Merge pull request #7770 from ethereum/yul_string_format

[Yul] Format string literals back to quoted string literals

Changelog.md

@@ -6,6 +6,7 @@ Language Features:
 
 
 Compiler Features:
+ * Yul: When compiling via Yul, string literals from the Solidity code are kept as string literals if every character is safely printable.
 
 
 Bugfixes:

libdevcore/CommonData.cpp

@@ -23,6 +23,7 @@
 #include <libdevcore/Exceptions.h>
 #include <libdevcore/Assertions.h>
 #include <libdevcore/Keccak256.h>
+#include <libdevcore/FixedHash.h>
 
 #include <boost/algorithm/string.hpp>
 
@@ -181,3 +182,15 @@ bool dev::isValidDecimal(string const& _string)
 		return false;
 	return true;
 }
+
+// Returns a quoted string if all characters are printable ASCII chars,
+// or its hex representation otherwise.
+std::string dev::formatAsStringOrNumber(std::string const& _value)
+{
+	if (_value.length() <= 32)
+		for (auto const& c: _value)
+			if (c <= 0x1f || c >= 0x7f || c == '"')
+				return "0x" + h256(_value, h256::AlignLeft).hex();
+
+	return "\"" + _value + "\"";
+}

libdevcore/CommonData.h

@@ -290,7 +290,6 @@ void iterateReplacing(std::vector<T>& _vector, F const& _f)
 		_vector = std::move(modifiedVector);
 }
 
-
 namespace detail
 {
 template <typename T, typename F, std::size_t... I>
@@ -355,6 +354,10 @@ std::string getChecksummedAddress(std::string const& _addr);
 bool isValidHex(std::string const& _string);
 bool isValidDecimal(std::string const& _string);
 
+/// @returns a quoted string if all characters are printable ASCII chars,
+/// or its hex representation otherwise.
+std::string formatAsStringOrNumber(std::string const& _value);
+
 template<typename Container, typename Compare>
 bool containerEqual(Container const& _lhs, Container const& _rhs, Compare&& _compare)
 {

libsolidity/codegen/ABIFunctions.cpp

@@ -23,6 +23,7 @@
 #include <libsolidity/codegen/ABIFunctions.h>
 
 #include <libsolidity/codegen/CompilerUtils.h>
+#include <libdevcore/CommonData.h>
 #include <libdevcore/Whiskers.h>
 #include <libdevcore/StringUtils.h>
 
@@ -975,7 +976,7 @@ string ABIFunctions::abiEncodingFunctionStringLiteral(
 			for (size_t i = 0; i < words; ++i)
 			{
 				wordParams[i]["offset"] = to_string(i * 32);
-				wordParams[i]["wordValue"] = "0x" + h256(value.substr(32 * i, 32), h256::AlignLeft).hex();
+				wordParams[i]["wordValue"] = formatAsStringOrNumber(value.substr(32 * i, 32));
 			}
 			templ("word", wordParams);
 			return templ.render();
@@ -990,7 +991,7 @@ string ABIFunctions::abiEncodingFunctionStringLiteral(
 				}
 			)");
 			templ("functionName", functionName);
-			templ("wordValue", "0x" + h256(value, h256::AlignLeft).hex());
+			templ("wordValue", formatAsStringOrNumber(value));
 			return templ.render();
 		}
 	});

libsolidity/codegen/YulUtilFunctions.cpp

@@ -23,6 +23,8 @@
 #include <libsolidity/codegen/MultiUseYulFunctionCollector.h>
 #include <libsolidity/ast/AST.h>
 #include <libsolidity/codegen/CompilerUtils.h>
+
+#include <libdevcore/CommonData.h>
 #include <libdevcore/Whiskers.h>
 #include <libdevcore/StringUtils.h>
 
@@ -1756,7 +1758,7 @@ string YulUtilFunctions::conversionFunctionSpecial(Type const& _from, Type const
 			for (size_t i = 0; i < words; ++i)
 			{
 				wordParams[i]["offset"] = to_string(32 + i * 32);
-				wordParams[i]["wordValue"] = "0x" + h256(data.substr(32 * i, 32), h256::AlignLeft).hex();
+				wordParams[i]["wordValue"] = formatAsStringOrNumber(data.substr(32 * i, 32));
 			}
 			templ("word", wordParams);
 			return templ.render();

test/cmdlineTests/yul_string_format_ascii/input.json

@@ -0,0 +1,17 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() external pure returns (string memory) { return \"abcabc\"; } }"
+		}
+	},
+	"settings":
+	{
+		"outputSelection":
+		{
+			"*": { "*": ["ir"] }
+		}
+	}
+}

test/cmdlineTests/yul_string_format_ascii/output.json

@@ -0,0 +1,161 @@
+{"contracts":{"A":{"C":{"ir":"/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object \"C_10\" {
+    code {
+        mstore(64, 128)
+
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
+
+        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_10_deployed\"))
+
+
+        function allocateMemory(size) -> memPtr {
+            memPtr := mload(64)
+            let newFreePtr := add(memPtr, size)
+            // protect against overflow
+            if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+            mstore(64, newFreePtr)
+        }
+
+        function convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr() -> converted {
+            converted := allocateMemory(64)
+            mstore(converted, 6)
+
+            mstore(add(converted, 32), \"abcabc\")
+
+        }
+
+        function fun_f_9()  -> vloc__4 {
+            for { let return_flag := 1 } return_flag {} {
+                vloc__4 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr()
+                return_flag := 0
+                break
+
+                break
+            }
+        }
+
+    }
+    object \"C_10_deployed\" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_9()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(memPos ,  ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            revert(0, 0)
+
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_string_memory_ptr_to_t_string_memory_ptr_fromStack(value, pos) -> end {
+                let length := array_length_t_string_memory_ptr(value)
+                pos := array_storeLengthForEncoding_t_string_memory_ptr_fromStack(pos, length)
+                copy_memory_to_memory(add(value, 0x20), pos, length)
+                end := add(pos, round_up_to_mul_of_32(length))
+            }
+
+            function abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                mstore(add(headStart, 0), sub(tail, headStart))
+                tail := abi_encode_t_string_memory_ptr_to_t_string_memory_ptr_fromStack(value0,  tail)
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+                mstore(64, newFreePtr)
+            }
+
+            function array_length_t_string_memory_ptr(value) -> length {
+
+
+                length := mload(value)
+
+
+
+            }
+
+            function array_storeLengthForEncoding_t_string_memory_ptr_fromStack(pos, length) -> updated_pos {
+                mstore(pos, length)
+                updated_pos := add(pos, 0x20)
+            }
+
+            function convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr() -> converted {
+                converted := allocateMemory(64)
+                mstore(converted, 6)
+
+                mstore(add(converted, 32), \"abcabc\")
+
+            }
+
+            function copy_memory_to_memory(src, dst, length) {
+                let i := 0
+                for { } lt(i, length) { i := add(i, 32) }
+                {
+                    mstore(add(dst, i), mload(add(src, i)))
+                }
+                if gt(i, length)
+                {
+                    // clear end
+                    mstore(add(dst, length), 0)
+                }
+            }
+
+            function fun_f_9()  -> vloc__4 {
+                for { let return_flag := 1 } return_flag {} {
+                    vloc__4 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_string_memory_ptr()
+                    return_flag := 0
+                    break
+
+                    break
+                }
+            }
+
+            function round_up_to_mul_of_32(value) -> result {
+                result := and(add(value, 31), not(31))
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+        }
+    }
+}
+
+"}}},"sources":{"A":{"id":0}}}

test/cmdlineTests/yul_string_format_ascii_bytes32/input.json

@@ -0,0 +1,17 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() external pure returns (bytes32) { return \"abcabc\"; } }"
+		}
+	},
+	"settings":
+	{
+		"outputSelection":
+		{
+			"*": { "*": ["ir"] }
+		}
+	}
+}

test/cmdlineTests/yul_string_format_ascii_bytes32/output.json

@@ -0,0 +1,114 @@
+{"contracts":{"A":{"C":{"ir":"/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object \"C_10\" {
+    code {
+        mstore(64, 128)
+
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
+
+        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_10_deployed\"))
+
+
+        function convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32() -> converted {
+            converted := 0x6162636162630000000000000000000000000000000000000000000000000000
+        }
+
+        function fun_f_9()  -> vloc__4 {
+            for { let return_flag := 1 } return_flag {} {
+                vloc__4 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32()
+                return_flag := 0
+                break
+
+                break
+            }
+        }
+
+    }
+    object \"C_10_deployed\" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_9()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_bytes32__to_t_bytes32__fromStack(memPos ,  ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            revert(0, 0)
+
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_bytes32_to_t_bytes32_fromStack(value, pos) {
+                mstore(pos, cleanup_t_bytes32(value))
+            }
+
+            function abi_encode_tuple_t_bytes32__to_t_bytes32__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                abi_encode_t_bytes32_to_t_bytes32_fromStack(value0,  add(headStart, 0))
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+                mstore(64, newFreePtr)
+            }
+
+            function cleanup_t_bytes32(value) -> cleaned {
+                cleaned := value
+            }
+
+            function convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32() -> converted {
+                converted := 0x6162636162630000000000000000000000000000000000000000000000000000
+            }
+
+            function fun_f_9()  -> vloc__4 {
+                for { let return_flag := 1 } return_flag {} {
+                    vloc__4 := convert_t_stringliteral_9f0adad0a59b05d2e04a1373342b10b9eb16c57c164c8a3bfcbf46dccee39a21_to_t_bytes32()
+                    return_flag := 0
+                    break
+
+                    break
+                }
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+        }
+    }
+}
+
+"}}},"sources":{"A":{"id":0}}}

