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-rw-r--r--libevmasm/Assembly.cpp9
-rw-r--r--libevmasm/AssemblyItem.cpp9
-rw-r--r--libevmasm/AssemblyItem.h3
-rw-r--r--libevmasm/ExpressionClasses.cpp11
-rw-r--r--libevmasm/ExpressionClasses.h3
-rw-r--r--libevmasm/GasMeter.cpp1
-rw-r--r--libevmasm/JumpdestRemover.cpp4
-rw-r--r--libevmasm/RuleList.h266
-rw-r--r--libevmasm/SemanticInformation.cpp26
-rw-r--r--libevmasm/SemanticInformation.h4
-rw-r--r--libevmasm/SimplificationRule.h45
-rw-r--r--libevmasm/SimplificationRules.cpp177
-rw-r--r--libevmasm/SimplificationRules.h11
13 files changed, 381 insertions, 188 deletions
diff --git a/libevmasm/Assembly.cpp b/libevmasm/Assembly.cpp
index 5fab24e1..b9fedf26 100644
--- a/libevmasm/Assembly.cpp
+++ b/libevmasm/Assembly.cpp
@@ -283,6 +283,11 @@ Json::Value Assembly::assemblyJSON(StringMap const& _sourceCodes) const
createJsonValue("PUSHLIB", i.location().start, i.location().end, m_libraries.at(h256(i.data())))
);
break;
+ case PushDeployTimeAddress:
+ collection.append(
+ createJsonValue("PUSHDEPLOYADDRESS", i.location().start, i.location().end)
+ );
+ break;
case Tag:
collection.append(
createJsonValue("tag", i.location().start, i.location().end, string(i.data())));
@@ -590,6 +595,10 @@ LinkerObject const& Assembly::assemble() const
ret.linkReferences[ret.bytecode.size()] = m_libraries.at(i.data());
ret.bytecode.resize(ret.bytecode.size() + 20);
break;
+ case PushDeployTimeAddress:
+ ret.bytecode.push_back(byte(Instruction::PUSH20));
+ ret.bytecode.resize(ret.bytecode.size() + 20);
+ break;
case Tag:
assertThrow(i.data() != 0, AssemblyException, "Invalid tag position.");
assertThrow(i.splitForeignPushTag().first == size_t(-1), AssemblyException, "Foreign tag.");
diff --git a/libevmasm/AssemblyItem.cpp b/libevmasm/AssemblyItem.cpp
index 64963021..5af618ff 100644
--- a/libevmasm/AssemblyItem.cpp
+++ b/libevmasm/AssemblyItem.cpp
@@ -68,6 +68,7 @@ unsigned AssemblyItem::bytesRequired(unsigned _addressLength) const
case PushSub:
return 1 + _addressLength;
case PushLibraryAddress:
+ case PushDeployTimeAddress:
return 1 + 20;
default:
break;
@@ -97,6 +98,7 @@ int AssemblyItem::returnValues() const
case PushSubSize:
case PushProgramSize:
case PushLibraryAddress:
+ case PushDeployTimeAddress:
return 1;
case Tag:
return 0;
@@ -119,6 +121,7 @@ bool AssemblyItem::canBeFunctional() const
case PushSubSize:
case PushProgramSize:
case PushLibraryAddress:
+ case PushDeployTimeAddress:
return true;
case Tag:
return false;
@@ -190,6 +193,9 @@ string AssemblyItem::toAssemblyText() const
case PushLibraryAddress:
text = string("linkerSymbol(\"") + toHex(data()) + string("\")");
break;
+ case PushDeployTimeAddress:
+ text = string("deployTimeAddress()");
+ break;
case UndefinedItem:
assertThrow(false, AssemblyException, "Invalid assembly item.");
break;
@@ -252,6 +258,9 @@ ostream& dev::eth::operator<<(ostream& _out, AssemblyItem const& _item)
_out << " PushLibraryAddress " << hash.substr(0, 8) + "..." + hash.substr(hash.length() - 8);
break;
}
+ case PushDeployTimeAddress:
+ _out << " PushDeployTimeAddress";
+ break;
case UndefinedItem:
_out << " ???";
break;
diff --git a/libevmasm/AssemblyItem.h b/libevmasm/AssemblyItem.h
index d38db927..5319a2b6 100644
--- a/libevmasm/AssemblyItem.h
+++ b/libevmasm/AssemblyItem.h
@@ -46,7 +46,8 @@ enum AssemblyItemType {
PushProgramSize,
Tag,
PushData,
- PushLibraryAddress ///< Push a currently unknown address of another (library) contract.
+ PushLibraryAddress, ///< Push a currently unknown address of another (library) contract.
+ PushDeployTimeAddress ///< Push an address to be filled at deploy time. Should not be touched by the optimizer.
