RGBCube/serenity
1
Fork 0
mirror of https://github.com/RGBCube/serenity synced 2025-05-31 21:48:13 +00:00
Code Issues Activity Actions

LibJS: Don't memcpy NewBigInt instruction

Browse source 
These aren't trivially copyable, so we have to be a bit more careful
This commit is contained in:
Hendiadyoin1 2022-10-30 12:24:22 +01:00 • committed by Andreas Kling
parent a1f1d9e4a7
commit 1ac1a5bd58
1 changed files with 12 additions and 4 deletions
Download patch file Download diff file Expand all files Collapse all files

16
Userland/Libraries/LibJS/Bytecode/Pass/MergeBlocks.cpp
View file

@ -142,16 +142,24 @@ void MergeBlocks::perform(PassPipelineExecutable& executable)
for (size_t i = 0; i < successors.size(); ++i) {
auto& entry = successors[i];
InstructionStreamIterator it { entry->instruction_stream() };
size_t copy_end = 0;
while (!it.at_end()) {
auto& instruction = *it;
++it;
if (instruction.is_terminator() && last_successor_index != i)
break;
copy_end = it.offset();
// FIXME: Op::NewBigInt is not trivially copyable, so we cant use
// a simple memcpy to transfer them.
// When this is resolved we can use a single memcpy to copy
// the whole block at once
if (instruction.type() == Instruction::Type::NewBigInt) {
new (block.next_slot()) Op::NewBigInt(static_cast<Op::NewBigInt const&>(instruction));
block.grow(sizeof(Op::NewBigInt));
} else {
auto instruction_size = instruction.length();
memcpy(block.next_slot(), &instruction, instruction_size);
block.grow(instruction_size);
}
}
__builtin_memcpy(block.next_slot(), entry->instruction_stream().data(), copy_end);
block.grow(copy_end);
}
executable.executable.basic_blocks.insert(*first_successor_position, move(new_block));