Implement GL_EXT_terminate_invocation (#2454)

SPIRV/GLSL.ext.KHR.h

@@ -49,4 +49,6 @@ static const char* const E_SPV_KHR_non_semantic_info            = "SPV_KHR_non_s
 static const char* const E_SPV_KHR_ray_tracing                  = "SPV_KHR_ray_tracing";
 static const char* const E_SPV_KHR_ray_query                    = "SPV_KHR_ray_query";
 static const char* const E_SPV_KHR_fragment_shading_rate        = "SPV_KHR_fragment_shading_rate";
+static const char* const E_SPV_KHR_terminate_invocation         = "SPV_KHR_terminate_invocation";
+
 #endif  // #ifndef GLSLextKHR_H

SPIRV/GlslangToSpv.cpp

@@ -3458,6 +3458,10 @@ bool TGlslangToSpvTraverser::visitBranch(glslang::TVisit /* visit */, glslang::T
     case glslang::EOpKill:
         builder.makeDiscard();
         break;
+    case glslang::EOpTerminateInvocation:
+        builder.addExtension(spv::E_SPV_KHR_terminate_invocation);
+        builder.makeTerminateInvocation();
+        break;
     case glslang::EOpBreak:
         if (breakForLoop.top())
             builder.createLoopExit();

SPIRV/SpvBuilder.cpp

@@ -1454,6 +1454,13 @@ void Builder::makeDiscard()
 }
 
 // Comments in header
+void Builder::makeTerminateInvocation()
+{
+    buildPoint->addInstruction(std::unique_ptr<Instruction>(new Instruction(OpTerminateInvocation)));
+    createAndSetNoPredecessorBlock("post-terminate-invocation");
+}
+
+// Comments in header
 Id Builder::createVariable(Decoration precision, StorageClass storageClass, Id type, const char* name, Id initializer)
 {
     Id pointerType = makePointer(storageClass, type);

SPIRV/SpvBuilder.h

@@ -357,8 +357,9 @@ public:
     // Generate all the code needed to finish up a function.
     void leaveFunction();
 
-    // Create a discard.
+    // Create a discard or terminate-invocation.
     void makeDiscard();
+    void makeTerminateInvocation();
 
     // Create a global or function local or IO variable.
     Id createVariable(Decoration precision, StorageClass, Id type, const char* name = nullptr,

SPIRV/doc.cpp

@@ -1336,6 +1336,8 @@ const char* OpcodeString(int op)
     case 365: return "OpGroupNonUniformQuadBroadcast";
     case 366: return "OpGroupNonUniformQuadSwap";
 
+    case OpTerminateInvocation: return "OpTerminateInvocation";
+
     case 4421: return "OpSubgroupBallotKHR";
     case 4422: return "OpSubgroupFirstInvocationKHR";
     case 4428: return "OpSubgroupAllKHR";
@@ -1504,6 +1506,7 @@ void Parameterize()
     InstructionDesc[OpBranchConditional].setResultAndType(false, false);
     InstructionDesc[OpSwitch].setResultAndType(false, false);
     InstructionDesc[OpKill].setResultAndType(false, false);
+    InstructionDesc[OpTerminateInvocation].setResultAndType(false, false);
     InstructionDesc[OpReturn].setResultAndType(false, false);
     InstructionDesc[OpReturnValue].setResultAndType(false, false);
     InstructionDesc[OpUnreachable].setResultAndType(false, false);

SPIRV/spirv.hpp

@@ -1849,6 +1849,7 @@ inline void HasResultAndType(Op opcode, bool *hasResult, bool *hasResultType) {
     case OpBranchConditional: *hasResult = false; *hasResultType = false; break;
     case OpSwitch: *hasResult = false; *hasResultType = false; break;
     case OpKill: *hasResult = false; *hasResultType = false; break;
+    case OpTerminateInvocation: *hasResult = false; *hasResultType = false; break;
     case OpReturn: *hasResult = false; *hasResultType = false; break;
     case OpReturnValue: *hasResult = false; *hasResultType = false; break;
     case OpUnreachable: *hasResult = false; *hasResultType = false; break;

SPIRV/spvIR.h

@@ -263,6 +263,7 @@ public:
         case OpBranchConditional:
         case OpSwitch:
         case OpKill:
+        case OpTerminateInvocation:
         case OpReturn:
         case OpReturnValue:
         case OpUnreachable:

Test/baseResults/cppDeepNest.frag.out

 cppDeepNest.frag
 ERROR: 0:66: '#if/#ifdef/#ifndef' : maximum nesting depth exceeded 
 ERROR: 0:66: '' : missing #endif 
-ERROR: 0:66: '' :  syntax error, unexpected $end
+ERROR: 0:66: '' :  syntax error, unexpected end of file
 ERROR: 3 compilation errors.  No code generated.
 
