Implement GL_EXT_maximal_reconvergence

SPIRV/GLSL.ext.KHR.h

@@ -56,5 +56,6 @@ static const char* const E_SPV_KHR_fragment_shader_barycentric = "SPV_KHR_fragme
 static const char* const E_SPV_AMD_shader_early_and_late_fragment_tests = "SPV_AMD_shader_early_and_late_fragment_tests";
 static const char* const E_SPV_KHR_ray_tracing_position_fetch   = "SPV_KHR_ray_tracing_position_fetch";
 static const char* const E_SPV_KHR_cooperative_matrix           = "SPV_KHR_cooperative_matrix";
+static const char* const E_SPV_KHR_maximal_reconvergence        = "SPV_KHR_maximal_reconvergence";
 
 #endif  // #ifndef GLSLextKHR_H

SPIRV/GlslangToSpv.cpp

@@ -1635,6 +1635,10 @@ TGlslangToSpvTraverser::TGlslangToSpvTraverser(unsigned int spvVersion,
         builder.addExtension(spv::E_SPV_KHR_subgroup_uniform_control_flow);
         builder.addExecutionMode(shaderEntry, spv::ExecutionModeSubgroupUniformControlFlowKHR);
     }
+    if (glslangIntermediate->getMaximalReconvergence()) {
+        builder.addExtension(spv::E_SPV_KHR_maximal_reconvergence);
+        builder.addExecutionMode(shaderEntry, spv::ExecutionModeMaximallyReconvergesKHR);
+    }
 
     unsigned int mode;
     switch (glslangIntermediate->getStage()) {

SPIRV/doc.cpp

@@ -198,6 +198,7 @@ const char* ExecutionModeString(int mode)
     case ExecutionModeStencilRefGreaterBackAMD:      return "StencilRefGreaterBackAMD";
     case ExecutionModeStencilRefReplacingEXT:        return "StencilRefReplacingEXT";
     case ExecutionModeSubgroupUniformControlFlowKHR: return "SubgroupUniformControlFlow";
+    case ExecutionModeMaximallyReconvergesKHR:       return "MaximallyReconverges";
 
     case ExecutionModeOutputLinesNV:                 return "OutputLinesNV";
     case ExecutionModeOutputPrimitivesNV:            return "OutputPrimitivesNV";

SPIRV/spirv.hpp

@@ -198,6 +198,7 @@ enum ExecutionMode {
     ExecutionModeNoGlobalOffsetINTEL = 5895,
     ExecutionModeNumSIMDWorkitemsINTEL = 5896,
     ExecutionModeSchedulerTargetFmaxMhzINTEL = 5903,
+    ExecutionModeMaximallyReconvergesKHR = 6023,
     ExecutionModeStreamingInterfaceINTEL = 6154,
     ExecutionModeNamedBarrierCountINTEL = 6417,
     ExecutionModeMax = 0x7fffffff,

Test/baseResults/spv.maximalReconvergence.vert.out

@@ -0,0 +1,22 @@
+spv.maximalReconvergence.vert
+WARNING: 0:5: '' : attribute with arguments not recognized, skipping 
+
+// Module Version 10000
+// Generated by (magic number): 8000b
+// Id's are bound by 6
+
+                              Capability Shader
+                              Extension  "SPV_KHR_maximal_reconvergence"
+               1:             ExtInstImport  "GLSL.std.450"
+                              MemoryModel Logical GLSL450
+                              EntryPoint Vertex 4  "main"
+                              ExecutionMode 4 MaximallyReconverges
+                              Source GLSL 460
+                              SourceExtension  "GL_EXT_maximal_reconvergence"
+                              Name 4  "main"
+               2:             TypeVoid
+               3:             TypeFunction 2
+         4(main):           2 Function None 3
+               5:             Label
+                              Return
+                              FunctionEnd

