returnSize assigned according to truth value of returnInfo.dynamicReturnSize

libsolidity/codegen/ReturnInfo.cpp

@@ -54,4 +54,6 @@ ReturnInfo::ReturnInfo(EVMVersion const& _evmVersion, FunctionType const& _funct
 				estimatedReturnSize += retType->decodingType()->calldataEncodedSize();
 		}
 	}
+	if (dynamicReturnSize)
+		solAssert(estimatedReturnSize == 0);
 }

libsolidity/codegen/ir/IRGeneratorForStatements.cpp

@@ -2505,6 +2505,8 @@ void IRGeneratorForStatements::appendExternalFunctionCall(
 			appendCode() << "mstore(add(" << m_utils.allocateUnboundedFunction() << "() , " << to_string(returnInfo.estimatedReturnSize) << "), 0)\n";
 	}
 
+	// NOTE: When the expected size of returndata is static, we pass that in to the call opcode and it gets copied automatically.
+    // When it's dynamic, we get zero from estimatedReturnSize() instead and then we need an explicit returndatacopy().
 	Whiskers templ(R"(
 		<?checkExtcodesize>
 			if iszero(extcodesize(<address>)) { <revertNoCode>() }
@@ -2514,22 +2516,29 @@ void IRGeneratorForStatements::appendExternalFunctionCall(
 		mstore(<pos>, <shl28>(<funSel>))
 		let <end> := <encodeArgs>(add(<pos>, 4) <argumentString>)
 
-		let <success> := <call>(<gas>, <address>, <?hasValue> <value>, </hasValue> <pos>, sub(<end>, <pos>), <pos>, <reservedReturnSize>)
+		let <success> := <call>(<gas>, <address>, <?hasValue> <value>, </hasValue> <pos>, sub(<end>, <pos>), <pos>, <staticReturndataSize>)
 		<?noTryCall>
 			if iszero(<success>) { <forwardingRevert>() }
 		</noTryCall>
 		<?+retVars> let <retVars> </+retVars>
 		if <success> {
-			<?dynamicReturnSize>
+			<?isReturndataSizeDynamic>
-				// copy dynamic return data out
+				let <returnDataSizeVar> := returndatasize()
-				returndatacopy(<pos>, 0, returndatasize())
+				returndatacopy(<pos>, 0, <returnDataSizeVar>)
-			</dynamicReturnSize>
+			<!isReturndataSizeDynamic>
+				let <returnDataSizeVar> := <staticReturndataSize>
+				<?supportsReturnData>
+					if gt(<returnDataSizeVar>, returndatasize()) {
+						<returnDataSizeVar> := returndatasize()
+					}
+				</supportsReturnData>
+			</isReturndataSizeDynamic>
 
 			// update freeMemoryPointer according to dynamic return size
-			<finalizeAllocation>(<pos>, <returnSize>)
+			<finalizeAllocation>(<pos>, <returnDataSizeVar>)
 
 			// decode return parameters from external try-call into retVars
-			<?+retVars> <retVars> := </+retVars> <abiDecode>(<pos>, add(<pos>, <returnSize>))
+			<?+retVars> <retVars> := </+retVars> <abiDecode>(<pos>, add(<pos>, <returnDataSizeVar>))
 		}
 	)");
 	templ("revertNoCode", m_utils.revertReasonIfDebugFunction("Target contract does not contain code"));
@@ -2558,21 +2567,18 @@ void IRGeneratorForStatements::appendExternalFunctionCall(
 	templ("funSel", IRVariable(_functionCall.expression()).part("functionSelector").name());
 	templ("address", IRVariable(_functionCall.expression()).part("address").name());
 
