On Fri, Mar 20, 2015 at 2:23 PM, Jason Ekstrand <ja...@jlekstrand.net> wrote: > v2: Fix the spelling of analyze and re-arrange code for better readability > as per Connor's comments. > v3: Make the naming of things more consistent and add a pile of comments > --- > src/mesa/drivers/dri/i965/Makefile.sources | 2 + > src/mesa/drivers/dri/i965/brw_nir.h | 78 ++++++ > .../dri/i965/brw_nir_analyze_boolean_resolves.c | 275 > +++++++++++++++++++++ > 3 files changed, 355 insertions(+) > create mode 100644 src/mesa/drivers/dri/i965/brw_nir.h > create mode 100644 > src/mesa/drivers/dri/i965/brw_nir_analyze_boolean_resolves.c > > diff --git a/src/mesa/drivers/dri/i965/Makefile.sources > b/src/mesa/drivers/dri/i965/Makefile.sources > index c69441b..3a3df70 100644 > --- a/src/mesa/drivers/dri/i965/Makefile.sources > +++ b/src/mesa/drivers/dri/i965/Makefile.sources > @@ -73,6 +73,8 @@ i965_FILES = \ > brw_meta_util.h \ > brw_misc_state.c \ > brw_multisample_state.h \ > + brw_nir.h \ > + brw_nir_analyze_boolean_resolves.c \ > brw_object_purgeable.c \ > brw_packed_float.c \ > brw_performance_monitor.c \ > diff --git a/src/mesa/drivers/dri/i965/brw_nir.h > b/src/mesa/drivers/dri/i965/brw_nir.h > new file mode 100644 > index 0000000..27782a3 > --- /dev/null > +++ b/src/mesa/drivers/dri/i965/brw_nir.h > @@ -0,0 +1,78 @@ > +/* > + * Copyright © 2015 Intel Corporation > + * > + * 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. > + */ > + > +#pragma once > + > +#include "glsl/nir/nir.h" > + > +#ifdef __cplusplus > +extern "C" { > +#endif > + > +/* Flags set in the instr->pass_flags field by i965 analysis passes */ > +enum { > + BRW_NIR_NON_BOOLEAN = 0x0, > + > + /* Indicates that the given instruction's destination is a boolean > + * value but that it needs to be resolved before it can be used. > + * On Gen <= 5, CMP instructions return a 32-bit value where the bottom > + * bit represents the actual true/false value of the compare and the top > + * 31 bits are undefined. In order to use this value, we have to do a > + * "resolve" operation by replacing the value of the CMP with -(x & 1) > + * to sign-extend the bottom bit to 0/~0. > + */ > + BRW_NIR_BOOLEAN_NEEDS_RESOLVE = 0x1, > + > + /* Indicates that the given instruction's destination is a boolean > + * value that has intentionally been left unresolved. Not all boolean > + * values need to be resolved immediately. For instance, if we have > + * > + * CMP r1 r2 r3 > + * CMP r4 r5 r6 > + * AND r7 r1 r4 > + * > + * We don't have to resolve the result of the two CMP instructions > + * immediately because the AND still does an AND of the bottom bits. > + * Instead, we can save ourselves instructions by delaying the resolve > + * until after the AND. The result of the two CMP instructions is left > + * as BRW_NIR_BOOLEAN_UNRESOLVED. > + */ > + BRW_NIR_BOOLEAN_UNRESOLVED = 0x2, > + > + /* Indicates a that the given instruction's destination is a boolean > + * value that does not need a resolve. For instance, if you AND two > + * values that are BRW_NIR_BOOLEAN_NEEDS_RESOLVE then we know that both
Ah, I misunderstood this comment on first read. You're saying that the two things marked as NEEDS_RESOLVE will be resolved before the AND consumes them, ... so the AND's destination will be marked with NO_RESOLVE? That makes sense. > + * values will be 0/~0 before we get them and the result of the AND is > + * also guaranteed to be 0/~0 and does not need a resolve. > + */ > + BRW_NIR_BOOLEAN_NO_RESOLVE = 0x3, > + > + /* A mask to mask the boolean status values off of instr->pass_flags */ > + BRW_NIR_BOOLEAN_MASK = 0x3, > +}; > + > +void brw_nir_analyze_boolean_resolves(nir_shader *nir); > + > +#ifdef __cplusplus > +} > +#endif > diff --git a/src/mesa/drivers/dri/i965/brw_nir_analyze_boolean_resolves.c > b/src/mesa/drivers/dri/i965/brw_nir_analyze_boolean_resolves.c > new file mode 100644 > index 0000000..e893a65 > --- /dev/null > +++ b/src/mesa/drivers/dri/i965/brw_nir_analyze_boolean_resolves.c > @@ -0,0 +1,275 @@ > +/* > + * Copyright © 2015 Intel Corporation > + * > + * 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: > + * Jason Ekstrand <ja...