Cycles: OpenCL kernel split

This commit contains all the work related on the AMD megakernel split work
which was mainly done by Varun Sundar, George Kyriazis and Lenny Wang, plus
some help from Sergey Sharybin, Martijn Berger, Thomas Dinges and likely
someone else which we're forgetting to mention.

Currently only AMD cards are enabled for the new split kernel, but it is
possible to force split opencl kernel to be used by setting the following
environment variable: CYCLES_OPENCL_SPLIT_KERNEL_TEST=1.

Not all the features are supported yet, and that being said no motion blur,
camera blur, SSS and volumetrics for now. Also transparent shadows are
disabled on AMD device because of some compiler bug.

This kernel is also only implements regular path tracing and supporting
branched one will take a bit. Branched path tracing is exposed to the
interface still, which is a bit misleading and will be hidden there soon.

More feature will be enabled once they're ported to the split kernel and
tested.

Neither regular CPU nor CUDA has any difference, they're generating the
same exact code, which means no regressions/improvements there.

Based on the research paper:

  https://research.nvidia.com/sites/default/files/publications/laine2013hpg_paper.pdf

Here's the documentation:

  https://docs.google.com/document/d/1LuXW-CV-sVJkQaEGZlMJ86jZ8FmoPfecaMdR-oiWbUY/edit

Design discussion of the patch:

  https://developer.blender.org/T44197

Differential Revision: https://developer.blender.org/D1200

1 files changed, 21 insertions, 21 deletions

diff --git a/intern/cycles/kernel/geom/geom_triangle.h b/intern/cycles/kernel/geom/geom_triangle.h
index dd3928682e3..995dfac5b09 100644
--- a/intern/cycles/kernel/geom/geom_triangle.h
+++ b/intern/cycles/kernel/geom/geom_triangle.h
@@ -27,14 +27,14 @@ CCL_NAMESPACE_BEGIN
 ccl_device_inline float3 triangle_normal(KernelGlobals *kg, ShaderData *sd)
 {
 	/* load triangle vertices */
-	float4 tri_vindex = kernel_tex_fetch(__tri_vindex, sd->prim);
+	float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
 
 	float3 v0 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.x)));
 	float3 v1 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.y)));
 	float3 v2 = float4_to_float3(kernel_tex_fetch(__tri_verts, __float_as_int(tri_vindex.z)));
 	
 	/* return normal */
-	if(sd->flag & SD_NEGATIVE_SCALE_APPLIED)
+	if(ccl_fetch(sd, flag) & SD_NEGATIVE_SCALE_APPLIED)
 		return normalize(cross(v2 - v0, v1 - v0));
 	else
 		return normalize(cross(v1 - v0, v2 - v0));
@@ -94,7 +94,7 @@ ccl_device_inline float3 triangle_smooth_normal(KernelGlobals *kg, int prim, flo
 
 /* Ray differentials on triangle */
 
-ccl_device_inline void triangle_dPdudv(KernelGlobals *kg, int prim, float3 *dPdu, float3 *dPdv)
+ccl_device_inline void triangle_dPdudv(KernelGlobals *kg, int prim, ccl_addr_space float3 *dPdu, ccl_addr_space float3 *dPdv)
 {
 	/* fetch triangle vertex coordinates */
 	float4 tri_vindex = kernel_tex_fetch(__tri_vindex, prim);
@@ -116,34 +116,34 @@ ccl_device float triangle_attribute_float(KernelGlobals *kg, const ShaderData *s
 		if(dx) *dx = 0.0f;
 		if(dy) *dy = 0.0f;
 
-		return kernel_tex_fetch(__attributes_float, offset + sd->prim);
+		return kernel_tex_fetch(__attributes_float, offset + ccl_fetch(sd, prim));
 	}
 	else if(elem == ATTR_ELEMENT_VERTEX || elem == ATTR_ELEMENT_VERTEX_MOTION) {
-		float4 tri_vindex = kernel_tex_fetch(__tri_vindex, sd->prim);
+		float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
 
 		float f0 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.x));
 		float f1 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.y));
 		float f2 = kernel_tex_fetch(__attributes_float, offset + __float_as_int(tri_vindex.z));
 
 #ifdef __RAY_DIFFERENTIALS__
-		if(dx) *dx = sd->du.dx*f0 + sd->dv.dx*f1 - (sd->du.dx + sd->dv.dx)*f2;
-		if(dy) *dy = sd->du.dy*f0 + sd->dv.dy*f1 - (sd->du.dy + sd->dv.dy)*f2;
+		if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
+		if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
 #endif
 
