cerc-io/solidity
11
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

Name and rename things.

Browse Source
This commit is contained in:
Daniel Kirchner 2021-03-09 17:51:53 +01:00
parent c08f087742
commit a5a99620dc
1 changed files with 19 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
libyul/backends/evm/EVMCodeTransform.cpp
View File

@ -532,24 +532,30 @@ void CodeTransform::operator()(FunctionDefinition const& _function)
{
// This vector stores true for stack slots containing return labels or return values,
// false otherwise.
vector<bool> stackLayout(static_cast<size_t>(m_assembly.stackHeight()), false);
stackLayout[0] = true;
vector<bool> keep(static_cast<size_t>(m_assembly.stackHeight()), false);
keep[0] = true;
for (auto const& returnVariable: _function.returnVariables)
stackLayout.at(m_context->variableStackHeights.at(
keep.at(m_context->variableStackHeights.at(
&std::get<Scope::Variable>(virtualFunctionScope->identifiers.at(returnVariable.name))
)) = true;
// Shuffle leftover arguments up and pop them.
int stackDeficit = 0;
shuffle(stackLayout, [](bool _v) { return _v; }, [&](int _slot) {
auto keepSlot = [](bool _v) { return _v; };
auto swapSlot = [&](int _slot) {
if (m_assembly.stackHeight() - _slot > 17)
stackDeficit = std::max(stackDeficit, m_assembly.stackHeight() - _slot - 17);
else
m_assembly.appendInstruction(evmasm::swapInstruction(
static_cast<unsigned>(m_assembly.stackHeight() - _slot - 1)
));
swap(stackLayout.at(static_cast<size_t>(_slot)), stackLayout.back());
}, [&]() { stackLayout.pop_back(); m_assembly.appendInstruction(evmasm::Instruction::POP); });
swap(keep.at(static_cast<size_t>(_slot)), keep.back());
};
auto popSlot = [&]() {
keep.pop_back();
m_assembly.appendInstruction(evmasm::Instruction::POP);
};
shuffle(keep, keepSlot, swapSlot, popSlot);
if (stackDeficit)
{
@ -775,16 +781,19 @@ void CodeTransform::setupReturnVariablesAndFunctionExit()
availableStackSlots.emplace(height++);
int maxHeight = (*availableStackSlots.crbegin()) + 1;
// Create a mask that is true for return variables and the return label and false for any remaining arguments in between.
// Create a layout that has an increasing integer sequence in place of the return variables.
// Create a layout that has an increasing integer sequence in place of the return variables and
// contains -1 in place of arguments to be popped.
vector<int> layout(static_cast<size_t>(maxHeight), -1);
for (auto&& [n, slot]: ranges::views::enumerate(availableStackSlots))
layout.at(static_cast<size_t>(slot)) = static_cast<int>(n + 1);
layout[0] = 0;
shuffle(layout, [](auto const& _v) { return _v != -1; }, [&](int slot) {
auto keepSlot = [](auto const& _v) { return _v != -1; };
auto swapSlot = [&](int slot) {
swap(layout.at(static_cast<size_t>(slot)), layout.back());
}, [&]() { layout.pop_back(); });
};
auto popSlot = [&]() { layout.pop_back(); };
shuffle(layout, keepSlot, swapSlot, popSlot);
yulAssert(layout.size() == m_delayedReturnVariables.size() + 1, "");