compiler: Bring over glsl compiler from alchemist-10.2.6+steamos-LunarG-1.1
diff --git a/icd/intel/compiler/shader/threadpool.c b/icd/intel/compiler/shader/threadpool.c
new file mode 100644
index 0000000..d6ed8c1
--- /dev/null
+++ b/icd/intel/compiler/shader/threadpool.c
@@ -0,0 +1,548 @@
+/*
+ * Mesa 3-D graphics library
+ *
+ * Copyright (C) 2014  LunarG, Inc.   All Rights Reserved.
+ *
+ * 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 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 <stdio.h>
+#include <stdbool.h>
+#include "c11/threads.h"
+#include "main/compiler.h"
+#include "main/simple_list.h"
+#include "threadpool.h"
+
+enum _mesa_threadpool_control {
+   MESA_THREADPOOL_NORMAL,    /* threads wait when there is no task */
+   MESA_THREADPOOL_QUIT,      /* threads quit when there is no task */
+   MESA_THREADPOOL_QUIT_NOW   /* threads quit as soon as possible */
+};
+
+enum _mesa_threadpool_task_state {
+   MESA_THREADPOOL_TASK_PENDING,    /* task is on the pending list */
+   MESA_THREADPOOL_TASK_ACTIVE,     /* task is being worked on */
+   MESA_THREADPOOL_TASK_COMPLETED,  /* task has been completed */
+   MESA_THREADPOOL_TASK_CANCELLED   /* task is cancelled */
+};
+
+struct _mesa_threadpool_task {
+   /* these are protected by the pool's mutex */
+   struct simple_node link; /* must be the first */
+   enum _mesa_threadpool_task_state state;
+   cnd_t completed;
+
+   void (*func)(void *);
+   void *data;
+};
+
+struct _mesa_threadpool {
+   mtx_t mutex;
+   int refcnt;
+   bool shutdown;
+
+   enum _mesa_threadpool_control thread_control;
+   thrd_t *threads;
+   int num_threads, max_threads;
+   int idle_threads; /* number of threads that are idle */
+   cnd_t thread_wakeup;
+   cnd_t thread_joined;
+
+   struct simple_node pending_tasks;
+   int num_pending_tasks;
+   int num_tasks;
+};
+
+static struct _mesa_threadpool_task *
+task_create(void)
+{
+   struct _mesa_threadpool_task *task;
+
+   task = malloc(sizeof(*task));
+   if (!task)
+      return NULL;
+
+   if (cnd_init(&task->completed)) {
+      free(task);
+      return NULL;
+   }
+
+   task->state = MESA_THREADPOOL_TASK_PENDING;
+
+   return task;
+}
+
+static void
+task_destroy(struct _mesa_threadpool_task *task)
+{
+   cnd_destroy(&task->completed);
+   free(task);
+}
+
+static void
+pool_exec_task(struct _mesa_threadpool *pool,
+               struct _mesa_threadpool_task *task)
+{
+   assert(task->state == MESA_THREADPOOL_TASK_PENDING);
+
+   remove_from_list(&task->link);
+   pool->num_pending_tasks--;
+
+   task->state = MESA_THREADPOOL_TASK_ACTIVE;
+
+   /* do the work! */
+   mtx_unlock(&pool->mutex);
+   task->func(task->data);
+   mtx_lock(&pool->mutex);
+
+   task->state = MESA_THREADPOOL_TASK_COMPLETED;
+}
+
+static int
+_mesa_threadpool_worker(void *arg)
+{
+   struct _mesa_threadpool *pool = (struct _mesa_threadpool *) arg;
+
+   mtx_lock(&pool->mutex);
+
+   while (true) {
+      struct _mesa_threadpool_task *task;
+
+      /* wait until there are tasks */
+      while (is_empty_list(&pool->pending_tasks) &&
+             pool->thread_control == MESA_THREADPOOL_NORMAL) {
+         pool->idle_threads++;
+         cnd_wait(&pool->thread_wakeup, &pool->mutex);
+         pool->idle_threads--;
+      }
+
+      if (pool->thread_control != MESA_THREADPOOL_NORMAL) {
+         if (pool->thread_control == MESA_THREADPOOL_QUIT_NOW ||
+             is_empty_list(&pool->pending_tasks))
+            break;
+      }
+
+      assert(!is_empty_list(&pool->pending_tasks));
+      task = (struct _mesa_threadpool_task *)
+         first_elem(&pool->pending_tasks);
+
+      pool_exec_task(pool, task);
+      cnd_signal(&task->completed);
+   }
+
+   mtx_unlock(&pool->mutex);
+
+   return 0;
+}
+
+/**
+ * Queue a new task.
+ */
+struct _mesa_threadpool_task *
+_mesa_threadpool_queue_task(struct _mesa_threadpool *pool,
+                            void (*func)(void *), void *data)
+{
+   struct _mesa_threadpool_task *task;
+
+   task = task_create();
+   if (!task)
+      return NULL;
+
+   task->func = func;
+   task->data = data;
+
+   mtx_lock(&pool->mutex);
+
+   if (unlikely(pool->shutdown)) {
+      mtx_unlock(&pool->mutex);
+      free(task);
+      return NULL;
+   }
+
+   /* someone is joining with the threads */
+   while (unlikely(pool->thread_control != MESA_THREADPOOL_NORMAL))
+      cnd_wait(&pool->thread_joined, &pool->mutex);
+
+   /* spawn threads as needed */
+   if (pool->idle_threads <= pool->num_pending_tasks &&
+       pool->num_threads < pool->max_threads) {
+      int err;
+
+      err = thrd_create(&pool->threads[pool->num_threads],
+                        _mesa_threadpool_worker, (void *) pool);
+      if (!err)
+         pool->num_threads++;
+
+      if (!pool->num_threads) {
+         mtx_unlock(&pool->mutex);
+         task_destroy(task);
+         return NULL;
+      }
+   }
+
+   insert_at_tail(&pool->pending_tasks, &task->link);
+   pool->num_tasks++;
+   pool->num_pending_tasks++;
+   cnd_signal(&pool->thread_wakeup);
+
+   mtx_unlock(&pool->mutex);
+
+   return task;
+}
+
+/**
+ * Wait and destroy the tasks.
+ */
+static bool
+pool_wait_tasks(struct _mesa_threadpool *pool,
+                struct _mesa_threadpool_task **tasks,
+                int num_tasks)
+{
+   bool all_completed = true;
+   int i;
+
+   for (i = 0; i < num_tasks; i++) {
+      struct _mesa_threadpool_task *task = tasks[i];
+
+      while (task->state != MESA_THREADPOOL_TASK_COMPLETED &&
+             task->state != MESA_THREADPOOL_TASK_CANCELLED)
+         cnd_wait(&task->completed, &pool->mutex);
+
+      if (task->state != MESA_THREADPOOL_TASK_COMPLETED)
+         all_completed = false;
+
+      task_destroy(task);
+   }
+
+   pool->num_tasks -= num_tasks;
+
+   return all_completed;
+}
+
+/**
+ * Wait for \p tasks to complete, and destroy them.  If some of \p tasks
+ * cannot not be completed, return false.
+ *
+ * This function can be called from within the worker threads.
+ */
+bool
+_mesa_threadpool_complete_tasks(struct _mesa_threadpool *pool,
+                                struct _mesa_threadpool_task **tasks,
+                                int num_tasks)
+{
+   bool prioritized = false, completed;
+   int i;
+
+   mtx_lock(&pool->mutex);
+
+   /* we need to do something about tasks that are pending */
+   for (i = 0; i < num_tasks; i++) {
+      struct _mesa_threadpool_task *task = tasks[i];
+
+      if (task->state != MESA_THREADPOOL_TASK_PENDING)
+         continue;
+
+      /* move them to the head so that they are executed next */
+      if (!prioritized) {
+         int j;
+
+         for (j = i + 1; j < num_tasks; j++) {
+            if (task->state == MESA_THREADPOOL_TASK_PENDING)
+               move_to_head(&pool->pending_tasks, &task->link);
+         }
+         prioritized = true;
+      }
+
+      /*
+       * Execute right away for we would have to wait for the worker threads
+       * otherwise, which is no faster.  More importantly, when this is called
+       * from within worker threads, there may be no idle thread available to
+       * execute them.
+       */
+      pool_exec_task(pool, task);
+   }
+
+   completed = pool_wait_tasks(pool, tasks, num_tasks);
+
+   mtx_unlock(&pool->mutex);
+
+   return completed;
+}
+
+/**
+ * This is equivalent to calling \p _mesa_threadpool_complete_tasks with one
+ * task.
+ */
+bool
+_mesa_threadpool_complete_task(struct _mesa_threadpool *pool,
+                               struct _mesa_threadpool_task *task)
+{
+   bool completed;
+
+   mtx_lock(&pool->mutex);
+
+   if (task->state == MESA_THREADPOOL_TASK_PENDING)
+      pool_exec_task(pool, task);
+
+   completed = pool_wait_tasks(pool, &task, 1);
+
+   mtx_unlock(&pool->mutex);
+
+   return completed;
+}
+
+static void
+pool_cancel_pending_tasks(struct _mesa_threadpool *pool)
+{
+   struct simple_node *node, *temp;
+
+   if (is_empty_list(&pool->pending_tasks))
+      return;
+
+   foreach_s(node, temp, &pool->pending_tasks) {
+      struct _mesa_threadpool_task *task =
+         (struct _mesa_threadpool_task *) node;
+
+      remove_from_list(&task->link);
+      task->state = MESA_THREADPOOL_TASK_CANCELLED;
+
+      /* in case some thread is already waiting */
+      cnd_signal(&task->completed);
+   }
+
+   pool->num_pending_tasks = 0;
+}
+
+static void
+pool_join_threads(struct _mesa_threadpool *pool, bool graceful)
+{
+   int joined_threads = 0;
+
+   if (!pool->num_threads)
+      return;
+
+   pool->thread_control = (graceful) ?
+      MESA_THREADPOOL_QUIT : MESA_THREADPOOL_QUIT_NOW;
+
+   while (joined_threads < pool->num_threads) {
+      int i = joined_threads, num_threads = pool->num_threads;
+
+      cnd_broadcast(&pool->thread_wakeup);
+      mtx_unlock(&pool->mutex);
+      while (i < num_threads)
+         thrd_join(pool->threads[i++], NULL);
+      mtx_lock(&pool->mutex);
+
+      joined_threads = num_threads;
+   }
+
+   pool->thread_control = MESA_THREADPOOL_NORMAL;
+   pool->num_threads = 0;
+   assert(!pool->idle_threads);
+}
+
+/**
+ * Join with all pool threads.  When \p graceful is true, wait for the pending
+ * tasks to be completed.
+ */
+void
+_mesa_threadpool_join(struct _mesa_threadpool *pool, bool graceful)
+{
+   mtx_lock(&pool->mutex);
+
+   /* someone is already joining with the threads */
+   while (unlikely(pool->thread_control != MESA_THREADPOOL_NORMAL))
+      cnd_wait(&pool->thread_joined, &pool->mutex);
+
+   if (pool->num_threads) {
+      pool_join_threads(pool, graceful);
+      /* wake up whoever is waiting */
+      cnd_broadcast(&pool->thread_joined);
+   }
+
+   if (!graceful)
+      pool_cancel_pending_tasks(pool);
+
+   assert(pool->num_threads == 0);
+   assert(is_empty_list(&pool->pending_tasks) && !pool->num_pending_tasks);
+
+   mtx_unlock(&pool->mutex);
+}
+
+/**
+ * After this call, no task can be queued.
+ */
+static void
+_mesa_threadpool_set_shutdown(struct _mesa_threadpool *pool)
+{
+   mtx_lock(&pool->mutex);
+   pool->shutdown = true;
+   mtx_unlock(&pool->mutex);
+}
+
+/**
+ * Decrease the reference count.  Destroy \p pool when the reference count
+ * reaches zero.
