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Tests and Changelog

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This commit is contained in:
Harikrishnan Mulackal 2020-07-03 19:50:27 +05:30
parent 5c6e7f03b4
commit bbf15c9af3
26 changed files with 750 additions and 6 deletions
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1
Changelog.md
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@ -6,6 +6,7 @@ Language Features:
Compiler Features:
* Standard JSON Interface: Do not run EVM bytecode code generation, if only Yul IR or EWasm output is requested.
* Yul: Report error when using non-string literals for ``datasize()``, ``dataoffset()``, ``linkersymbol()``, ``loadimmutable()``, ``setimmutable()``.
* Yul Optimizer: LoopInvariantCodeMotion can move reading operations outside for-loops as long as the affected area is not modified inside the loop.
Bugfixes:
* Optimizer: Keep side-effects of ``x`` in ``byte(a, shr(b, x))`` even if the constants ``a`` and ``b`` would make the expression zero unconditionally. This optimizer rule is very hard if not impossible to trigger in a way that it can result in invalid code, though.

1
test/cmdlineTests/optimizer_array_sload/args Normal file
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@ -0,0 +1 @@
--optimize --ir-optimized --metadata-hash none

15
test/cmdlineTests/optimizer_array_sload/input.sol Normal file
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@ -0,0 +1,15 @@
// SPDX-License-Identifier: GPL-3.0
pragma solidity >=0.0;
contract Arraysum {
uint256[] values;
function sumArray() public view returns(uint) {
uint sum = 0;
// The optimizer should read the length of the array only once, because
// LoopInvariantCodeMotion can move the `sload` corresponding to the length outside of the
// loop.
for(uint i = 0; i < values.length; i++)
sum += values[i];
}
}

83
test/cmdlineTests/optimizer_array_sload/output Normal file
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@ -0,0 +1,83 @@
Optimized IR:
/*******************************************************
* WARNING *
* Solidity to Yul compilation is still EXPERIMENTAL *
* It can result in LOSS OF FUNDS or worse *
* !USE AT YOUR OWN RISK! *
*******************************************************/
object "Arraysum_33" {
code {
{
mstore(64, 128)
if callvalue() { revert(0, 0) }
let _1 := datasize("Arraysum_33_deployed")
codecopy(0, dataoffset("Arraysum_33_deployed"), _1)
return(0, _1)
}
}
object "Arraysum_33_deployed" {
code {
{
mstore(64, 128)
if iszero(lt(calldatasize(), 4))
{
let _1 := 0
if eq(0x81d73423, shr(224, calldataload(_1)))
{
if callvalue() { revert(_1, _1) }
if slt(add(calldatasize(), not(3)), _1) { revert(_1, _1) }
let vloc_sum := _1
let vloc_i := _1
let _2 := sload(_1)
for { }
lt(vloc_i, _2)
{
vloc_i := increment_t_uint256(vloc_i)
}
{
let _3, _4 := storage_array_index_access_t_array$_t_uint256_$dyn_storage(_1, vloc_i)
vloc_sum := checked_add_t_uint256(vloc_sum, extract_from_storage_value_dynamict_uint256(sload(_3), _4))
}
let memPos := allocateMemory(_1)
return(memPos, sub(abi_encode_tuple_t_uint256__to_t_uint256__fromStack(memPos, _1), memPos))
}
}
revert(0, 0)
}
function abi_encode_tuple_t_uint256__to_t_uint256__fromStack(headStart, value0) -> tail
{
tail := add(headStart, 32)
mstore(headStart, value0)
}
function allocateMemory(size) -> memPtr
{
memPtr := mload(64)
let newFreePtr := add(memPtr, size)
if or(gt(newFreePtr, 0xffffffffffffffff), lt(newFreePtr, memPtr)) { revert(0, 0) }
mstore(64, newFreePtr)
}
function checked_add_t_uint256(x, y) -> sum
{
if gt(x, not(y)) { revert(sum, sum) }
sum := add(x, y)
}
function extract_from_storage_value_dynamict_uint256(slot_value, offset) -> value
{
value := shr(mul(offset, 8), slot_value)
}
function increment_t_uint256(value) -> ret
{
if gt(value, not(1)) { revert(ret, ret) }
ret := add(value, 1)
}
function storage_array_index_access_t_array$_t_uint256_$dyn_storage(array, index) -> slot, offset
{
if iszero(lt(index, sload(array))) { invalid() }
mstore(slot, array)
slot := add(keccak256(slot, 0x20), index)
offset := offset
}
}
}
}

15
test/cmdlineTests/optimizer_user_yul/output
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@ -48,19 +48,22 @@ tag_5:
0x02
/* "optimizer_user_yul/input.sol":359:371 sstore(2, 3) */
sstore
/* "optimizer_user_yul/input.sol":376:509 for { } sload(5) { } {... */
tag_6:
/* "optimizer_user_yul/input.sol":390:391 5 */
0x05
/* "optimizer_user_yul/input.sol":384:392 sload(5) */
sload
tag_9
jumpi
jump(tag_8)
tag_9:
iszero
/* "optimizer_user_yul/input.sol":376:509 for { } sload(5) { } {... */
tag_6:
/* "optimizer_user_yul/input.sol":384:392 sload(5) */
dup1
/* "optimizer_user_yul/input.sol":376:509 for { } sload(5) { } {... */
tag_8
jumpi
jump(tag_6)
tag_8:
/* "optimizer_user_yul/input.sol":380:383 { } */
pop
/* "optimizer_user_yul/input.sol":340:513 {... */
pop
/* "optimizer_user_yul/input.sol":60:518 contract C... */

23
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/complex_move.yul Normal file
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@ -0,0 +1,23 @@
{
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := extcodesize(keccak256(mul(mload(inv), 3), 32))
a := add(x, 1)
sstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// let x := extcodesize(keccak256(mul(mload(inv), 3), 32))
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// a := add(x, 1)
// sstore(a, inv)
// }
// }

30
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/create_sload.yul Normal file
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@ -0,0 +1,30 @@
{
function g() -> x { x := create(100, 0, 32) }
function f() -> x { x := mload(0) }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
// cannot be moved because of the create call in g()
let q := sload(5)
let r := g()
// This can be moved
let z := f()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function g() -> x
// { x := create(100, 0, 32) }
// function f() -> x_1
// { x_1 := mload(0) }
// let b := 1
// let a := 1
// let z := f()
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let q := sload(5)
// let r := g()
// }
// }

24
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/move_memory_function.yul Normal file
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@ -0,0 +1,24 @@
{
function g() -> x { x := add(sload(mload(x)), 1) }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := mload(g())
let s := keccak256(g(), 32)
let q := g()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function g() -> x
// { x := add(sload(mload(x)), 1) }
// let b := 1
// let a := 1
// let t := mload(g())
// let s := keccak256(g(), 32)
// let q := g()
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { }
// }

25
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/move_state_function.yul Normal file
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@ -0,0 +1,25 @@
{
function f() -> x { x := mload(g()) }
function g() -> x { x := add(sload(x), 1) }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := extcodesize(f())
let q := g()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := mload(g()) }
// function g() -> x_1
// { x_1 := add(sload(x_1), 1) }
// let b := 1
// let a := 1
// let t := extcodesize(f())
// let q := g()
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { }
// }

25
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/move_storage_function.yul Normal file
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@ -0,0 +1,25 @@
{
function f() -> x { x := g() }
function g() -> x { x := add(x, 1) }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := sload(f())
let q := g()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// { x_1 := add(x_1, 1) }
// let b := 1
// let a := 1
// let t := sload(f())
// let q := g()
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { }
// }

29
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_immovables.yul Normal file
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@ -0,0 +1,29 @@
{
let a := 1
function f() -> x {invalid()}
function g() -> y {return(0, 0)}
for { let i := 1 } iszero(eq(i, 10)) { a := add(i, 1) } {
let b := f()
let c := gas()
let d := g()
let e := sload(g())
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let a := 1
// function f() -> x
// { invalid() }
// function g() -> y
// { return(0, 0) }
// let i := 1
// for { } iszero(eq(i, 10)) { a := add(i, 1) }
// {
// let b := f()
// let c := gas()
// let d := g()
// let e := sload(g())
// }
// }

38
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_memory.yul Normal file
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@ -0,0 +1,38 @@
{
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := keccak256(inv, 32)
a := add(x, 1)
mstore(a, inv)
}
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
// mload prevents moving of extcodesize
let x := extcodesize(mload(mul(inv, 3)))
a := add(x, 1)
mstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let x := keccak256(inv, 32)
// a := add(x, 1)
// mstore(a, inv)
// }
// let a_1 := 1
// let inv_2 := add(b, 42)
// for { } iszero(eq(a_1, 10)) { a_1 := add(a_1, 1) }
// {
// let x_3 := extcodesize(mload(mul(inv_2, 3)))
// a_1 := add(x_3, 1)
// mstore(a_1, inv_2)
// }
// }

29
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_memory_loop.yul Normal file
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@ -0,0 +1,29 @@
{
function f() -> x { x := g() }
function g() -> x { for {} 1 {} {} }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := mload(f())
let q := g()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// {
// for { } 1 { }
// { }
// }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let t := mload(f())
// let q := g()
// }
// }

35
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_memory_msize.yul Normal file
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@ -0,0 +1,35 @@
{
let b := 1
let c := msize() // prevents moving keccak and mload
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := keccak256(inv, 32)
a := add(x, 1)
}
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := extcodesize(mload(mul(inv, 3)))
a := add(x, 1)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let c := msize()
// let a := 1
// let inv := add(b, 42)
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let x := keccak256(inv, 32)
// a := add(x, 1)
// }
// let a_1 := 1
// let inv_2 := add(b, 42)
// for { } iszero(eq(a_1, 10)) { a_1 := add(a_1, 1) }
// {
// let x_3 := extcodesize(mload(mul(inv_2, 3)))
// a_1 := add(x_3, 1)
// }
// }

62
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_state.yul Normal file
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@ -0,0 +1,62 @@
{
let b := 1
// invalidates state in post
for { let a := 1 } iszero(eq(a, 10)) {pop(call(2, 0x01, 2, 0x00, 32, 0x010, 32))} {
let inv := add(b, 42)
let x := extcodesize(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
pop(create(0x08, 0x00, 0x02)) // invalidates state
let x := extcodesize(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
// invalidates state in loop-condition
for { let a := 1 } iszero(create(0x08, 0x00, 0x02)) { a := add(a, 1)} {
let inv := add(b, 42)
let x := extcodesize(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// for { }
// iszero(eq(a, 10))
// {
// pop(call(2, 0x01, 2, 0x00, 32, 0x010, 32))
// }
// {
// let x := extcodesize(mul(inv, 3))
// a := add(x, 1)
// mstore(a, inv)
// }
// let a_1 := 1
// let inv_2 := add(b, 42)
// for { } iszero(eq(a_1, 10)) { a_1 := add(a_1, 1) }
// {
// pop(create(0x08, 0x00, 0x02))
// let x_3 := extcodesize(mul(inv_2, 3))
// a_1 := add(x_3, 1)
// mstore(a_1, inv_2)
// }
// let a_4 := 1
// let inv_5 := add(b, 42)
// for { } iszero(create(0x08, 0x00, 0x02)) { a_4 := add(a_4, 1) }
// {
// let x_6 := extcodesize(mul(inv_5, 3))
// a_4 := add(x_6, 1)
// mstore(a_4, inv_5)
// }
// }

32
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_state_function.yul Normal file
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@ -0,0 +1,32 @@
{
function f() -> x { x := g() }
function g() -> x {
x := add(x, 1)
sstore(0x00, 0x00)
}
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := extcodesize(f())
let q := sload(g())
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// {
// x_1 := add(x_1, 1)
// sstore(0x00, 0x00)
// }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let t := extcodesize(f())
// let q := sload(g())
// }
// }

29
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_state_loop.yul Normal file
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@ -0,0 +1,29 @@
{
function f() -> x { x := g() }
function g() -> x { for {} 1 {} {} }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := extcodesize(f())
let q := g()
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// {
// for { } 1 { }
// { }
// }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let t := extcodesize(f())
// let q := g()
// }
// }

26
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_state_recursive_function.yul Normal file
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@ -0,0 +1,26 @@
{
function f() -> x { x := g() }
function g() -> x { x := g() }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := extcodesize(f())
let q := sload(g())
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// { x_1 := g() }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// let t := extcodesize(f())
// let q := sload(g())
// }
// }

32
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_staticall_returndatasize.yul Normal file
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@ -0,0 +1,32 @@
{
let b := 1
// invalidates state in post
for { let a := 1 } iszero(eq(a, 10)) {pop(call(2, 0x01, 2, 0x00, 32, 0x010, 32))} {
let inv := add(b, 42)
let x := returndatasize()
a := add(x, 1)
pop(staticcall(2, 3, 0, 32, 64, 32)) // prevents moving returndatasize
mstore(a, inv)
}
}
// ====
// EVMVersion: >=byzantium
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// for { }
// iszero(eq(a, 10))
// {
// pop(call(2, 0x01, 2, 0x00, 32, 0x010, 32))
// }
// {
// let x := returndatasize()
// a := add(x, 1)
// pop(staticcall(2, 3, 0, 32, 64, 32))
// mstore(a, inv)
// }
// }

57
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_storage.yul Normal file
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@ -0,0 +1,57 @@
{
let b := 1
// invalidates storage in post
for { let a := 1 } iszero(eq(a, 10)) { sstore(0x00, 0x01)} {
let inv := add(b, 42)
let x := sload(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
// invalidates storage in body
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := sload(mul(inv, 3))
a := add(x, 1)
sstore(a, inv)
}
// invalidates state in body
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
pop(callcode(100, 0x010, 10, 0x00, 32, 0x0100, 32))
let x := sload(mul(inv, 3))
a := add(x, 1)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// for { } iszero(eq(a, 10)) { sstore(0x00, 0x01) }
// {
// let x := sload(mul(inv, 3))
// a := add(x, 1)
// mstore(a, inv)
// }
// let a_1 := 1
// let inv_2 := add(b, 42)
// for { } iszero(eq(a_1, 10)) { a_1 := add(a_1, 1) }
// {
// let x_3 := sload(mul(inv_2, 3))
// a_1 := add(x_3, 1)
// sstore(a_1, inv_2)
// }
// let a_4 := 1
// let inv_5 := add(b, 42)
// for { } iszero(eq(a_4, 10)) { a_4 := add(a_4, 1) }
// {
// pop(callcode(100, 0x010, 10, 0x00, 32, 0x0100, 32))
// let x_6 := sload(mul(inv_5, 3))
// a_4 := add(x_6, 1)
// }
// }

28
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_storage_function.yul Normal file
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@ -0,0 +1,28 @@
{
function f() -> x { x := g() }
function g() -> x {
x := add(x, 1)
sstore(0x00, 0x00)
}
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let q := sload(g())
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// {
// x_1 := add(x_1, 1)
// sstore(0x00, 0x00)
// }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { let q := sload(g()) }
// }

25
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/no_move_storage_loop.yul Normal file
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@ -0,0 +1,25 @@
{
function f() -> x { x := g() }
function g() -> x { for {} 1 {} {} }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let t := sload(f())
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function f() -> x
// { x := g() }
// function g() -> x_1
// {
// for { } 1 { }
// { }
// }
// let b := 1
// let a := 1
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { let t := sload(f()) }
// }

21
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/not_first.yul Normal file
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@ -0,0 +1,21 @@
{
function g() -> x { x := add(mload(x), 1) }
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
sstore(0, a)
let q := keccak256(g(), 32)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// function g() -> x
// { x := add(mload(x), 1) }
// let b := 1
// let a := 1
// let q := keccak256(g(), 32)
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// { sstore(0, a) }
// }

25
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/simple_memory.yul Normal file
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@ -0,0 +1,25 @@
{
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := mload(mul(inv, 3))
let y := keccak256(mul(b, 13), 32)
a := add(x, 1)
sstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// let x := mload(mul(inv, 3))
// let y := keccak256(mul(b, 13), 32)
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// a := add(x, 1)
// sstore(a, inv)
// }
// }

23
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/simple_state.yul Normal file
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@ -0,0 +1,23 @@
{
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := extcodesize(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// let x := extcodesize(mul(inv, 3))
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// a := add(x, 1)
// mstore(a, inv)
// }
// }

23
test/libyul/yulOptimizerTests/loopInvariantCodeMotion/simple_storage.yul Normal file
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@ -0,0 +1,23 @@
{
let b := 1
for { let a := 1 } iszero(eq(a, 10)) { a := add(a, 1) } {
let inv := add(b, 42)
let x := sload(mul(inv, 3))
a := add(x, 1)
mstore(a, inv)
}
}
// ----
// step: loopInvariantCodeMotion
//
// {
// let b := 1
// let a := 1
// let inv := add(b, 42)
// let x := sload(mul(inv, 3))
// for { } iszero(eq(a, 10)) { a := add(a, 1) }
// {
// a := add(x, 1)
// mstore(a, inv)
// }
// }