Add a utility function for following a chain of base types

[libs/gl.git] / source / glsl / syntax.cpp

diff --git a/source/glsl/syntax.cpp b/source/glsl/syntax.cpp
index 8b00e82e46eae73f397c599f6a9e3ea0008b4e3a..40f6d4f660b24c84dff02a910951c71c87ad6c4e 100644 (file)
--- a/source/glsl/syntax.cpp
+++ b/source/glsl/syntax.cpp
@@ -294,6 +294,7 @@ void VariableDeclaration::visit(NodeVisitor &visitor)
 
 InterfaceBlock::InterfaceBlock(const InterfaceBlock &other):
        Statement(other),
+       layout(other.layout),
        interface(other.interface),
        block_name(other.block_name),
        members(other.members),
@@ -401,6 +402,19 @@ string get_unused_variable_name(const Block &block, const string &base)
        }
 }
 
+const TypeDeclaration *get_ultimate_base_type(const TypeDeclaration *type)
+{
+       if(!type)
+               return 0;
+       while(const BasicTypeDeclaration *basic = dynamic_cast<const BasicTypeDeclaration *>(type))
+       {
+               if(!basic->base_type)
+                       break;
+               type = basic->base_type;
+       }
+       return type;
+}
+
 int get_layout_value(const Layout &layout, const string &name, int def_value)
 {
        auto i = find_member(layout.qualifiers, name, &Layout::Qualifier::name);
@@ -414,6 +428,32 @@ void add_to_chain(Assignment::Target &target, Assignment::Target::ChainType type
        ++target.chain_len;
 }
 
+bool targets_overlap(const Assignment::Target &target1, const Assignment::Target &target2)
+{
+       bool overlap = (target1.declaration==target2.declaration);
+       for(unsigned i=0; (overlap && i<target1.chain_len && i<target2.chain_len); ++i)
+       {
+               Assignment::Target::ChainType type1 = static_cast<Assignment::Target::ChainType>(target1.chain[i]&0xC0);
+               Assignment::Target::ChainType type2 = static_cast<Assignment::Target::ChainType>(target2.chain[i]&0xC0);
+               unsigned index1 = target1.chain[i]&0x3F;
+               unsigned index2 = target2.chain[i]&0x3F;
+               if(type1==Assignment::Target::SWIZZLE || type2==Assignment::Target::SWIZZLE)
+               {
+                       if(type1==Assignment::Target::SWIZZLE && type2==Assignment::Target::SWIZZLE)
+                               overlap = index1&index2;
+                       else if(type1==Assignment::Target::ARRAY && index1<4)
+                               overlap = index2&(1<<index1);
+                       else if(type2==Assignment::Target::ARRAY && index2<4)
+                               overlap = index1&(1<<index2);
+                       // Treat other combinations as overlapping (shouldn't happen)
+               }
+               else
+                       overlap = (type1==type2 && (index1==index2 || index1==0x3F || index2==0x3F));
+       }
+
+       return overlap;
+}
+
 } // namespace SL
 } // namespace GL
 } // namespace Msp