Merge pull request #3797 from ethereum/shift-constantinople

Use native shift instructions on Constantinople
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chriseth 2018-05-02 16:50:15 +02:00 committed by GitHub
commit a856135bbf
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10 changed files with 126 additions and 55 deletions

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@ -2,6 +2,7 @@
Features:
* Build System: Update internal dependency of jsoncpp to 1.8.4, which introduces more strictness and reduces memory usage.
* Code Generator: Use native shift instructions on target Constantinople.
* Optimizer: Remove unnecessary masking of the result of known short instructions (``ADDRESS``, ``CALLER``, ``ORIGIN`` and ``COINBASE``).
* Type Checker: Deprecate the ``years`` unit denomination and raise a warning for it (or an error as experimental 0.5.0 feature).
* Type Checker: Make literals (without explicit type casting) an error for tight packing as experimental 0.5.0 feature.

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@ -371,7 +371,7 @@ string ABIFunctions::conversionFunction(Type const& _from, Type const& _to)
if (toCategory == Type::Category::Integer)
body =
Whiskers("converted := <convert>(<shift>(value))")
("shift", shiftRightFunction(256 - from.numBytes() * 8, false))
("shift", shiftRightFunction(256 - from.numBytes() * 8))
("convert", conversionFunction(IntegerType(from.numBytes() * 8), _to))
.render();
else
@ -458,8 +458,8 @@ string ABIFunctions::splitExternalFunctionIdFunction()
}
)")
("functionName", functionName)
("shr32", shiftRightFunction(32, false))
("shr64", shiftRightFunction(64, false))
("shr32", shiftRightFunction(32))
("shr64", shiftRightFunction(64))
.render();
});
}
@ -831,7 +831,7 @@ string ABIFunctions::abiEncodingFunctionCompactStorageArray(
templ("encodeToMemoryFun", encodeToMemoryFun);
std::vector<std::map<std::string, std::string>> items(itemsPerSlot);
for (size_t i = 0; i < itemsPerSlot; ++i)
items[i]["shiftRightFun"] = shiftRightFunction(i * storageBytes * 8, false);
items[i]["shiftRightFun"] = shiftRightFunction(i * storageBytes * 8);
templ("items", items);
return templ.render();
}
@ -927,7 +927,7 @@ string ABIFunctions::abiEncodingFunctionStruct(
}
else
memberTempl("preprocess", "");
memberTempl("retrieveValue", shiftRightFunction(intraSlotOffset * 8, false) + "(slotValue)");
memberTempl("retrieveValue", shiftRightFunction(intraSlotOffset * 8) + "(slotValue)");
}
else
{
@ -1401,37 +1401,75 @@ string ABIFunctions::copyToMemoryFunction(bool _fromCalldata)
string ABIFunctions::shiftLeftFunction(size_t _numBits)
{
solAssert(_numBits < 256, "");
string functionName = "shift_left_" + to_string(_numBits);
return createFunction(functionName, [&]() {
solAssert(_numBits < 256, "");
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := mul(value, <multiplier>)
}
)")
("functionName", functionName)
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
if (m_evmVersion.hasBitwiseShifting())
{
return createFunction(functionName, [&]() {
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := shl(<numBits>, value)
}
)")
("functionName", functionName)
("numBits", to_string(_numBits))
.render();
});
}
else
{
return createFunction(functionName, [&]() {
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := mul(value, <multiplier>)
}
)")
("functionName", functionName)
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
}
}
string ABIFunctions::shiftRightFunction(size_t _numBits, bool _signed)
string ABIFunctions::shiftRightFunction(size_t _numBits)
{
string functionName = "shift_right_" + to_string(_numBits) + (_signed ? "_signed" : "_unsigned");
return createFunction(functionName, [&]() {
solAssert(_numBits < 256, "");
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := <div>(value, <multiplier>)
}
)")
("functionName", functionName)
("div", _signed ? "sdiv" : "div")
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
solAssert(_numBits < 256, "");
// Note that if this is extended with signed shifts,
// the opcodes SAR and SDIV behave differently with regards to rounding!
string functionName = "shift_right_" + to_string(_numBits) + "_unsigned";
if (m_evmVersion.hasBitwiseShifting())
{
return createFunction(functionName, [&]() {
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := shr(<numBits>, value)
}
)")
("functionName", functionName)
("numBits", to_string(_numBits))
.render();
});
}
else
{
return createFunction(functionName, [&]() {
return
Whiskers(R"(
function <functionName>(value) -> newValue {
newValue := div(value, <multiplier>)
}
)")
("functionName", functionName)
("multiplier", toCompactHexWithPrefix(u256(1) << _numBits))
.render();
});
}
}
string ABIFunctions::roundUpFunction()