+ */
+void
+_mesa_threadpool_unref(struct _mesa_threadpool *pool)
+{
+   bool destroy = false;
+
+   mtx_lock(&pool->mutex);
+   pool->refcnt--;
+   destroy = (pool->refcnt == 0);
+   mtx_unlock(&pool->mutex);
+
+   if (destroy) {
+      _mesa_threadpool_join(pool, false);
+
+      if (pool->num_tasks) {
+         fprintf(stderr, "thread pool destroyed with %d tasks\n",
+               pool->num_tasks);
+      }
+
+      free(pool->threads);
+      cnd_destroy(&pool->thread_joined);
+      cnd_destroy(&pool->thread_wakeup);
+      mtx_destroy(&pool->mutex);
+      free(pool);
+   }
+}
+
+/**
+ * Increase the reference count.
+ */
+struct _mesa_threadpool *
+_mesa_threadpool_ref(struct _mesa_threadpool *pool)
+{
+   mtx_lock(&pool->mutex);
+   pool->refcnt++;
+   mtx_unlock(&pool->mutex);
+
+   return pool;
+}
+
+/**
+ * Create a thread pool.  As threads are spawned as needed, this is
+ * inexpensive.
+ */
+struct _mesa_threadpool *
+_mesa_threadpool_create(int max_threads)
+{
+   struct _mesa_threadpool *pool;
+
+   if (max_threads < 1)
+      return NULL;
+
+   pool = calloc(1, sizeof(*pool));
+   if (!pool)
+      return NULL;
+
+   if (mtx_init(&pool->mutex, mtx_plain)) {
+      free(pool);
+      return NULL;
+   }
+
+   pool->refcnt = 1;
+
+   if (cnd_init(&pool->thread_wakeup)) {
+      mtx_destroy(&pool->mutex);
+      free(pool);
+      return NULL;
+   }
+
+   if (cnd_init(&pool->thread_joined)) {
+      cnd_destroy(&pool->thread_wakeup);
+      mtx_destroy(&pool->mutex);
+      free(pool);
+      return NULL;
+   }
+
+   pool->thread_control = MESA_THREADPOOL_NORMAL;
+
+   pool->threads = malloc(sizeof(pool->threads[0]) * max_threads);
+   if (!pool->threads) {
+      cnd_destroy(&pool->thread_joined);
+      cnd_destroy(&pool->thread_wakeup);
+      mtx_destroy(&pool->mutex);
+      free(pool);
+      return NULL;
+   }
+
+   pool->max_threads = max_threads;
+
+   make_empty_list(&pool->pending_tasks);
+
+   return pool;
+}
+
+static mtx_t threadpool_lock = _MTX_INITIALIZER_NP;
+static struct _mesa_threadpool *threadpool;
+
+/**
+ * Get the singleton GLSL thread pool.  \p max_threads is honored only by the
+ * first call to this function.
+ */
+struct _mesa_threadpool *
+_mesa_glsl_get_threadpool(int max_threads)
+{
+   mtx_lock(&threadpool_lock);
+   if (!threadpool)
+      threadpool = _mesa_threadpool_create(max_threads);
+   if (threadpool)
+      _mesa_threadpool_ref(threadpool);
+   mtx_unlock(&threadpool_lock);
+
+   return threadpool;
+}
+
+/**
+ * Wait until all tasks are completed and threads are joined.
+ */
+void
+_mesa_glsl_wait_threadpool(void)
+{
+   mtx_lock(&threadpool_lock);
+   if (threadpool)
+      _mesa_threadpool_join(threadpool, true);
+   mtx_unlock(&threadpool_lock);
+}
+
+/**
+ * Destroy the GLSL thread pool.
+ */
+void
+_mesa_glsl_destroy_threadpool(void)
+{
+   mtx_lock(&threadpool_lock);
+   if (threadpool) {
+      /*
+       * This is called from _mesa_destroy_shader_compiler().  No new task is
+       * allowed since this point.  But contexts, who also own references to
+       * the pool, can still complete tasks that have been queued.
+       */
+      _mesa_threadpool_set_shutdown(threadpool);
+
+      _mesa_threadpool_join(threadpool, false);
+      _mesa_threadpool_unref(threadpool);
+      threadpool = NULL;
+   }
+   mtx_unlock(&threadpool_lock);
+}