test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/input.json

@@ -0,0 +1,17 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() external pure returns (bytes4) { return 0x61626364; } }"
+		}
+	},
+	"settings":
+	{
+		"outputSelection":
+		{
+			"*": { "*": ["ir"] }
+		}
+	}
+}

test/cmdlineTests/yul_string_format_ascii_bytes32_from_number/output.json

@@ -0,0 +1,138 @@
+{"contracts":{"A":{"C":{"ir":"/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object \"C_10\" {
+    code {
+        mstore(64, 128)
+
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
+
+        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_10_deployed\"))
+
+
+        function cleanup_t_rational_1633837924_by_1(value) -> cleaned {
+            cleaned := value
+        }
+
+        function convert_t_rational_1633837924_by_1_to_t_bytes4(value) -> converted {
+            converted := shift_left_224(cleanup_t_rational_1633837924_by_1(value))
+        }
+
+        function fun_f_9()  -> vloc__4 {
+            for { let return_flag := 1 } return_flag {} {
+                let expr_6 := 0x61626364
+                vloc__4 := convert_t_rational_1633837924_by_1_to_t_bytes4(expr_6)
+                return_flag := 0
+                break
+
+                break
+            }
+        }
+
+        function shift_left_224(value) -> newValue {
+            newValue :=
+
+            shl(224, value)
+
+        }
+
+    }
+    object \"C_10_deployed\" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_9()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(memPos ,  ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            revert(0, 0)
+
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_bytes4_to_t_bytes4_fromStack(value, pos) {
+                mstore(pos, cleanup_t_bytes4(value))
+            }
+
+            function abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                abi_encode_t_bytes4_to_t_bytes4_fromStack(value0,  add(headStart, 0))
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+                mstore(64, newFreePtr)
+            }
+
+            function cleanup_t_bytes4(value) -> cleaned {
+                cleaned := and(value, 0xffffffff00000000000000000000000000000000000000000000000000000000)
+            }
+
+            function cleanup_t_rational_1633837924_by_1(value) -> cleaned {
+                cleaned := value
+            }
+
+            function convert_t_rational_1633837924_by_1_to_t_bytes4(value) -> converted {
+                converted := shift_left_224(cleanup_t_rational_1633837924_by_1(value))
+            }
+
+            function fun_f_9()  -> vloc__4 {
+                for { let return_flag := 1 } return_flag {} {
+                    let expr_6 := 0x61626364
+                    vloc__4 := convert_t_rational_1633837924_by_1_to_t_bytes4(expr_6)
+                    return_flag := 0
+                    break
+
+                    break
+                }
+            }
+
+            function shift_left_224(value) -> newValue {
+                newValue :=
+
+                shl(224, value)
+
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+        }
+    }
+}
+
+"}}},"sources":{"A":{"id":0}}}

test/cmdlineTests/yul_string_format_ascii_long/input.json

@@ -0,0 +1,17 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() external pure returns (string memory) { return \"abcdabcdcafecafeabcdabcdcafecafeffffzzzzoooo0123456789,.<,>.?:;'[{]}|`~!@#$%^&*()-_=+\"; } }"
+		}
+	},
+	"settings":
+	{
+		"outputSelection":
+		{
+			"*": { "*": ["ir"] }
+		}
+	}
+}