@jlekstrand.net> > + */ > + > +#include "brw_nir.h" > + > +/* > + * This file implements an analysis pass that determines when we have to do > + * a boolean resolve on Gen <= 5. Instructions that need a boolean resolve > + * will have the booleans portion of the instr->pass_flags field set to > + * BRW_NIR_BOOLEAN_NEEDS_RESOLVE. > + */ > + > + > +/** Returns the resolve status for the given source > + * > + * If the source has a parent instruction then the resolve status is the > + * status of the parent instruction. If the source does not have a parent > + * instruction then we don't know so we return NON_BOOLEAN. > + */ > +static uint8_t > +get_resolve_status_for_src(nir_src *src) > +{ > + nir_instr *src_instr; > + if (src->is_ssa) { > + src_instr = src->ssa->parent_instr; > + } else { > + src_instr = src->reg.reg->parent_instr; > + } > + > + if (src_instr) { > + uint8_t resolve_status = src_instr->pass_flags & BRW_NIR_BOOLEAN_MASK; > + > + /* If the source instruction needs resolve, then from the perspective > + * of the user, it's a true boolean. > + */ > + if (resolve_status == BRW_NIR_BOOLEAN_NEEDS_RESOLVE) > + resolve_status = BRW_NIR_BOOLEAN_NO_RESOLVE; > + return resolve_status; > + } else { > + return BRW_NIR_NON_BOOLEAN; > + } > +} > + > +/** Marks the given source as needing a resolve > + * > + * If the given source corresponds to an unresolved boolean it marks it as > + * needing a resolve. Otherwise, we leave it alone. > + */ > +static bool > +src_mark_needs_resolve(nir_src *src, void *void_state) > +{ > + nir_instr *src_instr; > + if (src->is_ssa) { > + src_instr = src->ssa->parent_instr; > + } else { > + src_instr = src->reg.reg->parent_instr; > + } > + > + if (src_instr) { > + uint8_t resolve_status = src_instr->pass_flags & BRW_NIR_BOOLEAN_MASK; > + > + /* If the source instruction is unresolved, then mark it as needing > + * to be resolved. > + */ > + if (resolve_status == BRW_NIR_BOOLEAN_UNRESOLVED) { > + src_instr->pass_flags &= ~BRW_NIR_BOOLEAN_MASK; > + src_instr->pass_flags |= BRW_NIR_BOOLEAN_NEEDS_RESOLVE; > + } > + > + } > + > + return true; > +} > + > +static bool > +analyze_boolean_resolves_block(nir_block *block, void *void_state) > +{ > + nir_foreach_instr(block, instr) { > + switch (instr->type) { > + case nir_instr_type_alu: { > + /* For ALU instructions, the resolve status is handled in a > + * three-step process. > + * > + * 1) Look at the instruction type and sources and determine if it > + * can be left unresolved. > + * > + * 2) Look at the destination and see if we have to resolve > + * anyway. (This is the case if this instruction is not the > + * only instruction writing to a given register.) > + * > + * 3) If the instruction has a resolve status other than > + * BOOL_UNRESOLVED or BOOL_NEEDS_RESOLVE then we walk through > + * the sources and ensure that they are also resolved. This > + * ensures that we don't end up with any stray unresolved > + * booleans going into ADDs or something like that. > + */ > + > + uint8_t resolve_status; > + nir_alu_instr *alu = nir_instr_as_alu(instr); > + switch (alu->op) { > + case nir_op_flt: > + case nir_op_ilt: > + case nir_op_ult: > + case nir_op_fge: > + case nir_op_ige: > + case nir_op_uge: > + case nir_op_feq: > + case nir_op_ieq: > + case nir_op_fne: > + case nir_op_ine: > + case nir_op_f2b: > + case nir_op_i2b: > + /* This instruction will turn into a CMP when we actually emit > + * so the result will have to be resolved before it can be used. > + */ > + resolve_status = BRW_NIR_BOOLEAN_UNRESOLVED; > + > + /* Even though the destination is allowed to be left unresolved, > + * the sources are treated as regular integers or floats so > + * they need to be resolved. > + */ > + nir_foreach_src(instr, src_mark_needs_resolve, NULL); > + break; > + > + case nir_op_imov: > + case nir_op_inot: > + if (alu->dest.write_mask == 1) { > + /* This is a single-source instruction. Just copy the > + * resolve status from the source. > + */ > + resolve_status = get_resolve_status_for_src(&alu->src[0].src); > + } else { > + /* Vector versions will be assumed to be non-boolean. */ > + resolve_status = BRW_NIR_NON_BOOLEAN; I've got some patches to allow ir_unop_logic_not (and and, or, xor) to operate per-component. That's not related to this comment though, right? As far as I can tell this looks good. It'd be cool if Connor could confirm. Reviewed-by: Matt Turner <matts...@gmail.com> _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev