Merge pull request #7324 from ethereum/activateLoadResolver

[Yul] Activate load resolver.
This commit is contained in:
chriseth 2019-09-09 16:45:41 +02:00 committed by GitHub
commit 96b6b45658
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12 changed files with 129 additions and 37 deletions

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@ -8,6 +8,7 @@ Compiler Features:
* ABI Output: Change sorting order of functions from selector to kind, name.
* Optimizer: Add rule that replaces the BYTE opcode by 0 if the first argument is larger than 31.
* Yul Optimizer: Take side-effect-freeness of user-defined functions into account.
* Yul Optimizer: Remove redundant mload/sload operations.
Bugfixes:

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@ -297,7 +297,7 @@ void DataFlowAnalyzer::clearValues(set<YulString> _variables)
void DataFlowAnalyzer::clearKnowledgeIfInvalidated(Block const& _block)
{
SideEffectsCollector sideEffects(m_dialect, _block);
SideEffectsCollector sideEffects(m_dialect, _block, &m_functionSideEffects);
if (sideEffects.invalidatesStorage())
m_storage.clear();
if (sideEffects.invalidatesMemory())
@ -306,7 +306,7 @@ void DataFlowAnalyzer::clearKnowledgeIfInvalidated(Block const& _block)
void DataFlowAnalyzer::clearKnowledgeIfInvalidated(Expression const& _expr)
{
SideEffectsCollector sideEffects(m_dialect, _expr);
SideEffectsCollector sideEffects(m_dialect, _expr, &m_functionSideEffects);
if (sideEffects.invalidatesStorage())
m_storage.clear();
if (sideEffects.invalidatesMemory())

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@ -23,6 +23,8 @@
#include <libyul/backends/evm/EVMDialect.h>
#include <libyul/optimiser/Semantics.h>
#include <libyul/optimiser/CallGraphGenerator.h>
#include <libyul/SideEffects.h>
#include <libyul/AsmData.h>
using namespace std;
@ -32,35 +34,53 @@ using namespace yul;
void LoadResolver::run(Dialect const& _dialect, Block& _ast)
{
bool containsMSize = MSizeFinder::containsMSize(_dialect, _ast);
LoadResolver{_dialect, !containsMSize}(_ast);
LoadResolver{
_dialect,
SideEffectsPropagator::sideEffects(_dialect, CallGraphGenerator::callGraph(_ast)),
!containsMSize
}(_ast);
}
void LoadResolver::visit(Expression& _e)
{
DataFlowAnalyzer::visit(_e);
if (!dynamic_cast<EVMDialect const*>(&m_dialect))
return;
if (_e.type() == typeid(FunctionCall))
{
FunctionCall const& funCall = boost::get<FunctionCall>(_e);
if (auto const* builtin = dynamic_cast<EVMDialect const&>(m_dialect).builtin(funCall.functionName.name))
if (!builtin->parameters.empty() && funCall.arguments.at(0).type() == typeid(Identifier))
{
YulString key = boost::get<Identifier>(funCall.arguments.at(0)).name;
if (
builtin->instruction == dev::eth::Instruction::SLOAD &&
m_storage.values.count(key)
)
{
_e = Identifier{locationOf(_e), m_storage.values[key]};
return;
}
else if (
m_optimizeMLoad &&
builtin->instruction == dev::eth::Instruction::MLOAD &&
m_memory.values.count(key)
)
{
_e = Identifier{locationOf(_e), m_memory.values[key]};
return;
}
}
if (builtin->instruction)
tryResolve(_e, *builtin->instruction, funCall.arguments);
}
else if (_e.type() == typeid(FunctionalInstruction))
{
FunctionalInstruction const& instruction = boost::get<FunctionalInstruction>(_e);
tryResolve(_e, instruction.instruction, instruction.arguments);
}
}
void LoadResolver::tryResolve(
Expression& _e,
dev::eth::Instruction _instruction,
vector<Expression> const& _arguments
)
{
if (_arguments.empty() || _arguments.at(0).type() != typeid(Identifier))
return;
YulString key = boost::get<Identifier>(_arguments.at(0)).name;
if (
_instruction == dev::eth::Instruction::SLOAD &&
m_storage.values.count(key)
)
_e = Identifier{locationOf(_e), m_storage.values[key]};
else if (
m_optimizeMLoad &&
_instruction == dev::eth::Instruction::MLOAD &&
m_memory.values.count(key)
)
_e = Identifier{locationOf(_e), m_memory.values[key]};
}

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@ -22,11 +22,13 @@
#pragma once
#include <libyul/optimiser/DataFlowAnalyzer.h>
#include <libevmasm/Instruction.h>
namespace yul
{
struct EVMDialect;
struct BuiltinFunctionForEVM;
/**
* Optimisation stage that replaces expressions of type ``sload(x)`` and ``mload(x)`` by the value
@ -39,11 +41,16 @@ struct EVMDialect;
class LoadResolver: public DataFlowAnalyzer
{
public:
/// Run the load resolver on the given complete AST.
static void run(Dialect const& _dialect, Block& _ast);
private:
LoadResolver(Dialect const& _dialect, bool _optimizeMLoad):
DataFlowAnalyzer(_dialect),
LoadResolver(
Dialect const& _dialect,
std::map<YulString, SideEffects> _functionSideEffects,
bool _optimizeMLoad
):
DataFlowAnalyzer(_dialect, std::move(_functionSideEffects)),
m_optimizeMLoad(_optimizeMLoad)
{}
@ -51,6 +58,12 @@ protected:
using ASTModifier::visit;
void visit(Expression& _e) override;
void tryResolve(
Expression& _e,
dev::eth::Instruction _instruction,
std::vector<Expression> const& _arguments
);
bool m_optimizeMLoad = false;
};

