SPV: Add auto location mapping of non-opaque non-block uniform variables.

Fix #1019.

Test/baseResults/glspv.frag.out

@@ -1,10 +1,9 @@
 glspv.frag
 ERROR: 0:4: '#error' : GL_SPIRV is set ( correct , not an error )  
 ERROR: 0:6: '#error' : GL_SPIR is 100  
-ERROR: 0:14: 'f' : non-opaque uniform variables need a layout(location=L) 
 ERROR: 0:19: 'input_attachment_index' : only allowed when using GLSL for Vulkan 
 ERROR: 0:19: '' :  syntax error, unexpected IDENTIFIER, expecting LEFT_BRACE or COMMA or SEMICOLON
-ERROR: 5 compilation errors.  No code generated.
+ERROR: 4 compilation errors.  No code generated.
 
 
 SPIR-V is not generated for failed compile or link

Test/baseResults/spv.looseUniformNoLoc.vert.out

@@ -0,0 +1,8 @@
+spv.looseUniformNoLoc.vert
+ERROR: spv.looseUniformNoLoc.vert:9: 'uv' : non-opaque uniform variables need a layout(location=L) 
+ERROR: 1 compilation errors.  No code generated.
+
+
+ERROR: Linking vertex stage: Missing entry point: Each stage requires one entry point
+
+SPIR-V is not generated for failed compile or link

Test/baseResults/spv.noBuiltInLoc.vert.out

@@ -1,12 +1,12 @@
 spv.noBuiltInLoc.vert
 // Module Version 10000
 // Generated by (magic number): 80001
-// Id's are bound by 23
+// Id's are bound by 33
 
                               Capability Shader
                1:             ExtInstImport  "GLSL.std.450"
                               MemoryModel Logical GLSL450
-                              EntryPoint Vertex 4  "main" 9 11 18
+                              EntryPoint Vertex 4  "main" 9 11 18 31 32
                               Source GLSL 450
                               Name 4  "main"
                               Name 9  "bar"
@@ -17,6 +17,11 @@ spv.noBuiltInLoc.vert
                               MemberName 16(gl_PerVertex) 2  "gl_ClipDistance"
                               MemberName 16(gl_PerVertex) 3  "gl_CullDistance"
                               Name 18  ""
+                              Name 24  "uv1"
+                              Name 26  "uv2"
+                              Name 29  "uv3"
+                              Name 31  "gl_VertexID"
+                              Name 32  "gl_InstanceID"
                               Decorate 9(bar) Location 0
                               Decorate 11(foo) Location 0
                               MemberDecorate 16(gl_PerVertex) 0 BuiltIn Position
@@ -24,6 +29,14 @@ spv.noBuiltInLoc.vert
                               MemberDecorate 16(gl_PerVertex) 2 BuiltIn ClipDistance
                               MemberDecorate 16(gl_PerVertex) 3 BuiltIn CullDistance
                               Decorate 16(gl_PerVertex) Block
+                              Decorate 24(uv1) Location 0
+                              Decorate 24(uv1) DescriptorSet 0
+                              Decorate 26(uv2) Location 1
+                              Decorate 26(uv2) DescriptorSet 0
+                              Decorate 29(uv3) Location 2
+                              Decorate 29(uv3) DescriptorSet 0
+                              Decorate 31(gl_VertexID) BuiltIn VertexId
+                              Decorate 32(gl_InstanceID) BuiltIn InstanceId
                2:             TypeVoid
                3:             TypeFunction 2
                6:             TypeFloat 32
@@ -40,6 +53,16 @@ spv.noBuiltInLoc.vert
               18:     17(ptr) Variable Output
               19:             TypeInt 32 1
               20:     19(int) Constant 0
+              23:             TypePointer UniformConstant 7(fvec4)
+         24(uv1):     23(ptr) Variable UniformConstant
+              25:             TypePointer UniformConstant 6(float)
+         26(uv2):     25(ptr) Variable UniformConstant
+              27:             TypeVector 6(float) 3
+              28:             TypePointer UniformConstant 27(fvec3)
+         29(uv3):     28(ptr) Variable UniformConstant
+              30:             TypePointer Input 19(int)
+ 31(gl_VertexID):     30(ptr) Variable Input
+32(gl_InstanceID):     30(ptr) Variable Input
          4(main):           2 Function None 3
                5:             Label
               12:    7(fvec4) Load 11(foo)

Test/runtests

@@ -109,8 +109,10 @@ diff -b $BASEDIR/hlsl.explicitDescriptorSet-2.frag.out $TARGETDIR/hlsl.explicitD
 echo Testing SPV no location
 $EXE -V -C spv.noLocation.vert > $TARGETDIR/spv.noLocation.vert.out
 diff -b $BASEDIR/spv.noLocation.vert.out $TARGETDIR/spv.noLocation.vert.out || HASERROR=1
-$EXE -H --aml spv.noBuiltInLoc.vert > $TARGETDIR/spv.noBuiltInLoc.vert.out
+$EXE -G -H --aml spv.noBuiltInLoc.vert > $TARGETDIR/spv.noBuiltInLoc.vert.out
 diff -b $BASEDIR/spv.noBuiltInLoc.vert.out $TARGETDIR/spv.noBuiltInLoc.vert.out || HASERROR=1
+$EXE -G spv.looseUniformNoLoc.vert > $TARGETDIR/spv.looseUniformNoLoc.vert.out
+diff -b $BASEDIR/spv.looseUniformNoLoc.vert.out $TARGETDIR/spv.looseUniformNoLoc.vert.out || HASERROR=1
 
 #
 # Testing debug information

Test/spv.looseUniformNoLoc.vert

@@ -0,0 +1,15 @@
+#version 450 core
+
+layout(location = 0)
+in  vec4 foo;
+
+layout(location = 0)
+out vec4 bar;
+
+uniform vec4 uv;
+
+void main()
+{
+    bar = foo;
+    gl_Position = foo;
+}

Test/spv.noBuiltInLoc.vert

@@ -6,6 +6,10 @@ in  vec4 foo;
 layout(location = 0)
 out vec4 bar;
 
+uniform vec4 uv1;
+uniform float uv2;
+uniform vec3 uv3;
+
 void main()
 {
     bar = foo;

glslang/MachineIndependent/ParseHelper.cpp

@@ -2493,8 +2493,8 @@ void TParseContext::transparentOpaqueCheck(const TSourceLoc& loc, const TType& t
         // Vulkan doesn't allow transparent uniforms outside of blocks
         if (spvVersion.vulkan > 0)
             vulkanRemoved(loc, "non-opaque uniforms outside a block");
-        // OpenGL wants locations on these
+        // OpenGL wants locations on these (unless they are getting automapped)
-        if (spvVersion.openGl > 0 && !type.getQualifier().hasLocation())
+        if (spvVersion.openGl > 0 && !type.getQualifier().hasLocation() && !intermediate.getAutoMapLocations())
             error(loc, "non-opaque uniform variables need a layout(location=L)", identifier.c_str(), "");
     }
 }

glslang/MachineIndependent/iomapper.cpp

@@ -253,10 +253,14 @@ struct TResolverUniformAdaptor
         ent.newBinding = -1;
         ent.newSet = -1;
         ent.newIndex = -1;
-        const bool isValid = resolver.validateBinding(stage, ent.symbol->getName().c_str(), ent.symbol->getType(), ent.live);
+        const bool isValid = resolver.validateBinding(stage, ent.symbol->getName().c_str(), ent.symbol->getType(),
+                                                             ent.live);
         if (isValid) {
-            ent.newBinding = resolver.resolveBinding(stage, ent.symbol->getName().c_str(), ent.symbol->getType(), ent.live);
+            ent.newBinding = resolver.resolveBinding(stage, ent.symbol->getName().c_str(), ent.symbol->getType(),
+                                                            ent.live);
             ent.newSet = resolver.resolveSet(stage, ent.symbol->getName().c_str(), ent.symbol->getType(), ent.live);
+            ent.newLocation = resolver.resolveUniformLocation(stage, ent.symbol->getName().c_str(),
+                                                                     ent.symbol->getType(), ent.live);
 