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@ -22,6 +22,8 @@
#pragma once
#include <libsolidity/interface/EVMVersion.h>
#include <libsolidity/ast/ASTForward.h>
#include <vector>
@ -48,6 +50,8 @@ using TypePointers = std::vector<TypePointer>;
class ABIFunctions
{
public:
explicit ABIFunctions(EVMVersion _evmVersion = EVMVersion{}) : m_evmVersion(_evmVersion) {}
/// @returns name of an assembly function to ABI-encode values of @a _givenTypes
/// into memory, converting the types to @a _targetTypes on the fly.
/// Parameters are: <headStart> <value_n> ... <value_1>, i.e.
@ -191,7 +195,7 @@ private:
std::string copyToMemoryFunction(bool _fromCalldata);
std::string shiftLeftFunction(size_t _numBits);
std::string shiftRightFunction(size_t _numBits, bool _signed);
std::string shiftRightFunction(size_t _numBits);
/// @returns the name of a function that rounds its input to the next multiple
/// of 32 or the input if it is a multiple of 32.
std::string roundUpFunction();
@ -225,6 +229,8 @@ private:
/// Map from function name to code for a multi-use function.
std::map<std::string, std::string> m_requestedFunctions;
EVMVersion m_evmVersion;
};
}

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@ -55,7 +55,8 @@ public:
explicit CompilerContext(EVMVersion _evmVersion = EVMVersion{}, CompilerContext* _runtimeContext = nullptr):
m_asm(std::make_shared<eth::Assembly>()),
m_evmVersion(_evmVersion),
m_runtimeContext(_runtimeContext)
m_runtimeContext(_runtimeContext),
m_abiFunctions(m_evmVersion)
{
if (m_runtimeContext)
m_runtimeSub = size_t(m_asm->newSub(m_runtimeContext->m_asm).data());

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@ -599,15 +599,15 @@ void CompilerUtils::splitExternalFunctionType(bool _leftAligned)
if (_leftAligned)
{
m_context << Instruction::DUP1;
rightShiftNumberOnStack(64 + 32, false);
rightShiftNumberOnStack(64 + 32);
// <input> <address>
m_context << Instruction::SWAP1;
rightShiftNumberOnStack(64, false);
rightShiftNumberOnStack(64);
}
else
{
m_context << Instruction::DUP1;
rightShiftNumberOnStack(32, false);
rightShiftNumberOnStack(32);
m_context << ((u256(1) << 160) - 1) << Instruction::AND << Instruction::SWAP1;
}
m_context << u256(0xffffffffUL) << Instruction::AND;
@ -675,7 +675,7 @@ void CompilerUtils::convertType(
// conversion from bytes to integer. no need to clean the high bit
// only to shift right because of opposite alignment
IntegerType const& targetIntegerType = dynamic_cast<IntegerType const&>(_targetType);
rightShiftNumberOnStack(256 - typeOnStack.numBytes() * 8, false);
rightShiftNumberOnStack(256 - typeOnStack.numBytes() * 8);
if (targetIntegerType.numBits() < typeOnStack.numBytes() * 8)
convertType(IntegerType(typeOnStack.numBytes() * 8), _targetType, _cleanupNeeded);
}
@ -1242,7 +1242,7 @@ unsigned CompilerUtils::loadFromMemoryHelper(Type const& _type, bool _fromCallda
bool leftAligned = _type.category() == Type::Category::FixedBytes;
// add leading or trailing zeros by dividing/multiplying depending on alignment
int shiftFactor = (32 - numBytes) * 8;
rightShiftNumberOnStack(shiftFactor, false);
rightShiftNumberOnStack(shiftFactor);
if (leftAligned)
leftShiftNumberOnStack(shiftFactor);
}
@ -1265,13 +1265,20 @@ void CompilerUtils::cleanHigherOrderBits(IntegerType const& _typeOnStack)
void CompilerUtils::leftShiftNumberOnStack(unsigned _bits)
{
solAssert(_bits < 256, "");
m_context << (u256(1) << _bits) << Instruction::MUL;
if (m_context.evmVersion().hasBitwiseShifting())
m_context << _bits << Instruction::SHL;
else
m_context << (u256(1) << _bits) << Instruction::MUL;
}
void CompilerUtils::rightShiftNumberOnStack(unsigned _bits, bool _isSigned)
void CompilerUtils::rightShiftNumberOnStack(unsigned _bits)
{
solAssert(_bits < 256, "");
m_context << (u256(1) << _bits) << Instruction::SWAP1 << (_isSigned ? Instruction::SDIV : Instruction::DIV);
// NOTE: If we add signed right shift, SAR rounds differently than SDIV
if (m_context.evmVersion().hasBitwiseShifting())
m_context << _bits << Instruction::SHR;
else
m_context << (u256(1) << _bits) << Instruction::SWAP1 << Instruction::DIV;
}
unsigned CompilerUtils::prepareMemoryStore(Type const& _type, bool _padToWords)

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@ -254,7 +254,7 @@ public:
/// Helper function to shift top value on the stack to the right.
/// Stack pre: <value> <shift_by_bits>
/// Stack post: <shifted_value>
void rightShiftNumberOnStack(unsigned _bits, bool _isSigned = false);
void rightShiftNumberOnStack(unsigned _bits);
/// Appends code that computes tha Keccak-256 hash of the topmost stack element of 32 byte type.
void computeHashStatic();

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@ -548,7 +548,7 @@ bool ExpressionCompiler::visit(FunctionCall const& _functionCall)
if (m_context.runtimeContext())
// We have a runtime context, so we need the creation part.
utils().rightShiftNumberOnStack(32, false);
utils().rightShiftNumberOnStack(32);
else
// Extract the runtime part.
m_context << ((u256(1) << 32) - 1) << Instruction::AND;
@ -1706,13 +1706,23 @@ void ExpressionCompiler::appendShiftOperatorCode(Token::Value _operator, Type co
m_context.appendConditionalInvalid();
}
m_context << Instruction::SWAP1;
// stack: value_to_shift shift_amount
switch (_operator)
{
case Token::SHL:
m_context << Instruction::SWAP1 << u256(2) << Instruction::EXP << Instruction::MUL;
if (m_context.evmVersion().hasBitwiseShifting())
m_context << Instruction::SHL;
else
m_context << u256(2) << Instruction::EXP << Instruction::MUL;
break;
case Token::SAR:
m_context << Instruction::SWAP1 << u256(2) << Instruction::EXP << Instruction::SWAP1 << (c_valueSigned ? Instruction::SDIV : Instruction::DIV);
// NOTE: SAR rounds differently than SDIV
if (m_context.evmVersion().hasBitwiseShifting() && !c_valueSigned)
m_context << Instruction::SHR;
else
m_context << u256(2) << Instruction::EXP << Instruction::SWAP1 << (c_valueSigned ? Instruction::SDIV : Instruction::DIV);
break;
case Token::SHR:
default:

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@ -267,7 +267,7 @@ void StorageItem::storeValue(Type const& _sourceType, SourceLocation const& _loc
else if (m_dataType->category() == Type::Category::FixedBytes)
{
solAssert(_sourceType.category() == Type::Category::FixedBytes, "source not fixed bytes");
CompilerUtils(m_context).rightShiftNumberOnStack(256 - 8 * dynamic_cast<FixedBytesType const&>(*m_dataType).numBytes(), false);
CompilerUtils(m_context).rightShiftNumberOnStack(256 - 8 * dynamic_cast<FixedBytesType const&>(*m_dataType).numBytes());
}
else
{

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@ -136,13 +136,22 @@ GasEstimator::GasConsumption GasEstimator::functionalEstimation(
ExpressionClasses& classes = state->expressionClasses();
using Id = ExpressionClasses::Id;
using Ids = vector<Id>;
// div(calldataload(0), 1 << 224) equals to hashValue
Id hashValue = classes.find(u256(FixedHash<4>::Arith(FixedHash<4>(dev::keccak256(_signature)))));
Id calldata = classes.find(Instruction::CALLDATALOAD, Ids{classes.find(u256(0))});
classes.forceEqual(hashValue, Instruction::DIV, Ids{
calldata,
classes.find(u256(1) << 224)
});
if (!m_evmVersion.hasBitwiseShifting())
// div(calldataload(0), 1 << 224) equals to hashValue
classes.forceEqual(
hashValue,
Instruction::DIV,
Ids{calldata, classes.find(u256(1) << 224)}
);
else
// shr(0xe0, calldataload(0)) equals to hashValue
classes.forceEqual(
hashValue,
Instruction::SHR,
Ids{classes.find(u256(0xe0)), calldata}
);
// lt(calldatasize(), 4) equals to 0 (ignore the shortcut for fallback functions)
classes.forceEqual(
classes.find(u256(0)),

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@ -158,8 +158,9 @@ BOOST_AUTO_TEST_CASE(location_test)
}
)";
AssemblyItems items = compileContract(sourceCode);
bool hasShifts = dev::test::Options::get().evmVersion().hasBitwiseShifting();
vector<SourceLocation> locations =
vector<SourceLocation>(24, SourceLocation(2, 75, make_shared<string>(""))) +
vector<SourceLocation>(hasShifts ? 23 : 24, SourceLocation(2, 75, make_shared<string>(""))) +
vector<SourceLocation>(2, SourceLocation(20, 72, make_shared<string>(""))) +
vector<SourceLocation>(1, SourceLocation(8, 17, make_shared<string>("--CODEGEN--"))) +
vector<SourceLocation>(3, SourceLocation(5, 7, make_shared<string>("--CODEGEN--"))) +
@ -172,8 +173,6 @@ BOOST_AUTO_TEST_CASE(location_test)
vector<SourceLocation>(1, SourceLocation(65, 67, make_shared<string>(""))) +
vector<SourceLocation>(2, SourceLocation(58, 67, make_shared<string>(""))) +
vector<SourceLocation>(2, SourceLocation(20, 72, make_shared<string>("")));
checkAssemblyLocations(items, locations);
}