test/cmdlineTests/yul_string_format_ascii_long/output.json

@@ -0,0 +1,169 @@
+{"contracts":{"A":{"C":{"ir":"/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object \"C_10\" {
+    code {
+        mstore(64, 128)
+
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
+
+        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_10_deployed\"))
+
+
+        function allocateMemory(size) -> memPtr {
+            memPtr := mload(64)
+            let newFreePtr := add(memPtr, size)
+            // protect against overflow
+            if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+            mstore(64, newFreePtr)
+        }
+
+        function convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr() -> converted {
+            converted := allocateMemory(128)
+            mstore(converted, 85)
+
+            mstore(add(converted, 32), \"abcdabcdcafecafeabcdabcdcafecafe\")
+
+            mstore(add(converted, 64), \"ffffzzzzoooo0123456789,.<,>.?:;'\")
+
+            mstore(add(converted, 96), \"[{]}|`~!@#$%^&*()-_=+\")
+
+        }
+
+        function fun_f_9()  -> vloc__4 {
+            for { let return_flag := 1 } return_flag {} {
+                vloc__4 := convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr()
+                return_flag := 0
+                break
+
+                break
+            }
+        }
+
+    }
+    object \"C_10_deployed\" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_9()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(memPos ,  ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            revert(0, 0)
+
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_string_memory_ptr_to_t_string_memory_ptr_fromStack(value, pos) -> end {
+                let length := array_length_t_string_memory_ptr(value)
+                pos := array_storeLengthForEncoding_t_string_memory_ptr_fromStack(pos, length)
+                copy_memory_to_memory(add(value, 0x20), pos, length)
+                end := add(pos, round_up_to_mul_of_32(length))
+            }
+
+            function abi_encode_tuple_t_string_memory_ptr__to_t_string_memory_ptr__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                mstore(add(headStart, 0), sub(tail, headStart))
+                tail := abi_encode_t_string_memory_ptr_to_t_string_memory_ptr_fromStack(value0,  tail)
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+                mstore(64, newFreePtr)
+            }
+
+            function array_length_t_string_memory_ptr(value) -> length {
+
+
+                length := mload(value)
+
+
+
+            }
+
+            function array_storeLengthForEncoding_t_string_memory_ptr_fromStack(pos, length) -> updated_pos {
+                mstore(pos, length)
+                updated_pos := add(pos, 0x20)
+            }
+
+            function convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr() -> converted {
+                converted := allocateMemory(128)
+                mstore(converted, 85)
+
+                mstore(add(converted, 32), \"abcdabcdcafecafeabcdabcdcafecafe\")
+
+                mstore(add(converted, 64), \"ffffzzzzoooo0123456789,.<,>.?:;'\")
+
+                mstore(add(converted, 96), \"[{]}|`~!@#$%^&*()-_=+\")
+
+            }
+
+            function copy_memory_to_memory(src, dst, length) {
+                let i := 0
+                for { } lt(i, length) { i := add(i, 32) }
+                {
+                    mstore(add(dst, i), mload(add(src, i)))
+                }
+                if gt(i, length)
+                {
+                    // clear end
+                    mstore(add(dst, length), 0)
+                }
+            }
+
+            function fun_f_9()  -> vloc__4 {
+                for { let return_flag := 1 } return_flag {} {
+                    vloc__4 := convert_t_stringliteral_d6604f85ac07e2b33103a620b3d3d75b0473c7214912beded67b9b624d41c571_to_t_string_memory_ptr()
+                    return_flag := 0
+                    break
+
+                    break
+                }
+            }
+
+            function round_up_to_mul_of_32(value) -> result {
+                result := and(add(value, 31), not(31))
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+        }
+    }
+}
+
+"}}},"sources":{"A":{"id":0}}}

test/cmdlineTests/yul_string_format_hex/input.json

@@ -0,0 +1,17 @@
+{
+	"language": "Solidity",
+	"sources":
+	{
+		"A":
+		{
+			"content": "pragma solidity >=0.0; contract C { function f() external pure returns (bytes4) { return 0xaabbccdd; } }"
+		}
+	},
+	"settings":
+	{
+		"outputSelection":
+		{
+			"*": { "*": ["ir"] }
+		}
+	}
+}

