Fix T53270: crash with multiscatter GGX after recent refactoring.

In fact this was an existing issue when exceeding the number of available
closure, but it's more common now that we set the number to 0 for shadows
and emission

3 files changed, 191 insertions, 145 deletions

diff --git a/intern/cycles/kernel/closure/alloc.h b/intern/cycles/kernel/closure/alloc.h
index 48a60405b5a..b903aeb8073 100644
--- a/intern/cycles/kernel/closure/alloc.h
+++ b/intern/cycles/kernel/closure/alloc.h
@@ -45,7 +45,7 @@ ccl_device ccl_addr_space void *closure_alloc_extra(ShaderData *sd, int size)
 	int num_extra = ((size + sizeof(ShaderClosure) - 1) / sizeof(ShaderClosure));
 
 	if(num_extra > sd->num_closure_left) {
-		/* Remove previous closure. */
+		/* Remove previous closure if it was allocated. */
 		sd->num_closure--;
 		sd->num_closure_left++;
 		return NULL;
diff --git a/intern/cycles/kernel/osl/osl_closures.cpp b/intern/cycles/kernel/osl/osl_closures.cpp
index 68c707e6c3e..e3e85705ebc 100644
--- a/intern/cycles/kernel/osl/osl_closures.cpp
+++ b/intern/cycles/kernel/osl/osl_closures.cpp
@@ -186,22 +186,22 @@ public:
 	MicrofacetBsdf *alloc(ShaderData *sd, int path_flag, float3 weight)
 	{
 		MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
-		MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
-		if(bsdf && extra) {
-			bsdf->extra = extra;
-
-			bsdf->ior = 1.5f;
-
-			bsdf->alpha_x = clearcoat_roughness;
-			bsdf->alpha_y = clearcoat_roughness;
-
-			bsdf->extra->cspec0 = make_float3(0.04f, 0.04f, 0.04f);
-			bsdf->extra->clearcoat = clearcoat;
+		if(!bsdf) {
+			return NULL;
+		}
 
-			return bsdf;
+		MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+		if(!extra) {
+			return NULL;
 		}
 
-		return NULL;
+		bsdf->extra = extra;
+		bsdf->ior = 1.5f;
+		bsdf->alpha_x = clearcoat_roughness;
+		bsdf->alpha_y = clearcoat_roughness;
+		bsdf->extra->cspec0 = make_float3(0.04f, 0.04f, 0.04f);
+		bsdf->extra->clearcoat = clearcoat;
+		return bsdf;
 	}
 
 	void setup(ShaderData *sd, int path_flag, float3 weight)
@@ -359,18 +359,24 @@ public:
 		/* Technically, the MultiGGX Glass closure may also transmit. However,
 		* since this is set statically and only used for caustic flags, this
 		* is probably as good as it gets. */
-		if(!skip(sd, path_flag, LABEL_GLOSSY | LABEL_REFLECT)) {
-			MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
-			MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
-			if(bsdf && extra) {
-				bsdf->extra = extra;
-				bsdf->extra->color = color;
-				bsdf->extra->cspec0 = cspec0;
-				return bsdf;
-			}
+		if(skip(sd, path_flag, LABEL_GLOSSY | LABEL_REFLECT)) {
+			return NULL;
+		}
+
+		MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
+		if(!bsdf) {
+			return NULL;
+		}
+
+		MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+		if(!extra) {
+			return NULL;
 		}
 
-		return NULL;
+		bsdf->extra = extra;
+		bsdf->extra->color = color;
+		bsdf->extra->cspec0 = cspec0;
+		return bsdf;
 	}
 };
 
@@ -437,17 +443,23 @@ public:
 		/* Technically, the MultiGGX closure may also transmit. However,
 		 * since this is set statically and only used for caustic flags, this
 		 * is probably as good as it gets. */
-	    if(!skip(sd, path_flag, LABEL_GLOSSY|LABEL_REFLECT)) {
-			MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
-			MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
-			if(bsdf && extra) {
-				bsdf->extra = extra;
-				bsdf->extra->color = color;
-				return bsdf;
-			}
+	    if(skip(sd, path_flag, LABEL_GLOSSY|LABEL_REFLECT)) {
+			return NULL;
 		}
 
