solidity/test/libevmasm/Optimiser.cpp
2021-04-26 19:56:44 +02:00

1754 lines
38 KiB
C++

/*
This file is part of solidity.
solidity is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
solidity is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with solidity. If not, see <http://www.gnu.org/licenses/>.
*/
// SPDX-License-Identifier: GPL-3.0
/**
* @author Christian <c@ethdev.com>
* @date 2014
* Tests for the Solidity optimizer.
*/
#include <test/Common.h>
#include <libevmasm/CommonSubexpressionEliminator.h>
#include <libevmasm/PeepholeOptimiser.h>
#include <libevmasm/Inliner.h>
#include <libevmasm/JumpdestRemover.h>
#include <libevmasm/ControlFlowGraph.h>
#include <libevmasm/BlockDeduplicator.h>
#include <libevmasm/Assembly.h>
#include <boost/test/unit_test.hpp>
#include <range/v3/algorithm/any_of.hpp>
#include <string>
#include <tuple>
#include <memory>
using namespace std;
using namespace solidity::langutil;
using namespace solidity::evmasm;
namespace solidity::frontend::test
{
namespace
{
AssemblyItems addDummyLocations(AssemblyItems const& _input)
{
// add dummy locations to each item so that we can check that they are not deleted
AssemblyItems input = _input;
for (AssemblyItem& item: input)
item.setLocation({1, 3, nullptr});
return input;
}
evmasm::KnownState createInitialState(AssemblyItems const& _input)
{
evmasm::KnownState state;
for (auto const& item: addDummyLocations(_input))
state.feedItem(item, true);
return state;
}
AssemblyItems CSE(AssemblyItems const& _input, evmasm::KnownState const& _state = evmasm::KnownState())
{
AssemblyItems input = addDummyLocations(_input);
bool usesMsize = ranges::any_of(_input, [](AssemblyItem const& _i) {
return _i == AssemblyItem{Instruction::MSIZE} || _i.type() == VerbatimBytecode;
});
evmasm::CommonSubexpressionEliminator cse(_state);
BOOST_REQUIRE(cse.feedItems(input.begin(), input.end(), usesMsize) == input.end());
AssemblyItems output = cse.getOptimizedItems();
for (AssemblyItem const& item: output)
{
BOOST_CHECK(item == Instruction::POP || item.location().isValid());
}
return output;
}
void checkCSE(
AssemblyItems const& _input,
AssemblyItems const& _expectation,
KnownState const& _state = evmasm::KnownState()
)
{
AssemblyItems output = CSE(_input, _state);
BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end());
}
AssemblyItems CFG(AssemblyItems const& _input)
{
AssemblyItems output = _input;
// Running it four times should be enough for these tests.
for (unsigned i = 0; i < 4; ++i)
{
ControlFlowGraph cfg(output);
AssemblyItems optItems;
for (BasicBlock const& block: cfg.optimisedBlocks())
copy(output.begin() + block.begin, output.begin() + block.end,
back_inserter(optItems));
output = move(optItems);
}
return output;
}
void checkCFG(AssemblyItems const& _input, AssemblyItems const& _expectation)
{
AssemblyItems output = CFG(_input);
BOOST_CHECK_EQUAL_COLLECTIONS(_expectation.begin(), _expectation.end(), output.begin(), output.end());
}
}
BOOST_AUTO_TEST_SUITE(Optimiser)
BOOST_AUTO_TEST_CASE(cse_push_immutable_same)
{
AssemblyItem pushImmutable{PushImmutable, 0x1234};
checkCSE({pushImmutable, pushImmutable}, {pushImmutable, Instruction::DUP1});
}
BOOST_AUTO_TEST_CASE(cse_push_immutable_different)
{
AssemblyItems input{{PushImmutable, 0x1234},{PushImmutable, 0xABCD}};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_assign_immutable)
{
{
AssemblyItems input{u256(0x42), {AssignImmutable, 0x1234}};
checkCSE(input, input);
}
{
AssemblyItems input{{AssignImmutable, 0x1234}};
checkCSE(input, input);
}
}
BOOST_AUTO_TEST_CASE(cse_assign_immutable_breaks)
{
AssemblyItems input = addDummyLocations(AssemblyItems{
u256(0x42),
{AssignImmutable, 0x1234},
Instruction::ORIGIN
});
evmasm::CommonSubexpressionEliminator cse{evmasm::KnownState()};
// Make sure CSE breaks after AssignImmutable.
