--- /dev/null
+/*
+ * Copyright © 2013 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.
+ */
+
+#include "ir.h"
+#include "ir_uniform.h"
+#include "linker.h"
+#include "program/hash_table.h"
+#include "main/macros.h"
+
+namespace {
+ /*
+ * Atomic counter as seen by the program.
+ */
+ struct active_atomic_counter {
+ unsigned id;
+ ir_variable *var;
+ };
+
+ /*
+ * Atomic counter buffer referenced by the program. There is a one
+ * to one correspondence between these and the objects that can be
+ * queried using glGetActiveAtomicCounterBufferiv().
+ */
+ struct active_atomic_buffer {
+ active_atomic_buffer()
+ : counters(0), num_counters(0), stage_references(), size(0)
+ {}
+
+ ~active_atomic_buffer()
+ {
+ free(counters);
+ }
+
+ void push_back(unsigned id, ir_variable *var)
+ {
+ counters = (active_atomic_counter *)
+ realloc(counters, sizeof(active_atomic_counter) * (num_counters + 1));
+
+ counters[num_counters].id = id;
+ counters[num_counters].var = var;
+ num_counters++;
+ }
+
+ active_atomic_counter *counters;
+ unsigned num_counters;
+ unsigned stage_references[MESA_SHADER_TYPES];
+ unsigned size;
+ };
+
+ int
+ cmp_actives(const void *a, const void *b)
+ {
+ const active_atomic_counter *const first = (active_atomic_counter *) a;
+ const active_atomic_counter *const second = (active_atomic_counter *) b;
+
+ return int(first->var->atomic.offset) - int(second->var->atomic.offset);
+ }
+
+ bool
+ check_atomic_counters_overlap(const ir_variable *x, const ir_variable *y)
+ {
+ return ((x->atomic.offset >= y->atomic.offset &&
+ x->atomic.offset < y->atomic.offset + y->type->atomic_size()) ||
+ (y->atomic.offset >= x->atomic.offset &&
+ y->atomic.offset < x->atomic.offset + x->type->atomic_size()));
+ }
+
+ active_atomic_buffer *
+ find_active_atomic_counters(struct gl_context *ctx,
+ struct gl_shader_program *prog,
+ unsigned *num_buffers)
+ {
+ active_atomic_buffer *const buffers =
+ new active_atomic_buffer[ctx->Const.MaxAtomicBufferBindings];
+
+ *num_buffers = 0;
+
+ for (unsigned i = 0; i < MESA_SHADER_TYPES; ++i) {
+ struct gl_shader *sh = prog->_LinkedShaders[i];
+ if (sh == NULL)
+ continue;
+
+ foreach_list(node, sh->ir) {
+ ir_variable *var = ((ir_instruction *)node)->as_variable();
+
+ if (var && var->type->contains_atomic()) {
+ unsigned id;
+ bool found = prog->UniformHash->get(id, var->name);
+ assert(found);
+ active_atomic_buffer *buf = &buffers[var->binding];
+
+ /* If this is the first time the buffer is used, increment
+ * the counter of buffers used.
+ */
+ if (buf->size == 0)
+ (*num_buffers)++;
+
+ buf->push_back(id, var);
+
+ buf->stage_references[i]++;
+ buf->size = MAX2(buf->size, var->atomic.offset +
+ var->type->atomic_size());
+ }
+ }
+ }
+
+ for (unsigned i = 0; i < ctx->Const.MaxAtomicBufferBindings; i++) {
+ if (buffers[i].size == 0)
+ continue;
+
+ qsort(buffers[i].counters, buffers[i].num_counters,
+ sizeof(active_atomic_counter),
+ cmp_actives);
+
+ for (unsigned j = 1; j < buffers[i].num_counters; j++) {
+ /* If an overlapping counter found, it must be a reference to the
+ * same counter from a different shader stage.
+ */
+ if (check_atomic_counters_overlap(buffers[i].counters[j-1].var,
+ buffers[i].counters[j].var)
+ && strcmp(buffers[i].counters[j-1].var->name,
+ buffers[i].counters[j].var->name) != 0) {
+ linker_error(prog, "Atomic counter %s declared at offset %d "
+ "which is already in use.",
+ buffers[i].counters[j].var->name,
+ buffers[i].counters[j].var->atomic.offset);
+ }
+ }
+ }
+ return buffers;
+ }
+}
+
+void
+link_assign_atomic_counter_resources(struct gl_context *ctx,
+ struct gl_shader_program *prog)
+{
+ unsigned num_buffers;
+ active_atomic_buffer *abs =
+ find_active_atomic_counters(ctx, prog, &num_buffers);
+
+ prog->AtomicBuffers = rzalloc_array(prog, gl_active_atomic_buffer,
+ num_buffers);
+ prog->NumAtomicBuffers = num_buffers;
+
+ unsigned i = 0;
+ for (unsigned binding = 0;
+ binding < ctx->Const.MaxAtomicBufferBindings;
+ binding++) {
+
+ /* If the binding was not used, skip.