-		return sd->u*f0 + sd->v*f1 + (1.0f - sd->u - sd->v)*f2;
+		return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
 	}
 	else if(elem == ATTR_ELEMENT_CORNER) {
-		int tri = offset + sd->prim*3;
+		int tri = offset + ccl_fetch(sd, prim)*3;
 		float f0 = kernel_tex_fetch(__attributes_float, tri + 0);
 		float f1 = kernel_tex_fetch(__attributes_float, tri + 1);
 		float f2 = kernel_tex_fetch(__attributes_float, tri + 2);
 
 #ifdef __RAY_DIFFERENTIALS__
-		if(dx) *dx = sd->du.dx*f0 + sd->dv.dx*f1 - (sd->du.dx + sd->dv.dx)*f2;
-		if(dy) *dy = sd->du.dy*f0 + sd->dv.dy*f1 - (sd->du.dy + sd->dv.dy)*f2;
+		if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
+		if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
 #endif
 
-		return sd->u*f0 + sd->v*f1 + (1.0f - sd->u - sd->v)*f2;
+		return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
 	}
 	else {
 		if(dx) *dx = 0.0f;
@@ -159,24 +159,24 @@ ccl_device float3 triangle_attribute_float3(KernelGlobals *kg, const ShaderData
 		if(dx) *dx = make_float3(0.0f, 0.0f, 0.0f);
 		if(dy) *dy = make_float3(0.0f, 0.0f, 0.0f);
 
-		return float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + sd->prim));
+		return float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + ccl_fetch(sd, prim)));
 	}
 	else if(elem == ATTR_ELEMENT_VERTEX || elem == ATTR_ELEMENT_VERTEX_MOTION) {
-		float4 tri_vindex = kernel_tex_fetch(__tri_vindex, sd->prim);
+		float4 tri_vindex = kernel_tex_fetch(__tri_vindex, ccl_fetch(sd, prim));
 
 		float3 f0 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.x)));
 		float3 f1 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.y)));
 		float3 f2 = float4_to_float3(kernel_tex_fetch(__attributes_float3, offset + __float_as_int(tri_vindex.z)));
 
 #ifdef __RAY_DIFFERENTIALS__
-		if(dx) *dx = sd->du.dx*f0 + sd->dv.dx*f1 - (sd->du.dx + sd->dv.dx)*f2;
-		if(dy) *dy = sd->du.dy*f0 + sd->dv.dy*f1 - (sd->du.dy + sd->dv.dy)*f2;
+		if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
+		if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
 #endif
 
-		return sd->u*f0 + sd->v*f1 + (1.0f - sd->u - sd->v)*f2;
+		return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
 	}
 	else if(elem == ATTR_ELEMENT_CORNER || elem == ATTR_ELEMENT_CORNER_BYTE) {
-		int tri = offset + sd->prim*3;
+		int tri = offset + ccl_fetch(sd, prim)*3;
 		float3 f0, f1, f2;
 
 		if(elem == ATTR_ELEMENT_CORNER) {
@@ -191,11 +191,11 @@ ccl_device float3 triangle_attribute_float3(KernelGlobals *kg, const ShaderData
 		}
 
 #ifdef __RAY_DIFFERENTIALS__
-		if(dx) *dx = sd->du.dx*f0 + sd->dv.dx*f1 - (sd->du.dx + sd->dv.dx)*f2;
-		if(dy) *dy = sd->du.dy*f0 + sd->dv.dy*f1 - (sd->du.dy + sd->dv.dy)*f2;
+		if(dx) *dx = ccl_fetch(sd, du).dx*f0 + ccl_fetch(sd, dv).dx*f1 - (ccl_fetch(sd, du).dx + ccl_fetch(sd, dv).dx)*f2;
+		if(dy) *dy = ccl_fetch(sd, du).dy*f0 + ccl_fetch(sd, dv).dy*f1 - (ccl_fetch(sd, du).dy + ccl_fetch(sd, dv).dy)*f2;
 #endif
 
-		return sd->u*f0 + sd->v*f1 + (1.0f - sd->u - sd->v)*f2;
+		return ccl_fetch(sd, u)*f0 + ccl_fetch(sd, v)*f1 + (1.0f - ccl_fetch(sd, u) - ccl_fetch(sd, v))*f2;
 	}
 	else {
 		if(dx) *dx = make_float3(0.0f, 0.0f, 0.0f);