Adds SPV_KHR_shader_draw_parameter extension functionality for SPIR-V.

SPIRV/GlslangToSpv.cpp

@@ -497,12 +497,21 @@ spv::BuiltIn TGlslangToSpvTraverser::TranslateBuiltInDecoration(glslang::TBuiltI
     case glslang::EbvInstanceId:           return spv::BuiltInInstanceId;
     case glslang::EbvVertexIndex:          return spv::BuiltInVertexIndex;
     case glslang::EbvInstanceIndex:        return spv::BuiltInInstanceIndex;
-    case glslang::EbvBaseVertex:
-    case glslang::EbvBaseInstance:
-    case glslang::EbvDrawId:
         // TODO: Add SPIR-V builtin ID.
         logger->missingFunctionality("shader draw parameters");
         return spv::BuiltInMax;
+    case glslang::EbvDrawId:
+        builder.addCapability(spv::CapabilityDrawParameters);
+        return spv::BuiltInDrawIndex;
+
+    case glslang::EbvBaseVertex:
+        builder.addCapability(spv::CapabilityDrawParameters);
+        return spv::BuiltInBaseVertex;
+
+    case glslang::EbvBaseInstance:
+        builder.addCapability(spv::CapabilityDrawParameters);
+        return spv::BuiltInBaseInstance;
+
     case glslang::EbvPrimitiveId:          return spv::BuiltInPrimitiveId;
     case glslang::EbvInvocationId:         return spv::BuiltInInvocationId;
     case glslang::EbvTessLevelInner:       return spv::BuiltInTessLevelInner;

SPIRV/doc.cpp

@@ -309,6 +309,9 @@ const char* BuiltInString(int builtIn)
     case 41: return "SubgroupLocalInvocationId";
     case 42: return "VertexIndex";                 // TBD: put next to VertexId?
     case 43: return "InstanceIndex";               // TBD: put next to InstanceId?
+    case 4424: return "BaseVertex";
+    case 4425: return "BaseInstance";
+    case 4426: return "DrawIndex";
 
     case BuiltInCeiling:
     default: return "Bad";
@@ -803,6 +806,7 @@ const char* CapabilityString(int info)
     case 55: return "StorageImageReadWithoutFormat";
     case 56: return "StorageImageWriteWithoutFormat";
     case 57: return "MultiViewport";
+    case 4427: return "DrawParameters";
 
     case CapabilityCeiling:
     default: return "Bad";

SPIRV/spirv.hpp

@@ -420,6 +420,9 @@ enum BuiltIn {
     BuiltInSubgroupLocalInvocationId = 41,
     BuiltInVertexIndex = 42,
     BuiltInInstanceIndex = 43,
+    BuiltInBaseVertex = 4424,
+    BuiltInBaseInstance = 4425,
+    BuiltInDrawIndex = 4426,
     BuiltInMax = 0x7fffffff,
 };
 
@@ -595,6 +598,7 @@ enum Capability {
     CapabilityStorageImageReadWithoutFormat = 55,
     CapabilityStorageImageWriteWithoutFormat = 56,
     CapabilityMultiViewport = 57,
+    CapabilityDrawParameters = 4427,
     CapabilityMax = 0x7fffffff,
 };
 

Test/baseResults/spv.drawParams.vert.out

+spv.drawParams.vert
+Warning, version 450 is not yet complete; most version-specific features are present, but some are missing.
+
+Shader version: 450
+Requested GL_ARB_shader_draw_parameters
+0:? Sequence
+0:7  Function Definition: main( (global void)
+0:7    Function Parameters: 
+0:9    Sequence
+0:9      Sequence
+0:9        move second child to first child (temp int)
+0:9          'a' (temp int)
+0:9          'gl_BaseVertexARB' (in int BaseVertex)
+0:10      Sequence
+0:10        move second child to first child (temp int)
+0:10          'b' (temp int)
+0:10          'gl_BaseInstanceARB' (in int BaseInstance)
+0:11      Sequence
+0:11        move second child to first child (temp int)
+0:11          'c' (temp int)
+0:11          'gl_DrawIDARB' (in int DrawId)
+0:12      move second child to first child (temp 3-component vector of float)
+0:12        'pos' (smooth out 3-component vector of float)
+0:12        Construct vec3 (temp 3-component vector of float)
+0:12          Convert int to float (temp float)
+0:12            'a' (temp int)
+0:12          Convert int to float (temp float)
+0:12            'b' (temp int)
+0:12          Convert int to float (temp float)
+0:12            'c' (temp int)
+0:?   Linker Objects
+0:?     'pos' (smooth out 3-component vector of float)
+0:?     'gl_VertexID' (gl_VertexId int VertexId)
+0:?     'gl_InstanceID' (gl_InstanceId int InstanceId)
+
+
+Linked vertex stage:
+
+
+Shader version: 450
+Requested GL_ARB_shader_draw_parameters
+0:? Sequence
+0:7  Function Definition: main( (global void)
+0:7    Function Parameters: 
+0:9    Sequence
+0:9      Sequence
+0:9        move second child to first child (temp int)
+0:9          'a' (temp int)
+0:9          'gl_BaseVertexARB' (in int BaseVertex)
+0:10      Sequence
+0:10        move second child to first child (temp int)
+0:10          'b' (temp int)
+0:10          'gl_BaseInstanceARB' (in int BaseInstance)
+0:11      Sequence
+0:11        move second child to first child (temp int)
+0:11          'c' (temp int)
+0:11          'gl_DrawIDARB' (in int DrawId)
+0:12      move second child to first child (temp 3-component vector of float)
+0:12        'pos' (smooth out 3-component vector of float)
+0:12        Construct vec3 (temp 3-component vector of float)
+0:12          Convert int to float (temp float)
+0:12            'a' (temp int)
+0:12          Convert int to float (temp float)
+0:12            'b' (temp int)
+0:12          Convert int to float (temp float)
+0:12            'c' (temp int)
+0:?   Linker Objects
+0:?     'pos' (smooth out 3-component vector of float)
+0:?     'gl_VertexID' (gl_VertexId int VertexId)
+0:?     'gl_InstanceID' (gl_InstanceId int InstanceId)
+

Test/spv.drawParams.vert

+#version 450
+
+#extension GL_ARB_shader_draw_parameters : enable
+
+out vec3 pos;
+
+void main()
+{
+    int a = gl_BaseVertexARB;
+    int b = gl_BaseInstanceARB;
+    int c = gl_DrawIDARB;
+    pos = vec3(a, b, c);
+}