Test/spv.maximalReconvergence.vert

@@ -0,0 +1,7 @@
+#version 460
+
+#extension GL_EXT_maximal_reconvergence : enable
+
+[[random(4)]] void main() [[maximal_reconvergence]]
+{
+}

glslang/MachineIndependent/Versions.cpp

@@ -258,6 +258,7 @@ void TParseVersions::initializeExtensionBehavior()
     extensionBehavior[E_GL_EXT_shader_16bit_storage]                    = EBhDisable;
     extensionBehavior[E_GL_EXT_shader_8bit_storage]                     = EBhDisable;
     extensionBehavior[E_GL_EXT_subgroup_uniform_control_flow]           = EBhDisable;
+    extensionBehavior[E_GL_EXT_maximal_reconvergence]                   = EBhDisable;
 
     extensionBehavior[E_GL_EXT_fragment_shader_barycentric]             = EBhDisable;
 
@@ -446,6 +447,7 @@ void TParseVersions::getPreamble(std::string& preamble)
             if (version >= 310) {
                 preamble += "#define GL_EXT_null_initializer 1\n";
                 preamble += "#define GL_EXT_subgroup_uniform_control_flow 1\n";
+                preamble += "#define GL_EXT_maximal_reconvergence 1\n";
             }
 
     } else { // !isEsProfile()
@@ -599,6 +601,7 @@ void TParseVersions::getPreamble(std::string& preamble)
         if (version >= 140) {
             preamble += "#define GL_EXT_null_initializer 1\n";
             preamble += "#define GL_EXT_subgroup_uniform_control_flow 1\n";
+            preamble += "#define GL_EXT_maximal_reconvergence 1\n";
         }
         if (version >= 130) {
             preamble +="#define GL_FRAGMENT_PRECISION_HIGH 1\n";

glslang/MachineIndependent/Versions.h

@@ -217,6 +217,7 @@ const char* const E_GL_EXT_mesh_shader                      = "GL_EXT_mesh_shade
 const char* const E_GL_EXT_opacity_micromap                 = "GL_EXT_opacity_micromap";
 const char* const E_GL_EXT_draw_instanced                   = "GL_EXT_draw_instanced";
 const char* const E_GL_EXT_texture_array                    = "GL_EXT_texture_array";
+const char* const E_GL_EXT_maximal_reconvergence            = "GL_EXT_maximal_reconvergence";
 
 // Arrays of extensions for the above viewportEXTs duplications
 

glslang/MachineIndependent/attribute.cpp

@@ -125,6 +125,8 @@ TAttributeType TParseContext::attributeFromName(const TString& name) const
         return EatSubgroupUniformControlFlow;
     else if (name == "export")
         return EatExport;
+    else if (name == "maximal_reconvergence")
+        return EatMaximalReconvergence;
     else
         return EatNone;
 }
@@ -360,6 +362,10 @@ void TParseContext::handleFunctionAttributes(const TSourceLoc& loc, const TAttri
             requireExtensions(loc, 1, &E_GL_EXT_subgroup_uniform_control_flow, "attribute");
             intermediate.setSubgroupUniformControlFlow();
             break;
+        case EatMaximalReconvergence:
+            requireExtensions(loc, 1, &E_GL_EXT_maximal_reconvergence, "attribute");
+            intermediate.setMaximalReconvergence();
+            break;
         default:
             warn(loc, "attribute does not apply to a function", "", "");
             break;

glslang/MachineIndependent/attribute.h

@@ -121,6 +121,7 @@ namespace glslang {
         EatNonReadable,
         EatSubgroupUniformControlFlow,
         EatExport,
+        EatMaximalReconvergence,
     };
 
     class TIntermAggregate;