BOOST_REQUIRE(cse.feedItems(input.begin(), input.end(), false) == input.begin() + 2);
}
BOOST_AUTO_TEST_CASE(cse_intermediate_swap)
{
evmasm::KnownState state;
evmasm::CommonSubexpressionEliminator cse(state);
AssemblyItems input{
Instruction::SWAP1, Instruction::POP, Instruction::ADD, u256(0), Instruction::SWAP1,
Instruction::SLOAD, Instruction::SWAP1, u256(100), Instruction::EXP, Instruction::SWAP1,
Instruction::DIV, u256(0xff), Instruction::AND
};
BOOST_REQUIRE(cse.feedItems(input.begin(), input.end(), false) == input.end());
AssemblyItems output = cse.getOptimizedItems();
BOOST_CHECK(!output.empty());
}
BOOST_AUTO_TEST_CASE(cse_negative_stack_access)
{
AssemblyItems input{Instruction::DUP2, u256(0)};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_negative_stack_end)
{
AssemblyItems input{Instruction::ADD};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_intermediate_negative_stack)
{
AssemblyItems input{Instruction::ADD, u256(1), Instruction::DUP1};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_pop)
{
checkCSE({Instruction::POP}, {Instruction::POP});
}
BOOST_AUTO_TEST_CASE(cse_unneeded_items)
{
AssemblyItems input{
Instruction::ADD,
Instruction::SWAP1,
Instruction::POP,
u256(7),
u256(8),
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_constant_addition)
{
AssemblyItems input{u256(7), u256(8), Instruction::ADD};
checkCSE(input, {u256(7 + 8)});
}
BOOST_AUTO_TEST_CASE(cse_invariants)
{
AssemblyItems input{
Instruction::DUP1,
Instruction::DUP1,
u256(0),
Instruction::OR,
Instruction::OR
};
checkCSE(input, {Instruction::DUP1});
}
BOOST_AUTO_TEST_CASE(cse_subself)
{
checkCSE({Instruction::DUP1, Instruction::SUB}, {Instruction::POP, u256(0)});
}
BOOST_AUTO_TEST_CASE(cse_subother)
{
checkCSE({Instruction::SUB}, {Instruction::SUB});
}
BOOST_AUTO_TEST_CASE(cse_double_negation)
{
checkCSE({Instruction::DUP5, Instruction::NOT, Instruction::NOT}, {Instruction::DUP5});
}
BOOST_AUTO_TEST_CASE(cse_double_iszero)
{
checkCSE({Instruction::GT, Instruction::ISZERO, Instruction::ISZERO}, {Instruction::GT});
checkCSE({Instruction::GT, Instruction::ISZERO}, {Instruction::GT, Instruction::ISZERO});
checkCSE(
{Instruction::ISZERO, Instruction::ISZERO, Instruction::ISZERO},
{Instruction::ISZERO}
);
}
BOOST_AUTO_TEST_CASE(cse_associativity)
{
AssemblyItems input{
Instruction::DUP1,
Instruction::DUP1,
u256(0),
Instruction::OR,
Instruction::OR
};
checkCSE(input, {Instruction::DUP1});
}
BOOST_AUTO_TEST_CASE(cse_associativity2)
{
AssemblyItems input{
u256(0),
Instruction::DUP2,
u256(2),
u256(1),
Instruction::DUP6,
Instruction::ADD,
u256(2),
Instruction::ADD,
Instruction::ADD,
Instruction::ADD,
Instruction::ADD
};
checkCSE(input, {Instruction::DUP2, Instruction::DUP2, Instruction::ADD, u256(5), Instruction::ADD});
}
BOOST_AUTO_TEST_CASE(cse_double_shift_right_overflow)
{
if (solidity::test::CommonOptions::get().evmVersion().hasBitwiseShifting())
{
AssemblyItems input{
Instruction::CALLVALUE,
u256(2),
Instruction::SHR,
u256(-1),
Instruction::SHR
};
checkCSE(input, {u256(0)});
}
}
BOOST_AUTO_TEST_CASE(cse_double_shift_left_overflow)
{
if (solidity::test::CommonOptions::get().evmVersion().hasBitwiseShifting())
{
AssemblyItems input{
Instruction::DUP1,
u256(2),
Instruction::SHL,
u256(-1),
Instruction::SHL
};
checkCSE(input, {u256(0)});
}
}
BOOST_AUTO_TEST_CASE(cse_byte_ordering_bug)
{
AssemblyItems input{
u256(31),
Instruction::CALLVALUE,
Instruction::BYTE
};
checkCSE(input, {u256(31), Instruction::CALLVALUE, Instruction::BYTE});
}
BOOST_AUTO_TEST_CASE(cse_byte_ordering_fix)
{
AssemblyItems input{
Instruction::CALLVALUE,
u256(31),
Instruction::BYTE
};
checkCSE(input, {u256(0xff), Instruction::CALLVALUE, Instruction::AND});
}
BOOST_AUTO_TEST_CASE(cse_storage)
{
AssemblyItems input{
u256(0),
Instruction::SLOAD,
u256(0),
Instruction::SLOAD,
Instruction::ADD,
u256(0),
Instruction::SSTORE
};
checkCSE(input, {
u256(0),
Instruction::DUP1,
Instruction::SLOAD,
Instruction::DUP1,
Instruction::ADD,
Instruction::SWAP1,
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_noninterleaved_storage)
{
// two stores to the same location should be replaced by only one store, even if we
// read in the meantime
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE,
Instruction::DUP1,
Instruction::SLOAD,
u256(8),
Instruction::DUP3,
Instruction::SSTORE
};
checkCSE(input, {
u256(8),
Instruction::DUP2,
Instruction::SSTORE,
u256(7)
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage)
{
// stores and reads to/from two unknown locations, should not optimize away the first store
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE, // store to "DUP1"
Instruction::DUP2,
Instruction::SLOAD, // read from "DUP2", might be equal to "DUP1"
u256(0),
Instruction::DUP3,
Instruction::SSTORE // store different value to "DUP1"
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_same_value)
{
// stores and reads to/from two unknown locations, should not optimize away the first store
// but it should optimize away the second, since we already know the value will be the same
AssemblyItems input{
u256(7),
Instruction::DUP2,
Instruction::SSTORE, // store to "DUP1"
Instruction::DUP2,
Instruction::SLOAD, // read from "DUP2", might be equal to "DUP1"
u256(6),
u256(1),
Instruction::ADD,
Instruction::DUP3,
Instruction::SSTORE // store same value to "DUP1"
};
checkCSE(input, {
u256(7),
Instruction::DUP2,
Instruction::SSTORE,
Instruction::DUP2,
Instruction::SLOAD
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_at_known_location)
{
// stores and reads to/from two known locations, should optimize away the first store,
// because we know that the location is different
AssemblyItems input{
u256(0x70),
u256(1),
Instruction::SSTORE, // store to 1
u256(2),
Instruction::SLOAD, // read from 2, is different from 1
u256(0x90),
u256(1),
Instruction::SSTORE // store different value at 1
};
checkCSE(input, {
u256(2),
Instruction::SLOAD,
u256(0x90),
u256(1),
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_interleaved_storage_at_known_location_offset)
{
// stores and reads to/from two locations which are known to be different,
// should optimize away the first store, because we know that the location is different
AssemblyItems input{
u256(0x70),
Instruction::DUP2,
u256(1),
Instruction::ADD,
Instruction::SSTORE, // store to "DUP1"+1
Instruction::DUP1,
u256(2),
Instruction::ADD,
Instruction::SLOAD, // read from "DUP1"+2, is different from "DUP1"+1
u256(0x90),
Instruction::DUP3,
u256(1),
Instruction::ADD,
Instruction::SSTORE // store different value at "DUP1"+1
};
checkCSE(input, {
u256(2),
Instruction::DUP2,
Instruction::ADD,
Instruction::SLOAD,
u256(0x90),
u256(1),
Instruction::DUP4,
Instruction::ADD,
Instruction::SSTORE
});
}
BOOST_AUTO_TEST_CASE(cse_deep_stack)
{
AssemblyItems input{
Instruction::ADD,
Instruction::SWAP1,
Instruction::POP,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP8,
Instruction::SWAP5,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
};
checkCSE(input, {
Instruction::SWAP4,
Instruction::SWAP12,
Instruction::SWAP3,
Instruction::SWAP11,
Instruction::POP,
Instruction::SWAP1,
Instruction::SWAP3,
Instruction::ADD,
Instruction::SWAP8,
Instruction::POP,
Instruction::SWAP6,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
Instruction::POP,
});
}
BOOST_AUTO_TEST_CASE(cse_jumpi_no_jump)
{
AssemblyItems input{
u256(0),
u256(1),
Instruction::DUP2,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
checkCSE(input, {
u256(0),
u256(1)
});
}
BOOST_AUTO_TEST_CASE(cse_jumpi_jump)
{
AssemblyItems input{
u256(1),
u256(1),
Instruction::DUP2,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
checkCSE(input, {
u256(1),
Instruction::DUP1,
AssemblyItem(PushTag, 1),
Instruction::JUMP
});
}
BOOST_AUTO_TEST_CASE(cse_empty_keccak256)
{
AssemblyItems input{
u256(0),
Instruction::DUP2,
Instruction::KECCAK256
};
checkCSE(input, {
u256(util::keccak256(bytesConstRef()))
});
}
BOOST_AUTO_TEST_CASE(cse_partial_keccak256)
{
AssemblyItems input{
u256(0xabcd) << (256 - 16),
u256(0),
Instruction::MSTORE,
u256(2),
u256(0),
Instruction::KECCAK256
};
checkCSE(input, {
u256(0xabcd) << (256 - 16),
u256(0),
Instruction::MSTORE,
u256(util::keccak256(bytes{0xab, 0xcd}))
});
}
BOOST_AUTO_TEST_CASE(cse_keccak256_twice_same_location)
{
// Keccak-256 twice from same dynamic location
AssemblyItems input{
Instruction::DUP2,
Instruction::DUP1,
Instruction::MSTORE,
u256(64),
Instruction::DUP2,
Instruction::KECCAK256,
u256(64),
Instruction::DUP3,
Instruction::KECCAK256
};
checkCSE(input, {
Instruction::DUP2,
Instruction::DUP1,
Instruction::MSTORE,
u256(64),
Instruction::DUP2,
Instruction::KECCAK256,
Instruction::DUP1
});
}
BOOST_AUTO_TEST_CASE(cse_keccak256_twice_same_content)
{
// Keccak-256 twice from different dynamic location but with same content
AssemblyItems input{
Instruction::DUP1,
u256(0x80),
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
u256(0x80),
Instruction::KECCAK256, // keccak256(m[128..(128+32)])
Instruction::DUP2,
u256(12),
Instruction::MSTORE, // m[12] = DUP1
u256(0x20),
u256(12),
Instruction::KECCAK256 // keccak256(m[12..(12+32)])
};
checkCSE(input, {
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE,
u256(0x20),
Instruction::SWAP1,
Instruction::KECCAK256,
u256(12),
Instruction::DUP3,
Instruction::SWAP1,
Instruction::MSTORE,
Instruction::DUP1
});
}
BOOST_AUTO_TEST_CASE(cse_keccak256_twice_same_content_dynamic_store_in_between)
{
// Keccak-256 twice from different dynamic location but with same content,
// dynamic mstore in between, which forces us to re-calculate the hash
AssemblyItems input{
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
Instruction::DUP1,
Instruction::DUP3,
Instruction::KECCAK256, // keccak256(m[128..(128+32)])
u256(12),
Instruction::DUP5,
Instruction::DUP2,
Instruction::MSTORE, // m[12] = DUP1
Instruction::DUP12,
Instruction::DUP14,
Instruction::MSTORE, // destroys memory knowledge
Instruction::SWAP2,
Instruction::SWAP1,
Instruction::SWAP2,
Instruction::KECCAK256 // keccak256(m[12..(12+32)])
};
checkCSE(input, input);
}
BOOST_AUTO_TEST_CASE(cse_keccak256_twice_same_content_noninterfering_store_in_between)
{
// Keccak-256 twice from different dynamic location but with same content,
// dynamic mstore in between, but does not force us to re-calculate the hash
AssemblyItems input{
u256(0x80),
Instruction::DUP2,
Instruction::DUP2,
Instruction::MSTORE, // m[128] = DUP1
u256(0x20),
Instruction::DUP1,
Instruction::DUP3,
Instruction::KECCAK256, // keccak256(m[128..(128+32)])
u256(12),
Instruction::DUP5,
Instruction::DUP2,
Instruction::MSTORE, // m[12] = DUP1
Instruction::DUP12,
u256(12 + 32),
Instruction::MSTORE, // does not destoy memory knowledge
Instruction::DUP13,
u256(128 - 32),
Instruction::MSTORE, // does not destoy memory knowledge
u256(0x20),
u256(12),
Instruction::KECCAK256 // keccak256(m[12..(12+32)])
};
// if this changes too often, only count the number of SHA3 and MSTORE instructions
AssemblyItems output = CSE(input);
BOOST_CHECK_EQUAL(4, count(output.begin(), output.end(), AssemblyItem(Instruction::MSTORE)));
BOOST_CHECK_EQUAL(1, count(output.begin(), output.end(), AssemblyItem(Instruction::KECCAK256)));
}
BOOST_AUTO_TEST_CASE(cse_with_initially_known_stack)
{
evmasm::KnownState state = createInitialState(AssemblyItems{
u256(0x12),
u256(0x20),
Instruction::ADD
});
AssemblyItems input{
u256(0x12 + 0x20)
};
checkCSE(input, AssemblyItems{Instruction::DUP1}, state);
}
BOOST_AUTO_TEST_CASE(cse_equality_on_initially_known_stack)
{
evmasm::KnownState state = createInitialState(AssemblyItems{Instruction::DUP1});
AssemblyItems input{
Instruction::EQ
};
AssemblyItems output = CSE(input, state);
// check that it directly pushes 1 (true)
BOOST_CHECK(find(output.begin(), output.end(), AssemblyItem(u256(1))) != output.end());
}
BOOST_AUTO_TEST_CASE(cse_access_previous_sequence)
{
// Tests that the code generator detects whether it tries to access SLOAD instructions
// from a sequenced expression which is not in its scope.
evmasm::KnownState state = createInitialState(AssemblyItems{
u256(0),
Instruction::SLOAD,
u256(1),
Instruction::ADD,
u256(0),
Instruction::SSTORE
});
// now stored: val_1 + 1 (value at sequence 1)
// if in the following instructions, the SLOAD cresolves to "val_1 + 1",
// this cannot be generated because we cannot load from sequence 1 anymore.
AssemblyItems input{
u256(0),
Instruction::SLOAD,
};
BOOST_CHECK_THROW(CSE(input, state), StackTooDeepException);
// @todo for now, this throws an exception, but it should recover to the following
// (or an even better version) at some point:
// 0, SLOAD, 1, ADD, SSTORE, 0 SLOAD
}
BOOST_AUTO_TEST_CASE(cse_optimise_return)
{
checkCSE(
AssemblyItems{u256(0), u256(7), Instruction::RETURN},
AssemblyItems{Instruction::STOP}
);
}
BOOST_AUTO_TEST_CASE(control_flow_graph_remove_unused)
{
// remove parts of the code that are unused
AssemblyItems input{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
u256(7),
AssemblyItem(Tag, 1),
};
checkCFG(input, {});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_remove_unused_loop)
{
AssemblyItems input{
AssemblyItem(PushTag, 3),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(7),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(8),
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 3),
u256(11)
};
checkCFG(input, {u256(11)});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_reconnect_single_jump_source)
{
// move code that has only one unconditional jump source
AssemblyItems input{
u256(1),
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(2),
AssemblyItem(PushTag, 3),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(3),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 3),
u256(4),
};
checkCFG(input, {u256(1), u256(3), u256(2), u256(4)});
}
BOOST_AUTO_TEST_CASE(control_flow_graph_do_not_remove_returned_to)
{
// do not remove parts that are "returned to"
AssemblyItems input{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(2)
};
checkCFG(input, {u256(2)});
}
BOOST_AUTO_TEST_CASE(block_deduplicator)
{
AssemblyItems input{
AssemblyItem(PushTag, 2),
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 3),
u256(6),
Instruction::SWAP3,
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(6),
Instruction::SWAP3,
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(6),
Instruction::SWAP3,
Instruction::JUMP,
AssemblyItem(Tag, 3)
};
BlockDeduplicator deduplicator(input);
deduplicator.deduplicate();
set<u256> pushTags;
for (AssemblyItem const& item: input)
if (item.type() == PushTag)
pushTags.insert(item.data());
BOOST_CHECK_EQUAL(pushTags.size(), 2);
}
BOOST_AUTO_TEST_CASE(block_deduplicator_assign_immutable_same)
{
AssemblyItems blocks{
AssemblyItem(Tag, 1),
u256(42),
AssemblyItem{AssignImmutable, 0x1234},
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(42),
AssemblyItem{AssignImmutable, 0x1234},
Instruction::JUMP
};
AssemblyItems input = AssemblyItems{
AssemblyItem(PushTag, 2),
AssemblyItem(PushTag, 1),
} + blocks;
AssemblyItems output = AssemblyItems{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 1),
} + blocks;
BlockDeduplicator deduplicator(input);
deduplicator.deduplicate();
BOOST_CHECK_EQUAL_COLLECTIONS(input.begin(), input.end(), output.begin(), output.end());
}
BOOST_AUTO_TEST_CASE(block_deduplicator_assign_immutable_different_value)
{
AssemblyItems input{
AssemblyItem(PushTag, 2),
AssemblyItem(PushTag, 1),
AssemblyItem(Tag, 1),
u256(42),
AssemblyItem{AssignImmutable, 0x1234},
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(23),
AssemblyItem{AssignImmutable, 0x1234},
Instruction::JUMP
};
BlockDeduplicator deduplicator(input);
BOOST_CHECK(!deduplicator.deduplicate());
}
BOOST_AUTO_TEST_CASE(block_deduplicator_assign_immutable_different_hash)
{
AssemblyItems input{
AssemblyItem(PushTag, 2),
AssemblyItem(PushTag, 1),
AssemblyItem(Tag, 1),
u256(42),
AssemblyItem{AssignImmutable, 0x1234},
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(42),
AssemblyItem{AssignImmutable, 0xABCD},
Instruction::JUMP
};
BlockDeduplicator deduplicator(input);
BOOST_CHECK(!deduplicator.deduplicate());
}
BOOST_AUTO_TEST_CASE(block_deduplicator_loops)
{
AssemblyItems input{
u256(0),
Instruction::SLOAD,
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
Instruction::JUMPI,
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(5),
u256(6),
Instruction::SSTORE,
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(5),
u256(6),
Instruction::SSTORE,
AssemblyItem(PushTag, 2),
Instruction::JUMP,
};
BlockDeduplicator deduplicator(input);
deduplicator.deduplicate();
set<u256> pushTags;
for (AssemblyItem const& item: input)
if (item.type() == PushTag)
pushTags.insert(item.data());
BOOST_CHECK_EQUAL(pushTags.size(), 1);
}
BOOST_AUTO_TEST_CASE(clear_unreachable_code)
{
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
u256(0),
Instruction::SLOAD,
AssemblyItem(Tag, 2),
u256(5),
u256(6),
Instruction::SSTORE,
AssemblyItem(PushTag, 1),
Instruction::JUMP,
u256(5),
u256(6)
};
AssemblyItems expectation{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 2),
u256(5),
u256(6),
Instruction::SSTORE,
AssemblyItem(PushTag, 1),
Instruction::JUMP
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(peephole_double_push)
{
AssemblyItems items{
u256(0),
u256(0),
u256(5),
u256(5),
u256(4),
u256(5)
};
AssemblyItems expectation{
u256(0),
Instruction::DUP1,
u256(5),
Instruction::DUP1,
u256(4),
u256(5)
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(peephole_pop_calldatasize)
{
AssemblyItems items{
u256(4),
Instruction::CALLDATASIZE,
Instruction::LT,
Instruction::POP
};
PeepholeOptimiser peepOpt(items);
for (size_t i = 0; i < 3; i++)
BOOST_CHECK(peepOpt.optimise());
BOOST_CHECK(items.empty());
}
BOOST_AUTO_TEST_CASE(peephole_commutative_swap1)
{
vector<Instruction> ops{
Instruction::ADD,
Instruction::MUL,
Instruction::EQ,
Instruction::AND,
Instruction::OR,
Instruction::XOR
};
for (Instruction const op: ops)
{
AssemblyItems items{
u256(1),
u256(2),
Instruction::SWAP1,
op,
u256(4),
u256(5)
};
AssemblyItems expectation{
u256(1),
u256(2),
op,
u256(4),
u256(5)
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
}
BOOST_AUTO_TEST_CASE(peephole_noncommutative_swap1)
{
// NOTE: not comprehensive
vector<Instruction> ops{
Instruction::SUB,
Instruction::DIV,
Instruction::SDIV,
Instruction::MOD,
Instruction::SMOD,
Instruction::EXP
};
for (Instruction const op: ops)
{
AssemblyItems items{
u256(1),
u256(2),
Instruction::SWAP1,
op,
u256(4),
u256(5)
};
AssemblyItems expectation{
u256(1),
u256(2),
Instruction::SWAP1,
op,
u256(4),
u256(5)
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(!peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
}
BOOST_AUTO_TEST_CASE(peephole_swap_comparison)
{
map<Instruction, Instruction> swappableOps{
{ Instruction::LT, Instruction::GT },
{ Instruction::GT, Instruction::LT },
{ Instruction::SLT, Instruction::SGT },
{ Instruction::SGT, Instruction::SLT }
};
for (auto const& op: swappableOps)
{
AssemblyItems items{
u256(1),
u256(2),
Instruction::SWAP1,
op.first,
u256(4),
u256(5)
};
AssemblyItems expectation{
u256(1),
u256(2),
op.second,
u256(4),
u256(5)
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
}
BOOST_AUTO_TEST_CASE(peephole_truthy_and)
{
AssemblyItems items{
AssemblyItem(Tag, 1),
Instruction::BALANCE,
u256(0),
Instruction::NOT,
Instruction::AND,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
AssemblyItems expectation{
AssemblyItem(Tag, 1),
Instruction::BALANCE,
AssemblyItem(PushTag, 1),
Instruction::JUMPI
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(peephole_iszero_iszero_jumpi)
{
AssemblyItems items{
AssemblyItem(Tag, 1),
u256(0),
Instruction::CALLDATALOAD,
Instruction::ISZERO,
Instruction::ISZERO,
AssemblyItem(PushTag, 1),
Instruction::JUMPI,
u256(0),
u256(0x20),
Instruction::RETURN
};
AssemblyItems expectation{
AssemblyItem(Tag, 1),
u256(0),
Instruction::CALLDATALOAD,
AssemblyItem(PushTag, 1),
Instruction::JUMPI,
u256(0),
u256(0x20),
Instruction::RETURN
};
PeepholeOptimiser peepOpt(items);
BOOST_REQUIRE(peepOpt.optimise());
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(jumpdest_removal)
{
AssemblyItems items{
AssemblyItem(Tag, 2),
AssemblyItem(PushTag, 1),
u256(5),
AssemblyItem(Tag, 10),
AssemblyItem(Tag, 3),
u256(6),
AssemblyItem(Tag, 1),
Instruction::JUMP,
};
AssemblyItems expectation{
AssemblyItem(PushTag, 1),
u256(5),
u256(6),
AssemblyItem(Tag, 1),
Instruction::JUMP
};
JumpdestRemover jdr(items);
BOOST_REQUIRE(jdr.optimise({}));
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(jumpdest_removal_subassemblies)
{
// This tests that tags from subassemblies are not removed
// if they are referenced by a super-assembly. Furthermore,
// tag unifications (due to block deduplication) is also
// visible at the super-assembly.