 

Test/baseResults/numeral.frag.out

@@ -12,7 +12,7 @@ ERROR: 0:88: '' : float literal needs a decimal point or exponent
 ERROR: 0:98: '' : numeric literal too big 
 ERROR: 0:101: '' : numeric literal too big 
 ERROR: 0:104: '#' : preprocessor directive cannot be preceded by another token 
-ERROR: 0:104: '' :  syntax error, unexpected $end, expecting COMMA or SEMICOLON
+ERROR: 0:104: '' :  syntax error, unexpected end of file, expecting COMMA or SEMICOLON
 ERROR: 14 compilation errors.  No code generated.
 
 

Test/baseResults/spv.terminate.frag.out

+spv.terminate.frag
+// Module Version 10000
+// Generated by (magic number): 8000a
+// Id's are bound by 7
+
+                              Capability Shader
+                              Extension  "SPV_KHR_terminate_invocation"
+               1:             ExtInstImport  "GLSL.std.450"
+                              MemoryModel Logical GLSL450
+                              EntryPoint Fragment 4  "main"
+                              ExecutionMode 4 OriginUpperLeft
+                              Source GLSL 400
+                              SourceExtension  "GL_EXT_terminate_invocation"
+                              Name 4  "main"
+               2:             TypeVoid
+               3:             TypeFunction 2
+         4(main):           2 Function None 3
+               5:             Label
+                              TerminateInvocation
+                              FunctionEnd

Test/baseResults/terminate.frag.out

+terminate.frag
+ERROR: 0:3: 'terminateInvocation' : undeclared identifier 
+ERROR: 0:9: '' :  syntax error, unexpected TERMINATE_INVOCATION, expecting COMMA or SEMICOLON
+ERROR: 2 compilation errors.  No code generated.
+
+
+Shader version: 400
+Requested GL_EXT_terminate_invocation
+ERROR: node is still EOpNull!
+0:3  Function Definition: foo( ( global void)
+0:3    Function Parameters: 
+0:3    Sequence
+0:3      'terminateInvocation' ( temp float)
+0:?   Linker Objects
+
+
+Linked fragment stage:
+
+
+Shader version: 400
+Requested GL_EXT_terminate_invocation
+ERROR: node is still EOpNull!
+0:?   Linker Objects
+

Test/baseResults/terminate.vert.out

+terminate.vert
+ERROR: 0:3: 'terminateInvocation' : undeclared identifier 
+ERROR: 0:9: 'terminateInvocation' : not supported in this stage: vertex
+ERROR: 2 compilation errors.  No code generated.
+
+
+Shader version: 400
+Requested GL_EXT_terminate_invocation
+ERROR: node is still EOpNull!
+0:3  Function Definition: foo( ( global void)
+0:3    Function Parameters: 
+0:3    Sequence
+0:3      'terminateInvocation' ( temp float)
+0:7  Function Definition: main( ( global void)
+0:7    Function Parameters: 
+0:9    Sequence
+0:9      Branch: TerminateInvocation
+0:?   Linker Objects
+0:?     'gl_VertexID' ( gl_VertexId int VertexId)
+0:?     'gl_InstanceID' ( gl_InstanceId int InstanceId)
+
+
+Linked vertex stage:
+
+
+Shader version: 400
+Requested GL_EXT_terminate_invocation
+ERROR: node is still EOpNull!
+0:7  Function Definition: main( ( global void)
+0:7    Function Parameters: 
+0:9    Sequence
+0:9      Branch: TerminateInvocation
+0:?   Linker Objects
+0:?     'gl_VertexID' ( gl_VertexId int VertexId)
+0:?     'gl_InstanceID' ( gl_InstanceId int InstanceId)
+

Test/spv.terminate.frag

+#version 400
+
+#extension GL_EXT_terminate_invocation : enable
+
+void main()
+{
+    terminateInvocation;
+}

