Add LSS intrinsics (#7200)

* WiP: LSS intrinsics: initial commit

* format code

* Fix CI failures

* Address review comment

---------

Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>

2 files changed, 220 insertions, 0 deletions

diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang
index fd7c7cfc7..9b15392ec 100644
--- a/source/slang/hlsl.meta.slang
+++ b/source/slang/hlsl.meta.slang
@@ -17948,6 +17948,114 @@ int GetClusterID()
         };
     }
 }
+
+/// @category raytracing
+[__requiresNVAPI]
+[NonUniformReturn]
+[require(cuda_hlsl_spirv, raytracing_lss)]
+float4 GetSpherePositionAndRadius()
+{
+    __target_switch
+    {
+    case hlsl: __intrinsic_asm "NvRtSphereObjectPositionAndRadius";
+    case cuda:
+        {
+            __intrinsic_asm "optixGetSpherePositionAndRadius";
+        }
+    case spirv:
+        return spirv_asm
+        {
+            OpExtension "SPV_NV_linear_swept_spheres";
+            OpCapability RayTracingLinearSweptSpheresGeometryNV;
+            OpCapability RayTracingSpheresGeometryNV;
+            %pos:$$float3 = OpLoad builtin(HitSpherePositionNV:float3);
+            %rad:$$float = OpLoad builtin(HitSphereRadiusNV:float);
+            result:$$float4 = OpCompositeConstruct %pos %rad;
+        };
+    }
+}
+
+/// @category raytracing
+[__requiresNVAPI]
+[NonUniformReturn]
+[require(cuda_hlsl_spirv, raytracing_lss)]
+float2x4 GetLssPositionsAndRadii()
+{
+    __target_switch
+    {
+    case hlsl: __intrinsic_asm "NvRtLssObjectPositionsAndRadii";
+    case cuda:
+        {
+            __intrinsic_asm "optixObjectPositionsAndRadii";
+        }
+    case spirv:
+        return spirv_asm
+        {
+            OpExtension "SPV_NV_linear_swept_spheres";
+            OpCapability RayTracingLinearSweptSpheresGeometryNV;
+            OpCapability RayTracingSpheresGeometryNV;
+            %positions:$$float3[2] = OpLoad builtin(HitLSSPositionsNV:float3[2]);
+            %radii:$$float[2] = OpLoad builtin(HitLSSRadiiNV:float[2]);
+            %r0:$$float = OpCompositeExtract %radii 0;
+            %r1:$$float = OpCompositeExtract %radii 1;
+            %p0:$$float3 = OpCompositeExtract %positions 0;
+            %p1:$$float3 = OpCompositeExtract %positions 1;
+            %a:$$float4 = OpCompositeConstruct %p0 %r0;
+            %b:$$float4 = OpCompositeConstruct %p1 %r1;
+            result:$$float2x4 = OpCompositeConstruct %a %b;
+        };
+    
+    }
+}
+
+/// @category raytracing
+[__requiresNVAPI]
+[NonUniformReturn]
+[require(cuda_hlsl_spirv, raytracing_lss)]
+bool IsSphereHit()
+{
+    __target_switch
+    {
+    case hlsl: __intrinsic_asm "NvRtIsSphereHit";
+    case cuda:
+        {
+            __intrinsic_asm "optixIsSphereHit";
+        }
+    case spirv:
+        return spirv_asm
+        {
+            OpExtension "SPV_NV_linear_swept_spheres";
+            OpCapability RayTracingLinearSweptSpheresGeometryNV;
+            OpCapability RayTracingSpheresGeometryNV;
+            result:$$bool = OpLoad builtin(HitIsSphereNV:bool);
+        };
+    }
+}
+
+/// @category raytracing
+[__requiresNVAPI]
+[NonUniformReturn]
+[require(cuda_hlsl_spirv, raytracing_lss)]
+bool IsLssHit()
+{
+    __target_switch
+    {
+    case hlsl: __intrinsic_asm "NvRtIsLssHit";
+    case cuda:
+        {
+            __intrinsic_asm "optixIsLSSHit";
+        }
+    case spirv:
+        return spirv_asm
+        {
+            OpExtension "SPV_NV_linear_swept_spheres";
+            OpCapability RayTracingLinearSweptSpheresGeometryNV;
+            OpCapability RayTracingSpheresGeometryNV;
+            result:$$bool = OpLoad builtin(HitIsLSSNV:bool);
+        };
+    }
+}
+
 // Note: The provisional DXR spec included these unadorned
 // `ObjectToWorld()` and `WorldToObject()` functions, so
 // we will forward them to the new names as a convience
@@ -20529,6 +20637,106 @@ struct HitObject
     }
 
