From 8aa4568b10e6bde427fd5e84dfa21c01e74c78d9 Mon Sep 17 00:00:00 2001
From: Djordje Mijovic <djordje.mijovic@gmail.com>
Date: Fri, 11 Dec 2020 11:07:22 +0100
Subject: [PATCH] [Sol->Yul] Implementing conversion from calldata slices to
 memory arrays.
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Co-authored-by: Kamil Śliwak <kamil.sliwak@codepoets.it>
---
 libsolidity/ast/Types.cpp                | 14 +++++++-------
 libsolidity/codegen/YulUtilFunctions.cpp |  7 +++++--
 2 files changed, 12 insertions(+), 9 deletions(-)

diff --git a/libsolidity/ast/Types.cpp b/libsolidity/ast/Types.cpp
index d32650383..5c7c91126 100644
--- a/libsolidity/ast/Types.cpp
+++ b/libsolidity/ast/Types.cpp
@@ -2074,13 +2074,13 @@ std::unique_ptr<ReferenceType> ArrayType::copyForLocation(DataLocation _location
 
 BoolResult ArraySliceType::isImplicitlyConvertibleTo(Type const& _other) const
 {
-	if (
-		m_arrayType.dataStoredIn(DataLocation::CallData) &&
-		m_arrayType.isDynamicallySized() &&
-		m_arrayType.isImplicitlyConvertibleTo(_other)
-	)
-		return true;
-	return (*this) == _other;
+	return
+		(*this) == _other ||
+		(
+			m_arrayType.dataStoredIn(DataLocation::CallData) &&
+			m_arrayType.isDynamicallySized() &&
+			m_arrayType.isImplicitlyConvertibleTo(_other)
+		);
 }
 
 string ArraySliceType::richIdentifier() const
diff --git a/libsolidity/codegen/YulUtilFunctions.cpp b/libsolidity/codegen/YulUtilFunctions.cpp
index db92a7a0a..6c1784551 100644
--- a/libsolidity/codegen/YulUtilFunctions.cpp
+++ b/libsolidity/codegen/YulUtilFunctions.cpp
@@ -2852,8 +2852,8 @@ string YulUtilFunctions::conversionFunction(Type const& _from, Type const& _to)
 		solAssert(_from.dataStoredIn(DataLocation::CallData), "");
 		solAssert(_to.category() == Type::Category::Array, "");
 
-		ArraySliceType const& fromType = dynamic_cast<ArraySliceType const&>(_from);
-		ArrayType const& targetType = dynamic_cast<ArrayType const&>(_to);
+		auto const& fromType = dynamic_cast<ArraySliceType const&>(_from);
+		auto const& targetType = dynamic_cast<ArrayType const&>(_to);
 
 		solAssert(!fromType.arrayType().baseType()->isDynamicallyEncoded(), "");
 		solAssert(
@@ -2861,6 +2861,9 @@ string YulUtilFunctions::conversionFunction(Type const& _from, Type const& _to)
 			"Converting arrays of different type is not possible"
 		);
 
+		if (!targetType.dataStoredIn(DataLocation::CallData))
+			return arrayConversionFunction(fromType.arrayType(), targetType);
+
 		string const functionName =
 			"convert_" +
 			_from.identifier() +