Fix T92363: OptiX fails with ambient occlusion node, after recent changes

This triggered a compiler bug where it does not handle the sub.s16 PTX
instruction. Instead refactor the code so we don't need to do uint16_t
subtraction at all.

Also update OptiX device to remove the AO pass direct callable.

Thanks Patrick Mours for figuring this out.

6 files changed, 8 insertions, 17 deletions

diff --git a/intern/cycles/device/optix/device_impl.cpp b/intern/cycles/device/optix/device_impl.cpp
index 89f4b696b4c..29e46be7745 100644
--- a/intern/cycles/device/optix/device_impl.cpp
+++ b/intern/cycles/device/optix/device_impl.cpp
@@ -377,9 +377,6 @@ bool OptiXDevice::load_kernels(const uint kernel_features)
     group_descs[PG_CALL_SVM_BEVEL].callables.moduleDC = optix_module;
     group_descs[PG_CALL_SVM_BEVEL].callables.entryFunctionNameDC =
         "__direct_callable__svm_node_bevel";
-    group_descs[PG_CALL_AO_PASS].kind = OPTIX_PROGRAM_GROUP_KIND_CALLABLES;
-    group_descs[PG_CALL_AO_PASS].callables.moduleDC = optix_module;
-    group_descs[PG_CALL_AO_PASS].callables.entryFunctionNameDC = "__direct_callable__ao_pass";
   }
 
   optix_assert(optixProgramGroupCreate(
diff --git a/intern/cycles/device/optix/device_impl.h b/intern/cycles/device/optix/device_impl.h
index 3695ac6afc2..b20d42f8c61 100644
--- a/intern/cycles/device/optix/device_impl.h
+++ b/intern/cycles/device/optix/device_impl.h
@@ -45,7 +45,6 @@ enum {
   PG_HITS_MOTION,
   PG_CALL_SVM_AO,
   PG_CALL_SVM_BEVEL,
-  PG_CALL_AO_PASS,
   NUM_PROGRAM_GROUPS
 };
 
diff --git a/intern/cycles/kernel/integrator/integrator_shade_shadow.h b/intern/cycles/kernel/integrator/integrator_shade_shadow.h
index 2d056a0b76f..a82254e1dea 100644
--- a/intern/cycles/kernel/integrator/integrator_shade_shadow.h
+++ b/intern/cycles/kernel/integrator/integrator_shade_shadow.h
@@ -136,6 +136,7 @@ ccl_device_inline bool integrate_transparent_shadow(KernelGlobals kg,
 
       INTEGRATOR_STATE_WRITE(state, shadow_path, throughput) = throughput;
       INTEGRATOR_STATE_WRITE(state, shadow_path, transparent_bounce) += 1;
+      INTEGRATOR_STATE_WRITE(state, shadow_path, rng_offset) += PRNG_BOUNCE_NUM;
     }
 
     /* Note we do not need to check max_transparent_bounce here, the number
diff --git a/intern/cycles/kernel/integrator/integrator_shade_surface.h b/intern/cycles/kernel/integrator/integrator_shade_surface.h
index 2fb0dcc2097..3724b05c6b0 100644
--- a/intern/cycles/kernel/integrator/integrator_shade_surface.h
+++ b/intern/cycles/kernel/integrator/integrator_shade_surface.h
@@ -200,9 +200,8 @@ ccl_device_forceinline void integrate_surface_direct_light(KernelGlobals kg,
 
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, render_pixel_index) = INTEGRATOR_STATE(
       state, path, render_pixel_index);
-  INTEGRATOR_STATE_WRITE(
-      shadow_state, shadow_path, rng_offset) = INTEGRATOR_STATE(state, path, rng_offset) -
-                                               PRNG_BOUNCE_NUM * transparent_bounce;
+  INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_offset) = INTEGRATOR_STATE(
+      state, path, rng_offset);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_hash) = INTEGRATOR_STATE(
       state, path, rng_hash);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, sample) = INTEGRATOR_STATE(
@@ -370,9 +369,8 @@ ccl_device_forceinline void integrate_surface_ao_pass(
 
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, render_pixel_index) = INTEGRATOR_STATE(
       state, path, render_pixel_index);
-  INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_offset) =
-      INTEGRATOR_STATE(state, path, rng_offset) -
-      PRNG_BOUNCE_NUM * INTEGRATOR_STATE(state, path, transparent_bounce);
+  INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_offset) = INTEGRATOR_STATE(
+      state, path, rng_offset);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_hash) = INTEGRATOR_STATE(
       state, path, rng_hash);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, sample) = INTEGRATOR_STATE(
diff --git a/intern/cycles/kernel/integrator/integrator_shade_volume.h b/intern/cycles/kernel/integrator/integrator_shade_volume.h
index 1dd701237a8..d0aabb550c0 100644
--- a/intern/cycles/kernel/integrator/integrator_shade_volume.h
+++ b/intern/cycles/kernel/integrator/integrator_shade_volume.h
@@ -799,9 +799,8 @@ ccl_device_forceinline void integrate_volume_direct_light(
 
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, render_pixel_index) = INTEGRATOR_STATE(
       state, path, render_pixel_index);
-  INTEGRATOR_STATE_WRITE(
-      shadow_state, shadow_path, rng_offset) = INTEGRATOR_STATE(state, path, rng_offset) -
-                                               PRNG_BOUNCE_NUM * transparent_bounce;
+  INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_offset) = INTEGRATOR_STATE(
+      state, path, rng_offset);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, rng_hash) = INTEGRATOR_STATE(
       state, path, rng_hash);
   INTEGRATOR_STATE_WRITE(shadow_state, shadow_path, sample) = INTEGRATOR_STATE(
diff --git a/intern/cycles/kernel/kernel_path_state.h b/intern/cycles/kernel/kernel_path_state.h
index 428eb3498f7..a0584f0b219 100644
--- a/intern/cycles/kernel/kernel_path_state.h
+++ b/intern/cycles/kernel/kernel_path_state.h
@@ -299,11 +299,8 @@ ccl_device_inline void path_state_rng_load(ConstIntegratorState state,
 ccl_device_inline void shadow_path_state_rng_load(ConstIntegratorShadowState state,
                                                   ccl_private RNGState *rng_state)
 {
-  const uint shadow_bounces = INTEGRATOR_STATE(state, shadow_path, transparent_bounce);
-
   rng_state->rng_hash = INTEGRATOR_STATE(state, shadow_path, rng_hash);
-  rng_state->rng_offset = INTEGRATOR_STATE(state, shadow_path, rng_offset) +
-                          PRNG_BOUNCE_NUM * shadow_bounces;
+  rng_state->rng_offset = INTEGRATOR_STATE(state, shadow_path, rng_offset);
   rng_state->sample = INTEGRATOR_STATE(state, shadow_path, sample);
 }