     [__requiresNVAPI]
+    [NonUniformReturn]
+    [require(cuda_hlsl_spirv, raytracing_lss)]
+    float4 GetSpherePositionAndRadius()
+    {
+        __target_switch
+        {
+        case hlsl: __intrinsic_asm "NvRtSphereObjectPositionAndRadius";
+        case cuda:
+            {
+                __intrinsic_asm "optixHitObjectGetSpherePositionAndRadius";
+            }
+        case spirv:
+            return spirv_asm
+            {
+                OpExtension "SPV_NV_linear_swept_spheres";
+                OpCapability RayTracingLinearSweptSpheresGeometryNV;
+                OpCapability RayTracingSpheresGeometryNV;
+                %position:$$float3 = OpHitObjectGetSpherePositionNV &this;
+                %radius:$$float = OpHitObjectGetSphereRadiusNV &this;
+                result:$$float4 = OpCompositeConstruct %position %radius;
+            };
+        }
+    }
+
+    [__requiresNVAPI]
+    [NonUniformReturn]
+    [require(cuda_hlsl_spirv, raytracing_lss)]
+    float2x4 GetLssPositionsAndRadii()
+    {
+        __target_switch
+        {
+        case hlsl: __intrinsic_asm "NvRtLssObjectPositionsAndRadii";
+        case cuda:
+            {
+                __intrinsic_asm "optixHitObjectGetSpherePositionAndRadius";
+            }
+        case spirv:
+            return spirv_asm
+            {
+                OpExtension "SPV_NV_linear_swept_spheres";
+                OpCapability RayTracingLinearSweptSpheresGeometryNV;
+                OpCapability RayTracingSpheresGeometryNV;
+                %positions:$$float3[2] = OpHitObjectGetLSSPositionsNV &this;
+                %radii:$$float[2] = OpHitObjectGetLSSRadiiNV &this;
+                %r0:$$float = OpCompositeExtract %radii 0;
+                %r1:$$float = OpCompositeExtract %radii 1;
+                %p0:$$float3 = OpCompositeExtract %positions 0;
+                %p1:$$float3 = OpCompositeExtract %positions 1;
+                %a:$$float4 = OpCompositeConstruct %p0 %r0;
+                %b:$$float4 = OpCompositeConstruct %p1 %r1;
+                result:$$float2x4 = OpCompositeConstruct %a %b;
+            };
+        }
+    }
+
+    [__requiresNVAPI]
+    [NonUniformReturn]
+    [require(cuda_hlsl_spirv, raytracing_lss)]
+    bool IsSphereHit()
+    {
+        __target_switch
+        {
+        case hlsl: __intrinsic_asm "NvRtIsSphereHit";
+        case cuda:
+            {
+                __intrinsic_asm "optixHitObjectIsSphereHit";
+            }
+        case spirv:
+            return spirv_asm
+            {
+                OpExtension "SPV_NV_linear_swept_spheres";
+                OpCapability RayTracingLinearSweptSpheresGeometryNV;
+                result:$$bool = OpHitObjectIsSphereHitNV &this;
+            };
+        }
+    }
+
+    [__requiresNVAPI]
+    [NonUniformReturn]
+    [require(cuda_hlsl_spirv, raytracing_lss)]
+    bool IsLssHit()
+    {
+        __target_switch
+        {
+        case hlsl: __intrinsic_asm "NvRtIsLssHit";
+        case cuda:
+            {
+                __intrinsic_asm "optixHitObjectIsLSSHit";
+            }
+        case spirv:
+            return spirv_asm
+            {
+                OpExtension "SPV_NV_linear_swept_spheres";
+                OpCapability RayTracingLinearSweptSpheresGeometryNV;
+                result:$$bool = OpHitObjectIsLSSHitNV &this;
+            };
+        }
+    }
+
+    [__requiresNVAPI]
     __glsl_extension(GL_EXT_ray_tracing)
     [ForceInline]
     [require(glsl_hlsl_spirv, ser_raygen_closesthit_miss)]
diff --git a/source/slang/slang-capabilities.capdef b/source/slang/slang-capabilities.capdef
index 48617c54d..28fa211e4 100644
--- a/source/slang/slang-capabilities.capdef
+++ b/source/slang/slang-capabilities.capdef
@@ -547,6 +547,10 @@ def SPV_NV_shader_invocation_reorder : _spirv_1_5 + SPV_KHR_ray_tracing;
 /// [EXT]
 def SPV_NV_cluster_acceleration_structure : _spirv_1_0;
 
+/// Represents the SPIR-V extension for linear swept spheres.
+/// [EXT]
+def SPV_NV_linear_swept_spheres : _spirv_1_0;
+
 /// Represents the SPIR-V extension for shader image footprint.
 /// [EXT]
 def SPV_NV_shader_image_footprint : _spirv_1_0;
@@ -714,6 +718,10 @@ def spvShaderInvocationReorderNV : SPV_NV_shader_invocation_reorder;
 /// [EXT]
 def spvRayTracingClusterAccelerationStructureNV : SPV_NV_cluster_acceleration_structure;
 
+/// Represents the SPIR-V capability for cluster acceleration structure.
+/// [EXT]
+def spvRayTracingLinearSweptSpheresGeometryNV : SPV_NV_linear_swept_spheres;
+
 /// Represents the SPIR-V capability for shader clock.
 /// [EXT]
 def spvShaderClockKHR : SPV_KHR_shader_clock;
@@ -2246,6 +2254,10 @@ alias raytracing_intersection = intersection + raytracing;
 /// [Compound]
 alias raytracing_anyhit_closesthit = anyhit_closesthit + raytracing;
 
+/// Collection of capabilities for linear swept spheres.
+/// [Compound]
+alias raytracing_lss = raytracing_anyhit_closesthit | spvRayTracingLinearSweptSpheresGeometryNV;
+
 /// Collection of capabilities for raytracing with the shader stages of anyhit, closesthit, and intersection.
 /// [Compound]
 alias raytracing_anyhit_closesthit_intersection = anyhit_closesthit_intersection + raytracing;