Cycles: Move QBVH near/far offset calculation to an utility function

Just preparing for new optimization to be used in all traversal implementation.

Should be no measurable difference.

2 files changed, 39 insertions, 56 deletions

diff --git a/intern/cycles/kernel/bvh/qbvh_nodes.h b/intern/cycles/kernel/bvh/qbvh_nodes.h
index 2ee2a393e80..6d22f0b0d6a 100644
--- a/intern/cycles/kernel/bvh/qbvh_nodes.h
+++ b/intern/cycles/kernel/bvh/qbvh_nodes.h
@@ -21,6 +21,36 @@ struct QBVHStackItem {
 	float dist;
 };
 
+ccl_device_inline void qbvh_near_far_idx_calc(const float3& idir,
+                                              int *ccl_restrict near_x,
+                                              int *ccl_restrict near_y,
+                                              int *ccl_restrict near_z,
+                                              int *ccl_restrict far_x,
+                                              int *ccl_restrict far_y,
+                                              int *ccl_restrict far_z)
+
+{
+#ifdef __KERNEL_SSE__
+	*near_x = 0; *far_x = 1;
+	*near_y = 2; *far_y = 3;
+	*near_z = 4; *far_z = 5;
+
+	const size_t mask = movemask(ssef(idir.m128));
+
+	const int mask_x = mask & 1;
+	const int mask_y = (mask & 2) >> 1;
+	const int mask_z = (mask & 4) >> 2;
+
+	*near_x += mask_x; *far_x -= mask_x;
+	*near_y += mask_y; *far_y -= mask_y;
+	*near_z += mask_z; *far_z -= mask_z;
+#else
+	if(idir.x >= 0.0f) { *near_x = 0; *far_x = 1; } else { *near_x = 1; *far_x = 0; }
+	if(idir.y >= 0.0f) { *near_y = 2; *far_y = 3; } else { *near_y = 3; *far_y = 2; }
+	if(idir.z >= 0.0f) { *near_z = 4; *far_z = 5; } else { *near_z = 5; *far_z = 4; }
+#endif
+}
+
 /* TOOD(sergey): Investigate if using intrinsics helps for both
  * stack item swap and float comparison.
  */
diff --git a/intern/cycles/kernel/bvh/qbvh_traversal.h b/intern/cycles/kernel/bvh/qbvh_traversal.h
index b9da539306b..f2d8e558dcc 100644
--- a/intern/cycles/kernel/bvh/qbvh_traversal.h
+++ b/intern/cycles/kernel/bvh/qbvh_traversal.h
@@ -100,27 +100,11 @@ ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
 #endif
 
 	/* Offsets to select the side that becomes the lower or upper bound. */
-#ifdef __KERNEL_SSE__
-	int near_x = 0, near_y = 2, near_z = 4;
-	int far_x = 1, far_y = 3, far_z = 5;
-
-	const size_t mask = movemask(ssef(idir.m128));
-
-	const int mask_x = mask & 1;
-	const int mask_y = (mask & 2) >> 1;
-	const int mask_z = (mask & 4) >> 2;
-
-	near_x += mask_x; far_x -= mask_x;
-	near_y += mask_y; far_y -= mask_y;
-	near_z += mask_z; far_z -= mask_z;
-#else
 	int near_x, near_y, near_z;
 	int far_x, far_y, far_z;
-
-	if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
-	if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
-	if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
-#endif
+	qbvh_near_far_idx_calc(idir,
+	                       &near_x, &near_y, &near_z,
+	                       &far_x, &far_y, &far_z);
 
 	IsectPrecalc isect_precalc;
 	triangle_intersect_precalc(dir, &isect_precalc);
@@ -442,24 +426,9 @@ ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
 					qbvh_instance_push(kg, object, ray, &P, &dir, &idir, &isect->t, &node_dist);
 #  endif
 
-#ifdef __KERNEL_SSE__
-					near_x = 0; near_y = 2; near_z = 4;
-					far_x = 1; far_y = 3; far_z = 5;
-
-					const size_t mask = movemask(ssef(idir.m128));
-
-					const int mask_x = mask & 1;
-					const int mask_y = (mask & 2) >> 1;
-					const int mask_z = (mask & 4) >> 2;
-
-					near_x += mask_x; far_x -= mask_x;
-					near_y += mask_y; far_y -= mask_y;
-					near_z += mask_z; far_z -= mask_z;
-#else
-					if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
-					if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
-					if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
-#endif
+					qbvh_near_far_idx_calc(idir,
+					                       &near_x, &near_y, &near_z,
+					                       &far_x, &far_y, &far_z);
 					tfar = ssef(isect->t);
 #  if BVH_FEATURE(BVH_HAIR)
 					dir4 = sse3f(ssef(dir.x), ssef(dir.y), ssef(dir.z));
@@ -499,25 +468,9 @@ ccl_device bool BVH_FUNCTION_FULL_NAME(QBVH)(KernelGlobals *kg,
 			bvh_instance_pop(kg, object, ray, &P, &dir, &idir, &isect->t);
 #  endif
 
-#ifdef __KERNEL_SSE__
-			near_x = 0; near_y = 2; near_z = 4;
-			far_x = 1; far_y = 3; far_z = 5;
-
-			const size_t mask = movemask(ssef(idir.m128));
-
-			const int mask_x = mask & 1;
-			const int mask_y = (mask & 2) >> 1;
-			const int mask_z = (mask & 4) >> 2;
-
-			near_x += mask_x; far_x -= mask_x;
-			near_y += mask_y; far_y -= mask_y;
-			near_z += mask_z; far_z -= mask_z;
-#else
-			if(idir.x >= 0.0f) { near_x = 0; far_x = 1; } else { near_x = 1; far_x = 0; }
-			if(idir.y >= 0.0f) { near_y = 2; far_y = 3; } else { near_y = 3; far_y = 2; }
-			if(idir.z >= 0.0f) { near_z = 4; far_z = 5; } else { near_z = 5; far_z = 4; }
-#endif
-
+			qbvh_near_far_idx_calc(idir,
+			                       &near_x, &near_y, &near_z,
+			                       &far_x, &far_y, &far_z);
 			tfar = ssef(isect->t);
 #  if BVH_FEATURE(BVH_HAIR)
 			dir4 = sse3f(ssef(dir.x), ssef(dir.y), ssef(dir.z));