to handle this case. They work like ordinary load_input
intrinsics, but have an extra source (src[0]) which represents the
outermost array index.
v2: Rebase on earlier refactors.
v3: Use ssa defs instead of nir_srcs, rebase on earlier refactors.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
get_io_offset() already walks the dereference chain and discovers
whether or not we have an indirect; we can just return that rather than
computing it a second time via deref_has_indirect(). This means moving
the call a bit earlier.
By returning a nir_ssa_def *, we can pass back both an existence flag
(via NULL checking the pointer) and the value in one parameter. It
also simplifies the code somewhat. nir_lower_samplers works in a
similar fashion.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
This is a common enough operation that it's nice to not have to think about
the arguments to foreach_list_typed every time.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Commit 0a1adaf11d (nir: Report progress
from nir_lower_system_values().) introduced a bug caught by Valgrind:
==823== Conditional jump or move depends on uninitialised value(s)
==823== at 0xB09020C: convert_block (nir_lower_system_values.c:68)
==823== by 0xB079FB8: foreach_cf_node (nir.c:1310)
==823== by 0xB07A0AF: nir_foreach_block (nir.c:1336)
==823== by 0xB09026B: convert_impl (nir_lower_system_values.c:79)
...
==823== Uninitialised value was created by a stack allocation
==823== at 0xB090249: convert_impl (nir_lower_system_values.c:76)
which is trivially fixed by initializing progress.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
We may want to use different type_size functions for (e.g.) inputs
vs. uniforms. Passing in -1 for mode ignores this, handling all
modes as before.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
This matches the function signature created in
lower_ubo_reference_visitor::ssbo_store which has a void return.
Suggested-by: Jason Ekstrand <jason@jlekstrand.net>
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
At least on Intel hardware, gl_PrimitiveIDIn comes in as a special part
of the payload rather than a normal input. This is typically what we
use system values for. Dave and Ilia also agree that a system value
would be nicer.
At some point, we should change it at the GLSL IR level as well. But
that requires changing most of the drivers. For now, let's at least
make NIR do the right thing, which is easy.
v2: Add a comment about not creating a temporary (suggested by Iago).
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Iago Toral Quiroga <itoral@igalia.com>
Some hardware (such as Broadwell) can run geometry shaders more
efficiently when the number of vertices emitted is statically known.
This pass provides a way to obtain the constant vertex count, or
-1 indicating that the vertex count is unknown/non-constant.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
The original GLSL IR intrinsics have been lowered to an internal
version that accepts a block index and an offset instead of a
SSBO reference.
v2 (Connor):
- Document the sources used by the atomic intrinsics.
Reviewed-by: Connor Abbott <connor.w.abbott@intel.com>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
This patch moves nir_instr_insert_after_cf_list call into each case
in the intrinsics switch at nir_visitor::visit(ir_call *ir) and
define a nir_dest variable which will be used when handling
ir->return_deref after the switch.
This patch simplifies the code for nir_intrinsic_load_ssbo
implementation changes we are going to do next.
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
v2 (Connor):
- Make the STORE() macro take arguments for the extra sources (and their
size) and any extra indices required.
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
This is how backends provide the buffer size required to compute
the size of unsized arrays in the previous patch
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
This patch also introduces a lowering pass to convert the simple GS
intrinsics to the new ones. See the comments above that for the
rationale behind the new intrinsics.
This should be useful for i965; it's a generic enough mechanism that I
could see other drivers potentially using it as well, so I don't feel
too bad about putting it in the generic code.
v2:
- Use nir_after_block_before_jump for the cursor (caught by Jason
Ekstrand - I'd mistakenly used nir_after_block when rebasing this
code onto the new NIR control flow API).
- Remove the old emit_vertex intrinsic at the end, rather than in
the middle (requested by Jason).
- Use state->... directly rather than locals (requested by Jason).
- Report progress from nir_lower_gs_intrinsics() (requested by me).
- Remove "Authors:" section from file comment (requested by
Michael Schellenberger Costa).
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
The NIR control flow modification API churns the block structure,
splitting blocks, stitching them back together, and so on. Preserving
information about block dominance is hard (and probably not worthwhile).
This patch makes nir_cf_extract() throw away all metadata, like we do
when adding/removing jumps.
We then make the dead control flow pass compute dominance information
right before it uses it. This is necessary because earlier work by the
pass may have invalidated it.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Calling unlink_blocks(block, block->successors[0]) will successfully
unlink the first successor, but then will shift block->successors[1]
down to block->successor[0]. So the successors[1] != NULL check will
always fail.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Consider the case of "while (...) { break }". Or in NIR:
block block_0 (0x7ab640):
...
/* succs: block_1 */
loop {
block block_1:
/* preds: block_0 */
break
/* succs: block_2 */
}
block block_2:
Calling nir_handle_remove_jump(block_1, nir_jump_break) will remove the break.
Unfortunately, it would mangle the predecessors and successors.
Here, block_2->predecessors->entries == 1, so we would create a fake
link, setting block_1->successors[1] = block_2, and adding block_1 to
block_2's predecessor set. This is illegal: a block cannot specify the
same successor twice. In particular, adding the predecessor would have
no effect, as it was already present in the set.
We'd then call unlink_block_successors(), which would delete the fake
link and remove block_1 from block_2's predecessor set. It would then
delete successors[0], and attempt to remove block_1 from block_2's
predecessor set a second time...except that it wouldn't be present,
triggering an assertion failure.
The fix appears to be simple: simply unlink the block's successors and
recreate them to point at the correct blocks first. Then, add the fake
link. In the above example, removing the break would cause block_1 to
have itself as a successor (as it becomes an infinite loop), so adding
the fake link won't cause a duplicate successor.
v2: Add comments (requested by Connor Abbott) and fix commit message.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
There is a bug where we mess up predecessors/successors due to the
ordering of unlinking/recreating edges/adding fake edges. In order to
fix that, I need everything in one routine.
However, calling block_add_normal_succs() isn't safe from
cleanup_cf_node() - it would crash trying to insert phi undefs.
So unfortunately I need to add a parameter.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Consider the following NIR:
block block_0;
/* succs: block_1 block_2 */
if (...) {
block block_1;
...
} else {
block block_2;
}
Calling split_block_beginning() on block_1 would break block_0's
successors: link_block() sets both successors of a block, so calling
link_block(block_0, new_block, NULL) would throw away the second
successor, leaving only /* succ: new_block */. This is invalid: the
block before an if statement must have two successors.
Changing the call to link_block(pred, new_block, pred->successors[0])
would correctly leave both successors in place, but because unlink_block
may shift successor[1] to successor[0], it may not preserve the original
order. NIR maintains a convention that successor[0] must point to the
"then" block, while successor[1] points to the "else" block, so we need
to take care to preserve this ordering.
This patch creates a new function that swaps out one successor for
another, preserving the ordering. It then uses this to fix the issue.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
I need to do this in a second place, and I'd rather make a helper
function than cut and paste the code.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
This is invalid, and causes disasters if we try to unlink successors:
removing the first will work, but removing the second copy will fail
because the block isn't in the successor's predecessor set any longer.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
It's possible that, if a vecN operation is involved in a phi node, that we
could end up moving from a register to itself. If swizzling is involved,
we need to emit the move but. However, if there is no swizzling, then the
mov is a no-op and we might as well not bother emitting it.
Shader-db results on Haswell:
total instructions in shared programs: 6262536 -> 6259558 (-0.05%)
instructions in affected programs: 184780 -> 181802 (-1.61%)
helped: 838
HURT: 0
Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
I don't know of any piglit tests that are currently broken. However, there
is nothing stopping a vecN instruction from getting source modifiers and
lower_vec_to_movs is run after we lower to source modifiers.
Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
We don't use any of the code after the switch anyway. Since we check for
num_components == 1 and early-return, it doesn't get executed so
everything's ok. However, it makes it much clearer what's going on if we
simply do an early return.
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
This was correct but not our usual style.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>