-		return NULL;
+		MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
+		if(!bsdf) {
+			return NULL;
+		}
+
+		MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+		if(!extra) {
+			return NULL;
+		}
+
+		bsdf->extra = extra;
+		bsdf->extra->color = color;
+		return bsdf;
 	}
 };
 
@@ -536,18 +548,24 @@ public:
 		/* Technically, the MultiGGX closure may also transmit. However,
 		* since this is set statically and only used for caustic flags, this
 		* is probably as good as it gets. */
-		if(!skip(sd, path_flag, LABEL_GLOSSY | LABEL_REFLECT)) {
-			MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
-			MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
-			if(bsdf && extra) {
-				bsdf->extra = extra;
-				bsdf->extra->color = color;
-				bsdf->extra->cspec0 = cspec0;
-				return bsdf;
-			}
+		if(skip(sd, path_flag, LABEL_GLOSSY | LABEL_REFLECT)) {
+			return NULL;
+		}
+
+		MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc_osl(sd, sizeof(MicrofacetBsdf), weight, &params);
+		if(!bsdf) {
+			return NULL;
+		}
+
+		MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+		if(!extra) {
+			return NULL;
 		}
 
-		return NULL;
+		bsdf->extra = extra;
+		bsdf->extra->color = color;
+		bsdf->extra->cspec0 = cspec0;
+		return bsdf;
 	}
 };
 
diff --git a/intern/cycles/kernel/svm/svm_closure.h b/intern/cycles/kernel/svm/svm_closure.h
index 4afb91e732b..f04c46ef7f9 100644
--- a/intern/cycles/kernel/svm/svm_closure.h
+++ b/intern/cycles/kernel/svm/svm_closure.h
@@ -269,33 +269,38 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 					float3 spec_weight = weight * specular_weight;
 
 					MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), spec_weight);
+					if(!bsdf){
+						break;
+					}
+
 					MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+					if(!extra) {
+						break;
+					}
 
-					if(bsdf && extra) {
-						bsdf->N = N;
-						bsdf->ior = (2.0f / (1.0f - safe_sqrtf(0.08f * specular))) - 1.0f;
-						bsdf->T = T;
-						bsdf->extra = extra;
+					bsdf->N = N;
+					bsdf->ior = (2.0f / (1.0f - safe_sqrtf(0.08f * specular))) - 1.0f;
+					bsdf->T = T;
+					bsdf->extra = extra;
 
-						float aspect = safe_sqrtf(1.0f - anisotropic * 0.9f);
-						float r2 = roughness * roughness;
+					float aspect = safe_sqrtf(1.0f - anisotropic * 0.9f);
+					float r2 = roughness * roughness;
 
-						bsdf->alpha_x = r2 / aspect;
-						bsdf->alpha_y = r2 * aspect;
+					bsdf->alpha_x = r2 / aspect;
+					bsdf->alpha_y = r2 * aspect;
 
-						float m_cdlum = 0.3f * base_color.x + 0.6f * base_color.y + 0.1f * base_color.z; // luminance approx.
-						float3 m_ctint = m_cdlum > 0.0f ? base_color / m_cdlum : make_float3(0.0f, 0.0f, 0.0f); // normalize lum. to isolate hue+sat
-						float3 tmp_col = make_float3(1.0f, 1.0f, 1.0f) * (1.0f - specular_tint) + m_ctint * specular_tint;
+					float m_cdlum = 0.3f * base_color.x + 0.6f * base_color.y + 0.1f * base_color.z; // luminance approx.
+					float3 m_ctint = m_cdlum > 0.0f ? base_color / m_cdlum : make_float3(0.0f, 0.0f, 0.0f); // normalize lum. to isolate hue+sat
+					float3 tmp_col = make_float3(1.0f, 1.0f, 1.0f) * (1.0f - specular_tint) + m_ctint * specular_tint;
 
