cerc-io/solidity
16
0
Fork 0
mirror of https://github.com/ethereum/solidity synced 2023-10-03 13:03:40 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Implement identity call in inline assembly

Browse Source
This commit is contained in:
Alex Beregszaszi 2016-12-02 13:14:18 +00:00 committed by chriseth
parent bf5dac1fb2
commit b93589b3b6
1 changed files with 21 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

35
libsolidity/codegen/CompilerUtils.cpp
View File

@ -300,6 +300,8 @@ void CompilerUtils::zeroInitialiseMemoryArray(ArrayType const& _type)
void CompilerUtils::memoryCopy(bool _useIdentityPrecompile)
{
//@TODO do not use ::CALL if less than 32 bytes?
// Stack here: size target source
if (!_useIdentityPrecompile)
@ -332,20 +334,25 @@ void CompilerUtils::memoryCopy(bool _useIdentityPrecompile)
m_context << Instruction::POP;
return;
}
// stack for call: outsize target size source value contract gas
//@TODO do not use ::CALL if less than 32 bytes?
m_context << Instruction::DUP3 << Instruction::SWAP1;
m_context << u256(0) << u256(identityContractAddress);
// compute gas costs
m_context << u256(32) << Instruction::DUP5 << u256(31) << Instruction::ADD;
static unsigned c_identityGas = 15;
static unsigned c_identityWordGas = 3;
m_context << Instruction::DIV << u256(c_identityWordGas) << Instruction::MUL;
m_context << u256(c_identityGas) << Instruction::ADD;
m_context << Instruction::CALL;
m_context << Instruction::ISZERO;
m_context.appendConditionalJumpTo(m_context.errorTag());
else
{
m_context.appendInlineAssembly(R"(
{
let words := div(add(len, 31), 32)
let cost := add(15, mul(3, words))
jump(invalidJumpLabel, iszero(call(cost, $identityContractAddress, 0, src, len, dst, len)))
}
)",
{ "len", "dst", "src" },
map<string, string> {
{ "$identityContractAddress", toString(identityContractAddress) }
}
);
m_context << Instruction::POP;
m_context << Instruction::POP;
m_context << Instruction::POP;
return;
}
}
void CompilerUtils::splitExternalFunctionType(bool _leftAligned)