Implementing struct copying from calldata to storage

Changelog.md

@@ -2,7 +2,7 @@
 
 Language Features:
  * Allow function definitions outside of contracts, behaving much like internal library functions.
-
+ * Code generator: Implementing copying structs from calldata to storage.
 
 Compiler Features:
  * SMTChecker: Add underflow and overflow as verification conditions in the CHC engine.

libsolidity/codegen/LValue.cpp

@@ -357,7 +357,15 @@ void StorageItem::storeValue(Type const& _sourceType, SourceLocation const& _loc
 				"Struct assignment with conversion."
 			);
 			solAssert(!structType.containsNestedMapping(), "");
-			solAssert(sourceType.location() != DataLocation::CallData, "Structs in calldata not supported.");
+			if (sourceType.location() == DataLocation::CallData)
+			{
+				solAssert(sourceType.sizeOnStack() == 1, "");
+				solAssert(structType.sizeOnStack() == 1, "");
+				m_context << Instruction::DUP2 << Instruction::DUP2;
+				m_context.callYulFunction(m_context.utilFunctions().updateStorageValueFunction(structType, &sourceType, 0), 2, 0);
+			}
+			else
+			{
 				for (auto const& member: structType.members(nullptr))
 				{
 					// assign each member that can live outside of storage
@@ -390,6 +398,7 @@ void StorageItem::storeValue(Type const& _sourceType, SourceLocation const& _loc
 					// stack: source_ref target_ref target_off source_value... target_member_ref target_member_byte_off
 					StorageItem(m_context, *memberType).storeValue(*sourceMemberType, _location, true);
 				}
+			}
 			// stack layout: source_ref target_ref
 			solAssert(sourceType.sizeOnStack() == 1, "Unexpected source size.");
 			if (_move)

libsolidity/codegen/YulUtilFunctions.cpp

@@ -1553,11 +1553,6 @@ string YulUtilFunctions::updateStorageValueFunction(
 
 				Whiskers templ(R"(
 					function <functionName>(slot, value) {
-						<?fromCalldata>
-							let valueMem := <convertToMemory>(value)
-						<!fromCalldata>
-							let valueMem := value
-						</fromCalldata>
 						<#member>
 						{
 							<updateMemberCall>
@@ -1566,12 +1561,6 @@ string YulUtilFunctions::updateStorageValueFunction(
 					}
 				)");
 				templ("functionName", functionName);
-				templ("fromCalldata", fromStructType.location() == DataLocation::CallData);
-				if (fromStructType.location() == DataLocation::CallData)
-					templ("convertToMemory", conversionFunction(
-						fromStructType,
-						*TypeProvider::structType(toStructType.structDefinition(), DataLocation::Memory)
-					));
 
 				MemberList::MemberMap toStructMembers = toStructType.nativeMembers(nullptr);
 				MemberList::MemberMap fromStructMembers = fromStructType.nativeMembers(nullptr);
@@ -1581,9 +1570,10 @@ string YulUtilFunctions::updateStorageValueFunction(
 				{
 					solAssert(toStructMembers[i].type->memoryHeadSize() == 32, "");
 					bool isStruct = toStructMembers[i].type->category() == Type::Category::Struct;
+					bool fromCalldata = fromStructType.location() == DataLocation::CallData;
 					auto const& [slotDiff, offset] = toStructType.storageOffsetsOfMember(toStructMembers[i].name);
 					memberParams[i]["updateMemberCall"] = Whiskers(R"(
-						let memberValue := <loadFromMemory>(add(valueMem, <memberMemoryOffset>))
+						let memberValue := <loadFromMemoryOrCalldata>(add(value, <memberOffset>))
 						<updateMember>(add(slot, <memberStorageSlotDiff>), <?hasOffset><memberStorageOffset>,</hasOffset> memberValue)
 					)")
 					("hasOffset", !isStruct)
@@ -1595,8 +1585,12 @@ string YulUtilFunctions::updateStorageValueFunction(
 					)
 					("memberStorageSlotDiff", slotDiff.str())
 					("memberStorageOffset", to_string(offset))
-					("memberMemoryOffset", fromStructType.memoryOffsetOfMember(fromStructMembers[i].name).str())
+					("memberOffset",
-					("loadFromMemory", readFromMemory(*fromStructMembers[i].type))
+						fromCalldata ?
+							to_string(fromStructType.calldataOffsetOfMember(fromStructMembers[i].name)) :
+							fromStructType.memoryOffsetOfMember(fromStructMembers[i].name).str()
+					)
+					("loadFromMemoryOrCalldata", readFromMemoryOrCalldata(*fromStructMembers[i].type, fromCalldata))
 					.render();
 				}
 				templ("member", memberParams);

test/libsolidity/semanticTests/structs/calldata/calldata_struct_to_storage.sol

@@ -3,10 +3,11 @@ pragma experimental ABIEncoderV2;
 contract C {
     struct S {
         uint256 a;
-        uint256 b;
+        uint64 b;
         bytes2 c;
     }
 
+    uint[153] r;
     S s;
 
     function f(uint32 a, S calldata c, uint256 b) external returns (uint256, uint256, byte) {
@@ -16,6 +17,6 @@ contract C {
 }
 
 // ====
-// compileViaYul: true
+// compileViaYul: also
 // ----
-// f(uint32, (uint256, uint256, bytes2), uint256): 1, 42, 23, "ab", 1 -> 42, 23, "b"
+// f(uint32, (uint256, uint64, bytes2), uint256): 1, 42, 23, "ab", 1 -> 42, 23, "b"