-						bsdf->extra->cspec0 = (specular * 0.08f * tmp_col) * (1.0f - metallic) + base_color * metallic;
-						bsdf->extra->color = base_color;
+					bsdf->extra->cspec0 = (specular * 0.08f * tmp_col) * (1.0f - metallic) + base_color * metallic;
+					bsdf->extra->color = base_color;
 
-						/* setup bsdf */
-						if(distribution == CLOSURE_BSDF_MICROFACET_GGX_GLASS_ID || roughness <= 0.075f) /* use single-scatter GGX */
-							sd->flag |= bsdf_microfacet_ggx_aniso_fresnel_setup(bsdf, sd);
-						else /* use multi-scatter GGX */
-							sd->flag |= bsdf_microfacet_multi_ggx_aniso_fresnel_setup(bsdf, sd);
-					}
+					/* setup bsdf */
+					if(distribution == CLOSURE_BSDF_MICROFACET_GGX_GLASS_ID || roughness <= 0.075f) /* use single-scatter GGX */
+						sd->flag |= bsdf_microfacet_ggx_aniso_fresnel_setup(bsdf, sd);
+					else /* use multi-scatter GGX */
+						sd->flag |= bsdf_microfacet_multi_ggx_aniso_fresnel_setup(bsdf, sd);
 				}
 #ifdef __CAUSTICS_TRICKS__
 			}
@@ -318,22 +323,27 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 #endif
 						{
 							MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), glass_weight*fresnel);
+							if(!bsdf) {
+								break;
+							}
+
 							MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+							if(!extra) {
+								break;
+							}
 
-							if(bsdf && extra) {
-								bsdf->N = N;
-								bsdf->extra = extra;
+							bsdf->N = N;
+							bsdf->extra = extra;
 
-								bsdf->alpha_x = refl_roughness * refl_roughness;
-								bsdf->alpha_y = refl_roughness * refl_roughness;
-								bsdf->ior = ior;
+							bsdf->alpha_x = refl_roughness * refl_roughness;
+							bsdf->alpha_y = refl_roughness * refl_roughness;
+							bsdf->ior = ior;
 
-								bsdf->extra->color = base_color;
-								bsdf->extra->cspec0 = cspec0;
+							bsdf->extra->color = base_color;
+							bsdf->extra->cspec0 = cspec0;
 
-								/* setup bsdf */
-								sd->flag |= bsdf_microfacet_ggx_fresnel_setup(bsdf, sd);
-							}
+							/* setup bsdf */
+							sd->flag |= bsdf_microfacet_ggx_fresnel_setup(bsdf, sd);
 						}
 
 						/* refraction */
@@ -342,43 +352,49 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 #endif
 						{
 							MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), base_color*glass_weight*(1.0f - fresnel));
+							if(!bsdf) {
+								break;
+							}
 
-							if(bsdf) {
-								bsdf->N = N;
+							bsdf->N = N;
 
-								if(distribution == CLOSURE_BSDF_MICROFACET_GGX_GLASS_ID)
-									transmission_roughness = 1.0f - (1.0f - refl_roughness) * (1.0f - transmission_roughness);
-								else
-									transmission_roughness = refl_roughness;
+							if(distribution == CLOSURE_BSDF_MICROFACET_GGX_GLASS_ID)
+								transmission_roughness = 1.0f - (1.0f - refl_roughness) * (1.0f - transmission_roughness);
+							else
+								transmission_roughness = refl_roughness;
 
-								bsdf->alpha_x = transmission_roughness * transmission_roughness;
-								bsdf->alpha_y = transmission_roughness * transmission_roughness;
-								bsdf->ior = ior;
+							bsdf->alpha_x = transmission_roughness * transmission_roughness;
+							bsdf->alpha_y = transmission_roughness * transmission_roughness;
+							bsdf->ior = ior;
 
