Generalize the code for remove dead loops to also remove dead if
nodes. The conditions are the same in both cases, if the node (and
it's children) don't have side-effects AND the nodes after it don't
use the values produced by the node.
The only difference is when evaluating side effects: loops consider
only return jumps as a side-effect -- they can stop execution of nodes
after it; 'if' nodes outside loops should consider all kinds of
jumps (return, break, continue) since all of them can cause execution
of nodes after it to be skipped.
After this patch, empty ifs (those which both then and else blocks are
empty) will be removed by nir_opt_dead_cf.
It caused no change to shader-db, in part because the removal of empty
ifs is currently covered by nir_opt_peephole_select.
v2: Improve the identification of cases where break/continue can cause
side-effects. (Jason)
v3: Move code comment changes to a different patch. (Jason)
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
One of NIR's invariants is that control flow lists always start and end
with blocks. There's no good reason why we should return a cf_node from
these functions since we know that it's always a block. Making it a block
lets us remove a bunch of code.
Signed-off-by: Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Clean up misrepetitions ('if if', 'the the' etc) found throughout the
comments. This has been done manually, after grepping
case-insensitively for duplicate if, is, the, then, do, for, an,
plus a few other typos corrected in fly-by
v2:
* proper commit message and non-joke title;
* replace two 'as is' followed by 'is' to 'as-is'.
v3:
* 'a integer' => 'an integer' and similar (originally spotted by
Jason Ekstrand, I fixed a few other similar ones while at it)
Signed-off-by: Giuseppe Bilotta <giuseppe.bilotta@gmail.com>
Reviewed-by: Chad Versace <chad.versace@intel.com>
Parenthesis are needed here as ! takes precedence over the &. The
check had the opposite effect than intended.
Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
This matches the "foreach x in container" pattern found in many other
programming languages. Generated by the following regular expression:
s/nir_foreach_function(\([^,]*\),\s*\([^,]*\))/nir_foreach_function(\2, \1)/
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
This matches the "foreach x in container" pattern found in many other
programming languages. Generated by the following regular expression:
s/nir_foreach_phi_src(\([^,]*\),\s*\([^,]*\))/nir_foreach_phi_src(\2, \1)/
and a similar expression for nir_foreach_phi_src_safe.
Reviewed-by: Eduardo Lima Mitev <elima@igalia.com>
This matches the "foreach x in container" pattern found in many other
programming languages. Generated by the following regular expression:
s/nir_foreach_instr(\([^,]*\),\s*\([^,]*\))/nir_foreach_instr(\2, \1)/
and similar expressions for nir_foreach_instr_safe etc.
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
