aboutsummaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--libevmasm/Assembly.cpp33
-rw-r--r--libevmasm/Assembly.h3
-rw-r--r--libevmasm/PeepholeOptimiser.cpp146
-rw-r--r--libevmasm/PeepholeOptimiser.h53
-rw-r--r--libsolidity/codegen/Compiler.cpp6
-rw-r--r--libsolidity/codegen/CompilerContext.h2
6 files changed, 226 insertions, 17 deletions
diff --git a/libevmasm/Assembly.cpp b/libevmasm/Assembly.cpp
index 0ee3f421..a813a3a7 100644
--- a/libevmasm/Assembly.cpp
+++ b/libevmasm/Assembly.cpp
@@ -20,13 +20,17 @@
*/
#include "Assembly.h"
-#include <fstream>
+
#include <libevmasm/CommonSubexpressionEliminator.h>
#include <libevmasm/ControlFlowGraph.h>
+#include <libevmasm/PeepholeOptimiser.h>
#include <libevmasm/BlockDeduplicator.h>
#include <libevmasm/ConstantOptimiser.h>
#include <libevmasm/GasMeter.h>
+
+#include <fstream>
#include <json/json.h>
+
using namespace std;
using namespace dev;
using namespace dev::eth;
@@ -314,16 +318,15 @@ void Assembly::injectStart(AssemblyItem const& _i)
Assembly& Assembly::optimise(bool _enable, bool _isCreation, size_t _runs)
{
- if (_enable)
- optimiseInternal(_isCreation, _runs);
+ optimiseInternal(_enable, _isCreation, _runs);
return *this;
}
-map<u256, u256> Assembly::optimiseInternal(bool _isCreation, size_t _runs)
+map<u256, u256> Assembly::optimiseInternal(bool _enable, bool _isCreation, size_t _runs)
{
for (size_t subId = 0; subId < m_subs.size(); ++subId)
{
- map<u256, u256> subTagReplacements = m_subs[subId]->optimiseInternal(false, _runs);
+ map<u256, u256> subTagReplacements = m_subs[subId]->optimiseInternal(_enable, false, _runs);
BlockDeduplicator::applyTagReplacement(m_items, subTagReplacements, subId);
}
@@ -333,6 +336,13 @@ map<u256, u256> Assembly::optimiseInternal(bool _isCreation, size_t _runs)
{
count = 0;
+ PeepholeOptimiser peepOpt(m_items);
+ if (peepOpt.optimise())
+ count++;
+
+ if (!_enable)
+ continue;
+
// This only modifies PushTags, we have to run again to actually remove code.
BlockDeduplicator dedup(m_items);
if (dedup.deduplicate())
@@ -399,12 +409,13 @@ map<u256, u256> Assembly::optimiseInternal(bool _isCreation, size_t _runs)
}
}
- total += ConstantOptimisationMethod::optimiseConstants(
- _isCreation,
- _isCreation ? 1 : _runs,
- *this,
- m_items
- );
+ if (_enable)
+ total += ConstantOptimisationMethod::optimiseConstants(
+ _isCreation,
+ _isCreation ? 1 : _runs,
+ *this,
+ m_items
+ );
return tagReplacements;
}
diff --git a/libevmasm/Assembly.h b/libevmasm/Assembly.h
index 3ce82cce..f3c56610 100644
--- a/libevmasm/Assembly.h
+++ b/libevmasm/Assembly.h
@@ -101,6 +101,7 @@ public:
/// execution gas usage is optimised. @a _isCreation should be true for the top-level assembly.
/// @a _runs specifes an estimate on how often each opcode in this assembly will be executed,
/// i.e. use a small value to optimise for size and a large value to optimise for runtime.
+ /// If @a _enable is not set, will perform some simple peephole optimizations.
Assembly& optimise(bool _enable, bool _isCreation = true, size_t _runs = 200);
Json::Value stream(
std::ostream& _out,
@@ -112,7 +113,7 @@ public:
protected:
/// Does the same operations as @a optimise, but should only be applied to a sub and
/// returns the replaced tags.