-								/* setup bsdf */
-								sd->flag |= bsdf_microfacet_ggx_refraction_setup(bsdf);
-							}
+							/* setup bsdf */
+							sd->flag |= bsdf_microfacet_ggx_refraction_setup(bsdf);
 						}
 					}
 					else { /* use multi-scatter GGX */
 						MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), glass_weight);
+						if(!bsdf) {
+							break;
+						}
+
 						MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+						if(!extra) {
+							break;
+						}
 
-						if(bsdf && extra) {
-							bsdf->N = N;
-							bsdf->extra = extra;
-							bsdf->T = make_float3(0.0f, 0.0f, 0.0f);
+						bsdf->N = N;
+						bsdf->extra = extra;
+						bsdf->T = make_float3(0.0f, 0.0f, 0.0f);
 
-							bsdf->alpha_x = roughness * roughness;
-							bsdf->alpha_y = roughness * roughness;
-							bsdf->ior = ior;
+						bsdf->alpha_x = roughness * roughness;
+						bsdf->alpha_y = roughness * roughness;
+						bsdf->ior = ior;
 
-							bsdf->extra->color = base_color;
-							bsdf->extra->cspec0 = cspec0;
+						bsdf->extra->color = base_color;
+						bsdf->extra->cspec0 = cspec0;
 
-							/* setup bsdf */
-							sd->flag |= bsdf_microfacet_multi_ggx_glass_fresnel_setup(bsdf, sd);
-						}
+						/* setup bsdf */
+						sd->flag |= bsdf_microfacet_multi_ggx_glass_fresnel_setup(bsdf, sd);
 					}
 				}
 #ifdef __CAUSTICS_TRICKS__
@@ -391,22 +407,27 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 #endif
 				if(clearcoat > CLOSURE_WEIGHT_CUTOFF) {
 					MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), weight);
+					if(!bsdf) {
+						break;
+					}
+
 					MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+					if(!extra) {
+						break;
+					}
 
-					if(bsdf && extra) {
-						bsdf->N = clearcoat_normal;
-						bsdf->ior = 1.5f;
-						bsdf->extra = extra;
+					bsdf->N = clearcoat_normal;
+					bsdf->ior = 1.5f;
+					bsdf->extra = extra;
 
-						bsdf->alpha_x = clearcoat_roughness * clearcoat_roughness;
-						bsdf->alpha_y = clearcoat_roughness * clearcoat_roughness;
+					bsdf->alpha_x = clearcoat_roughness * clearcoat_roughness;
+					bsdf->alpha_y = clearcoat_roughness * clearcoat_roughness;
 
-						bsdf->extra->cspec0 = make_float3(0.04f, 0.04f, 0.04f);
-						bsdf->extra->clearcoat = clearcoat;
+					bsdf->extra->cspec0 = make_float3(0.04f, 0.04f, 0.04f);
+					bsdf->extra->clearcoat = clearcoat;
 
-						/* setup bsdf */
-						sd->flag |= bsdf_microfacet_ggx_clearcoat_setup(bsdf, sd);
-					}
+					/* setup bsdf */
+					sd->flag |= bsdf_microfacet_ggx_clearcoat_setup(bsdf, sd);
 				}
 #ifdef __CAUSTICS_TRICKS__
 			}
@@ -461,30 +482,33 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 			float3 weight = sd->svm_closure_weight * mix_weight;
 			MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), weight);
 
-			if(bsdf) {
-				bsdf->N = N;
-				bsdf->alpha_x = param1;
-				bsdf->alpha_y = param1;
-				bsdf->ior = 0.0f;
-				bsdf->extra = NULL;
+			if(!bsdf) {
+				break;
+			}
 