glslang/MachineIndependent/glslang.y

@@ -964,18 +964,24 @@ function_prototype
         $$.function = $1;
         if (parseContext.compileOnly) $$.function->setExport();
         $$.loc = $2.loc;
+        const char * extensions[2] = { E_GL_EXT_subgroup_uniform_control_flow, E_GL_EXT_maximal_reconvergence };
+        parseContext.requireExtensions($2.loc, 2, extensions, "attribute");
         parseContext.handleFunctionAttributes($2.loc, *$3);
     }
     | attribute function_declarator RIGHT_PAREN {
         $$.function = $2;
         if (parseContext.compileOnly) $$.function->setExport();
         $$.loc = $3.loc;
+        const char * extensions[2] = { E_GL_EXT_subgroup_uniform_control_flow, E_GL_EXT_maximal_reconvergence };
+        parseContext.requireExtensions($3.loc, 2, extensions, "attribute");
         parseContext.handleFunctionAttributes($3.loc, *$1);
     }
     | attribute function_declarator RIGHT_PAREN attribute {
         $$.function = $2;
         if (parseContext.compileOnly) $$.function->setExport();
         $$.loc = $3.loc;
+        const char * extensions[2] = { E_GL_EXT_subgroup_uniform_control_flow, E_GL_EXT_maximal_reconvergence };
+        parseContext.requireExtensions($3.loc, 2, extensions, "attribute");
         parseContext.handleFunctionAttributes($3.loc, *$1);
         parseContext.handleFunctionAttributes($3.loc, *$4);
     }

glslang/MachineIndependent/intermOut.cpp

@@ -1512,6 +1512,9 @@ void TIntermediate::output(TInfoSink& infoSink, bool tree)
     if (getSubgroupUniformControlFlow())
         infoSink.debug << "subgroup_uniform_control_flow\n";
 
+    if (getMaximalReconvergence())
+        infoSink.debug << "maximal_reconvergence\n";
+
     switch (language) {
     case EShLangVertex:
         break;

glslang/MachineIndependent/localintermediate.h

@@ -345,6 +345,7 @@ public:
         needToLegalize(false),
         binaryDoubleOutput(false),
         subgroupUniformControlFlow(false),
+        maximalReconvergence(false),
         usePhysicalStorageBuffer(false),
         spirvRequirement(nullptr),
         spirvExecutionMode(nullptr),
@@ -963,6 +964,9 @@ public:
     void setSubgroupUniformControlFlow() { subgroupUniformControlFlow = true; }
     bool getSubgroupUniformControlFlow() const { return subgroupUniformControlFlow; }
 
+    void setMaximalReconvergence() { maximalReconvergence = true; }
+    bool getMaximalReconvergence() const { return maximalReconvergence; }
+
     // GL_EXT_spirv_intrinsics
     void insertSpirvRequirement(const TSpirvRequirement* spirvReq);
     bool hasSpirvRequirement() const { return spirvRequirement != nullptr; }
@@ -1226,6 +1230,7 @@ protected:
     bool needToLegalize;
     bool binaryDoubleOutput;
     bool subgroupUniformControlFlow;
+    bool maximalReconvergence;
     bool usePhysicalStorageBuffer;
 
     TSpirvRequirement* spirvRequirement;

gtests/Spv.FromFile.cpp

@@ -436,6 +436,7 @@ INSTANTIATE_TEST_SUITE_P(
         "spv.matFun.vert",
         "spv.matrix.frag",
         "spv.matrix2.frag",
+        "spv.maximalReconvergence.vert",
         "spv.memoryQualifier.frag",
         "spv.merge-unreachable.frag",
         "spv.multiStruct.comp",

known_good.json

@@ -5,14 +5,14 @@
       "site" : "github",
       "subrepo" : "KhronosGroup/SPIRV-Tools",
       "subdir" : "External/spirv-tools",
-      "commit": "f0cc85efdbbe3a46eae90e0f915dc1509836d0fc"
+      "commit": "de3d5acc04fd203e3e5120a00f168465ecb2e4e4"
     },
     {
       "name" : "spirv-tools/external/spirv-headers",
       "site" : "github",
       "subrepo" : "KhronosGroup/SPIRV-Headers",
       "subdir" : "External/spirv-tools/external/spirv-headers",
-      "commit" : "1c6bb2743599e6eb6f37b2969acc0aef812e32e3"
+      "commit" : "ae6a8b39717523d96683bc0d20b541944e28072f"
     },
     {
       "name": "googletest",