-	// Always use the actual return length, and not our calculated expected length, if returndatacopy is supported.
+	if (returnInfo.dynamicReturnSize)
-	// This ensures it can catch badly formatted input from external calls.
+		solAssert(m_context.evmVersion().supportsReturndata());
-	if (m_context.evmVersion().supportsReturndata())
+	templ("returnDataSizeVar", m_context.newYulVariable());
-		templ("returnSize", "returndatasize()");
+	templ("staticReturndataSize", to_string(returnInfo.estimatedReturnSize));
-	else
+	templ("supportsReturnData", m_context.evmVersion().supportsReturndata());
-		templ("returnSize", to_string(returnInfo.estimatedReturnSize));
-
-	templ("reservedReturnSize", returnInfo.dynamicReturnSize ? "0" : to_string(returnInfo.estimatedReturnSize));
 
 	string const retVars = IRVariable(_functionCall).commaSeparatedList();
 	templ("retVars", retVars);
 	solAssert(retVars.empty() == returnInfo.returnTypes.empty());
 
 	templ("abiDecode", m_context.abiFunctions().tupleDecoder(returnInfo.returnTypes, true));
-	templ("dynamicReturnSize", returnInfo.dynamicReturnSize);
+	templ("isReturndataSizeDynamic", returnInfo.dynamicReturnSize);
 
 	templ("noTryCall", !_functionCall.annotation().tryCall);
 