-				/* setup bsdf */
-				if(type == CLOSURE_BSDF_REFLECTION_ID)
-					sd->flag |= bsdf_reflection_setup(bsdf);
-				else if(type == CLOSURE_BSDF_MICROFACET_BECKMANN_ID)
-					sd->flag |= bsdf_microfacet_beckmann_setup(bsdf);
-				else if(type == CLOSURE_BSDF_MICROFACET_GGX_ID)
-					sd->flag |= bsdf_microfacet_ggx_setup(bsdf);
-				else if(type == CLOSURE_BSDF_MICROFACET_MULTI_GGX_ID) {
-					kernel_assert(stack_valid(data_node.z));
-					bsdf->extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
-					if(bsdf->extra) {
-						bsdf->extra->color = stack_load_float3(stack, data_node.z);
-						sd->flag |= bsdf_microfacet_multi_ggx_setup(bsdf);
-					}
+			bsdf->N = N;
+			bsdf->alpha_x = param1;
+			bsdf->alpha_y = param1;
+			bsdf->ior = 0.0f;
+			bsdf->extra = NULL;
+
+			/* setup bsdf */
+			if(type == CLOSURE_BSDF_REFLECTION_ID)
+				sd->flag |= bsdf_reflection_setup(bsdf);
+			else if(type == CLOSURE_BSDF_MICROFACET_BECKMANN_ID)
+				sd->flag |= bsdf_microfacet_beckmann_setup(bsdf);
+			else if(type == CLOSURE_BSDF_MICROFACET_GGX_ID)
+				sd->flag |= bsdf_microfacet_ggx_setup(bsdf);
+			else if(type == CLOSURE_BSDF_MICROFACET_MULTI_GGX_ID) {
+				kernel_assert(stack_valid(data_node.z));
+				bsdf->extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+				if(bsdf->extra) {
+					bsdf->extra->color = stack_load_float3(stack, data_node.z);
+					sd->flag |= bsdf_microfacet_multi_ggx_setup(bsdf);
 				}
-				else
-					sd->flag |= bsdf_ashikhmin_shirley_setup(bsdf);
+			}
+			else {
+				sd->flag |= bsdf_ashikhmin_shirley_setup(bsdf);
 			}
 
 			break;
@@ -586,25 +610,29 @@ ccl_device void svm_node_closure_bsdf(KernelGlobals *kg, ShaderData *sd, float *
 #endif
 			float3 weight = sd->svm_closure_weight * mix_weight;
 			MicrofacetBsdf *bsdf = (MicrofacetBsdf*)bsdf_alloc(sd, sizeof(MicrofacetBsdf), weight);
-			MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+			if(!bsdf) {
+				break;
+			}
 
-			if(bsdf && extra) {
-				bsdf->N = N;
-				bsdf->extra = extra;
-				bsdf->T = make_float3(0.0f, 0.0f, 0.0f);
+			MicrofacetExtra *extra = (MicrofacetExtra*)closure_alloc_extra(sd, sizeof(MicrofacetExtra));
+			if(!extra) {
+				break;
+			}
 
-				bsdf->alpha_x = param1;
-				bsdf->alpha_y = param1;
-				float eta = fmaxf(param2, 1e-5f);
-				bsdf->ior = (sd->flag & SD_BACKFACING)? 1.0f/eta: eta;
+			bsdf->N = N;
+			bsdf->extra = extra;
+			bsdf->T = make_float3(0.0f, 0.0f, 0.0f);
 
-				kernel_assert(stack_valid(data_node.z));
-				bsdf->extra->color = stack_load_float3(stack, data_node.z);
+			bsdf->alpha_x = param1;
+			bsdf->alpha_y = param1;
+			float eta = fmaxf(param2, 1e-5f);
+			bsdf->ior = (sd->flag & SD_BACKFACING)? 1.0f/eta: eta;
 
-				/* setup bsdf */
-				sd->flag |= bsdf_microfacet_multi_ggx_glass_setup(bsdf);
-			}
+			kernel_assert(stack_valid(data_node.z));
+			bsdf->extra->color = stack_load_float3(stack, data_node.z);
 
+			/* setup bsdf */
+			sd->flag |= bsdf_microfacet_multi_ggx_glass_setup(bsdf);
 			break;
 		}
 		case CLOSURE_BSDF_MICROFACET_BECKMANN_ANISO_ID: