Copying of arrays from storage to memory.

libsolidity/codegen/ABIFunctions.h

@@ -126,7 +126,6 @@ public:
 	/// stack slot, it takes exactly that number of values.
 	std::string tupleDecoder(TypePointers const& _types, bool _fromMemory = false);
 
-private:
 	struct EncodingOptions
 	{
 		/// Pad/signextend value types and bytes/string to multiples of 32 bytes.
@@ -146,6 +145,7 @@ private:
 		std::string toFunctionNameSuffix() const;
 	};
 
+	/// Internal encoding function that is also used by some copying routines.
 	/// @returns the name of the ABI encoding function with the given type
 	/// and queues the generation of the function to the requested functions.
 	/// @param _fromStack if false, the input value was just loaded from storage
@@ -155,6 +155,7 @@ private:
 		Type const& _targetType,
 		EncodingOptions const& _options
 	);
+	/// Internal encoding function that is also used by some copying routines.
 	/// @returns the name of a function that internally calls `abiEncodingFunction`
 	/// but always returns the updated encoding position, even if the type is
 	/// statically encoded.
@@ -163,6 +164,8 @@ private:
 		Type const& _targetType,
 		EncodingOptions const& _options
 	);
+
+private:
 	/// Part of @a abiEncodingFunction for array target type and given calldata array.
 	/// Uses calldatacopy and does not perform cleanup or validation and can therefore only
 	/// be used for byte arrays and arrays with the base type uint256 or bytes32.

libsolidity/codegen/YulUtilFunctions.cpp

@@ -1446,6 +1446,70 @@ string YulUtilFunctions::nextArrayElementFunction(ArrayType const& _type)
 	});
 }
 
+string YulUtilFunctions::copyArrayFromStorageToMemoryFunction(ArrayType const& _from, ArrayType const& _to)
+{
+	solAssert(_from.dataStoredIn(DataLocation::Storage), "");
+	solAssert(_to.dataStoredIn(DataLocation::Memory), "");
+	solAssert(_from.isDynamicallySized() == _to.isDynamicallySized(), "");
+	if (!_from.isDynamicallySized())
+		solAssert(_from.length() == _to.length(), "");
+
+	string functionName = "copy_array_from_storage_to_memory_" + _from.identifier();
+
+	return m_functionCollector.createFunction(functionName, [&]() {
+		if (_from.baseType()->isValueType())
+		{
+			solAssert(_from.baseType() == _to.baseType(), "");
+			ABIFunctions abi(m_evmVersion, m_revertStrings, m_functionCollector);
+			return Whiskers(R"(
+				function <functionName>(slot) -> memptr {
+					memptr := <allocateTemp>()
+					let end := <encode>(slot, memptr)
+					mstore(<freeMemoryPointer>, end)
+				}
+			)")
+			("functionName", functionName)
+			("allocateTemp", allocationTemporaryMemoryFunction())
+			(
+				"encode",
+				abi.abiEncodeAndReturnUpdatedPosFunction(_from, _to, ABIFunctions::EncodingOptions{})
+			)
+			("freeMemoryPointer", to_string(CompilerUtils::freeMemoryPointer))
+			.render();
+		}
+		else
+		{
+			solAssert(_to.memoryStride() == 32, "");
+			solAssert(_to.baseType()->dataStoredIn(DataLocation::Memory), "");
+			solAssert(_from.baseType()->dataStoredIn(DataLocation::Storage), "");
+			solAssert(!_from.isByteArray(), "");
+			solAssert(*_to.withLocation(DataLocation::Storage, _from.isPointer()) == _from, "");
+			return Whiskers(R"(
+				function <functionName>(slot) -> memptr {
+					let length := <lengthFunction>(slot)
+					memptr := <allocateArray>(length)
+					let mpos := memptr
+					<?dynamic>mpos := add(mpos, 0x20)</dynamic>
+					let spos := <arrayDataArea>(slot)
+					for { let i := 0 } lt(i, length) { i := add(i, 1) } {
+						mstore(mpos, <convert>(spos))
+						mpos := add(mpos, 0x20)
+						spos := add(spos, <baseStorageSize>)
+					}
+				}
+			)")
+			("functionName", functionName)
+			("lengthFunction", arrayLengthFunction(_from))
+			("allocateArray", allocateMemoryArrayFunction(_to))
+			("arrayDataArea", arrayDataAreaFunction(_from))
+			("dynamic", _to.isDynamicallySized())
+			("convert", conversionFunction(*_from.baseType(), *_to.baseType()))
+			("baseStorageSize", _from.baseType()->storageSize().str())
+			.render();
+		}
+	});
+}
+
 string YulUtilFunctions::mappingIndexAccessFunction(MappingType const& _mappingType, Type const& _keyType)
 {
 	solAssert(_keyType.sizeOnStack() <= 1, "");
@@ -2261,8 +2325,12 @@ string YulUtilFunctions::conversionFunction(Type const& _from, Type const& _to)
 					break;
 				case DataLocation::Memory:
 					// Copy the array to a free position in memory, unless it is already in memory.
-					solUnimplementedAssert(from.location() == DataLocation::Memory, "Not implemented yet.");
+					if (from.location() == DataLocation::Memory)
-					body = "converted := value";
+						body = "converted := value";
+					else if (from.location() == DataLocation::CallData)
+						solUnimplemented("Conversion of calldata types not yet implemented.");
+					else
+						body = "converted := " + copyArrayFromStorageToMemoryFunction(from, to) + "(value)";
 					break;
 				case DataLocation::CallData:
 					solUnimplemented("Conversion of calldata types not yet implemented.");

