Generate SPV_EXT_replicated_composites when requested by pragma.

Implement GL_EXT_spec_constant_composites.

Test/spv.specConstantComposite2.vert

@@ -0,0 +1,98 @@
+#version 450
+
+// constant_id specified scalar spec constants
+layout(constant_id = 200) const int spec_int = 3;
+layout(constant_id = 201) const float spec_float = 3.14;
+layout(constant_id = 202) const
+    double spec_double = 3.1415926535897932384626433832795;
+layout(constant_id = 203) const bool spec_bool = true;
+
+// const float cast_spec_float = float(spec_float);
+
+// Flat struct
+struct flat_struct {
+    int i;
+    float f;
+    double d;
+    bool b;
+};
+
+// Nesting struct
+struct nesting_struct {
+    flat_struct nested;
+    vec4 v;
+    int i;
+};
+
+// Expect OpSpecConstantComposite
+// Flat struct initializer
+//const flat_struct spec_flat_struct_all_spec = {spec_int, spec_float,
+//                                               spec_double, spec_bool};
+//const flat_struct spec_flat_struct_partial_spec = {30, 30.14, spec_double,
+//                                                   spec_bool};
+
+// Nesting struct initializer
+//const nesting_struct nesting_struct_ctor = {
+//    {spec_int, spec_float, spec_double, false},
+//    vec4(0.1, 0.1, 0.1, 0.1),
+//    spec_int};
+
+// Vector constructor
+//const vec4 spec_vec4_all_spec =
+//    vec4(spec_float, spec_float, spec_float, spec_float);
+//const vec4 spec_vec4_partial_spec =
+//    vec4(spec_float, spec_float, 300.14, 300.14);
+//const vec4 spec_vec4_from_one_scalar = vec4(spec_float);
+
+// Matrix constructor
+//const mat2x3 spec_mat2x3 = mat2x3(spec_float, spec_float, spec_float, 1.1, 2.2, 3.3);
+//const mat2x3 spec_mat2x3_from_one_scalar = mat2x3(spec_float);
+
+// Struct nesting constructor
+//const nesting_struct spec_nesting_struct_all_spec = {
+//    spec_flat_struct_all_spec, spec_vec4_all_spec, spec_int};
+//const nesting_struct spec_nesting_struct_partial_spec = {
+//    spec_flat_struct_partial_spec, spec_vec4_partial_spec, 3000};
+
+//const float spec_float_array[5] = {spec_float, spec_float, 1.0, 2.0, 3.0};
+//const int spec_int_array[5] = {spec_int, spec_int, 1, 2, 30};
+
+// global_vec4_array_with_spec_length is not a spec constant, but its array
+// size is. When calling global_vec4_array_with_spec_length.length(), A
+// TIntermSymbol Node should be returned, instead of a TIntermConstantUnion
+// node which represents a known constant value.
+in vec4 global_vec4_array_with_spec_length[spec_int];
+
+out vec4 color;
+
+void refer_primary_spec_const() {
+    if (spec_bool) color *= spec_int;
+}
+
+void refer_composite_spec_const() {
+    //color += spec_vec4_all_spec;
+    //color -= spec_vec4_partial_spec;
+}
+
+void refer_copmosite_dot_dereference() {
+    //color *= spec_nesting_struct_all_spec.i;
+    //color += spec_vec4_all_spec.x;
+}
+
+void refer_composite_bracket_dereference() {
+    //color -= spec_float_array[1];
+    //color /= spec_int_array[spec_int_array[spec_int]];
+}
+
+int refer_spec_const_array_length() {
+    int len = global_vec4_array_with_spec_length.length();
+    return len;
+}
+
+void declare_spec_const_in_func() {
+    //const nesting_struct spec_const_declared_in_func = {
+    //    spec_flat_struct_partial_spec, spec_vec4_partial_spec, 10};
+    //color /= spec_const_declared_in_func.i;
+}
+
+void main() {}