Fix T44833: Can't use ccl_local space in non-kernel functions

This commit re-shuffles code in split kernel once again and makes it so common
parts which is in the headers is only responsible to making all the work needed
for specified ray index. Getting ray index, checking for it's validity and
enqueuing tasks are now happening in the device specified part of the kernel.

This actually makes sense because enqueuing is indeed device-specified and i.e.
with CUDA we'll want to enqueue kernels from kernel and avoid CPU roundtrip.

TODO:
- Kernel comments are still placed in the common header files, but since queue
  related stuff is not passed to those functions those comments might need to
  be split as well.

  Just currently read them considering that they're also covering the way how
  all devices are invoking the common code path.

- Arguments might need to be wrapped into KernelGlobals, so we don't ened to
  pass all them around as function arguments.

1 files changed, 17 insertions, 50 deletions

diff --git a/intern/cycles/kernel/split/kernel_lamp_emission.h b/intern/cycles/kernel/split/kernel_lamp_emission.h
index b804bfc8630..e5fdb637a50 100644
--- a/intern/cycles/kernel/split/kernel_lamp_emission.h
+++ b/intern/cycles/kernel/split/kernel_lamp_emission.h
@@ -16,8 +16,7 @@
 
 #include "kernel_split_common.h"
 
-/*
- * Note on kernel_lamp_emission
+/* Note on kernel_lamp_emission
  * This is the 3rd kernel in the ray-tracing logic. This is the second of the
  * path-iteration kernels. This kernel takes care of the indirect lamp emission logic.
  * This kernel operates on QUEUE_ACTIVE_AND_REGENERATED_RAYS. It processes rays of state RAY_ACTIVE
@@ -40,55 +39,23 @@
  *
  * note : shader_data is neither input nor output. Its just filled and consumed in the same, kernel_lamp_emission, kernel.
  */
-__kernel void kernel_lamp_emission(
-	ccl_global char *globals,
-	ccl_constant KernelData *data,
-	ccl_global char *shader_data,               /* Required for lamp emission */
-	ccl_global float3 *throughput_coop,         /* Required for lamp emission */
-	PathRadiance *PathRadiance_coop, /* Required for lamp emission */
-	ccl_global Ray *Ray_coop,                   /* Required for lamp emission */
-	ccl_global PathState *PathState_coop,       /* Required for lamp emission */
-	Intersection *Intersection_coop, /* Required for lamp emission */
-	ccl_global char *ray_state,                 /* Denotes the state of each ray */
-	int sw, int sh,
-	ccl_global int *Queue_data,                 /* Memory for queues */
-	ccl_global int *Queue_index,                /* Tracks the number of elements in queues */
-	int queuesize,                              /* Size (capacity) of queues */
-	ccl_global char *use_queues_flag,           /* used to decide if this kernel should use queues to fetch ray index */
-	int parallel_samples                        /* Number of samples to be processed in parallel */
-	)
+ccl_device void kernel_lamp_emission(
+        ccl_global char *globals,
+        ccl_constant KernelData *data,
+        ccl_global char *shader_data,          /* Required for lamp emission */
+        ccl_global float3 *throughput_coop,    /* Required for lamp emission */
+        PathRadiance *PathRadiance_coop,       /* Required for lamp emission */
+        ccl_global Ray *Ray_coop,              /* Required for lamp emission */
+        ccl_global PathState *PathState_coop,  /* Required for lamp emission */
+        Intersection *Intersection_coop,       /* Required for lamp emission */
+        ccl_global char *ray_state,            /* Denotes the state of each ray */
+        int sw, int sh,
+        ccl_global char *use_queues_flag,      /* Used to decide if this kernel should use
+                                                * queues to fetch ray index
+                                                */
+        int parallel_samples,                  /* Number of samples to be processed in parallel */
+        int ray_index)
 {
-	int x = get_global_id(0);
-	int y = get_global_id(1);
-
-	/* We will empty this queue in this kernel */
-	if(get_global_id(0) == 0 && get_global_id(1) == 0) {
-		Queue_index[QUEUE_ACTIVE_AND_REGENERATED_RAYS] = 0;
-	}
-
-	/* Fetch use_queues_flag */
-	ccl_local char local_use_queues_flag;
-	if(get_local_id(0) == 0 && get_local_id(1) == 0) {
-		local_use_queues_flag = use_queues_flag[0];
-	}
-	barrier(CLK_LOCAL_MEM_FENCE);
-
-	int ray_index;
-	if(local_use_queues_flag) {
-		int thread_index = get_global_id(1) * get_global_size(0) + get_global_id(0);
-		ray_index = get_ray_index(thread_index, QUEUE_ACTIVE_AND_REGENERATED_RAYS, Queue_data, queuesize, 1);
-
-		if(ray_index == QUEUE_EMPTY_SLOT) {
-			return;
-		}
-	} else {
-		if(x < (sw * parallel_samples) && y < sh){
-			ray_index = x + y * (sw * parallel_samples);
-		} else {
-			return;
-		}
-	}
-
 	if(IS_STATE(ray_state, ray_index, RAY_ACTIVE) || IS_STATE(ray_state, ray_index, RAY_HIT_BACKGROUND)) {
 		KernelGlobals *kg = (KernelGlobals *)globals;
 		ShaderData *sd = (ShaderData *)shader_data;