libsolidity/codegen/YulUtilFunctions.h

@@ -220,6 +220,10 @@ public:
 	/// Only works for memory arrays, calldata arrays and storage arrays that every item occupies one or multiple full slots.
 	std::string nextArrayElementFunction(ArrayType const& _type);
 
+	/// @returns the name of a function that allocates a memory array and copies the contents
+	/// of the storage array into it.
+	std::string copyArrayFromStorageToMemoryFunction(ArrayType const& _from, ArrayType const& _to);
+
 	/// @returns the name of a function that performs index access for mappings.
 	/// @param _mappingType the type of the mapping
 	/// @param _keyType the type of the value provided

test/libsolidity/semanticTests/array/array_copy_storage_abi_signed.sol

@@ -16,5 +16,7 @@ contract c {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // test() -> 0x20, 0x8, -1, -1, 8, -16, -2, 6, 8, -1

test/libsolidity/semanticTests/array/array_copy_storage_to_memory.sol

@@ -6,5 +6,7 @@ contract C {
         return (b[0], b.length);
     }
 }
+// ====
+// compileViaYul: also
 // ----
 // f() -> 1, 3

test/libsolidity/semanticTests/array/byte_array_pop_copy_long.sol

@@ -8,5 +8,7 @@ contract c {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // test() -> 0x20, 29, 0x0303030303030303030303030303030303030303030303030303030303000000

test/libsolidity/semanticTests/array/byte_array_pop_masking_long.sol

@@ -8,5 +8,7 @@ contract c {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // test() -> 0x20, 33, 0x303030303030303030303030303030303030303030303030303030303030303, 0x0300000000000000000000000000000000000000000000000000000000000000

test/libsolidity/semanticTests/array/copying/storage_memory_nested.sol

@@ -0,0 +1,21 @@
+contract C {
+    uint72[5][] a;
+
+    function f() public returns (uint72, uint72, uint72, uint72, uint72, uint72, uint72) {
+        for (uint i = 0; i < 4; i++)
+            a.push();
+        a[0][0] = 1;
+        a[0][3] = 2;
+        a[1][1] = 3;
+        a[1][4] = 4;
+        a[2][0] = 5;
+        a[3][2] = 6;
+        a[3][3] = 7;
+        uint72[5][] memory m = a;
+        return (m[0][0], m[0][3], m[1][1], m[1][4], m[2][0], m[3][2], m[3][3]);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 1, 2, 3, 4, 5, 6, 7

test/libsolidity/semanticTests/array/copying/storage_memory_nested_bytes.sol

@@ -0,0 +1,13 @@
+pragma experimental ABIEncoderV2;
+contract C {
+    bytes[] a;
+
+    function f() public returns (bytes[] memory) {
+        a.push("abc");
+        a.push("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVXYZabcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVXYZ");
+        bytes[] memory m = a;
+        return m;
+    }
+}
+// ----
+// f() -> 0x20, 0x02, 0x40, 0x80, 3, 0x6162630000000000000000000000000000000000000000000000000000000000, 0x99, 44048183304486788312148433451363384677562265908331949128489393215789685032262, 32241931068525137014058842823026578386641954854143559838526554899205067598957, 49951309422467613961193228765530489307475214998374779756599339590522149884499, 0x54555658595a6162636465666768696a6b6c6d6e6f707172737475767778797a, 0x4142434445464748494a4b4c4d4e4f5051525354555658595a00000000000000

test/libsolidity/semanticTests/array/copying/storage_memory_nested_from_pointer.sol

