We already don't convert constants out of SSA, and in our backend we'd
like to have only one way of saying something is still in SSA.
The one tricky part about this is that we may now leave some undef
instructions around if they aren't part of a phi-web, so we have to be
more careful about deleting them.
v2: rename and flip meaning of flag (Jason)
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
This commit switches us from the current setup of using hash sets for
use/def sets to using linked lists. Doing so should save us quite a bit of
memory because we aren't carrying around 3 hash sets per register and 2 per
SSA value. It should also save us CPU time because adding/removing things
from use/def sets is 4 pointer manipulations instead of a hash lookup.
Running shader-db 50 times with USE_NIR=0, NIR, and NIR + use/def lists:
GLSL IR Only: 586.4 +/- 1.653833
NIR with hash sets: 675.4 +/- 2.502108
NIR + use/def lists: 641.2 +/- 1.557043
I also ran a memory usage experiment with Ken's patch to delete GLSL IR and
keep NIR. This patch cuts an aditional 42.9 MiB of ralloc'd memory over
and above what we gained by deleting the GLSL IR on the same dota trace.
On the code complexity side of things, some things are now much easier and
others are a bit harder. One of the operations we perform constantly in
optimization passes is to replace one source with another. Due to the fact
that an instruction can use the same SSA value multiple times, we had to
iterate through the sources of the instruction and determine if the use we
were replacing was the only one before removing it from the set of uses.
With this patch, uses are per-source not per-instruction so we can just
remove it safely. On the other hand, trying to iterate over all of the
instructions that use a given value is more difficult. Fortunately, the
two places we do that are the ffma peephole where it doesn't matter and GCM
where we already gracefully handle duplicates visits to an instruction.
Another aspect here is that using linked lists in this way can be tricky to
get right. With sets, things were quite forgiving and the worst that
happened if you didn't properly remove a use was that it would get caught
in the validator. With linked lists, it can lead to linked list corruption
which can be harder to track. However, we do just as much validation of
the linked lists as we did of the sets so the validator should still catch
these problems. While working on this series, the vast majority of the
bugs I had to fix were caught by assertions. I don't think the lists are
going to be that much worse than the sets.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Storing this here is pretty sketchy - I don't know if any driver other
than i965 will want to use it. But this will make it a lot easier to
generate NIR code at link time. We'll probably rework it anyway.
(Ian suggested making nir_assign_var_locations_scalar_direct_first
simply modify the nir_shader's fields, rather than passing pointers
to them. If this stays long term, we should do that. But Jason and
I suspect we'll be reworking this area again in the near future.)
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Originally you had to have one or the other. But actually I don't want
either. (Or rather I want whatever is the minimum # of instructions.)
TODO: not sure where the best place to insert a check that driver hasn't
set *both* lower_negate and lower_sub?
Signed-off-by: Rob Clark <robclark@freedesktop.org>
We don't actually need a gl_program struct. We only used it to
translate prog->Target (i.e. GL_VERTEX_PROGRAM) to the gl_shader_stage
(i.e. MESA_SHADER_VERTEX). We may as well just pass that.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
I want to use this in some code that doesn't currently include mtypes.h.
It seems like a better place for it anyway.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
This pass performs a mark and sweep pass over a nir_shader's associated
memory - anything still connected to the program will be kept, and any
dead memory we dropped on the floor will be freed.
The expectation is that this will be called when finished building and
optimizing the shader. However, it's also fine to call it earlier, and
many times, to free up memory earlier.
v2: (feedback from Jason Ekstrand)
- Skip sweeping impl->start_block, as it's already in the CF list.
- Don't sweep SSA defs (they're owned by their defining instruction)
- Don't steal phi sources (they're owned by nir_phi_instr).
- Don't steal tex->src (it's owned by the tex_inst itself)
- Don't sweep dereference chains (top-level dereferences are owned by
the instruction; sub-dereferences are owned by the parent deref).
- Don't sweep sources and destinations (SSA defs are handled as part of
the defining instruction, and registers are handled as part of
function implementations).
- Just steal instructions; don't walk them (no longer required).
v3: (feedback from Jason Ekstrand)
- Steal indirect sources from nir_src/nir_dest.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Based on the algo from NV50LegalizeSSA::handleDIV() and handleMOD().
See also trans_idiv() in freedreno/ir3/ir3_compiler.c (which was an
adaptation of the nv50 code from Ilia Mirkin).
A python/numpy script which implements the same algorithm (and is
possibly useful for debugging or analysis) can be found here:
http://people.freedesktop.org/~robclark/div-lowering.py
I've tested this on i965 hacked up to insert the idiv lowering pass,
and on freedreno with NIR frontend.
Signed-off-by: Rob Clark <robclark@freedesktop.org>
Tested-by: Eric Anholt <eric@anholt.net> (vc4)
In freedreno these get implemented as the matching f* instruction plus a
u2f to convert the result to float 1.0/0.0. But less lines of code to
just let nir_opt_algebraic handle this for us, plus opens up some small
window for other opt passes to improve (ie. if some shader ended up with
both a flt and slt with same src args, for example).
v2: use b2f rather than u2f
Signed-off-by: Rob Clark <robclark@freedesktop.org>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
This commit adds a pass to L1-normalize cube-map coordinates. Some hardware
such as i965 requires that largest cube-map coordinate is +-1. We had a
pass to perform this normalization in GLSL IR but we need it in NIR for
cube maps on ARB programs to work correctly.
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>
v2 (Suggested by Eric):
- Do a vector fabs and split into components later
- Move to core NIR
Reviewed-by: Eric Anholt <eric@anholt.net>
Not much hardware wants them these days, and it might give us a chance to
do CSE or algebraic at the NIR level.
