From: Mikko Rasa <tdb@tdb.fi>
Date: Mon, 12 Apr 2021 15:00:34 +0000 (+0300)
Subject: Don't ignore structs entirely in UnusedVariableRemover
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=72a02f2f3f1c454aa670b256262d7bc0541222e3

Don't ignore structs entirely in UnusedVariableRemover

Structs may have arrays in them, and array sizes may have references to
specialization constants which must be kept.
---

diff --git a/source/glsl/optimize.cpp b/source/glsl/optimize.cpp
index 68d3f1d7..bdaced5c 100644
--- a/source/glsl/optimize.cpp
+++ b/source/glsl/optimize.cpp
@@ -1010,6 +1010,7 @@ UnusedVariableRemover::UnusedVariableRemover():
 	r_assignment(0),
 	assignment_target(false),
 	r_side_effects(false),
+	in_struct(false),
 	composite_reference(false)
 { }
 
@@ -1233,8 +1234,19 @@ void UnusedVariableRemover::visit(ExpressionStatement &expr)
 		unused_nodes.insert(&expr);
 }
 
+void UnusedVariableRemover::visit(StructDeclaration &strct)
+{
+	SetFlag set_struct(in_struct);
+	TraversingVisitor::visit(strct);
+}
+
 void UnusedVariableRemover::visit(VariableDeclaration &var)
 {
+	TraversingVisitor::visit(var);
+
+	if(in_struct)
+		return;
+
 	VariableInfo &var_info = variables[&var];
 	var_info.interface_block = interface_block;
 
@@ -1250,7 +1262,6 @@ void UnusedVariableRemover::visit(VariableDeclaration &var)
 		var_info.initialized = true;
 		record_assignment(&var, *var.init_expression);
 	}
-	TraversingVisitor::visit(var);
 }
 
 void UnusedVariableRemover::visit(InterfaceBlock &iface)
diff --git a/source/glsl/optimize.h b/source/glsl/optimize.h
index e21dd98f..ea61b671 100644
--- a/source/glsl/optimize.h
+++ b/source/glsl/optimize.h
@@ -300,6 +300,7 @@ private:
 	Assignment *r_assignment;
 	bool assignment_target;
 	bool r_side_effects;
+	bool in_struct;
 	bool composite_reference;
 	Assignment::Target r_reference;
 	std::set<Node *> unused_nodes;
@@ -323,8 +324,7 @@ private:
 	virtual void visit(FunctionCall &);
 	void record_assignment(const Assignment::Target &, Node &);
 	virtual void visit(ExpressionStatement &);
-	// Ignore structs because their members can't be accessed directly.
-	virtual void visit(StructDeclaration &) { }
+	virtual void visit(StructDeclaration &);
 	virtual void visit(VariableDeclaration &);
 	virtual void visit(InterfaceBlock &);
 	void merge_variables(const BlockVariableMap &);
diff --git a/tests/glsl/specialized_array_in_struct.glsl b/tests/glsl/specialized_array_in_struct.glsl
new file mode 100644
index 00000000..4a6d9ab6
--- /dev/null
+++ b/tests/glsl/specialized_array_in_struct.glsl
@@ -0,0 +1,50 @@
+layout(constant_id=auto) const int max_colors = 2;
+struct ColorInfo
+{
+	vec4 color;
+};
+uniform Colors
+{
+	ColorInfo colors[max_colors];
+};
+
+#pragma MSP stage(vertex)
+layout(location=0) in vec4 position;
+void main()
+{
+	gl_Position = position;
+}
+
+#pragma MSP stage(fragment)
+layout(location=0) out vec4 frag_color;
+void main()
+{
+	frag_color = colors[0].color;
+}
+
+// Compile mode: module
+
+/* Expected output: vertex
+layout(location=0) in vec4 position;
+void main()
+{
+	gl_Position = position;
+}
+*/
+
+/* Expected output: fragment
+layout(constant_id=953017667) const int max_colors = 2;
+struct ColorInfo
+{
+	vec4 color;
+};
+layout(binding=23) uniform Colors
+{
+	ColorInfo colors[max_colors];
+};
+layout(location=0) out vec4 frag_color;
+void main()
+{
+	frag_color = colors[0].color;
+}
+*/