Test/terminate.frag

+#version 400
+
+void foo() { terminateInvocation; } // ERROR: identifier undeclared
+
+#extension GL_EXT_terminate_invocation : enable
+
+void main()
+{
+    int terminateInvocation;  // syntax ERROR
+}

Test/terminate.vert

+#version 400
+
+void foo() { terminateInvocation; } // ERROR: identifier undeclared
+
+#extension GL_EXT_terminate_invocation : enable
+
+void main()
+{
+    terminateInvocation;  // ERROR: wrong stage
+}

glslang/Include/intermediate.h

@@ -628,13 +628,14 @@ enum TOperator {
     // Branch
     //
 
-    EOpKill,            // Fragment only
+    EOpKill,                // Fragment only
+    EOpTerminateInvocation, // Fragment only
+    EOpDemote,              // Fragment only
     EOpReturn,
     EOpBreak,
     EOpContinue,
     EOpCase,
     EOpDefault,
-    EOpDemote,          // Fragment only
 
     //
     // Constructors

glslang/MachineIndependent/Scan.cpp

@@ -365,6 +365,7 @@ void TScanContext::fillInKeywordMap()
     (*KeywordMap)["if"] =                      IF;
     (*KeywordMap)["else"] =                    ELSE;
     (*KeywordMap)["discard"] =                 DISCARD;
+    (*KeywordMap)["terminateInvocation"] =     TERMINATE_INVOCATION;
     (*KeywordMap)["return"] =                  RETURN;
     (*KeywordMap)["void"] =                    VOID;
     (*KeywordMap)["bool"] =                    BOOL;
@@ -936,6 +937,11 @@ int TScanContext::tokenizeIdentifier()
     case CASE:
         return keyword;
 
+    case TERMINATE_INVOCATION:
+        if (!parseContext.extensionTurnedOn(E_GL_EXT_terminate_invocation))
+            return identifierOrType();
+        return keyword;
+
     case BUFFER:
         afterBuffer = true;
         if ((parseContext.isEsProfile() && parseContext.version < 310) ||

glslang/MachineIndependent/Versions.cpp

@@ -329,6 +329,7 @@ void TParseVersions::initializeExtensionBehavior()
     extensionBehavior[E_GL_EXT_shader_implicit_conversions] = EBhDisable;
     extensionBehavior[E_GL_EXT_fragment_shading_rate]       = EBhDisable;
     extensionBehavior[E_GL_EXT_shader_image_int64]   = EBhDisable;
+    extensionBehavior[E_GL_EXT_terminate_invocation]        = EBhDisable;
 
     // OVR extensions
     extensionBehavior[E_GL_OVR_multiview]                = EBhDisable;
@@ -411,7 +412,7 @@ void TParseVersions::getPreamble(std::string& preamble)
                 preamble += "#define GL_NV_shader_noperspective_interpolation 1\n";
             }
 
-    } else {
+    } else { // !isEsProfile()
         preamble =
             "#define GL_FRAGMENT_PRECISION_HIGH 1\n"
             "#define GL_ARB_texture_rectangle 1\n"
@@ -563,6 +564,11 @@ void TParseVersions::getPreamble(std::string& preamble)
             "#define GL_GOOGLE_include_directive 1\n"
             "#define GL_KHR_blend_equation_advanced 1\n"
             ;
+
+    // other general extensions
+    preamble +=
+            "#define GL_EXT_terminate_invocation 1\n"
+            ;
 #endif
 
     // #define VULKAN XXXX

glslang/MachineIndependent/Versions.h

@@ -299,6 +299,7 @@ const char* const E_GL_EXT_shader_subgroup_extended_types_int8    = "GL_EXT_shad
 const char* const E_GL_EXT_shader_subgroup_extended_types_int16   = "GL_EXT_shader_subgroup_extended_types_int16";
 const char* const E_GL_EXT_shader_subgroup_extended_types_int64   = "GL_EXT_shader_subgroup_extended_types_int64";
 const char* const E_GL_EXT_shader_subgroup_extended_types_float16 = "GL_EXT_shader_subgroup_extended_types_float16";
+const char* const E_GL_EXT_terminate_invocation = "GL_EXT_terminate_invocation";
 
 const char* const E_GL_EXT_shader_atomic_float = "GL_EXT_shader_atomic_float";
 

glslang/MachineIndependent/glslang.m4

@@ -293,6 +293,7 @@ GLSLANG_WEB_EXCLUDE_OFF
 %token <lex> CENTROID IN OUT INOUT
 %token <lex> STRUCT VOID WHILE
 %token <lex> BREAK CONTINUE DO ELSE FOR IF DISCARD RETURN SWITCH CASE DEFAULT
+%token <lex> TERMINATE_INVOCATION
 %token <lex> UNIFORM SHARED BUFFER
 %token <lex> FLAT SMOOTH LAYOUT
 