- std::map<u256, u256> optimiseInternal(bool _isCreation, size_t _runs);
+ std::map<u256, u256> optimiseInternal(bool _enable, bool _isCreation, size_t _runs);
std::string locationFromSources(StringMap const& _sourceCodes, SourceLocation const& _location) const;
void donePath() { if (m_totalDeposit != INT_MAX && m_totalDeposit != m_deposit) BOOST_THROW_EXCEPTION(InvalidDeposit()); }
diff --git a/libevmasm/PeepholeOptimiser.cpp b/libevmasm/PeepholeOptimiser.cpp
new file mode 100644
index 00000000..91b0ece1
--- /dev/null
+++ b/libevmasm/PeepholeOptimiser.cpp
@@ -0,0 +1,146 @@
+/*
+ This file is part of cpp-ethereum.
+
+ cpp-ethereum 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.
+
+ cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @file PeepholeOptimiser.h
+ * Performs local optimising code changes to assembly.
+ */
+
+#include "PeepholeOptimiser.h"
+
+#include <libevmasm/AssemblyItem.h>
+#include <libevmasm/SemanticInformation.h>
+
+using namespace std;
+using namespace dev::eth;
+using namespace dev;
+
+// TODO: Extend this to use the tools from ExpressionClasses.cpp
+
+struct Identity
+{
+ static size_t windowSize() { return 1; }
+ static bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems> _out)
+ {
+ *_out = *_in;
+ return true;
+ }
+};
+
+struct PushPop
+{
+ static size_t windowSize() { return 2; }
+ static bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems>)
+ {
+ auto t = _in[0].type();
+ if (_in[1] == Instruction::POP && (
+ SemanticInformation::isDupInstruction(_in[0]) ||
+ t == Push || t == PushString || t == PushTag || t == PushSub ||
+ t == PushSubSize || t == PushProgramSize || t == PushData || t == PushLibraryAddress
+ ))
+ return true;
+ else
+ return false;
+ }
+};
+
+struct DoubleSwap
+{
+ static size_t windowSize() { return 2; }
+ static bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems>)
+ {
+ if (_in[0] == _in[1] && SemanticInformation::isSwapInstruction(_in[0]))
+ return true;
+ else
+ return false;
+ }
+};
+
+struct JumpToNext
+{
+ static size_t windowSize() { return 3; }
+ static bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems> _out)
+ {
+ if (
+ _in[0].type() == PushTag &&
+ (_in[1] == Instruction::JUMP || _in[1] == Instruction::JUMPI) &&
+ _in[2].type() == Tag &&
+ _in[0].data() == _in[2].data()
+ )
+ {
+ *_out = _in[2];
+ return true;
+ }
+ else
+ return false;
+ }
+};
+
+struct TagConjunctions
+{
+ static size_t windowSize() { return 3; }
+ static bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems> _out)
+ {
+ if (
+ _in[0].type() == PushTag &&
+ _in[2] == Instruction::AND &&
+ _in[1].type() == Push &&
+ (_in[1].data() & u256(0xFFFFFFFF)) == u256(0xFFFFFFFF)
+ )
+ {
+ *_out = _in[0];
+ return true;
+ }
+ else
+ return false;
+ }
+};
+
+struct OptimiserState
+{
+ AssemblyItems const& items;
+ size_t i;
+ std::back_insert_iterator<AssemblyItems> out;
+};
+
+void applyMethods(OptimiserState&)
+{
+ assertThrow(false, OptimizerException, "Peephole optimizer failed to apply identity.");
+}
+
+template <typename Method, typename... OtherMethods>
+void applyMethods(OptimiserState& _state, Method, OtherMethods... _other)
+{
+ if (_state.i + Method::windowSize() <= _state.items.size() && Method::apply(_state.items.begin() + _state.i, _state.out))
+ _state.i += Method::windowSize();
+ else
+ applyMethods(_state, _other...);
+}
+
+bool PeepholeOptimiser::optimise()
+{
+ OptimiserState state {m_items, 0, std::back_inserter(m_optimisedItems)};
+ while (state.i < m_items.size())
+ applyMethods(state, PushPop(), DoubleSwap(), JumpToNext(), TagConjunctions(), Identity());
+ if (m_optimisedItems.size() < m_items.size())
+ {
+ m_items = std::move(m_optimisedItems);
+ return true;
+ }
+ else
+ return false;
+
+}
diff --git a/libevmasm/PeepholeOptimiser.h b/libevmasm/PeepholeOptimiser.h
new file mode 100644
index 00000000..dfc9a03b
--- /dev/null
+++ b/libevmasm/PeepholeOptimiser.h
@@ -0,0 +1,53 @@
+/*
+ This file is part of cpp-ethereum.