@@ -0,0 +1,22 @@
+contract C {
+    uint72[5][] a;
+
+    function f() public returns (uint72, uint72, uint72, uint72, uint72, uint72, uint72) {
+        for (uint i = 0; i < 4; i++)
+            a.push();
+        a[0][0] = 1;
+        a[0][3] = 2;
+        a[1][1] = 3;
+        a[1][4] = 4;
+        a[2][0] = 5;
+        a[3][2] = 6;
+        a[3][3] = 7;
+        uint72[5][] storage a_ = a;
+        uint72[5][] memory m = a_;
+        return (m[0][0], m[0][3], m[1][1], m[1][4], m[2][0], m[3][2], m[3][3]);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 1, 2, 3, 4, 5, 6, 7

test/libsolidity/semanticTests/array/copying/storage_memory_nested_struct.sol

@@ -0,0 +1,26 @@
+contract C {
+    struct T { uint8 x; uint8 y; uint[] z; }
+    T[3][] a;
+
+    function f() public returns (uint8, uint8, uint, uint, uint, uint8, uint8, uint, uint, uint) {
+        a.push();
+        a.push();
+        a[0][1].x = 11;
+        a[0][1].y = 12;
+        a[0][1].z.push(1);
+        a[0][1].z.push(2);
+        a[0][1].z.push(3);
+        a[1][2].x = 21;
+        a[1][2].y = 22;
+        a[1][2].z.push(4);
+        a[1][2].z.push(5);
+        a[1][2].z.push(6);
+        T[3][] memory m = a;
+        return (
+            m[0][1].x, m[0][1].y, m[0][1].z[0], m[0][1].z[1], m[0][1].z[2],
+            m[1][2].x, m[1][2].y, m[1][2].z[0], m[1][2].z[1], m[1][2].z[2]
+        );
+    }
+}
+// ----
+// f() -> 11, 0x0c, 1, 2, 3, 0x15, 22, 4, 5, 6

test/libsolidity/semanticTests/array/copying/storage_memory_packed.sol

@@ -0,0 +1,15 @@
+contract C {
+    uint8[33] a;
+
+    function f() public returns (uint8, uint8, uint8) {
+        a[0] = 2;
+        a[16] = 3;
+        a[32] = 4;
+        uint8[33] memory m = a;
+        return (m[0], m[16], m[32]);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 2, 3, 4

test/libsolidity/semanticTests/array/copying/storage_memory_packed_dyn.sol

@@ -0,0 +1,17 @@
+contract C {
+    uint8[] a;
+
+    function f() public returns (uint8, uint8, uint8) {
+        for (uint i = 0; i < 33; i++)
+            a.push(7);
+        a[0] = 2;
+        a[16] = 3;
+        a[32] = 4;
+        uint8[] memory m = a;
+        return (m[0], m[16], m[32]);
+    }
+}
+// ====
+// compileViaYul: also
+// ----
+// f() -> 2, 3, 4

test/libsolidity/semanticTests/array/memory_arrays_dynamic_index_access_write.sol

@@ -15,5 +15,7 @@ contract Test {
         return set(data)[1];
     }
 }
+// ====
+// compileViaYul: also
 // ----
 // f() -> 0x20, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x07

test/libsolidity/semanticTests/builtinFunctions/iterated_keccak256_with_bytes.sol

@@ -8,5 +8,7 @@ contract c {
         return keccak256(abi.encodePacked("b", keccak256(data), "a"));
     }
 }
+// ====
+// compileViaYul: also
 // ----
 // foo() -> 0xb338eefce206f9f57b83aa738deecd5326dc4b72dd81ee6a7c621a6facb7acdc

test/libsolidity/semanticTests/builtinFunctions/keccak256_with_bytes.sol

@@ -9,5 +9,7 @@ contract c {
     }
 }
 
+// ====
+// compileViaYul: also
 // ----
 // foo() -> true

test/libsolidity/semanticTests/expressions/conditional_expression_storage_memory_2.sol

@@ -23,6 +23,8 @@ contract test {
         return ret;
     }
 }
+// ====
+// compileViaYul: also
 // ----
 // f(bool): true -> 1
 // f(bool): false -> 2