@@ -3927,6 +3928,10 @@ jump_statement
         parseContext.requireStage($1.loc, EShLangFragment, "discard");
         $$ = parseContext.intermediate.addBranch(EOpKill, $1.loc);
     }
+    | TERMINATE_INVOCATION SEMICOLON {
+        parseContext.requireStage($1.loc, EShLangFragment, "terminateInvocation");
+        $$ = parseContext.intermediate.addBranch(EOpTerminateInvocation, $1.loc);
+    }
     ;
 
 // Grammar Note:  No 'goto'.  Gotos are not supported.

glslang/MachineIndependent/glslang.y

@@ -293,6 +293,7 @@ extern int yylex(YYSTYPE*, TParseContext&);
 %token <lex> CENTROID IN OUT INOUT
 %token <lex> STRUCT VOID WHILE
 %token <lex> BREAK CONTINUE DO ELSE FOR IF DISCARD RETURN SWITCH CASE DEFAULT
+%token <lex> TERMINATE_INVOCATION
 %token <lex> UNIFORM SHARED BUFFER
 %token <lex> FLAT SMOOTH LAYOUT
 
@@ -3927,6 +3928,10 @@ jump_statement
         parseContext.requireStage($1.loc, EShLangFragment, "discard");
         $$ = parseContext.intermediate.addBranch(EOpKill, $1.loc);
     }
+    | TERMINATE_INVOCATION SEMICOLON {
+        parseContext.requireStage($1.loc, EShLangFragment, "terminateInvocation");
+        $$ = parseContext.intermediate.addBranch(EOpTerminateInvocation, $1.loc);
+    }
     ;
 
 // Grammar Note:  No 'goto'.  Gotos are not supported.

glslang/MachineIndependent/intermOut.cpp

@@ -1409,14 +1409,15 @@ bool TOutputTraverser::visitBranch(TVisit /* visit*/, TIntermBranch* node)
     OutputTreeText(out, node, depth);
 
     switch (node->getFlowOp()) {
-    case EOpKill:      out.debug << "Branch: Kill";           break;
-    case EOpBreak:     out.debug << "Branch: Break";          break;
-    case EOpContinue:  out.debug << "Branch: Continue";       break;
-    case EOpReturn:    out.debug << "Branch: Return";         break;
-    case EOpCase:      out.debug << "case: ";                 break;
-    case EOpDemote:    out.debug << "Demote";                 break;
-    case EOpDefault:   out.debug << "default: ";              break;
-    default:               out.debug << "Branch: Unknown Branch"; break;
+    case EOpKill:                out.debug << "Branch: Kill";                break;
+    case EOpTerminateInvocation: out.debug << "Branch: TerminateInvocation"; break;
+    case EOpBreak:               out.debug << "Branch: Break";               break;
+    case EOpContinue:            out.debug << "Branch: Continue";            break;
+    case EOpReturn:              out.debug << "Branch: Return";              break;
+    case EOpCase:                out.debug << "case: ";                      break;
+    case EOpDemote:              out.debug << "Demote";                      break;
+    case EOpDefault:             out.debug << "default: ";                   break;
+    default:                     out.debug << "Branch: Unknown Branch";      break;
     }
 
     if (node->getExpression()) {

gtests/AST.FromFile.cpp

@@ -278,6 +278,8 @@ INSTANTIATE_TEST_SUITE_P(
         "glsl.es320.subgroupShuffleRelative.comp",
         "glsl.es320.subgroupQuad.comp",
         "glsl.es320.subgroupVote.comp",
+        "terminate.frag",
+        "terminate.vert",
     })),
     FileNameAsCustomTestSuffix
 );

gtests/Spv.FromFile.cpp

@@ -436,6 +436,7 @@ INSTANTIATE_TEST_SUITE_P(
         "spv.specConstant.int16.comp",
         "spv.specConstant.int8.comp",
         "spv.storageBuffer.vert",
+        "spv.terminate.frag",
         "spv.precise.tese",
         "spv.precise.tesc",
         "spv.volatileAtomic.comp",