+
+ cpp-ethereum 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.
+
+ cpp-ethereum 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 cpp-ethereum. If not, see <http://www.gnu.org/licenses/>.
+*/
+/**
+ * @file PeepholeOptimiser.h
+ * Performs local optimising code changes to assembly.
+ */
+#pragma once
+
+#include <vector>
+#include <cstddef>
+
+namespace dev
+{
+namespace eth
+{
+class AssemblyItem;
+using AssemblyItems = std::vector<AssemblyItem>;
+
+class PeepholeOptimisationMethod
+{
+public:
+ virtual size_t windowSize() const;
+ virtual bool apply(AssemblyItems::const_iterator _in, std::back_insert_iterator<AssemblyItems> _out);
+};
+
+class PeepholeOptimiser
+{
+public:
+ explicit PeepholeOptimiser(AssemblyItems& _items): m_items(_items) {}
+
+ bool optimise();
+
+private:
+ AssemblyItems& m_items;
+ AssemblyItems m_optimisedItems;
+};
+
+}
+}
diff --git a/libsolidity/codegen/Compiler.cpp b/libsolidity/codegen/Compiler.cpp
index eefa50c5..54639515 100644
--- a/libsolidity/codegen/Compiler.cpp
+++ b/libsolidity/codegen/Compiler.cpp
@@ -41,8 +41,7 @@ void Compiler::compileContract(
ContractCompiler creationCompiler(&runtimeCompiler, m_context, m_optimize);
m_runtimeSub = creationCompiler.compileConstructor(_contract, _contracts);
- if (m_optimize)
- m_context.optimise(m_optimizeRuns);
+ m_context.optimise(m_optimize, m_optimizeRuns);
if (_contract.isLibrary())
{
@@ -60,8 +59,7 @@ void Compiler::compileClone(
ContractCompiler cloneCompiler(&runtimeCompiler, m_context, m_optimize);
m_runtimeSub = cloneCompiler.compileClone(_contract, _contracts);
- if (m_optimize)
- m_context.optimise(m_optimizeRuns);
+ m_context.optimise(m_optimize, m_optimizeRuns);
}
eth::AssemblyItem Compiler::functionEntryLabel(FunctionDefinition const& _function) const
diff --git a/libsolidity/codegen/CompilerContext.h b/libsolidity/codegen/CompilerContext.h
index ee3fb068..8ccbddfd 100644
--- a/libsolidity/codegen/CompilerContext.h
+++ b/libsolidity/codegen/CompilerContext.h
@@ -155,7 +155,7 @@ public:
/// Prepends "PUSH <compiler version number> POP"
void injectVersionStampIntoSub(size_t _subIndex);
- void optimise(unsigned _runs = 200) { m_asm->optimise(true, true, _runs); }
+ void optimise(bool _fullOptimsation, unsigned _runs = 200) { m_asm->optimise(_fullOptimsation, true, _runs); }
/// @returns the runtime context if in creation mode and runtime context is set, nullptr otherwise.
CompilerContext* runtimeContext() { return m_runtimeContext; }
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-16 04:52:49 +0800