             if (ent.newBinding != -1) {
                 if (ent.newBinding >= int(TQualifier::layoutBindingEnd)) {
@@ -356,6 +360,7 @@ struct TDefaultIoResolverBase : public glslang::TIoMapResolver
     std::vector<std::string> baseResourceSetBinding;
     bool doAutoBindingMapping;
     bool doAutoLocationMapping;
+    int nextUniformLocation;
     typedef std::vector<int> TSlotSet;
     typedef std::unordered_map<int, TSlotSet> TSlotSetMap;
     TSlotSetMap slots;
@@ -411,7 +416,27 @@ struct TDefaultIoResolverBase : public glslang::TIoMapResolver
 
         return 0;
     }
+    int resolveUniformLocation(EShLanguage /*stage*/, const char* /*name*/, const glslang::TType& type, bool is_live) override
+    {
+        // kick out of not doing this
+        if (!doAutoLocationMapping)
+            return -1;
 
+        // no locations added if already present, a built-in variable, a block, or an opaque
+        if (type.getQualifier().hasLocation() || type.isBuiltIn() ||
+            type.getBasicType() == EbtBlock || type.containsOpaque())
+            return -1;
+
+        // no locations on blocks of built-in variables
+        if (type.isStruct()) {
+            if (type.getStruct()->size() < 1)
+                return -1;
+            if ((*type.getStruct())[0].type->isBuiltIn())
+                return -1;
+        }
+
+        return nextUniformLocation++;
+    }
     bool validateInOut(EShLanguage /*stage*/, const char* /*name*/, const TType& /*type*/, bool /*is_live*/) override
     {
         return true;
@@ -700,6 +725,7 @@ bool TIoMapper::addStage(EShLanguage stage, TIntermediate &intermediate, TInfoSi
         resolverBase->baseResourceSetBinding = intermediate.getResourceSetBinding();
         resolverBase->doAutoBindingMapping = intermediate.getAutoMapBindings();
         resolverBase->doAutoLocationMapping = intermediate.getAutoMapLocations();
+        resolverBase->nextUniformLocation = 0;
 
         resolver = resolverBase;
     }

glslang/Public/ShaderLang.h

@@ -533,9 +533,10 @@ class TIoMapper;
 
 // Allows to customize the binding layout after linking.
 // All used uniform variables will invoke at least validateBinding.
-// If validateBinding returned true then the other resolveBinding
+// If validateBinding returned true then the other resolveBinding,
-// and resolveSet are invoked to resolve the binding and descriptor
+// resolveSet, and resolveLocation are invoked to resolve the binding
-// set index respectively.
+// and descriptor set index respectively.
+//
 // Invocations happen in a particular order:
 // 1) all shader inputs
 // 2) all shader outputs
@@ -567,6 +568,9 @@ public:
   // Should return a value >= 0 if the current set should be overridden.
   // Return -1 if the current set (including no set) should be kept.
   virtual int resolveSet(EShLanguage stage, const char* name, const TType& type, bool is_live) = 0;
+  // Should return a value >= 0 if the current location should be overridden.
+  // Return -1 if the current location (including no location) should be kept.
+  virtual int resolveUniformLocation(EShLanguage stage, const char* name, const TType& type, bool is_live) = 0;
   // Should return true if the resulting/current setup would be okay.
   // Basic idea is to do aliasing checks and reject invalid semantic names.
   virtual bool validateInOut(EShLanguage stage, const char* name, const TType& type, bool is_live) = 0;