From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 16 Mar 2021 21:51:21 +0000 (+0200)
Subject: Add push_back_nocopy to NodeContainer for clarity
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=d4b8a3f67c1f7184124bf95caee7e36ae8d6c82a

Add push_back_nocopy to NodeContainer for clarity

It's not immediately obvious that pushing null and then assigning avoids
cloning the node.
---

diff --git a/source/glsl/generate.cpp b/source/glsl/generate.cpp
index 42b24a9c..56360991 100644
--- a/source/glsl/generate.cpp
+++ b/source/glsl/generate.cpp
@@ -579,8 +579,7 @@ void ExpressionResolver::convert_to(RefPtr<Expression> &expr, BasicTypeDeclarati
 	RefPtr<FunctionCall> call = new FunctionCall;
 	call->name = type.name;
 	call->constructor = true;
-	call->arguments.push_back(0);
-	call->arguments.back() = expr;
+	call->arguments.push_back_nocopy(expr);
 	call->type = &type;
 	expr = call;
 }
diff --git a/source/glsl/optimize.cpp b/source/glsl/optimize.cpp
index d5700255..b7a722f4 100644
--- a/source/glsl/optimize.cpp
+++ b/source/glsl/optimize.cpp
@@ -102,8 +102,7 @@ const string &InlineContentInjector::apply(Stage &stage, FunctionDeclaration &ta
 		SetForScope<Pass> set_pass(pass, RENAME);
 		var->visit(*this);
 
-		staging_block.body.push_back(0);
-		staging_block.body.back() = var;
+		staging_block.body.push_back_nocopy(var);
 		params.push_back(var);
 	}
 
@@ -117,8 +116,7 @@ const string &InlineContentInjector::apply(Stage &stage, FunctionDeclaration &ta
 		SetForScope<Pass> set_pass(pass, RENAME);
 		r_inlined_statement->visit(*this);
 
-		staging_block.body.push_back(0);
-		staging_block.body.back() = r_inlined_statement;
+		staging_block.body.push_back_nocopy(r_inlined_statement);
 	}
 
 	/* Now collect names from the staging block.  Local variables that would
diff --git a/source/glsl/syntax.h b/source/glsl/syntax.h
index 61294211..9bc3c5a8 100644
--- a/source/glsl/syntax.h
+++ b/source/glsl/syntax.h
@@ -96,6 +96,9 @@ class NodeContainer: public C
 public:
 	NodeContainer() { }
 	NodeContainer(const NodeContainer &);
+
+	void push_back_nocopy(const typename C::value_type &v)
+	{ C::push_back(0); C::back() = v; }
 };
 
 template<typename T>