glsl: Add ir_demote

To represent the new `demote` keyword when using
EXT_demote_to_helper_invocation extension.  Most of the changes are to
include it in the visitors.

Demote is not considered a control flow, so also include an empty
visit member function in ir_control_flow_visitor.

Only NIR actually supports `demote`, so assert the translations for
TGSI and Mesa's gl_program -- since the demote is not expected to
appear for those.

Reviewed-by: Kenneth Graunke <[email protected]>

1 files changed, 7 insertions, 0 deletions

diff --git a/src/mesa/program/ir_to_mesa.cpp b/src/mesa/program/ir_to_mesa.cpp
index 777fd168c7e..679b46ba7ee 100644
--- a/src/mesa/program/ir_to_mesa.cpp
+++ b/src/mesa/program/ir_to_mesa.cpp
@@ -252,6 +252,7 @@ public:
    virtual void visit(ir_call *);
    virtual void visit(ir_return *);
    virtual void visit(ir_discard *);
+   virtual void visit(ir_demote *);
    virtual void visit(ir_texture *);
    virtual void visit(ir_if *);
    virtual void visit(ir_emit_vertex *);
@@ -2202,6 +2203,12 @@ ir_to_mesa_visitor::visit(ir_discard *ir)
 }
 
 void
+ir_to_mesa_visitor::visit(ir_demote *ir)
+{
+   assert(!"demote statement unsupported");
+}
+
+void
 ir_to_mesa_visitor::visit(ir_if *ir)
 {
    ir_to_mesa_instruction *if_inst;