From 597d37b7315f5ffcb7d99b90710b0e583b3ebf34 Mon Sep 17 00:00:00 2001
From: chriseth <chris@ethereum.org>
Date: Thu, 25 Apr 2019 00:01:13 +0200
Subject: [PATCH] Implement for loops.

---
 .../codegen/ir/IRGeneratorForStatements.cpp   | 37 +++++++++++++++++++
 .../codegen/ir/IRGeneratorForStatements.h     |  3 ++
 2 files changed, 40 insertions(+)

diff --git a/libsolidity/codegen/ir/IRGeneratorForStatements.cpp b/libsolidity/codegen/ir/IRGeneratorForStatements.cpp
index 39fd826ab..1fad14494 100644
--- a/libsolidity/codegen/ir/IRGeneratorForStatements.cpp
+++ b/libsolidity/codegen/ir/IRGeneratorForStatements.cpp
@@ -22,6 +22,7 @@
 
 #include <libsolidity/codegen/ir/IRGenerationContext.h>
 #include <libsolidity/codegen/YulUtilFunctions.h>
+#include <libsolidity/ast/TypeProvider.h>
 
 #include <libyul/AsmPrinter.h>
 #include <libyul/AsmData.h>
@@ -126,6 +127,42 @@ bool IRGeneratorForStatements::visit(Assignment const& _assignment)
 	return false;
 }
 
+bool IRGeneratorForStatements::visit(ForStatement const& _for)
+{
+	m_code << "for {\n";
+	if (_for.initializationExpression())
+		_for.initializationExpression()->accept(*this);
+	m_code << "} return_flag {\n";
+	if (_for.loopExpression())
+		_for.loopExpression()->accept(*this);
+	m_code << "}\n";
+	if (_for.condition())
+	{
+		_for.condition()->accept(*this);
+		m_code <<
+			"if iszero(" <<
+			expressionAsType(*_for.condition(), *TypeProvider::boolean()) <<
+			") { break }\n";
+	}
+	_for.body().accept(*this);
+	m_code << "}\n";
+	// Bubble up the return condition.
+	m_code << "if iszero(return_flag) { break }\n";
+	return false;
+}
+
+bool IRGeneratorForStatements::visit(Continue const&)
+{
+	m_code << "continue\n";
+	return false;
+}
+
+bool IRGeneratorForStatements::visit(Break const&)
+{
+	m_code << "break\n";
+	return false;
+}
+
 bool IRGeneratorForStatements::visit(Return const& _return)
 {
 	if (Expression const* value = _return.expression())
diff --git a/libsolidity/codegen/ir/IRGeneratorForStatements.h b/libsolidity/codegen/ir/IRGeneratorForStatements.h
index b40d50ff4..331962f84 100644
--- a/libsolidity/codegen/ir/IRGeneratorForStatements.h
+++ b/libsolidity/codegen/ir/IRGeneratorForStatements.h
@@ -46,6 +46,9 @@ public:
 
 	bool visit(VariableDeclarationStatement const& _variableDeclaration) override;
 	bool visit(Assignment const& _assignment) override;
+	bool visit(ForStatement const& _forStatement) override;
+	bool visit(Continue const& _continueStatement) override;
+	bool visit(Break const& _breakStatement) override;
 	bool visit(Return const& _return) override;
 	void endVisit(BinaryOperation const& _binOp) override;
 	bool visit(FunctionCall const& _funCall) override;