+ */
+ if (abs[binding].size == 0)
+ continue;
+
+ active_atomic_buffer &ab = abs[binding];
+ gl_active_atomic_buffer &mab = prog->AtomicBuffers[i];
+
+ /* Assign buffer-specific fields. */
+ mab.Binding = binding;
+ mab.MinimumSize = ab.size;
+ mab.Uniforms = rzalloc_array(prog->AtomicBuffers, GLuint,
+ ab.num_counters);
+ mab.NumUniforms = ab.num_counters;
+
+ /* Assign counter-specific fields. */
+ for (unsigned j = 0; j < ab.num_counters; j++) {
+ ir_variable *const var = ab.counters[j].var;
+ const unsigned id = ab.counters[j].id;
+ gl_uniform_storage *const storage = &prog->UniformStorage[id];
+
+ mab.Uniforms[j] = id;
+ var->atomic.buffer_index = i;
+ storage->atomic_buffer_index = i;
+ storage->offset = var->atomic.offset;
+ storage->array_stride = (var->type->is_array() ?
+ var->type->element_type()->atomic_size() : 0);
+ }
+
+ /* Assign stage-specific fields. */
+ for (unsigned j = 0; j < MESA_SHADER_TYPES; ++j)
+ mab.StageReferences[j] =
+ (ab.stage_references[j] ? GL_TRUE : GL_FALSE);
+
+ i++;
+ }
+
+ delete [] abs;
+ assert(i == num_buffers);
+}
+
+void
+link_check_atomic_counter_resources(struct gl_context *ctx,
+ struct gl_shader_program *prog)
+{
+ STATIC_ASSERT(MESA_SHADER_TYPES == 3);
+ static const char *shader_names[MESA_SHADER_TYPES] = {
+ "vertex", "geometry", "fragment"
+ };
+ const unsigned max_atomic_counters[MESA_SHADER_TYPES] = {
+ ctx->Const.VertexProgram.MaxAtomicCounters,
+ ctx->Const.GeometryProgram.MaxAtomicCounters,
+ ctx->Const.FragmentProgram.MaxAtomicCounters
+ };
+ const unsigned max_atomic_buffers[MESA_SHADER_TYPES] = {
+ ctx->Const.VertexProgram.MaxAtomicBuffers,
+ ctx->Const.GeometryProgram.MaxAtomicBuffers,
+ ctx->Const.FragmentProgram.MaxAtomicBuffers
+ };
+ unsigned num_buffers;
+ active_atomic_buffer *const abs =
+ find_active_atomic_counters(ctx, prog, &num_buffers);
+ unsigned atomic_counters[MESA_SHADER_TYPES] = {};
+ unsigned atomic_buffers[MESA_SHADER_TYPES] = {};
+ unsigned total_atomic_counters = 0;
+ unsigned total_atomic_buffers = 0;
+
+ /* Sum the required resources. Note that this counts buffers and
+ * counters referenced by several shader stages multiple times
+ * against the combined limit -- That's the behavior the spec
+ * requires.
+ */
+ for (unsigned i = 0; i < ctx->Const.MaxAtomicBufferBindings; i++) {
+ if (abs[i].size == 0)
+ continue;
+
+ for (unsigned j = 0; j < MESA_SHADER_TYPES; ++j) {
+ const unsigned n = abs[i].stage_references[j];
+
+ if (n) {
+ atomic_counters[j] += n;
+ total_atomic_counters += n;
+ atomic_buffers[j]++;
+ total_atomic_buffers++;
+ }
+ }
+ }
+
+ /* Check that they are within the supported limits. */
+ for (unsigned i = 0; i < MESA_SHADER_TYPES; i++) {
+ if (atomic_counters[i] > max_atomic_counters[i])
+ linker_error(prog, "Too many %s shader atomic counters",
+ shader_names[i]);
+
+ if (atomic_buffers[i] > max_atomic_buffers[i])
+ linker_error(prog, "Too many %s shader atomic counter buffers",
+ shader_names[i]);
+ }
+
+ if (total_atomic_counters > ctx->Const.MaxCombinedAtomicCounters)
+ linker_error(prog, "Too many combined atomic counters");
+
+ if (total_atomic_buffers > ctx->Const.MaxCombinedAtomicBuffers)
+ linker_error(prog, "Too many combined atomic buffers");
+
+ delete [] abs;
+}