SPV: Allow push constant buffers to not have an instance name.

Test/baseResults/spv.pushConstantAnon.vert.out

+spv.pushConstantAnon.vert
+Warning, version 400 is not yet complete; most version-specific features are present, but some are missing.
+
+// Module Version 10000
+// Generated by (magic number): 80001
+// Id's are bound by 38
+
+                              Capability Shader
+               1:             ExtInstImport  "GLSL.std.450"
+                              MemoryModel Logical GLSL450
+                              EntryPoint Vertex 4  "main" 24
+                              Source GLSL 400
+                              Name 4  "main"
+                              Name 11  "Material"
+                              MemberName 11(Material) 0  "kind"
+                              MemberName 11(Material) 1  "fa"
+                              Name 13  ""
+                              Name 24  "color"
+                              Decorate 10 ArrayStride 4
+                              MemberDecorate 11(Material) 0 Offset 0
+                              MemberDecorate 11(Material) 1 Offset 4
+                              Decorate 11(Material) Block
+               2:             TypeVoid
+               3:             TypeFunction 2
+               6:             TypeInt 32 1
+               7:             TypeFloat 32
+               8:             TypeInt 32 0
+               9:      8(int) Constant 3
+              10:             TypeArray 7(float) 9
+    11(Material):             TypeStruct 6(int) 10
+              12:             TypePointer PushConstant 11(Material)
+              13:     12(ptr) Variable PushConstant
+              14:      6(int) Constant 0
+              15:             TypePointer PushConstant 6(int)
+              22:             TypeVector 7(float) 4
+              23:             TypePointer Output 22(fvec4)
+       24(color):     23(ptr) Variable Output
+              25:    7(float) Constant 1045220557
+              26:   22(fvec4) ConstantComposite 25 25 25 25
+              28:    7(float) Constant 1056964608
+              29:   22(fvec4) ConstantComposite 28 28 28 28
+              31:      6(int) Constant 1
+              32:             TypePointer PushConstant 7(float)
+         4(main):           2 Function None 3
+               5:             Label
+              16:     15(ptr) AccessChain 13 14
+              17:      6(int) Load 16
+                              SelectionMerge 21 None
+                              Switch 17 20 
+                                     case 1: 18
+                                     case 2: 19
+              20:               Label
+              33:     32(ptr)   AccessChain 13 31 31
+              34:    7(float)   Load 33
+              35:   22(fvec4)   CompositeConstruct 34 34 34 34
+                                Store 24(color) 35
+                                Branch 21
+              18:               Label
+                                Store 24(color) 26
+                                Branch 21
+              19:               Label
+                                Store 24(color) 29
+                                Branch 21
+              21:             Label
+                              Return
+                              FunctionEnd

Test/baseResults/vulkan.frag.out

@@ -19,7 +19,6 @@ ERROR: 0:39: 'push_constant' : can only be used with a uniform
 ERROR: 0:43: 'non-opaque uniforms outside a block' : not allowed when using GLSL for Vulkan 
 ERROR: 0:43: 'push_constant' : can only be used with a block 
 ERROR: 0:45: 'push_constant' : cannot declare a default, can only be used on a block 
-ERROR: 0:47: 'push_constant' : requires an instance name 
 ERROR: 0:52: 'input_attachment_index' : can only be used with a subpass 
 ERROR: 0:53: 'input_attachment_index' : can only be used with a subpass 
 ERROR: 0:54: 'subpass' : requires an input_attachment_index layout qualifier 
@@ -41,7 +40,7 @@ ERROR: 0:93: ',' : sampler constructor must appear at point of use
 ERROR: 0:94: ':' :  wrong operand types: no operation ':' exists that takes a left-hand operand of type 'temp sampler2D' and a right operand of type 'temp sampler2D' (or there is no acceptable conversion)
 ERROR: 0:94: 'call argument' : sampler constructor must appear at point of use 
 ERROR: 0:96: 'gl_NumSamples' : undeclared identifier 
-ERROR: 39 compilation errors.  No code generated.
+ERROR: 38 compilation errors.  No code generated.
 
 
 ERROR: Linking fragment stage: Only one push_constant block is allowed per stage

Test/spv.pushConstantAnon.vert

+#version 400
+
+layout(push_constant) uniform Material {
+    int kind;
+    float fa[3];
+};
+
+out vec4 color;
+
+void main()
+{
+    switch (kind) {
+    case 1:  color = vec4(0.2); break;
+    case 2:  color = vec4(0.5); break;
+    default: color = vec4(fa[1]); break;
+    }
+}

Test/vulkan.frag

@@ -46,7 +46,7 @@ layout(push_constant) uniform;                // ERROR, needs an object
 
 layout(push_constant) uniform pcb2 {
     int a;
-};                                            // ERROR, no instance name
+};                                            // Okay now to have no instance name
 
 layout(input_attachment_index = 2) uniform subpassInput subD;
 layout(input_attachment_index = 3) uniform texture2D subDbad1;          // ERROR, not a texture

glslang/Include/revision.h

@@ -2,5 +2,5 @@
 // For the version, it uses the latest git tag followed by the number of commits.
 // For the date, it uses the current date (when then script is run).
 
-#define GLSLANG_REVISION "Overload400-PrecQual.1875"
-#define GLSLANG_DATE "03-Mar-2017"
+#define GLSLANG_REVISION "Overload400-PrecQual.1878"
+#define GLSLANG_DATE "06-Mar-2017"

glslang/MachineIndependent/ParseHelper.cpp

@@ -5797,11 +5797,8 @@ void TParseContext::blockQualifierCheck(const TSourceLoc& loc, const TQualifier&
         error(loc, "cannot use sample qualifier on an interface block", "sample", "");
     if (qualifier.invariant)
         error(loc, "cannot use invariant qualifier on an interface block", "invariant", "");
-    if (qualifier.layoutPushConstant) {
+    if (qualifier.layoutPushConstant)
         intermediate.addPushConstantCount();
-        if (! instanceName)
-            error(loc, "requires an instance name", "push_constant", "");
-    }
 }
 
 //

gtests/Spv.FromFile.cpp

@@ -295,6 +295,7 @@ INSTANTIATE_TEST_CASE_P(
         "spv.separate.frag",
         "spv.shortCircuit.frag",
         "spv.pushConstant.vert",
+        "spv.pushConstantAnon.vert",
         "spv.subpass.frag",
         "spv.specConstant.vert",
         "spv.specConstant.comp",