test/cmdlineTests/standard_debug_info_in_evm_asm_via_ir_location/output.json

@@ -265,34 +265,39 @@ sub_0: assembly {
       return
         /* \"C\":403:411  this.f() */
     tag_36:
-        /* \"C\":79:428  contract C... */
       swap1
       swap2
       pop
-        /* \"C\":403:411  this.f() */
+      0x20
+      swap1
       returndatasize
+      dup3
+      gt
+      tag_41
+      jumpi
+    tag_42:
         /* \"C\":79:428  contract C... */
       0x1f
+      dup3
       add
       not(0x1f)
       and
-      dup3
+      dup4
       add
       swap1
       0xffffffffffffffff
       dup3
       gt
-      dup4
+      dup5
       dup4
       lt
       or
-      tag_41
+      tag_43
       jumpi
       pop
-      tag_40
       swap3
         /* \"C\":403:411  this.f() */
-      tag_43
+      tag_45
         /* \"C\":392:422  stateVar + this.f() + immutVar */
       tag_39
         /* \"C\":79:428  contract C... */
@@ -301,34 +306,41 @@ sub_0: assembly {
       tag_38
         /* \"C\":79:428  contract C... */
       swap4
+      tag_40
+      swap7
       0x40
       mstore
         /* \"C\":403:411  this.f() */
-      returndatasize
       dup2
       add
       swap1
       tag_6
       jump\t// in
-    tag_43:
+    tag_45:
       swap3
       pop
       swap3
       jump(tag_37)
         /* \"C\":79:428  contract C... */
-    tag_41:
+    tag_43:
       shl(0xe0, 0x4e487b71)
       dup2
       mstore
       mstore(0x04, 0x41)
       0x24
-      swap4
+      swap5
+      pop
+      swap3
       pop
-      swap2
       pop
       pop
       revert
         /* \"C\":403:411  this.f() */
+    tag_41:
+      returndatasize
+      swap2
+      pop
+      jump(tag_42)
     tag_34:
         /* \"C\":79:428  contract C... */
       swap3
@@ -345,10 +357,10 @@ sub_0: assembly {
       swap1
       revert
     tag_32:
-      tag_44
+      tag_46
       tag_4
       jump\t// in
-    tag_44:
+    tag_46:
       jump(tag_33)
         /* \"C\":117:119  41 */
     tag_4:
@@ -373,9 +385,9 @@ sub_0: assembly {
       dup5
       sgt
       and
-      tag_45
+      tag_47
       jumpi
-    tag_46:
+    tag_48:
       shl(0xff, 0x01)
       dup3
       swap1
@@ -383,25 +395,25 @@ sub_0: assembly {
       dup4
       slt
       and
-      tag_47
+      tag_49
       jumpi
       add
       swap1
       jump\t// out
-    tag_47:
+    tag_49:
-      tag_49
+      tag_51
       tag_4
       jump\t// in
-    tag_49:
+    tag_51:
       add
       swap1
       jump\t// out
-    tag_45:
+    tag_47:
-      tag_50
+      tag_52
       tag_4
       jump\t// in
-    tag_50:
+    tag_52:
-      jump(tag_46)
+      jump(tag_48)
         /* \"C\":79:428  contract C... */
     tag_6:
       swap1
@@ -410,12 +422,12 @@ sub_0: assembly {
       swap2
       sub
       slt
-      tag_51
+      tag_53
       jumpi
       mload
       swap1
       jump\t// out
-    tag_51:
+    tag_53:
       pop
       pop
       0x00
@@ -732,34 +744,39 @@ sub_0: assembly {
       return
         /* \"C\":403:411  this.f() */
     tag_36:
-        /* \"D\":91:166  contract D is C(3)... */
       swap1
       swap2
       pop
-        /* \"C\":403:411  this.f() */
+      0x20
+      swap1
       returndatasize
+      dup3
+      gt
+      tag_41
+      jumpi
+    tag_42:
         /* \"D\":91:166  contract D is C(3)... */
       0x1f
+      dup3
       add
       not(0x1f)
       and
-      dup3
+      dup4
       add
       swap1
       0xffffffffffffffff
       dup3
       gt
-      dup4
+      dup5
       dup4
       lt
       or
-      tag_41
+      tag_43
       jumpi
       pop
-      tag_40
       swap3
         /* \"C\":403:411  this.f() */
-      tag_43
+      tag_45
         /* \"C\":392:422  stateVar + this.f() + immutVar */
       tag_39
         /* \"D\":91:166  contract D is C(3)... */
@@ -768,34 +785,41 @@ sub_0: assembly {
       tag_38
         /* \"D\":91:166  contract D is C(3)... */
       swap4
+      tag_40
+      swap7
       0x40
       mstore
         /* \"C\":403:411  this.f() */
-      returndatasize
       dup2
       add
       swap1
       tag_6
       jump\t// in
-    tag_43:
+    tag_45:
       swap3
       pop
       swap3
       jump(tag_37)
         /* \"D\":91:166  contract D is C(3)... */
-    tag_41:
+    tag_43:
       shl(0xe0, 0x4e487b71)
       dup2
       mstore
       mstore(0x04, 0x41)
       0x24
-      swap4
+      swap5
+      pop
+      swap3
       pop
-      swap2
       pop
       pop
       revert
         /* \"C\":403:411  this.f() */
+    tag_41:
+      returndatasize
+      swap2
+      pop
+      jump(tag_42)
     tag_34:
         /* \"D\":91:166  contract D is C(3)... */
       swap3
@@ -812,10 +836,10 @@ sub_0: assembly {
       swap1
       revert
     tag_32:
-      tag_44
+      tag_46
       tag_4
       jump\t// in
-    tag_44:
+    tag_46:
       jump(tag_33)
         /* \"C\":117:119  41 */
     tag_4:
@@ -840,9 +864,9 @@ sub_0: assembly {
       dup5
       sgt
       and
-      tag_45
+      tag_47
       jumpi
-    tag_46:
+    tag_48:
       shl(0xff, 0x01)
       dup3
       swap1
@@ -850,25 +874,25 @@ sub_0: assembly {
       dup4
       slt
       and
-      tag_47
+      tag_49
       jumpi
       add
       swap1
       jump\t// out
-    tag_47:
+    tag_49:
-      tag_49
+      tag_51
       tag_4
       jump\t// in
-    tag_49:
+    tag_51:
       add
       swap1
       jump\t// out
-    tag_45:
+    tag_47:
-      tag_50
+      tag_52
       tag_4
       jump\t// in
-    tag_50:
+    tag_52:
-      jump(tag_46)
+      jump(tag_48)
         /* \"D\":91:166  contract D is C(3)... */
     tag_6:
       swap1
@@ -877,12 +901,12 @@ sub_0: assembly {
       swap2
       sub
       slt
-      tag_51
+      tag_53
       jumpi
       mload
       swap1
       jump\t// out
-    tag_51:
+    tag_53:
       pop
       pop
       0x00

test/cmdlineTests/standard_debug_info_in_yul_location/output.json

@@ -563,18 +563,24 @@ object \"C_54\" {
                 let expr_47
                 if _12 {
 
+                    let _13 := 32
+
+                    if gt(_13, returndatasize()) {
+                        _13 := returndatasize()
+                    }
+
                     // update freeMemoryPointer according to dynamic return size
-                    finalize_allocation(_10, returndatasize())
+                    finalize_allocation(_10, _13)
 
                     // decode return parameters from external try-call into retVars
-                    expr_47 :=  abi_decode_tuple_t_int256_fromMemory(_10, add(_10, returndatasize()))
+                    expr_47 :=  abi_decode_tuple_t_int256_fromMemory(_10, add(_10, _13))
                 }
                 /// @src 0:399:418  \"stateVar + this.f()\"
                 let expr_48 := checked_add_t_int256(expr_44, expr_47)
 
                 /// @src 0:421:429  \"immutVar\"
-                let _13 := loadimmutable(\"8\")
+                let _14 := loadimmutable(\"8\")
-                let expr_49 := _13
+                let expr_49 := _14
                 /// @src 0:399:429  \"stateVar + this.f() + immutVar\"
                 let expr_50 := checked_add_t_int256(expr_48, expr_49)
 
@@ -718,8 +724,10 @@ object \"C_54\" {
                 /// @src 0:410:418  \"this.f()\"
                 if _4
                 {
+                    let _5 := 32
+                    if gt(_5, returndatasize()) { _5 := returndatasize() }
                     /// @src 0:79:435  \"contract C...\"
-                    let newFreePtr := add(_3, and(add(/** @src 0:410:418  \"this.f()\" */ returndatasize(), /** @src 0:79:435  \"contract C...\" */ 31), not(31)))
+                    let newFreePtr := add(_3, and(add(_5, 31), not(31)))
                     if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, _3))
                     {
                         mstore(_1, shl(224, 0x4e487b71))
@@ -728,7 +736,7 @@ object \"C_54\" {
                     }
                     mstore(64, newFreePtr)
                     /// @src 0:410:418  \"this.f()\"
-                    expr := abi_decode_int256_fromMemory(_3, add(_3, returndatasize()))
+                    expr := abi_decode_int256_fromMemory(_3, add(_3, _5))
                 }
                 /// @src 0:399:418  \"stateVar + this.f()\"
                 let expr_1 := checked_add_int256(ret, expr)
@@ -1402,18 +1410,24 @@ object \"D_72\" {
                 let expr_47
                 if _12 {
 
+                    let _13 := 32
+
+                    if gt(_13, returndatasize()) {
+                        _13 := returndatasize()
+                    }
+
                     // update freeMemoryPointer according to dynamic return size
-                    finalize_allocation(_10, returndatasize())
+                    finalize_allocation(_10, _13)
 
                     // decode return parameters from external try-call into retVars
-                    expr_47 :=  abi_decode_tuple_t_int256_fromMemory(_10, add(_10, returndatasize()))
+                    expr_47 :=  abi_decode_tuple_t_int256_fromMemory(_10, add(_10, _13))
                 }
                 /// @src 0:399:418  \"stateVar + this.f()\"
                 let expr_48 := checked_add_t_int256(expr_44, expr_47)
 
                 /// @src 0:421:429  \"immutVar\"
-                let _13 := loadimmutable(\"8\")
+                let _14 := loadimmutable(\"8\")
-                let expr_49 := _13
+                let expr_49 := _14
                 /// @src 0:399:429  \"stateVar + this.f() + immutVar\"
                 let expr_50 := checked_add_t_int256(expr_48, expr_49)
 
@@ -1565,8 +1579,10 @@ object \"D_72\" {
                 /// @src 0:410:418  \"this.f()\"
                 if _4
                 {
+                    let _5 := 32
+                    if gt(_5, returndatasize()) { _5 := returndatasize() }
                     /// @src 1:91:166  \"contract D is C(3)...\"
-                    let newFreePtr := add(_3, and(add(/** @src 0:410:418  \"this.f()\" */ returndatasize(), /** @src 1:91:166  \"contract D is C(3)...\" */ 31), not(31)))
+                    let newFreePtr := add(_3, and(add(_5, 31), not(31)))
                     if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, _3))
                     {
                         mstore(_1, shl(224, 0x4e487b71))
@@ -1575,7 +1591,7 @@ object \"D_72\" {
                     }
                     mstore(64, newFreePtr)
                     /// @src 0:410:418  \"this.f()\"
-                    expr := abi_decode_int256_fromMemory(_3, add(_3, returndatasize()))
+                    expr := abi_decode_int256_fromMemory(_3, add(_3, _5))
                 }
                 /// @src 0:399:418  \"stateVar + this.f()\"
                 let expr_1 := checked_add_int256(ret, expr)

test/libsolidity/semanticTests/abiEncoderV1/abi_encode_calldata_slice.sol

@@ -60,10 +60,10 @@ contract C {
 // compileViaYul: also
 // ----
 // test_bytes() ->
-// gas irOptimized: 371847
+// gas irOptimized: 371919
 // gas legacy: 418955
 // gas legacyOptimized: 326783
 // test_uint256() ->
-// gas irOptimized: 522929
+// gas irOptimized: 523001
 // gas legacy: 586784
 // gas legacyOptimized: 451529

test/libsolidity/semanticTests/abiEncoderV1/struct/struct_storage_ptr.sol

@@ -26,6 +26,6 @@ contract C {
 // ----
 // library: L
 // f() -> 8, 7, 1, 2, 7, 12
-// gas irOptimized: 167672
+// gas irOptimized: 167696
 // gas legacy: 169347
 // gas legacyOptimized: 167269

test/libsolidity/semanticTests/abiEncoderV2/abi_encode_calldata_slice.sol

@@ -61,10 +61,10 @@ contract C {
 // compileViaYul: also
 // ----
 // test_bytes() ->
-// gas irOptimized: 371847
+// gas irOptimized: 371919
 // gas legacy: 418955
 // gas legacyOptimized: 326783
 // test_uint256() ->
-// gas irOptimized: 522929
+// gas irOptimized: 523001
 // gas legacy: 586784
 // gas legacyOptimized: 451529

test/libsolidity/semanticTests/abiEncoderV2/abi_encode_v2_in_function_inherited_in_v1_contract.sol

@@ -32,6 +32,6 @@ contract C is B {
 // compileViaYul: also
 // ----
 // test() -> 77
-// gas irOptimized: 119895
+// gas irOptimized: 119919
 // gas legacy: 155093
 // gas legacyOptimized: 111550

test/libsolidity/semanticTests/abiEncoderV2/calldata_array.sol

@@ -21,6 +21,6 @@ contract C {
 // f(uint256[][1]): 32, 32, 0 -> true
 // f(uint256[][1]): 32, 32, 1, 42 -> true
 // f(uint256[][1]): 32, 32, 8, 421, 422, 423, 424, 425, 426, 427, 428 -> true
-// gas irOptimized: 171838
+// gas irOptimized: 171842
 // gas legacy: 141644
 // gas legacyOptimized: 121532

test/libsolidity/semanticTests/array/fixed_arrays_as_return_type.sol

@@ -21,6 +21,6 @@ contract B {
 // compileViaYul: also
 // ----
 // f() -> 2, 3, 4, 5, 6, 1000, 1001, 1002, 1003, 1004
-// gas irOptimized: 130097
+// gas irOptimized: 130152
 // gas legacy: 234943
 // gas legacyOptimized: 132863

test/libsolidity/semanticTests/array/function_array_cross_calls.sol

@@ -45,6 +45,6 @@ contract C {
 // compileViaYul: also
 // ----
 // test() -> 5, 6, 7
-// gas irOptimized: 290567
+// gas irOptimized: 298983
 // gas legacy: 452172
 // gas legacyOptimized: 285017

test/libsolidity/semanticTests/array/reusing_memory.sol

@@ -26,6 +26,6 @@ contract Main {
 // compileViaYul: also
 // ----
 // f(uint256): 0x34 -> 0x46bddb1178e94d7f2892ff5f366840eb658911794f2c3a44c450aa2c505186c1
-// gas irOptimized: 113552
+// gas irOptimized: 113598
 // gas legacy: 126596
 // gas legacyOptimized: 113823

test/libsolidity/semanticTests/constructor/arrays_in_constructors.sol

@@ -26,6 +26,6 @@ contract Creator {
 // compileViaYul: also
 // ----
 // f(uint256,address[]): 7, 0x40, 10, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 -> 7, 8
-// gas irOptimized: 443921
+// gas irOptimized: 443960
 // gas legacy: 590683
 // gas legacyOptimized: 448326

test/libsolidity/semanticTests/constructor/bytes_in_constructors_packer.sol

@@ -26,6 +26,6 @@ contract Creator {
 // compileViaYul: also
 // ----
 // f(uint256,bytes): 7, 0x40, 78, "abcdefghijklmnopqrstuvwxyzabcdef", "ghijklmnopqrstuvwxyzabcdefghijkl", "mnopqrstuvwxyz" -> 7, "h"
-// gas irOptimized: 300765
+// gas irOptimized: 300804
 // gas legacy: 428917
 // gas legacyOptimized: 298128

test/libsolidity/semanticTests/events/event_emit_from_other_contract.sol

@@ -17,7 +17,7 @@ contract C {
 // compileViaYul: also
 // ----
 // constructor() ->
-// gas irOptimized: 177344
+// gas irOptimized: 173672
 // gas legacy: 250376
 // gas legacyOptimized: 174522
 // deposit(bytes32), 18 wei: 0x1234 ->

test/libsolidity/semanticTests/functionCall/creation_function_call_with_args.sol

@@ -17,7 +17,7 @@ contract D {
 // compileViaYul: also
 // ----
 // constructor(): 2 ->
-// gas irOptimized: 200295
+// gas irOptimized: 203967
 // gas legacy: 245842
 // gas legacyOptimized: 195676
 // f() -> 2

test/libsolidity/semanticTests/functionCall/creation_function_call_with_salt.sol

@@ -18,7 +18,7 @@ contract D {
 // compileViaYul: also
 // ----
 // constructor(): 2 ->
-// gas irOptimized: 200458
+// gas irOptimized: 204130
 // gas legacy: 246202
 // gas legacyOptimized: 195914
 // f() -> 2

test/libsolidity/semanticTests/functionCall/external_call_to_nonexisting.sol

@@ -25,7 +25,7 @@ contract C {
 // compileViaYul: also
 // ----
 // constructor(), 1 ether ->
-// gas irOptimized: 308423
+// gas irOptimized: 315341
 // gas legacy: 465314
 // gas legacyOptimized: 304481
 // f(uint256): 0 -> FAILURE

test/libsolidity/semanticTests/functionCall/external_call_to_nonexisting_debugstrings.sol

@@ -27,7 +27,7 @@ contract C {
 // revertStrings: debug
 // ----
 // constructor(), 1 ether ->
-// gas irOptimized: 445767
+// gas irOptimized: 452673
 // gas legacy: 834272
 // gas legacyOptimized: 510004
 // f(uint256): 0 -> FAILURE, hex"08c379a0", 0x20, 37, "Target contract does not contain", " code"

test/libsolidity/semanticTests/functionCall/failed_create.sol

@@ -18,7 +18,7 @@ contract C {
 // compileViaYul: also
 // ----
 // constructor(), 20 wei
-// gas irOptimized: 213663
+// gas irOptimized: 219285
 // gas legacy: 294569
 // gas legacyOptimized: 174699
 // f(uint256): 20 -> 1370859564726510389319704988634906228201275401179
@@ -26,7 +26,7 @@ contract C {
 // f(uint256): 20 -> FAILURE
 // x() -> 1
 // stack(uint256): 1023 -> FAILURE
-// gas irOptimized: 304303
+// gas irOptimized: 314884
 // gas legacy: 483942
 // gas legacyOptimized: 298807
 // x() -> 1

test/libsolidity/semanticTests/functionCall/gas_and_value_basic.sol

@@ -41,7 +41,7 @@ contract test {
 // compileViaYul: also
 // ----
 // constructor(), 20 wei ->
-// gas irOptimized: 274154
+// gas irOptimized: 283040
 // gas legacy: 402654
 // gas legacyOptimized: 274470
 // sendAmount(uint256): 5 -> 5

test/libsolidity/semanticTests/functionCall/gas_and_value_brace_syntax.sol

@@ -40,7 +40,7 @@ contract test {
 // compileViaYul: also
 // ----
 // constructor(), 20 wei ->
-// gas irOptimized: 274154
+// gas irOptimized: 283040
 // gas legacy: 402654
 // gas legacyOptimized: 274470
 // sendAmount(uint256): 5 -> 5

test/libsolidity/semanticTests/functionCall/return_size_bigger_than_expected.sol

@@ -0,0 +1,31 @@
+interface ShortReturn {
+    function f() external pure returns (bytes32);
+}
+contract LongReturn {
+    function f() external pure returns (uint[20] memory) {}
+}
+
+contract Test {
+    function test() public returns (uint) {
+        LongReturn longReturn = new LongReturn();
+        uint freeMemoryBefore;
+        assembly {
+            freeMemoryBefore := mload(0x40)
+        }
+
+        ShortReturn(address(longReturn)).f();
+
+        uint freeMemoryAfter;
+
+        assembly {
+            freeMemoryAfter := mload(0x40)
+        }
+
+        return freeMemoryAfter - freeMemoryBefore;
+    }
+}
+// ====
+// compileViaYul: true
+// ----
+// test() -> 0x20
+// gas legacy: 131966

test/libsolidity/semanticTests/functionCall/return_size_shorter_than_expected.sol

@@ -0,0 +1,32 @@
+interface LongReturn {
+    function f() external pure returns (uint[20] memory);
+}
+contract ShortReturn {
+    function f() external pure returns (bytes32) {}
+}
+
+contract Test {
+    function test() public returns (uint) {
+        ShortReturn shortReturn = new ShortReturn();
+        uint freeMemoryBefore;
+        assembly {
+            freeMemoryBefore := mload(0x40)
+        }
+
+        LongReturn(address(shortReturn)).f();
+
+        uint freeMemoryAfter;
+
+        assembly {
+            freeMemoryAfter := mload(0x40)
+        }
+
+        return freeMemoryAfter - freeMemoryBefore;
+    }
+}
+// ====
+// EVMVersion: <=homestead
+// compileViaYul: true
+// ----
+// test() -> 0x0500
+// gas legacy: 131966

test/libsolidity/semanticTests/functionCall/return_size_shorter_than_expected_evm_version_after_homestead.sol

@@ -0,0 +1,34 @@
+interface LongReturn {
+    function f() external pure returns (uint[20] memory);
+}
+contract ShortReturn {
+    function f() external pure returns (bytes32) {}
+}
+
+contract Test {
+    function test() public returns (uint) {
+        ShortReturn shortReturn = new ShortReturn();
+        uint freeMemoryBefore;
+        assembly {
+            freeMemoryBefore := mload(0x40)
+        }
+
+        // This reverts. The external call succeeds but ABI decoding fails due to the returned
+        // `bytes32` being much shorter than the expected `uint[20]`.
+        LongReturn(address(shortReturn)).f();
+
+        uint freeMemoryAfter;
+
+        assembly {
+            freeMemoryAfter := mload(0x40)
+        }
+
+        return freeMemoryAfter - freeMemoryBefore;
+    }
+}
+// ====
+// EVMVersion: >homestead
+// compileViaYul: true
+// ----
+// test() -> FAILURE
+// gas legacy: 131966

test/libsolidity/semanticTests/immutable/multi_creation.sol

@@ -29,7 +29,7 @@ contract C {
 // compileViaYul: also
 // ----
 // f() -> 3, 7, 5
-// gas irOptimized: 127302
+// gas irOptimized: 127347
 // gas legacy: 151334
 // gas legacyOptimized: 125166
 // x() -> 7

test/libsolidity/semanticTests/inheritance/inherited_function_calldata_memory_interface.sol

@@ -25,6 +25,6 @@ contract B {
 // compileViaYul: also
 // ----
 // g() -> 42
-// gas irOptimized: 111770
+// gas irOptimized: 111794
 // gas legacy: 185053
 // gas legacyOptimized: 114598

test/libsolidity/semanticTests/inheritance/value_for_constructor.sol

@@ -42,7 +42,7 @@ contract Main {
 // compileViaYul: also
 // ----
 // constructor(), 22 wei ->
-// gas irOptimized: 276469
+// gas irOptimized: 284287
 // gas legacy: 402045
 // gas legacyOptimized: 266772
 // getFlag() -> true

test/libsolidity/semanticTests/isoltestTesting/balance_other_contract.sol

@@ -18,7 +18,7 @@ contract ClientReceipt {
 // compileViaYul: also
 // ----
 // constructor(), 2000 wei ->
-// gas irOptimized: 184076
+// gas irOptimized: 188162
 // gas legacy: 235195
 // gas legacyOptimized: 176766
 // balance -> 1500

test/libsolidity/semanticTests/libraries/internal_types_in_library.sol

@@ -25,6 +25,6 @@ contract Test {
 // ----
 // library: Lib
 // f() -> 4, 0x11
-// gas irOptimized: 115822
+// gas irOptimized: 115874
 // gas legacy: 135952
 // gas legacyOptimized: 119643

test/libsolidity/semanticTests/libraries/using_library_mappings_public.sol

@@ -22,6 +22,6 @@ contract Test {
 // ----
 // library: Lib
 // f() -> 1, 0, 0x2a, 0x17, 0, 0x63
-// gas irOptimized: 119757
+// gas irOptimized: 119561
 // gas legacy: 124793
 // gas legacyOptimized: 119694

test/libsolidity/semanticTests/libraries/using_library_mappings_return.sol

@@ -20,6 +20,6 @@ contract Test {
 // ----
 // library: Lib
 // f() -> 1, 0, 0x2a, 0x17, 0, 0x63
-// gas irOptimized: 120471
+// gas irOptimized: 120572
 // gas legacy: 125245
 // gas legacyOptimized: 120153

test/libsolidity/semanticTests/libraries/using_library_structs.sol

@@ -23,5 +23,5 @@ contract Test {
 // ----
 // library: Lib
 // f() -> 7, 8
-// gas irOptimized: 101869
+// gas irOptimized: 101820
 // gas legacy: 101504

test/libsolidity/semanticTests/salted_create/salted_create_with_value.sol

@@ -22,6 +22,6 @@ contract A {
 // compileViaYul: also
 // ----
 // f(), 10 ether -> 3007, 3008, 3009
-// gas irOptimized: 272338
+// gas irOptimized: 272413
 // gas legacy: 422501
 // gas legacyOptimized: 287472

test/libsolidity/semanticTests/userDefinedValueType/calldata.sol

@@ -51,7 +51,7 @@ contract C {
 // compileViaYul: also
 // ----
 // test_f() -> true
-// gas irOptimized: 122413
+// gas irOptimized: 122364
 // gas legacy: 126168
 // gas legacyOptimized: 123199
 // test_g() -> true

test/libsolidity/semanticTests/various/senders_balance.sol

@@ -19,7 +19,7 @@ contract D {
 // compileViaYul: also
 // ----
 // constructor(), 27 wei ->
-// gas irOptimized: 175261
+// gas irOptimized: 178933
 // gas legacy: 222977
 // gas legacyOptimized: 169779
 // f() -> 27

test/libsolidity/semanticTests/various/skip_dynamic_types_for_structs.sol

@@ -22,6 +22,6 @@ contract C {
 // compileViaYul: also
 // ----
 // g() -> 2, 6
-// gas irOptimized: 178822
+// gas irOptimized: 178812
 // gas legacy: 180762
 // gas legacyOptimized: 179481

test/libsolidity/semanticTests/various/value_complex.sol

@@ -22,7 +22,7 @@ contract test {
 // compileViaYul: also
 // ----
 // constructor(), 20 wei ->
-// gas irOptimized: 185891
+// gas irOptimized: 192113
 // gas legacy: 265006
 // gas legacyOptimized: 182842
 // sendAmount(uint256): 5 -> 8

test/libsolidity/semanticTests/various/value_insane.sol

@@ -21,7 +21,7 @@ contract test {
 // compileViaYul: also
 // ----
 // constructor(), 20 wei ->
-// gas irOptimized: 187835
+// gas irOptimized: 194261
 // gas legacy: 266728
 // gas legacyOptimized: 184762
 // sendAmount(uint256): 5 -> 8

test/libsolidity/semanticTests/viaYul/copy_struct_invalid_ir_bug.sol

@@ -23,6 +23,6 @@ contract C {
 // compileViaYul: also
 // ----
 // f() ->
-// gas irOptimized: 113096
+// gas irOptimized: 112998
 // gas legacy: 112937
 // gas legacyOptimized: 112608