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@ -51,8 +51,12 @@ SideEffectsCollector::SideEffectsCollector(Dialect const& _dialect, Statement co
visit(_statement);
}
SideEffectsCollector::SideEffectsCollector(Dialect const& _dialect, Block const& _ast):
SideEffectsCollector(_dialect)
SideEffectsCollector::SideEffectsCollector(
Dialect const& _dialect,
Block const& _ast,
map<YulString, SideEffects> const* _functionSideEffects
):
SideEffectsCollector(_dialect, _functionSideEffects)
{
operator()(_ast);
}

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@ -47,7 +47,11 @@ public:
std::map<YulString, SideEffects> const* _functionSideEffects = nullptr
);
SideEffectsCollector(Dialect const& _dialect, Statement const& _statement);
SideEffectsCollector(Dialect const& _dialect, Block const& _ast);
SideEffectsCollector(
Dialect const& _dialect,
Block const& _ast,
std::map<YulString, SideEffects> const* _functionSideEffects = nullptr
);
using ASTWalker::operator();
void operator()(FunctionalInstruction const& _functionalInstruction) override;

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@ -45,6 +45,7 @@
#include <libyul/optimiser/StructuralSimplifier.h>
#include <libyul/optimiser/RedundantAssignEliminator.h>
#include <libyul/optimiser/VarNameCleaner.h>
#include <libyul/optimiser/LoadResolver.h>
#include <libyul/optimiser/Metrics.h>
#include <libyul/backends/evm/ConstantOptimiser.h>
#include <libyul/AsmAnalysis.h>
@ -118,6 +119,7 @@ void OptimiserSuite::run(
ExpressionSimplifier::run(_dialect, ast);
CommonSubexpressionEliminator::run(_dialect, ast);
LoadResolver::run(_dialect, ast);
}
{
@ -132,6 +134,7 @@ void OptimiserSuite::run(
{
// simplify again
LoadResolver::run(_dialect, ast);
CommonSubexpressionEliminator::run(_dialect, ast);
UnusedPruner::runUntilStabilisedOnFullAST(_dialect, ast, reservedIdentifiers);
}
@ -161,6 +164,7 @@ void OptimiserSuite::run(
RedundantAssignEliminator::run(_dialect, ast);
RedundantAssignEliminator::run(_dialect, ast);
CommonSubexpressionEliminator::run(_dialect, ast);
LoadResolver::run(_dialect, ast);
}
{
@ -176,6 +180,7 @@ void OptimiserSuite::run(
SSATransform::run(ast, dispenser);
RedundantAssignEliminator::run(_dialect, ast);
RedundantAssignEliminator::run(_dialect, ast);
LoadResolver::run(_dialect, ast);
ExpressionSimplifier::run(_dialect, ast);
StructuralSimplifier{_dialect}(ast);
BlockFlattener{}(ast);

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@ -21,11 +21,10 @@
// ----
// {
// {
// let _1 := 0x40
// mstore(_1, add(mload(_1), 0x20))
// let p := mload(_1)
// mstore(_1, add(p, _1))
// mstore(add(p, 96), 2)
// mstore(_1, 0x20)
// let _1 := mload(0x40)
// mstore(0x40, add(_1, 0x20))
// mstore(0x40, add(_1, 96))
// mstore(add(_1, 128), 2)
// mstore(0x40, 0x20)
// }
// }

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@ -10,6 +10,6 @@
// {
// sstore(4, 5)
// sstore(4, 3)
// sstore(8, sload(4))
// sstore(8, 3)
// }
// }

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@ -0,0 +1,18 @@
{
sstore(0, 123213)
for {let x := 0 let y} lt(x, sload(0)) {
x := add(x, 1)} {y := add(x, y)
}
}
// ====
// step: loadResolver
// ----
// {
// let _1 := 123213
// let _2 := 0
// sstore(_2, _1)
// let x := _2
// let y
// for { } lt(x, _1) { x := add(x, 1) }
// { y := add(x, y) }
// }

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@ -31,5 +31,5 @@
// mstore8(calldataload(_5), 4)
// sstore(_5, mload(_2))
// mstore(_2, _17)
// sstore(_5, mload(_2))
// sstore(_5, _17)
// }

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@ -0,0 +1,28 @@
{
function stores() { mstore(0, 1) }
function reads() { sstore(9, mload(7)) }
mstore(2, 9)
reads()
sstore(0, mload(2))
stores()
sstore(0, mload(2))
}
// ====
// step: loadResolver
// ----
// {
// function stores()
// { mstore(0, 1) }
// function reads()
// { sstore(9, mload(7)) }
// let _6 := 9
// let _7 := 2
// mstore(_7, _6)
// reads()
// let _9 := _6
// let _10 := 0
// sstore(_10, _9)
// stores()
// sstore(_10, mload(_7))
// }