};
class Assembly;
diff --git a/libevmasm/ExpressionClasses.cpp b/libevmasm/ExpressionClasses.cpp
index fc283b0b..69b33ec5 100644
--- a/libevmasm/ExpressionClasses.cpp
+++ b/libevmasm/ExpressionClasses.cpp
@@ -181,7 +181,7 @@ string ExpressionClasses::fullDAGToString(ExpressionClasses::Id _id) const
return str.str();
}
-ExpressionClasses::Id ExpressionClasses::tryToSimplify(Expression const& _expr, bool _secondRun)
+ExpressionClasses::Id ExpressionClasses::tryToSimplify(Expression const& _expr)
{
static Rules rules;
@@ -202,14 +202,7 @@ ExpressionClasses::Id ExpressionClasses::tryToSimplify(Expression const& _expr,
//cout << "with rule " << match->first.toString() << endl;
//ExpressionTemplate t(match->second());
//cout << "to " << match->second().toString() << endl;
- return rebuildExpression(ExpressionTemplate(match->second(), _expr.item->location()));
- }
-
- if (!_secondRun && _expr.arguments.size() == 2 && SemanticInformation::isCommutativeOperation(*_expr.item))
- {
- Expression expr = _expr;
- swap(expr.arguments[0], expr.arguments[1]);
- return tryToSimplify(expr, true);
+ return rebuildExpression(ExpressionTemplate(match->action(), _expr.item->location()));
}
return -1;
diff --git a/libevmasm/ExpressionClasses.h b/libevmasm/ExpressionClasses.h
index 6b426e97..df8082f9 100644
--- a/libevmasm/ExpressionClasses.h
+++ b/libevmasm/ExpressionClasses.h
@@ -108,8 +108,7 @@ public:
private:
/// Tries to simplify the given expression.
/// @returns its class if it possible or Id(-1) otherwise.
- /// @param _secondRun is set to true for the second run where arguments of commutative expressions are reversed
- Id tryToSimplify(Expression const& _expr, bool _secondRun = false);
+ Id tryToSimplify(Expression const& _expr);
/// Rebuilds an expression from a (matched) pattern.
Id rebuildExpression(ExpressionTemplate const& _template);
diff --git a/libevmasm/GasMeter.cpp b/libevmasm/GasMeter.cpp
index dad952bc..543f1cbc 100644
--- a/libevmasm/GasMeter.cpp
+++ b/libevmasm/GasMeter.cpp
@@ -52,6 +52,7 @@ GasMeter::GasConsumption GasMeter::estimateMax(AssemblyItem const& _item, bool _
case PushSubSize:
case PushProgramSize:
case PushLibraryAddress:
+ case PushDeployTimeAddress:
gas = runGas(Instruction::PUSH1);
break;
case Tag:
diff --git a/libevmasm/JumpdestRemover.cpp b/libevmasm/JumpdestRemover.cpp
index b6016798..60493a99 100644
--- a/libevmasm/JumpdestRemover.cpp
+++ b/libevmasm/JumpdestRemover.cpp
@@ -21,8 +21,6 @@
#include "JumpdestRemover.h"
-#include <libsolidity/interface/Exceptions.h>
-
#include <libevmasm/AssemblyItem.h>
using namespace std;
@@ -45,7 +43,7 @@ bool JumpdestRemover::optimise(set<size_t> const& _tagsReferencedFromOutside)
if (_item.type() != Tag)
return false;
auto asmIdAndTag = _item.splitForeignPushTag();
- solAssert(asmIdAndTag.first == size_t(-1), "Sub-assembly tag used as label.");
+ assertThrow(asmIdAndTag.first == size_t(-1), OptimizerException, "Sub-assembly tag used as label.");
size_t tag = asmIdAndTag.second;
return !references.count(tag);
}
diff --git a/libevmasm/RuleList.h b/libevmasm/RuleList.h
new file mode 100644
index 00000000..da522cec
--- /dev/null
+++ b/libevmasm/RuleList.h
@@ -0,0 +1,266 @@
+/*
+ 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/>.
+*/
+/**
+ * @date 2018
+ * Templatized list of simplification rules.
+ */
+
+#pragma once
+
+#include <vector>
+#include <functional>
+
+#include <libevmasm/Instruction.h>
+#include <libevmasm/SimplificationRule.h>
+
+#include <libdevcore/CommonData.h>
+
+namespace dev
+{
+namespace solidity
+{
+
+template <class S> S divWorkaround(S const& _a, S const& _b)
+{
+ return (S)(bigint(_a) / bigint(_b));
+}
+
+template <class S> S modWorkaround(S const& _a, S const& _b)
+{
+ return (S)(bigint(_a) % bigint(_b));
+}
+
+/// @returns a list of simplification rules given certain match placeholders.
+/// A, B and C should represent constants, X and Y arbitrary expressions.
+/// The simplifications should neven change the order of evaluation of
+/// arbitrary operations.
+template <class Pattern>
+std::vector<SimplificationRule<Pattern>> simplificationRuleList(
+ Pattern A,
+ Pattern B,
+ Pattern C,
+ Pattern X,
+ Pattern Y
+)
+{
+ std::vector<SimplificationRule<Pattern>> rules;
+ rules += std::vector<SimplificationRule<Pattern>>{
+ // arithmetics on constants
+ {{Instruction::ADD, {A, B}}, [=]{ return A.d() + B.d(); }, false},
+ {{Instruction::MUL, {A, B}}, [=]{ return A.d() * B.d(); }, false},
+ {{Instruction::SUB, {A, B}}, [=]{ return A.d() - B.d(); }, false},
+ {{Instruction::DIV, {A, B}}, [=]{ return B.d() == 0 ? 0 : divWorkaround(A.d(), B.d()); }, false},
+ {{Instruction::SDIV, {A, B}}, [=]{ return B.d() == 0 ? 0 : s2u(divWorkaround(u2s(A.d()), u2s(B.d()))); }, false},
+ {{Instruction::MOD, {A, B}}, [=]{ return B.d() == 0 ? 0 : modWorkaround(A.d(), B.d()); }, false},
+ {{Instruction::SMOD, {A, B}}, [=]{ return B.d() == 0 ? 0 : s2u(modWorkaround(u2s(A.d()), u2s(B.d()))); }, false},
+ {{Instruction::EXP, {A, B}}, [=]{ return u256(boost::multiprecision::powm(bigint(A.d()), bigint(B.d()), bigint(1) << 256)); }, false},
+ {{Instruction::NOT, {A}}, [=]{ return ~A.d(); }, false},
+ {{Instruction::LT, {A, B}}, [=]() -> u256 { return A.d() < B.d() ? 1 : 0; }, false},
+ {{Instruction::GT, {A, B}}, [=]() -> u256 { return A.d() > B.d() ? 1 : 0; }, false},
+ {{Instruction::SLT, {A, B}}, [=]() -> u256 { return u2s(A.d()) < u2s(B.d()) ? 1 : 0; }, false},
+ {{Instruction::SGT, {A, B}}, [=]() -> u256 { return u2s(A.d()) > u2s(B.d()) ? 1 : 0; }, false},
+ {{Instruction::EQ, {A, B}}, [=]() -> u256 { return A.d() == B.d() ? 1 : 0; }, false},
+ {{Instruction::ISZERO, {A}}, [=]() -> u256 { return A.d() == 0 ? 1 : 0; }, false},
+ {{Instruction::AND, {A, B}}, [=]{ return A.d() & B.d(); }, false},
+ {{Instruction::OR, {A, B}}, [=]{ return A.d() | B.d(); }, false},
+ {{Instruction::XOR, {A, B}}, [=]{ return A.d() ^ B.d(); }, false},
+ {{Instruction::BYTE, {A, B}}, [=]{ return A.d() >= 32 ? 0 : (B.d() >> unsigned(8 * (31 - A.d()))) & 0xff; }, false},
+ {{Instruction::ADDMOD, {A, B, C}}, [=]{ return C.d() == 0 ? 0 : u256((bigint(A.d()) + bigint(B.d())) % C.d()); }, false},
+ {{Instruction::MULMOD, {A, B, C}}, [=]{ return C.d() == 0 ? 0 : u256((bigint(A.d()) * bigint(B.d())) % C.d()); }, false},
+ {{Instruction::MULMOD, {A, B, C}}, [=]{ return A.d() * B.d(); }, false},
+ {{Instruction::SIGNEXTEND, {A, B}}, [=]() -> u256 {
+ if (A.d() >= 31)
+ return B.d();
+ unsigned testBit = unsigned(A.d()) * 8 + 7;
+ u256 mask = (u256(1) << testBit) - 1;
+ return u256(boost::multiprecision::bit_test(B.d(), testBit) ? B.d() | ~mask : B.d() & mask);
+ }, false},
+
+ // invariants involving known constants
+ {{Instruction::ADD, {X, 0}}, [=]{ return X; }, false},
+ {{Instruction::ADD, {0, X}}, [=]{ return X; }, false},
+ {{Instruction::SUB, {X, 0}}, [=]{ return X; }, false},
+ {{Instruction::MUL, {X, 0}}, [=]{ return u256(0); }, true},
+ {{Instruction::MUL, {0, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::MUL, {X, 1}}, [=]{ return X; }, false},
+ {{Instruction::MUL, {1, X}}, [=]{ return X; }, false},
+ {{Instruction::MUL, {X, u256(-1)}}, [=]() -> Pattern { return {Instruction::SUB, {0, X}}; }, false},
+ {{Instruction::MUL, {u256(-1), X}}, [=]() -> Pattern { return {Instruction::SUB, {0, X}}; }, false},
+ {{Instruction::DIV, {X, 0}}, [=]{ return u256(0); }, true},
+ {{Instruction::DIV, {0, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::DIV, {X, 1}}, [=]{ return X; }, false},
+ {{Instruction::SDIV, {X, 0}}, [=]{ return u256(0); }, true},
+ {{Instruction::SDIV, {0, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::SDIV, {X, 1}}, [=]{ return X; }, false},
+ {{Instruction::AND, {X, ~u256(0)}}, [=]{ return X; }, false},
+ {{Instruction::AND, {~u256(0), X}}, [=]{ return X; }, false},
+ {{Instruction::AND, {X, 0}}, [=]{ return u256(0); }, true},
+ {{Instruction::AND, {0, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::OR, {X, 0}}, [=]{ return X; }, false},
+ {{Instruction::OR, {0, X}}, [=]{ return X; }, false},
+ {{Instruction::OR, {X, ~u256(0)}}, [=]{ return ~u256(0); }, true},
+ {{Instruction::OR, {~u256(0), X}}, [=]{ return ~u256(0); }, true},
+ {{Instruction::XOR, {X, 0}}, [=]{ return X; }, false},
+ {{Instruction::XOR, {0, X}}, [=]{ return X; }, false},
+ {{Instruction::MOD, {X, 0}}, [=]{ return u256(0); }, true},
+ {{Instruction::MOD, {0, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::EQ, {X, 0}}, [=]() -> Pattern { return {Instruction::ISZERO, {X}}; }, false },
+ {{Instruction::EQ, {0, X}}, [=]() -> Pattern { return {Instruction::ISZERO, {X}}; }, false },
+
+ // operations involving an expression and itself
+ {{Instruction::AND, {X, X}}, [=]{ return X; }, true},
+ {{Instruction::OR, {X, X}}, [=]{ return X; }, true},
+ {{Instruction::XOR, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::SUB, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::EQ, {X, X}}, [=]{ return u256(1); }, true},
+ {{Instruction::LT, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::SLT, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::GT, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::SGT, {X, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::MOD, {X, X}}, [=]{ return u256(0); }, true},
+
+ // logical instruction combinations
+ {{Instruction::NOT, {{Instruction::NOT, {X}}}}, [=]{ return X; }, false},
+ {{Instruction::XOR, {X, {Instruction::XOR, {X, Y}}}}, [=]{ return Y; }, true},
+ {{Instruction::XOR, {X, {Instruction::XOR, {Y, X}}}}, [=]{ return Y; }, true},
+ {{Instruction::XOR, {{Instruction::XOR, {X, Y}}, X}}, [=]{ return Y; }, true},
+ {{Instruction::XOR, {{Instruction::XOR, {Y, X}}, X}}, [=]{ return Y; }, true},
+ {{Instruction::OR, {X, {Instruction::AND, {X, Y}}}}, [=]{ return X; }, true},
+ {{Instruction::OR, {X, {Instruction::AND, {Y, X}}}}, [=]{ return X; }, true},
+ {{Instruction::OR, {{Instruction::AND, {X, Y}}, X}}, [=]{ return X; }, true},
+ {{Instruction::OR, {{Instruction::AND, {Y, X}}, X}}, [=]{ return X; }, true},
+ {{Instruction::AND, {X, {Instruction::OR, {X, Y}}}}, [=]{ return X; }, true},
+ {{Instruction::AND, {X, {Instruction::OR, {Y, X}}}}, [=]{ return X; }, true},
+ {{Instruction::AND, {{Instruction::OR, {X, Y}}, X}}, [=]{ return X; }, true},
+ {{Instruction::AND, {{Instruction::OR, {Y, X}}, X}}, [=]{ return X; }, true},
+ {{Instruction::AND, {X, {Instruction::NOT, {X}}}}, [=]{ return u256(0); }, true},
+ {{Instruction::AND, {{Instruction::NOT, {X}}, X}}, [=]{ return u256(0); }, true},
+ {{Instruction::OR, {X, {Instruction::NOT, {X}}}}, [=]{ return ~u256(0); }, true},
+ {{Instruction::OR, {{Instruction::NOT, {X}}, X}}, [=]{ return ~u256(0); }, true},
+ };
+
+ // Replace MOD X, <power-of-two> with AND X, <power-of-two> - 1
+ for (size_t i = 0; i < 256; ++i)
+ {
+ u256 value = u256(1) << i;
+ rules.push_back({
+ {Instruction::MOD, {X, value}},
+ [=]() -> Pattern { return {Instruction::AND, {X, value - 1}}; },
+ false
+ });
+ }
+
+ // Double negation of opcodes with boolean result
+ for (auto const& op: std::vector<Instruction>{
+ Instruction::EQ,
+ Instruction::LT,
+ Instruction::SLT,
+ Instruction::GT,
+ Instruction::SGT
+ })
+ rules.push_back({
+ {Instruction::ISZERO, {{Instruction::ISZERO, {{op, {X, Y}}}}}},
+ [=]() -> Pattern { return {op, {X, Y}}; },
+ false
+ });
+
+ rules.push_back({
+ {Instruction::ISZERO, {{Instruction::ISZERO, {{Instruction::ISZERO, {X}}}}}},
+ [=]() -> Pattern { return {Instruction::ISZERO, {X}}; },
+ false
+ });
+
+ rules.push_back({
+ {Instruction::ISZERO, {{Instruction::XOR, {X, Y}}}},
+ [=]() -> Pattern { return { Instruction::EQ, {X, Y} }; },
+ false
+ });
+
+ // Associative operations
+ for (auto const& opFun: std::vector<std::pair<Instruction,std::function<u256(u256 const&,u256 const&)>>>{
+ {Instruction::ADD, std::plus<u256>()},
+ {Instruction::MUL, std::multiplies<u256>()},
+ {Instruction::AND, std::bit_and<u256>()},
+ {Instruction::OR, std::bit_or<u256>()},
+ {Instruction::XOR, std::bit_xor<u256>()}
+ })
+ {
+ auto op = opFun.first;
+ auto fun = opFun.second;
+ // Moving constants to the outside, order matters here - we first add rules
+ // for constants and then for non-constants.
+ // xa can be (X, A) or (A, X)
+ for (auto xa: {std::vector<Pattern>{X, A}, std::vector<Pattern>{A, X}})
+ {
+ rules += std::vector<SimplificationRule<Pattern>>{{
+ // (X+A)+B -> X+(A+B)
+ {op, {{op, xa}, B}},
+ [=]() -> Pattern { return {op, {X, fun(A.d(), B.d())}}; },
+ false
+ }, {
+ // (X+A)+Y -> (X+Y)+A
+ {op, {{op, xa}, Y}},
+ [=]() -> Pattern { return {op, {{op, {X, Y}}, A}}; },
+ false
+ }, {
+ // B+(X+A) -> X+(A+B)
+ {op, {B, {op, xa}}},
+ [=]() -> Pattern { return {op, {X, fun(A.d(), B.d())}}; },
+ false
+ }, {
+ // Y+(X+A) -> (Y+X)+A
+ {op, {Y, {op, xa}}},
+ [=]() -> Pattern { return {op, {{op, {Y, X}}, A}}; },
+ false
+ }};
+ }
+ }
+
+ // move constants across subtractions
+ rules += std::vector<SimplificationRule<Pattern>>{
+ {
+ // X - A -> X + (-A)
+ {Instruction::SUB, {X, A}},
+ [=]() -> Pattern { return {Instruction::ADD, {X, 0 - A.d()}}; },
+ false
+ }, {
+ // (X + A) - Y -> (X - Y) + A
+ {Instruction::SUB, {{Instruction::ADD, {X, A}}, Y}},
+ [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, A}}; },
+ false
+ }, {
+ // (A + X) - Y -> (X - Y) + A
+ {Instruction::SUB, {{Instruction::ADD, {A, X}}, Y}},
+ [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, A}}; },
+ false
+ }, {
+ // X - (Y + A) -> (X - Y) + (-A)
+ {Instruction::SUB, {X, {Instruction::ADD, {Y, A}}}},
+ [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, 0 - A.d()}}; },
+ false
+ }, {
+ // X - (A + Y) -> (X - Y) + (-A)
+ {Instruction::SUB, {X, {Instruction::ADD, {A, Y}}}},
+ [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, 0 - A.d()}}; },
+ false
+ }
+ };
+ return rules;
+}
+
+}
+}
diff --git a/libevmasm/SemanticInformation.cpp b/libevmasm/SemanticInformation.cpp
index 61a6ccda..03870f7c 100644
--- a/libevmasm/SemanticInformation.cpp
+++ b/libevmasm/SemanticInformation.cpp
@@ -35,6 +35,7 @@ bool SemanticInformation::breaksCSEAnalysisBlock(AssemblyItem const& _item)
default:
case UndefinedItem:
case Tag:
+ case PushDeployTimeAddress:
return true;
case Push:
case PushString:
@@ -153,6 +154,31 @@ bool SemanticInformation::isDeterministic(AssemblyItem const& _item)
}
}
+bool SemanticInformation::movable(Instruction _instruction)
+{
+ // These are not really functional.
+ if (isDupInstruction(_instruction) || isSwapInstruction(_instruction))
+ return false;
+ InstructionInfo info = instructionInfo(_instruction);
+ if (info.sideEffects)
+ return false;
+ switch (_instruction)
+ {
+ case Instruction::KECCAK256:
+ case Instruction::BALANCE:
+ case Instruction::EXTCODESIZE:
+ case Instruction::RETURNDATASIZE:
+ case Instruction::SLOAD:
+ case Instruction::PC:
+ case Instruction::MSIZE:
+ case Instruction::GAS:
+ return false;
+ default:
+ return true;
+ }
+ return true;
+}
+
bool SemanticInformation::invalidatesMemory(Instruction _instruction)
{
switch (_instruction)
diff --git a/libevmasm/SemanticInformation.h b/libevmasm/SemanticInformation.h
index e5ea7c18..83656252 100644
--- a/libevmasm/SemanticInformation.h
+++ b/libevmasm/SemanticInformation.h
@@ -49,6 +49,10 @@ struct SemanticInformation
/// @returns false if the value put on the stack by _item depends on anything else than
/// the information in the current block header, memory, storage or stack.
static bool isDeterministic(AssemblyItem const& _item);
+ /// @returns true if the instruction can be moved or copied (together with its arguments)
+ /// without altering the semantics. This means it cannot depend on storage or memory,
+ /// cannot have any side-effects, but it can depend on a call-constant state of the blockchain.
+ static bool movable(solidity::Instruction _instruction);
/// @returns true if the given instruction modifies memory.
static bool invalidatesMemory(solidity::Instruction _instruction);
/// @returns true if the given instruction modifies storage (even indirectly).
diff --git a/libevmasm/SimplificationRule.h b/libevmasm/SimplificationRule.h
new file mode 100644
index 00000000..7b4dea68
--- /dev/null
+++ b/libevmasm/SimplificationRule.h
@@ -0,0 +1,45 @@
+/*
+ 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/>.
+*/
+/**
+ * Expression simplification pattern.
+ */
+
+#pragma once
+
+#include <functional>
+
+namespace dev
+{
+namespace solidity
+{
+
+/**
+ * Rule that contains a pattern, an action that can be applied
+ * after the pattern has matched and a bool that indicates
+ * whether the action would remove something from the expression
+ * than is not a constant literal.
+ */
+template <class Pattern>
+struct SimplificationRule
+{
+ Pattern pattern;
+ std::function<Pattern()> action;
+ bool removesNonConstants;
+};
+
+}
+}
diff --git a/libevmasm/SimplificationRules.cpp b/libevmasm/SimplificationRules.cpp
index e6c51f95..53a5f9fc 100644
--- a/libevmasm/SimplificationRules.cpp
+++ b/libevmasm/SimplificationRules.cpp
@@ -23,7 +23,6 @@
#include <libevmasm/ExpressionClasses.h>
#include <utility>
-#include <tuple>
#include <functional>
#include <boost/range/adaptor/reversed.hpp>
#include <boost/noncopyable.hpp>
@@ -31,12 +30,14 @@
#include <libevmasm/CommonSubexpressionEliminator.h>
#include <libevmasm/SimplificationRules.h>
+#include <libevmasm/RuleList.h>
+
using namespace std;
using namespace dev;
using namespace dev::eth;
-pair<Pattern, function<Pattern()> > const* Rules::findFirstMatch(
+SimplificationRule<Pattern> const* Rules::findFirstMatch(
Expression const& _expr,
ExpressionClasses const& _classes
)
@@ -46,32 +47,22 @@ pair<Pattern, function<Pattern()> > const* Rules::findFirstMatch(
assertThrow(_expr.item, OptimizerException, "");
for (auto const& rule: m_rules[byte(_expr.item->instruction())])
{
- if (rule.first.matches(_expr, _classes))
+ if (rule.pattern.matches(_expr, _classes))
return &rule;
resetMatchGroups();
}
return nullptr;
}
-void Rules::addRules(std::vector<std::pair<Pattern, std::function<Pattern ()> > > const& _rules)
+void Rules::addRules(std::vector<SimplificationRule<Pattern>> const& _rules)
{
for (auto const& r: _rules)
addRule(r);
}
-void Rules::addRule(std::pair<Pattern, std::function<Pattern()> > const& _rule)
+void Rules::addRule(SimplificationRule<Pattern> const& _rule)
{
- m_rules[byte(_rule.first.instruction())].push_back(_rule);
-}
-
-template <class S> S divWorkaround(S const& _a, S const& _b)
-{
- return (S)(bigint(_a) / bigint(_b));
-}
-
-template <class S> S modWorkaround(S const& _a, S const& _b)
-{
- return (S)(bigint(_a) % bigint(_b));
+ m_rules[byte(_rule.pattern.instruction())].push_back(_rule);
}
Rules::Rules()
@@ -84,165 +75,13 @@ Rules::Rules()
// Anything.
Pattern X;
Pattern Y;
- Pattern Z;
A.setMatchGroup(1, m_matchGroups);
B.setMatchGroup(2, m_matchGroups);
C.setMatchGroup(3, m_matchGroups);
X.setMatchGroup(4, m_matchGroups);
Y.setMatchGroup(5, m_matchGroups);
- Z.setMatchGroup(6, m_matchGroups);
-
- addRules(vector<pair<Pattern, function<Pattern()>>>{
- // arithmetics on constants
- {{Instruction::ADD, {A, B}}, [=]{ return A.d() + B.d(); }},
- {{Instruction::MUL, {A, B}}, [=]{ return A.d() * B.d(); }},
- {{Instruction::SUB, {A, B}}, [=]{ return A.d() - B.d(); }},
- {{Instruction::DIV, {A, B}}, [=]{ return B.d() == 0 ? 0 : divWorkaround(A.d(), B.d()); }},
- {{Instruction::SDIV, {A, B}}, [=]{ return B.d() == 0 ? 0 : s2u(divWorkaround(u2s(A.d()), u2s(B.d()))); }},
- {{Instruction::MOD, {A, B}}, [=]{ return B.d() == 0 ? 0 : modWorkaround(A.d(), B.d()); }},
- {{Instruction::SMOD, {A, B}}, [=]{ return B.d() == 0 ? 0 : s2u(modWorkaround(u2s(A.d()), u2s(B.d()))); }},
- {{Instruction::EXP, {A, B}}, [=]{ return u256(boost::multiprecision::powm(bigint(A.d()), bigint(B.d()), bigint(1) << 256)); }},
- {{Instruction::NOT, {A}}, [=]{ return ~A.d(); }},
- {{Instruction::LT, {A, B}}, [=]() -> u256 { return A.d() < B.d() ? 1 : 0; }},
- {{Instruction::GT, {A, B}}, [=]() -> u256 { return A.d() > B.d() ? 1 : 0; }},
- {{Instruction::SLT, {A, B}}, [=]() -> u256 { return u2s(A.d()) < u2s(B.d()) ? 1 : 0; }},
- {{Instruction::SGT, {A, B}}, [=]() -> u256 { return u2s(A.d()) > u2s(B.d()) ? 1 : 0; }},
- {{Instruction::EQ, {A, B}}, [=]() -> u256 { return A.d() == B.d() ? 1 : 0; }},
- {{Instruction::ISZERO, {A}}, [=]() -> u256 { return A.d() == 0 ? 1 : 0; }},
- {{Instruction::AND, {A, B}}, [=]{ return A.d() & B.d(); }},
- {{Instruction::OR, {A, B}}, [=]{ return A.d() | B.d(); }},
- {{Instruction::XOR, {A, B}}, [=]{ return A.d() ^ B.d(); }},
- {{Instruction::BYTE, {A, B}}, [=]{ return A.d() >= 32 ? 0 : (B.d() >> unsigned(8 * (31 - A.d()))) & 0xff; }},
- {{Instruction::ADDMOD, {A, B, C}}, [=]{ return C.d() == 0 ? 0 : u256((bigint(A.d()) + bigint(B.d())) % C.d()); }},
- {{Instruction::MULMOD, {A, B, C}}, [=]{ return C.d() == 0 ? 0 : u256((bigint(A.d()) * bigint(B.d())) % C.d()); }},
- {{Instruction::MULMOD, {A, B, C}}, [=]{ return A.d() * B.d(); }},
- {{Instruction::SIGNEXTEND, {A, B}}, [=]() -> u256 {
- if (A.d() >= 31)
- return B.d();
- unsigned testBit = unsigned(A.d()) * 8 + 7;
- u256 mask = (u256(1) << testBit) - 1;
- return u256(boost::multiprecision::bit_test(B.d(), testBit) ? B.d() | ~mask : B.d() & mask);
- }},
-
- // invariants involving known constants (commutative instructions will be checked with swapped operants too)
- {{Instruction::ADD, {X, 0}}, [=]{ return X; }},
- {{Instruction::SUB, {X, 0}}, [=]{ return X; }},
- {{Instruction::MUL, {X, 0}}, [=]{ return u256(0); }},
- {{Instruction::MUL, {X, 1}}, [=]{ return X; }},
- {{Instruction::DIV, {X, 0}}, [=]{ return u256(0); }},
- {{Instruction::DIV, {0, X}}, [=]{ return u256(0); }},
- {{Instruction::DIV, {X, 1}}, [=]{ return X; }},
- {{Instruction::SDIV, {X, 0}}, [=]{ return u256(0); }},
- {{Instruction::SDIV, {0, X}}, [=]{ return u256(0); }},
- {{Instruction::SDIV, {X, 1}}, [=]{ return X; }},
- {{Instruction::AND, {X, ~u256(0)}}, [=]{ return X; }},
- {{Instruction::AND, {X, 0}}, [=]{ return u256(0); }},
- {{Instruction::OR, {X, 0}}, [=]{ return X; }},
- {{Instruction::OR, {X, ~u256(0)}}, [=]{ return ~u256(0); }},
- {{Instruction::XOR, {X, 0}}, [=]{ return X; }},
- {{Instruction::MOD, {X, 0}}, [=]{ return u256(0); }},
- {{Instruction::MOD, {0, X}}, [=]{ return u256(0); }},
- {{Instruction::EQ, {X, 0}}, [=]() -> Pattern { return {Instruction::ISZERO, {X}}; } },
-
- // operations involving an expression and itself
- {{Instruction::AND, {X, X}}, [=]{ return X; }},
- {{Instruction::OR, {X, X}}, [=]{ return X; }},
- {{Instruction::XOR, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::SUB, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::EQ, {X, X}}, [=]{ return u256(1); }},
- {{Instruction::LT, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::SLT, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::GT, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::SGT, {X, X}}, [=]{ return u256(0); }},
- {{Instruction::MOD, {X, X}}, [=]{ return u256(0); }},
-
- // logical instruction combinations
- {{Instruction::NOT, {{Instruction::NOT, {X}}}}, [=]{ return X; }},
- {{Instruction::XOR, {{{X}, {Instruction::XOR, {X, Y}}}}}, [=]{ return Y; }},
- {{Instruction::OR, {{{X}, {Instruction::AND, {X, Y}}}}}, [=]{ return X; }},
- {{Instruction::AND, {{{X}, {Instruction::OR, {X, Y}}}}}, [=]{ return X; }},
- {{Instruction::AND, {{{X}, {Instruction::NOT, {X}}}}}, [=]{ return u256(0); }},
- {{Instruction::OR, {{{X}, {Instruction::NOT, {X}}}}}, [=]{ return ~u256(0); }},
- });
-
- // Double negation of opcodes with binary result
- for (auto const& op: vector<Instruction>{
- Instruction::EQ,
- Instruction::LT,
- Instruction::SLT,
- Instruction::GT,
- Instruction::SGT
- })
- addRule({
- {Instruction::ISZERO, {{Instruction::ISZERO, {{op, {X, Y}}}}}},
- [=]() -> Pattern { return {op, {X, Y}}; }
- });
-
- addRule({
- {Instruction::ISZERO, {{Instruction::ISZERO, {{Instruction::ISZERO, {X}}}}}},
- [=]() -> Pattern { return {Instruction::ISZERO, {X}}; }
- });
-
- addRule({
- {Instruction::ISZERO, {{Instruction::XOR, {X, Y}}}},
- [=]() -> Pattern { return { Instruction::EQ, {X, Y} }; }
- });
-
- // Associative operations
- for (auto const& opFun: vector<pair<Instruction,function<u256(u256 const&,u256 const&)>>>{
- {Instruction::ADD, plus<u256>()},
- {Instruction::MUL, multiplies<u256>()},
- {Instruction::AND, bit_and<u256>()},
- {Instruction::OR, bit_or<u256>()},
- {Instruction::XOR, bit_xor<u256>()}
- })
- {
- auto op = opFun.first;
- auto fun = opFun.second;
- // Moving constants to the outside, order matters here!
- // we need actions that return expressions (or patterns?) here, and we need also reversed rules
- // (X+A)+B -> X+(A+B)
- addRules(vector<pair<Pattern, function<Pattern()>>>{{
- {op, {{op, {X, A}}, B}},
- [=]() -> Pattern { return {op, {X, fun(A.d(), B.d())}}; }
- }, {
- // X+(Y+A) -> (X+Y)+A
- {op, {{op, {X, A}}, Y}},
- [=]() -> Pattern { return {op, {{op, {X, Y}}, A}}; }
- }, {
- // For now, we still need explicit commutativity for the inner pattern
- {op, {{op, {A, X}}, B}},
- [=]() -> Pattern { return {op, {X, fun(A.d(), B.d())}}; }
- }, {
- {op, {{op, {A, X}}, Y}},
- [=]() -> Pattern { return {op, {{op, {X, Y}}, A}}; }
- }});
- }
- // move constants across subtractions
- addRules(vector<pair<Pattern, function<Pattern()>>>{
- {
- // X - A -> X + (-A)
- {Instruction::SUB, {X, A}},
- [=]() -> Pattern { return {Instruction::ADD, {X, 0 - A.d()}}; }
- }, {
- // (X + A) - Y -> (X - Y) + A
- {Instruction::SUB, {{Instruction::ADD, {X, A}}, Y}},
- [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, A}}; }
- }, {
- // (A + X) - Y -> (X - Y) + A
- {Instruction::SUB, {{Instruction::ADD, {A, X}}, Y}},
- [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, A}}; }
- }, {
- // X - (Y + A) -> (X - Y) + (-A)
- {Instruction::SUB, {X, {Instruction::ADD, {Y, A}}}},
- [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, 0 - A.d()}}; }
- }, {
- // X - (A + Y) -> (X - Y) + (-A)
- {Instruction::SUB, {X, {Instruction::ADD, {A, Y}}}},
- [=]() -> Pattern { return {Instruction::ADD, {{Instruction::SUB, {X, Y}}, 0 - A.d()}}; }
- }
- });
+ addRules(simplificationRuleList(A, B, C, X, Y));
}
Pattern::Pattern(Instruction _instruction, std::vector<Pattern> const& _arguments):
diff --git a/libevmasm/SimplificationRules.h b/libevmasm/SimplificationRules.h
index a4da5849..53f7e595 100644
--- a/libevmasm/SimplificationRules.h
+++ b/libevmasm/SimplificationRules.h
@@ -24,6 +24,7 @@
#pragma once
#include <libevmasm/ExpressionClasses.h>
+#include <libevmasm/SimplificationRule.h>
#include <functional>
#include <vector>
@@ -47,19 +48,21 @@ public:
/// @returns a pointer to the first matching pattern and sets the match
/// groups accordingly.
- std::pair<Pattern, std::function<Pattern()>> const* findFirstMatch(
+ SimplificationRule<Pattern> const* findFirstMatch(
Expression const& _expr,
ExpressionClasses const& _classes
);
private:
- void addRules(std::vector<std::pair<Pattern, std::function<Pattern()>>> const& _rules);
- void addRule(std::pair<Pattern, std::function<Pattern()>> const& _rule);
+ void addRules(std::vector<SimplificationRule<Pattern>> const& _rules);
+ void addRule(SimplificationRule<Pattern> const& _rule);
void resetMatchGroups() { m_matchGroups.clear(); }
std::map<unsigned, Expression const*> m_matchGroups;
- std::vector<std::pair<Pattern, std::function<Pattern()>>> m_rules[256];
+ /// Pattern to match, replacement to be applied and flag indicating whether
+ /// the replacement might remove some elements (except constants).
+ std::vector<SimplificationRule<Pattern>> m_rules[256];
};
/**
generated by cgit v1.2.3 (git 2.25.1) at 2025-04-28 14:26:36 +0800