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authorJason Ekstrand <[email protected]>2017-02-28 09:10:43 -0800
committerEmil Velikov <[email protected]>2017-03-13 11:16:34 +0000
commit700bebb958e93f4d472c383de62ced9db8e64bec (patch)
tree0075c098c56c338f38ba0db80b9dba3e7e268a17 /src/intel/compiler/brw_nir_analyze_boolean_resolves.c
parentd0d4a5f43b4dd79bd7bfff7c7deaade10bfebf7c (diff)
i965: Move the back-end compiler to src/intel/compiler
Mostly a dummy git mv with a couple of noticable parts: - With the earlier header cleanups, nothing in src/intel depends files from src/mesa/drivers/dri/i965/ - Both Autoconf and Android builds are addressed. Thanks to Mauro and Tapani for the fixups in the latter - brw_util.[ch] is not really compiler specific, so it's moved to i965. v2: - move brw_eu_defines.h instead of brw_defines.h - remove no-longer applicable includes - add missing vulkan/ prefix in the Android build (thanks Tapani) v3: - don't list brw_defines.h in src/intel/Makefile.sources (Jason) - rebase on top of the oa patches [Emil Velikov: commit message, various small fixes througout] Signed-off-by: Emil Velikov <[email protected]> Reviewed-by: Jason Ekstrand <[email protected]>
Diffstat (limited to 'src/intel/compiler/brw_nir_analyze_boolean_resolves.c')
-rw-r--r--src/intel/compiler/brw_nir_analyze_boolean_resolves.c269
1 files changed, 269 insertions, 0 deletions
diff --git a/src/intel/compiler/brw_nir_analyze_boolean_resolves.c b/src/intel/compiler/brw_nir_analyze_boolean_resolves.c
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index 00000000000..4ad26e21103
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+++ b/src/intel/compiler/brw_nir_analyze_boolean_resolves.c
@@ -0,0 +1,269 @@
+/*
+ * 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 <[email protected]>
+ */
+
+#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)
+{
+ if (src->is_ssa) {
+ nir_instr *src_instr = src->ssa->parent_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)
+{
+ if (src->is_ssa) {
+ nir_instr *src_instr = src->ssa->parent_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)
+{
+ nir_foreach_instr(instr, block) {
+ 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_ball_fequal2:
+ case nir_op_ball_iequal2:
+ case nir_op_ball_fequal3:
+ case nir_op_ball_iequal3:
+ case nir_op_ball_fequal4:
+ case nir_op_ball_iequal4:
+ case nir_op_bany_fnequal2:
+ case nir_op_bany_inequal2:
+ case nir_op_bany_fnequal3:
+ case nir_op_bany_inequal3:
+ case nir_op_bany_fnequal4:
+ case nir_op_bany_inequal4:
+ /* These are only implemented by the vec4 backend and its
+ * implementation emits resolved booleans. At some point in the
+ * future, this may change and we'll have to remove some of the
+ * above cases.
+ */
+ resolve_status = BRW_NIR_BOOLEAN_NO_RESOLVE;
+ break;
+
+ case nir_op_imov:
+ case nir_op_inot:
+ /* 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);
+ break;
+
+ case nir_op_iand:
+ case nir_op_ior:
+ case nir_op_ixor: {
+ uint8_t src0_status = get_resolve_status_for_src(&alu->src[0].src);
+ uint8_t src1_status = get_resolve_status_for_src(&alu->src[1].src);
+
+ if (src0_status == src1_status) {
+ resolve_status = src0_status;
+ } else if (src0_status == BRW_NIR_NON_BOOLEAN ||
+ src1_status == BRW_NIR_NON_BOOLEAN) {
+ /* If one of the sources is a non-boolean then the whole
+ * thing is a non-boolean.
+ */
+ resolve_status = BRW_NIR_NON_BOOLEAN;
+ } else {
+ /* At this point one of them is a true boolean and one is a
+ * boolean that needs a resolve. We could either resolve the
+ * unresolved source or we could resolve here. If we resolve
+ * the unresolved source then we get two resolves for the price
+ * of one. Just set this one to BOOLEAN_NO_RESOLVE and we'll
+ * let the code below force a resolve on the unresolved source.
+ */
+ resolve_status = BRW_NIR_BOOLEAN_NO_RESOLVE;
+ }
+ break;
+ }
+
+ default:
+ if (nir_alu_type_get_base_type(nir_op_infos[alu->op].output_type) == nir_type_bool) {
+ /* This instructions will turn into a CMP when we actually emit
+ * them 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);
+ } else {
+ resolve_status = BRW_NIR_NON_BOOLEAN;
+ }
+ }
+
+ /* If the destination is SSA, go ahead allow unresolved booleans.
+ * If the destination register doesn't have a well-defined parent_instr
+ * we need to resolve immediately.
+ */
+ if (!alu->dest.dest.is_ssa &&
+ resolve_status == BRW_NIR_BOOLEAN_UNRESOLVED) {
+ resolve_status = BRW_NIR_BOOLEAN_NEEDS_RESOLVE;
+ }
+
+ instr->pass_flags = (instr->pass_flags & ~BRW_NIR_BOOLEAN_MASK) |
+ resolve_status;
+
+ /* Finally, resolve sources if it's needed */
+ switch (resolve_status) {
+ case BRW_NIR_BOOLEAN_NEEDS_RESOLVE:
+ case BRW_NIR_BOOLEAN_UNRESOLVED:
+ /* This instruction is either unresolved or we're doing the
+ * resolve here; leave the sources alone.
+ */
+ break;
+
+ case BRW_NIR_BOOLEAN_NO_RESOLVE:
+ case BRW_NIR_NON_BOOLEAN:
+ nir_foreach_src(instr, src_mark_needs_resolve, NULL);
+ break;
+
+ default:
+ unreachable("Invalid boolean flag");
+ }
+
+ break;
+ }
+
+ case nir_instr_type_load_const: {
+ nir_load_const_instr *load = nir_instr_as_load_const(instr);
+
+ /* For load_const instructions, it's a boolean exactly when it holds
+ * one of the values NIR_TRUE or NIR_FALSE.
+ *
+ * Since load_const instructions don't have any sources, we don't
+ * have to worry about resolving them.
+ */
+ instr->pass_flags &= ~BRW_NIR_BOOLEAN_MASK;
+ if (load->value.u32[0] == NIR_TRUE || load->value.u32[0] == NIR_FALSE) {
+ instr->pass_flags |= BRW_NIR_BOOLEAN_NO_RESOLVE;
+ } else {
+ instr->pass_flags |= BRW_NIR_NON_BOOLEAN;
+ }
+ continue;
+ }
+
+ default:
+ /* Everything else is an unknown non-boolean value and needs to
+ * have all sources resolved.
+ */
+ instr->pass_flags = (instr->pass_flags & ~BRW_NIR_BOOLEAN_MASK) |
+ BRW_NIR_NON_BOOLEAN;
+ nir_foreach_src(instr, src_mark_needs_resolve, NULL);
+ continue;
+ }
+ }
+
+ nir_if *following_if = nir_block_get_following_if(block);
+ if (following_if)
+ src_mark_needs_resolve(&following_if->condition, NULL);
+
+ return true;
+}
+
+static void
+analyze_boolean_resolves_impl(nir_function_impl *impl)
+{
+ nir_foreach_block(block, impl) {
+ analyze_boolean_resolves_block(block);
+ }
+}
+
+void
+brw_nir_analyze_boolean_resolves(nir_shader *shader)
+{
+ nir_foreach_function(function, shader) {
+ if (function->impl)
+ analyze_boolean_resolves_impl(function->impl);
+ }
+}