Assembly main;
AssemblyPointer sub = make_shared<Assembly>();
sub->append(u256(1));
auto t1 = sub->newTag();
sub->append(t1);
sub->append(u256(2));
sub->append(Instruction::JUMP);
auto t2 = sub->newTag();
sub->append(t2); // Identical to T1, will be unified
sub->append(u256(2));
sub->append(Instruction::JUMP);
auto t3 = sub->newTag();
sub->append(t3);
auto t4 = sub->newTag();
sub->append(t4);
auto t5 = sub->newTag();
sub->append(t5); // This will be removed
sub->append(u256(7));
sub->append(t4.pushTag());
sub->append(Instruction::JUMP);
size_t subId = static_cast<size_t>(main.appendSubroutine(sub).data());
main.append(t1.toSubAssemblyTag(subId));
main.append(t1.toSubAssemblyTag(subId));
main.append(u256(8));
Assembly::OptimiserSettings settings;
settings.isCreation = false;
settings.runInliner = false;
settings.runJumpdestRemover = true;
settings.runPeephole = true;
settings.runDeduplicate = true;
settings.runCSE = true;
settings.runConstantOptimiser = true;
settings.evmVersion = solidity::test::CommonOptions::get().evmVersion();
settings.expectedExecutionsPerDeployment = 200;
main.optimise(settings);
AssemblyItems expectationMain{
AssemblyItem(PushSubSize, 0),
t1.toSubAssemblyTag(subId).pushTag(),
t1.toSubAssemblyTag(subId).pushTag(),
u256(8)
};
BOOST_CHECK_EQUAL_COLLECTIONS(
main.items().begin(), main.items().end(),
expectationMain.begin(), expectationMain.end()
);
AssemblyItems expectationSub{
u256(1), t1.tag(), u256(2), Instruction::JUMP, t4.tag(), u256(7), t4.pushTag(), Instruction::JUMP
};
BOOST_CHECK_EQUAL_COLLECTIONS(
sub->items().begin(), sub->items().end(),
expectationSub.begin(), expectationSub.end()
);
}
BOOST_AUTO_TEST_CASE(cse_sub_zero)
{
checkCSE({
u256(0),
Instruction::DUP2,
Instruction::SUB
}, {
Instruction::DUP1
});
checkCSE({
Instruction::DUP1,
u256(0),
Instruction::SUB
}, {
u256(0),
Instruction::DUP2,
Instruction::SWAP1,
Instruction::SUB
});
}
BOOST_AUTO_TEST_CASE(cse_remove_redundant_shift_masking)
{
if (!solidity::test::CommonOptions::get().evmVersion().hasBitwiseShifting())
return;
for (unsigned i = 1; i < 256; i++)
{
checkCSE({
u256(boost::multiprecision::pow(u256(2), i) - 1),
Instruction::CALLVALUE,
u256(256-i),
Instruction::SHR,
Instruction::AND
}, {
Instruction::CALLVALUE,
u256(256-i),
Instruction::SHR,
});
checkCSE({
Instruction::CALLVALUE,
u256(256-i),
Instruction::SHR,
u256(boost::multiprecision::pow(u256(2), i)-1),
Instruction::AND
}, {
Instruction::CALLVALUE,
u256(256-i),
Instruction::SHR,
});
}
// Check that opt. does NOT trigger
for (unsigned i = 1; i < 255; i++)
{
checkCSE({
u256(boost::multiprecision::pow(u256(2), i) - 1),
Instruction::CALLVALUE,
u256(255-i),
Instruction::SHR,
Instruction::AND
}, { // Opt. did some reordering
Instruction::CALLVALUE,
u256(255-i),
Instruction::SHR,
u256(boost::multiprecision::pow(u256(2), i)-1),
Instruction::AND
});
checkCSE({
Instruction::CALLVALUE,
u256(255-i),
Instruction::SHR,
u256(boost::multiprecision::pow(u256(2), i)-1),
Instruction::AND
}, { // Opt. did some reordering
u256(boost::multiprecision::pow(u256(2), i)-1),
Instruction::CALLVALUE,
u256(255-i),
Instruction::SHR,
Instruction::AND
});
}
//(x >> (31*8)) & 0xffffffff
checkCSE({
Instruction::CALLVALUE,
u256(31*8),
Instruction::SHR,
u256(0xffffffff),
Instruction::AND
}, {
Instruction::CALLVALUE,
u256(31*8),
Instruction::SHR
});
}
BOOST_AUTO_TEST_CASE(cse_remove_unwanted_masking_of_address)
{
vector<Instruction> ops{
Instruction::ADDRESS,
Instruction::CALLER,
Instruction::ORIGIN,
Instruction::COINBASE
};
for (auto const& op: ops)
{
checkCSE({
u256("0xffffffffffffffffffffffffffffffffffffffff"),
op,
Instruction::AND
}, {
op
});
checkCSE({
op,
u256("0xffffffffffffffffffffffffffffffffffffffff"),
Instruction::AND
}, {
op
});
// do not remove mask for other masking
checkCSE({
u256(1234),
op,
Instruction::AND
}, {
op,
u256(1234),
Instruction::AND
});
checkCSE({
op,
u256(1234),
Instruction::AND
}, {
u256(1234),
op,
Instruction::AND
});
}
// leave other opcodes untouched
checkCSE({
u256("0xffffffffffffffffffffffffffffffffffffffff"),
Instruction::CALLVALUE,
Instruction::AND
}, {
Instruction::CALLVALUE,
u256("0xffffffffffffffffffffffffffffffffffffffff"),
Instruction::AND
});
checkCSE({
Instruction::CALLVALUE,
u256("0xffffffffffffffffffffffffffffffffffffffff"),
Instruction::AND
}, {
u256("0xffffffffffffffffffffffffffffffffffffffff"),
Instruction::CALLVALUE,
Instruction::AND
});
}
BOOST_AUTO_TEST_CASE(cse_replace_too_large_shift)
{
if (!solidity::test::CommonOptions::get().evmVersion().hasBitwiseShifting())
return;
checkCSE({
Instruction::CALLVALUE,
u256(299),
Instruction::SHL
}, {
u256(0)
});
checkCSE({
Instruction::CALLVALUE,
u256(299),
Instruction::SHR
}, {
u256(0)
});
checkCSE({
Instruction::CALLVALUE,
u256(255),
Instruction::SHL
}, {
Instruction::CALLVALUE,
u256(255),
Instruction::SHL
});
checkCSE({
Instruction::CALLVALUE,
u256(255),
Instruction::SHR
}, {
Instruction::CALLVALUE,
u256(255),
Instruction::SHR
});
}
BOOST_AUTO_TEST_CASE(inliner)
{
AssemblyItem jumpInto{Instruction::JUMP};
jumpInto.setJumpType(AssemblyItem::JumpType::IntoFunction);
AssemblyItem jumpOutOf{Instruction::JUMP};
jumpOutOf.setJumpType(AssemblyItem::JumpType::OutOfFunction);
AssemblyItems items{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
jumpInto,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
Instruction::CALLVALUE,
Instruction::SWAP1,
jumpOutOf,
};
AssemblyItems expectation{
AssemblyItem(PushTag, 1),
Instruction::CALLVALUE,
Instruction::SWAP1,
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
Instruction::CALLVALUE,
Instruction::SWAP1,
jumpOutOf,
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_no_inline_type)
{
// Will not inline due to jump types.
AssemblyItems items{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
Instruction::CALLVALUE,
Instruction::SWAP1,
Instruction::JUMP,
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
items.begin(), items.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_no_inline)
{
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::CALLVALUE,
Instruction::JUMPI,
Instruction::JUMP,
};
AssemblyItems expectation{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::CALLVALUE,
Instruction::JUMPI,
Instruction::JUMP,
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_single_jump)
{
AssemblyItem jumpInto{Instruction::JUMP};
jumpInto.setJumpType(AssemblyItem::JumpType::IntoFunction);
AssemblyItem jumpOutOf{Instruction::JUMP};
jumpOutOf.setJumpType(AssemblyItem::JumpType::OutOfFunction);
AssemblyItems items{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
jumpInto,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
jumpOutOf,
};
AssemblyItems expectation{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
jumpOutOf,
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_end_of_bytecode)
{
AssemblyItem jumpInto{Instruction::JUMP};
jumpInto.setJumpType(AssemblyItem::JumpType::IntoFunction);
// Cannot inline, since the block at Tag_2 does not end in a jump.
AssemblyItems items{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
jumpInto,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
items.begin(), items.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_cse_break)
{
AssemblyItem jumpInto{Instruction::JUMP};
jumpInto.setJumpType(AssemblyItem::JumpType::IntoFunction);
AssemblyItem jumpOutOf{Instruction::JUMP};
jumpOutOf.setJumpType(AssemblyItem::JumpType::OutOfFunction);
// Could be inlined, but we only consider non-CSE-breaking blocks ending in JUMP so far.
AssemblyItems items{
AssemblyItem(PushTag, 1),
AssemblyItem(PushTag, 2),
jumpInto,
AssemblyItem(Tag, 1),
Instruction::STOP,
AssemblyItem(Tag, 2),
Instruction::STOP, // CSE breaking instruction
jumpOutOf
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
items.begin(), items.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_stop)
{
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::STOP
};
AssemblyItems expectation{
Instruction::STOP,
AssemblyItem(Tag, 1),
Instruction::STOP
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_stop_jumpi)
{
// Because of `jumpi`, will not be inlined.
AssemblyItems items{
u256(1),
AssemblyItem(PushTag, 1),
Instruction::JUMPI,
AssemblyItem(Tag, 1),
Instruction::STOP
};
AssemblyItems expectation = items;
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_revert)
{
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(0),
Instruction::DUP1,
Instruction::REVERT
};
AssemblyItems expectation{
u256(0),
Instruction::DUP1,
Instruction::REVERT,
AssemblyItem(Tag, 1),
u256(0),
Instruction::DUP1,
Instruction::REVERT
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_revert_increased_datagas)
{
// Inlining this would increase data gas (5 bytes v/s 4 bytes), therefore, skipped.
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
u256(0),
u256(0),
Instruction::REVERT
};
AssemblyItems expectation = items;
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_CASE(inliner_invalid)
{
AssemblyItems items{
AssemblyItem(PushTag, 1),
Instruction::JUMP,
AssemblyItem(Tag, 1),
Instruction::INVALID
};
AssemblyItems expectation = {
Instruction::INVALID,
AssemblyItem(Tag, 1),
Instruction::INVALID
};
Inliner{items, {}, 200, false, {}}.optimise();
BOOST_CHECK_EQUAL_COLLECTIONS(
items.begin(), items.end(),
expectation.begin(), expectation.end()
);
}
BOOST_AUTO_TEST_SUITE_END()
} // end namespaces