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
v2: Delete the set of indirectly accessed variables when we're done with it
v3: Rename from _packed to _scalar
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Previously, we just assigned variable locations in nir_lower_io. Now, we
force the user to assign variable locations for us. This gives the backend
a bit more control over where variables are placed.
v2: Rename from _packed to _scalar
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
We never did a single hash table lookup in the entire NIR code base that I
found so there was no real benifit to doing it that way. I suppose that
for linking, we'll probably want to be able to lookup by name but we can
leave building that hash table to the linker. In the mean time this was
causing problems with GLSL IR -> NIR because GLSL IR doesn't guarantee us
unique names of uniforms, etc. This was causing massive rendering isues in
the unreal4 Sun Temple demo.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
glsl_to_nir, tgsi_to_nir, and prog_to_nir all want to know whether the
driver supports native integers. Presumably other passes may as well.
Adding this to nir_shader_compiler_options is an easy way to provide
that information, as it's accessible via nir_shader::options.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Nothing actually uses these, and the only caller of glsl_to_nir()
(brw_fs_nir.cpp) always passes NULL for the _mesa_glsl_parse_state
pointer, meaning they'll always be NULL and 0, respectively.
Just delete them.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
This adds a parent_instr field similar to the one for ssa_def. The
difference here is that the parent_instr field on a nir_register can be
NULL if the register does not have a unique definition or if that
definition does not dominate all its uses. We set this field in the
out-of-SSA pass so that backends can get SSA-like information even after
they have gone out of SSA.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
One less new directory necessary for gallium code that wants to interact
with NIR.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>
v2 Jason Ekstrand <jason.ekstrand@intel.com>:
- Use nir_dominance_lca for computing least common anscestors
- Use the block index for comparing dominance tree depths
- Pin things that do partial derivatives
Reviewed-by: Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
This is mostly thanks to Connor. The idea is to do a depth-first search
that computes pre and post indices for all the blocks. We can then figure
out if one block dominates another in constant time by two simple
comparison operations.
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Being able to find the least common anscestor in the dominance tree is a
useful thing that we may want to do in other passes. In particular, we
need it for GCM.
v2: Handle NULL inputs by returning the other block
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Mesa has a shader compiler struct flagging whether GLSL IR's opt_algebraic
and other passes should try and generate certain types of opcodes or
patterns. Extend that to NIR by defining our own struct, which is
automatically generated from the Mesa struct in glsl_to_nir and provided
directly by the driver in TGSI-to-NIR.
v2: Split out the previous two prep patches.
v3: Rebase to master (no TGSI->NIR present)
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> (v2)
This will be used to give the optimization passes a chance to customize
behavior for the particular target device.
v2: Rebase to master (no TGSI->NIR present)
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org> (v1)
Printing instructions doesn't modify them, so we can mark the parameter
const.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
v2 Jason Ekstrand <jason.ekstrand@intel.com>:
- Add better comments
- Use nir_ssa_dest_init and nir_src_for_ssa more places
- Fix some void * casts
v3 Jason Ekstrand <jason.ekstrand@intel.com>:
- Rework the way we determine whether or not to sccalarize a phi node to
make the recursion non-bogus
- Treat load_const instructions as scalarizable
v4 Jason Ekstrand <jason.ekstrand@intel.com>:
- Allow uniform and input loads to be scalarizable
v5 Jason Ekstrand <jason.ekstrand@intel.com>:
- Also consider loads of inputs (varying, uniform, or ubo) to be
scalarizable. We were already doing this for load_var on uniforms and
inputs.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Unlike with non-SSA ALU instructions, where if they're per-component
you have to look at the writemask to know which source channels are
being used, SSA ALU instructions always have all the possible channels
enabled so we can just look at the number of components in the SSA
definition for per-component instructions to say how many source
components are being used.
v2: use new name nir_ssa_alu_instr_src_components()
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
Signed-off-by: Connor Abbott <cwabbott0@gmail.com>
This avoids the overhead of copying structures and better matches the newly
added nir_alu_src_copy and nir_alu_dest_copy.
Reviewed-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Before, we used a system where a file, nir_opcodes.h, defined some macros that
were included to generate the enum values and the nir_op_infos structure. This
worked pretty well, but for development the error messages were never very
useful, Python tools couldn't understand the opcode list, and it was difficult
to use nir_opcodes.h to do other things like autogenerate a builder API. Now, we
store opcode information in nir_opcodes.py, and we have nir_opcodes_c.py to
generate the old nir_opcodes.c and nir_opcodes_h.py to generate nir_opcodes.h,
which contains all the enum names and gets included into nir.h like before. In
addition to solving the above problems, using Python and Mako to generate
everything means that it's much easier to add keep information centralized as we
add new things like constant propagation that require per-opcode information.
v2:
- make Opcode derive from object (Dylan)
- don't use assert like it's a function (Dylan)
- style fixes for fnoise, use xrange (Dylan)
- use iterkeys() in nir_opcodes_h.py (Dylan)
- use pydoc-style comments (Jason)
- don't make fmin/fmax commutative and associative yet (Jason)
Signed-off-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
v3 Jason Ekstrand <jason.ekstrand@intel.com>
- Alphabetize source file lists
- Generate nir_opcodes.h in the builddir instead of the source dir
- Include $(builddir)/src/glsl/nir in the i965 build
- Rework nir_opcodes.h generation so it generates a complete header file
instead of one that has to be embedded inside an enum declaration
Connor Abbott