On May 16, 2016 7:29 AM, "Rob Clark" <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> wrote: > > On Sat, May 14, 2016 at 4:03 PM, Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> wrote: > > > > > > On Sat, May 14, 2016 at 12:20 PM, Rob Clark <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> wrote: > >> > >> On Thu, May 12, 2016 at 10:55 PM, Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> > >> wrote: > >> > > >> > > >> > On Tue, May 10, 2016 at 11:57 AM, Rob Clark <<a href="mailto:robdclark@gmail.com">robdclark@gmail.com</a>> wrote: > >> >> > >> >> From: Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> > >> >> > >> >> Some optimizations, like converting integer multiply/divide into left/ > >> >> right shifts, have additional constraints on the search expression. > >> >> Like requiring that a variable is a constant power of two. Support > >> >> these cases by allowing a fxn name to be appended to the search var > >> >> expression (ie. "a#32(is_power_of_two)"). > >> >> > >> >> TODO update doc/comment explaining search var syntax > >> >> TODO the eagle-eyed viewer might have noticed that this could also > >> >> replace the existing const syntax (ie. "#a"). Not sure if we should > >> >> keep that.. we could make it syntactic sugar (ie '#' automatically sets > >> >> the cond fxn ptr to 'is_const') or just get rid of it entirely? Maybe > >> >> that is a follow-on clean-up patch? > >> >> > >> >> Signed-off-by: Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> > >> >> --- > >> >> src/compiler/nir/nir_algebraic.py | 8 +++-- > >> >> src/compiler/nir/nir_opt_algebraic.py | 5 +++ > >> >> src/compiler/nir/nir_search.c | 3 ++ > >> >> src/compiler/nir/nir_search.h | 10 ++++++ > >> >> src/compiler/nir/nir_search_helpers.h | 66 > >> >> +++++++++++++++++++++++++++++++++++ > >> >> 5 files changed, 90 insertions(+), 2 deletions(-) > >> >> create mode 100644 src/compiler/nir/nir_search_helpers.h > >> >> > >> >> diff --git a/src/compiler/nir/nir_algebraic.py > >> >> b/src/compiler/nir/nir_algebraic.py > >> >> index 285f853..19ac6ee 100644 > >> >> --- a/src/compiler/nir/nir_algebraic.py > >> >> +++ b/src/compiler/nir/nir_algebraic.py > >> >> @@ -76,6 +76,7 @@ class Value(object): > >> >> return Constant(val, name_base) > >> >> > >> >> __template = mako.template.Template(""" > >> >> +#include "compiler/nir/nir_search_helpers.h" > >> >> static const ${val.c_type} ${<a href="http://val.name">val.name</a>} = { > >> >> { ${val.type_enum}, ${val.bit_size} }, > >> >> % if isinstance(val, Constant): > >> >> @@ -84,6 +85,7 @@ static const ${val.c_type} ${<a href="http://val.name">val.name</a>} = { > >> >> ${val.index}, /* ${val.var_name} */ > >> >> ${'true' if val.is_constant else 'false'}, > >> >> ${val.type() or 'nir_type_invalid' }, > >> >> + ${val.cond if val.cond else 'NULL'}, > >> >> % elif isinstance(val, Expression): > >> >> ${'true' if val.inexact else 'false'}, > >> >> nir_op_${val.opcode}, > >> >> @@ -113,7 +115,7 @@ static const ${val.c_type} ${<a href="http://val.name">val.name</a>} = { > >> >> Variable=Variable, > >> >> Expression=Expression) > >> >> > >> >> -_constant_re = re.compile(r"(?P<value>[^@]+)(?:@(?P<bits>\d+))?") > >> >> +_constant_re = re.compile(r"(?P<value>[^@$]+)(?:@(?P<bits>\d+))?") > >> > > >> > > >> > Spurious change? > >> > > >> > >> I thought it needed to avoid matching something like > >> a(is_power_of_two).. but it seems to work with that hunk reverted so I > >> guess I can drop it.. > >> > >> >> > >> >> > >> >> class Constant(Value): > >> >> def __init__(self, val, name): > >> >> @@ -150,7 +152,8 @@ class Constant(Value): > >> >> return "nir_type_float" > >> >> > >> >> _var_name_re = re.compile(r"(?P<const>#)?(?P<name>\w+)" > >> >> - > >> >> r"(?:@(?P<type>int|uint|bool|float)?(?P<bits>\d+)?)?") > >> >> + > >> >> r"(?:@(?P<type>int|uint|bool|float)?(?P<bits>\d+)?)?" > >> >> + r"(?P<cond>\([^$]+\))?") > >> >> > >> >> class Variable(Value): > >> >> def __init__(self, val, name, varset): > >> >> @@ -161,6 +164,7 @@ class Variable(Value): > >> >> > >> >> self.var_name = m.group('name') > >> >> self.is_constant = m.group('const') is not None > >> >> + self.cond = m.group('cond') > >> >> self.required_type = m.group('type') > >> >> self.bit_size = int(m.group('bits')) if m.group('bits') else 0 > >> >> > >> >> diff --git a/src/compiler/nir/nir_opt_algebraic.py > >> >> b/src/compiler/nir/nir_opt_algebraic.py > >> >> index 0a95725..952a91a 100644 > >> >> --- a/src/compiler/nir/nir_opt_algebraic.py > >> >> +++ b/src/compiler/nir/nir_opt_algebraic.py > >> >> @@ -62,6 +62,11 @@ d = 'd' > >> >> # constructed value should have that bit-size. > >> >> > >> >> optimizations = [ > >> >> + > >> >> + (('imul', a, '#b@32(is_power_of_two)'), ('ishl', a, ('find_lsb', > >> >> b))), > >> >> + (('udiv', a, '#b@32(is_power_of_two)'), ('ushr', a, ('find_lsb', > >> >> b))), > >> >> + (('umod', a, '#b(is_power_of_two)'), ('iand', a, ('isub', b, > >> >> 1))), > >> >> + > >> >> (('fneg', ('fneg', a)), a), > >> >> (('ineg', ('ineg', a)), a), > >> >> (('fabs', ('fabs', a)), ('fabs', a)), > >> >> diff --git a/src/compiler/nir/nir_search.c > >> >> b/src/compiler/nir/nir_search.c > >> >> index 2c2fd92..b21fb2c 100644 > >> >> --- a/src/compiler/nir/nir_search.c > >> >> +++ b/src/compiler/nir/nir_search.c > >> >> @@ -127,6 +127,9 @@ match_value(const nir_search_value *value, > >> >> nir_alu_instr *instr, unsigned src, > >> >> instr->src[src].src.ssa->parent_instr->type != > >> >> nir_instr_type_load_const) > >> >> return false; > >> >> > >> >> + if (var->cond && !var->cond(instr, src, num_components, > >> >> new_swizzle)) > >> >> + return false; > >> >> + > >> >> if (var->type != nir_type_invalid) { > >> >> if (instr->src[src].src.ssa->parent_instr->type != > >> >> nir_instr_type_alu) > >> >> return false; > >> >> diff --git a/src/compiler/nir/nir_search.h > >> >> b/src/compiler/nir/nir_search.h > >> >> index a500feb..f55d797 100644 > >> >> --- a/src/compiler/nir/nir_search.h > >> >> +++ b/src/compiler/nir/nir_search.h > >> >> @@ -68,6 +68,16 @@ typedef struct { > >> >> * never match anything. > >> >> */ > >> >> nir_alu_type type; > >> >> + > >> >> + /** Optional condition fxn ptr > >> >> + * > >> >> + * This is only allowed in search expressions, and allows > >> >> additional > >> >> + * constraints to be placed on the match. Typically used for > >> >> 'is_constant' > >> >> + * variables to require, for example, power-of-two in order for the > >> >> search > >> >> + * to match. > >> >> + */ > >> >> + bool (*cond)(nir_alu_instr *instr, unsigned src, > >> >> + unsigned num_components, const uint8_t *swizzle); > >> >> } nir_search_variable; > >> >> > >> >> typedef struct { > >> >> diff --git a/src/compiler/nir/nir_search_helpers.h > >> >> b/src/compiler/nir/nir_search_helpers.h > >> >> new file mode 100644 > >> >> index 0000000..8ed2ca0 > >> >> --- /dev/null > >> >> +++ b/src/compiler/nir/nir_search_helpers.h > >> >> @@ -0,0 +1,66 @@ > >> >> +/* > >> >> + * Copyright © 2016 Red Hat > >> >> + * > >> >> + * Permission is hereby granted, free of charge, to any person > >> >> obtaining > >> >> a > >> >> + * copy of this software and associated documentation files (the > >> >> "Software"), > >> >> + * to deal in the Software without restriction, including without > >> >> limitation > >> >> + * the rights to use, copy, modify, merge, publish, distribute, > >> >> sublicense, > >> >> + * and/or sell copies of the Software, and to permit persons to whom > >> >> the > >> >> + * Software is furnished to do so, subject to the following > >> >> conditions: > >> >> + * > >> >> + * The above copyright notice and this permission notice (including > >> >> the > >> >> next > >> >> + * paragraph) shall be included in all copies or substantial portions > >> >> of > >> >> the > >> >> + * Software. > >> >> + * > >> >> + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, > >> >> EXPRESS OR > >> >> + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF > >> >> MERCHANTABILITY, > >> >> + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT > >> >> SHALL > >> >> + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES > >> >> OR > >> >> OTHER > >> >> + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, > >> >> ARISING > >> >> + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER > >> >> DEALINGS > >> >> + * IN THE SOFTWARE. > >> >> + * > >> >> + * Authors: > >> >> + * Rob Clark <<a href="mailto:robclark@freedesktop.org">robclark@freedesktop.org</a>> > >> >> + */ > >> >> + > >> >> +#ifndef _NIR_SEARCH_HELPERS_ > >> >> +#define _NIR_SEARCH_HELPERS_ > >> >> + > >> >> +#include "nir.h" > >> >> + > >> >> +static inline bool > >> >> +__is_power_of_two(unsigned int x) > >> >> +{ > >> >> + return ((x != 0) && !(x & (x - 1))); > >> >> +} > >> >> + > >> >> +static inline bool > >> >> +is_power_of_two(nir_alu_instr *instr, unsigned src, unsigned > >> >> num_components, > >> >> + const uint8_t *swizzle) > >> >> +{ > >> >> + nir_const_value *val = nir_src_as_const_value(instr->src[src].src); > >> >> + > >> >> + /* only constant src's: */ > >> >> + if (!val) > >> >> + return false; > >> >> + > >> >> + for (unsigned i = 0; i < num_components; i++) { > >> >> + switch (nir_op_infos[instr->op].input_types[src]) { > >> >> + case nir_type_int: > >> >> + if (!__is_power_of_two(val->i32[swizzle[i]])) > >> >> + return false; > >> >> + break; > >> >> + case nir_type_uint: > >> >> + if (!__is_power_of_two(val->u32[swizzle[i]])) > >> >> + return false; > >> > > >> > > >> > Your implementation of __is_power_of_two takes an unsigned. There's no > >> > benefit to splitting it into two cases and it just creates a false > >> > distinction. If you do, you can probably inline the helper (I don't > >> > care > >> > much one way or the other on that). > >> > >> hmm, are you sure about negative PoT? Although possibly that should > >> be '__is_power_of_two(ABS(val->i32[..])'? > > > > > > I don't know off-hand whether or not it's correct for negative power-of-two. > > However, I do know that it does exactly the same thing in both cases > > regardless of whether or not the first one is correct :-) > > --Jason > > so, for the record, __is_power_of_two(ABS(val->i32[..])) seems to be > the correct thing to do. That would let us add a (presumably > optional) rule to lower idiv to ushr plus a multiply by the isign of > each of the args.. Unfortunately, idiv can never be lowered because -1 >> 1 == -1. Yeah, that's annoying. Also, I don't think any of the optimizations you've added here works for negative numbers without a sign-flip. We would need a pair of optimizations: one for non-negative powers of two and one for negative. > BR, > -R > > >> > >> BR, > >> -R > >> > >> > All in all, this seems ok. The "(some_function)" syntax seems clunky > >> > but I > >> > can't come up with anything better off-hand. Let's just go with it for > >> > now > >> > and we can always change it later. > >> > > >> > Reviewed-by: Jason Ekstrand <<a href="mailto:jason@jlekstrand.net">jason@jlekstrand.net</a>> > >> > > >> >> > >> >> + break; > >> >> + default: > >> >> + return false; > >> >> + } > >> >> + } > >> >> + > >> >> + return true; > >> >> +} > >> >> + > >> >> +#endif /* _NIR_SEARCH_ */ > >> >> -- > >> >> 2.5.5 > >> >> > >> > > > > >