test/cmdlineTests/yul_string_format_hex/output.json

@@ -0,0 +1,138 @@
+{"contracts":{"A":{"C":{"ir":"/*******************************************************
+ *                       WARNING                       *
+ *  Solidity to Yul compilation is still EXPERIMENTAL  *
+ *       It can result in LOSS OF FUNDS or worse       *
+ *                !USE AT YOUR OWN RISK!               *
+ *******************************************************/
+
+
+object \"C_10\" {
+    code {
+        mstore(64, 128)
+
+        // Begin state variable initialization for contract \"C\" (0 variables)
+        // End state variable initialization for contract \"C\".
+
+
+        codecopy(0, dataoffset(\"C_10_deployed\"), datasize(\"C_10_deployed\"))
+        return(0, datasize(\"C_10_deployed\"))
+
+
+        function cleanup_t_rational_2864434397_by_1(value) -> cleaned {
+            cleaned := value
+        }
+
+        function convert_t_rational_2864434397_by_1_to_t_bytes4(value) -> converted {
+            converted := shift_left_224(cleanup_t_rational_2864434397_by_1(value))
+        }
+
+        function fun_f_9()  -> vloc__4 {
+            for { let return_flag := 1 } return_flag {} {
+                let expr_6 := 0xaabbccdd
+                vloc__4 := convert_t_rational_2864434397_by_1_to_t_bytes4(expr_6)
+                return_flag := 0
+                break
+
+                break
+            }
+        }
+
+        function shift_left_224(value) -> newValue {
+            newValue :=
+
+            shl(224, value)
+
+        }
+
+    }
+    object \"C_10_deployed\" {
+        code {
+            mstore(64, 128)
+
+            if iszero(lt(calldatasize(), 4))
+            {
+                let selector := shift_right_224_unsigned(calldataload(0))
+                switch selector
+
+                case 0x26121ff0
+                {
+                    // f()
+                    if callvalue() { revert(0, 0) }
+                    abi_decode_tuple_(4, calldatasize())
+                    let ret_0 :=  fun_f_9()
+                    let memPos := allocateMemory(0)
+                    let memEnd := abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(memPos ,  ret_0)
+                    return(memPos, sub(memEnd, memPos))
+                }
+
+                default {}
+            }
+            revert(0, 0)
+
+
+            function abi_decode_tuple_(headStart, dataEnd)   {
+                if slt(sub(dataEnd, headStart), 0) { revert(0, 0) }
+
+            }
+
+            function abi_encode_t_bytes4_to_t_bytes4_fromStack(value, pos) {
+                mstore(pos, cleanup_t_bytes4(value))
+            }
+
+            function abi_encode_tuple_t_bytes4__to_t_bytes4__fromStack(headStart , value0) -> tail {
+                tail := add(headStart, 32)
+
+                abi_encode_t_bytes4_to_t_bytes4_fromStack(value0,  add(headStart, 0))
+
+            }
+
+            function allocateMemory(size) -> memPtr {
+                memPtr := mload(64)
+                let newFreePtr := add(memPtr, size)
+                // protect against overflow
+                if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
+                mstore(64, newFreePtr)
+            }
+
+            function cleanup_t_bytes4(value) -> cleaned {
+                cleaned := and(value, 0xffffffff00000000000000000000000000000000000000000000000000000000)
+            }
+
+            function cleanup_t_rational_2864434397_by_1(value) -> cleaned {
+                cleaned := value
+            }
+
+            function convert_t_rational_2864434397_by_1_to_t_bytes4(value) -> converted {
+                converted := shift_left_224(cleanup_t_rational_2864434397_by_1(value))
+            }
+
+            function fun_f_9()  -> vloc__4 {
+                for { let return_flag := 1 } return_flag {} {
+                    let expr_6 := 0xaabbccdd
+                    vloc__4 := convert_t_rational_2864434397_by_1_to_t_bytes4(expr_6)
+                    return_flag := 0
+                    break
+
+                    break
+                }
+            }
+
+            function shift_left_224(value) -> newValue {
+                newValue :=
+
+                shl(224, value)
+
+            }
+
+            function shift_right_224_unsigned(value) -> newValue {
+                newValue :=
+
+                shr(224, value)
+
+            }
+
+        }
+    }
+}
+
+"}}},"sources":{"A":{"id":0}}}

test/libsolidity/semanticTests/viaYul/string_format.sol

@@ -0,0 +1,13 @@
+contract C {
+	function f1() external pure returns (string memory) { return "abcabc"; }
+	function f2() external pure returns (string memory) { return "abcabc`~12345677890- _=+!@#$%^&*()[{]}|;:',<.>?"; }
+	function g() external pure returns (bytes32) { return "abcabc"; }
+	function h() external pure returns (bytes4) { return 0xcafecafe; }
+}
+// ====
+// compileViaYul: only
+// ----
+// f1() -> 0x20, 6, left(0x616263616263)
+// f2() -> 32, 47, 44048183223289766195424279195050628400112610419087780792899004030957505095210, 18165586057823232067963737336409268114628061002662705707816940456850361417728
+// g() -> left(0x616263616263)
+// h() -> left(0xcafecafe)