Since the last update of C ++ Dev, many things have happened in the machine room which were not really visible outside. This message wants to give an overview of what we are currently working on.
In addition to the features, Bob has worked on a process proposed for the re-reception of the C ++ execution client code to Apache 2.0, as mentioned a few times during the month or two. Expect more news on this very soon.
ETH ETH MODE
Not only because it is essential to be able to carry out our solidity of solidity via IPC, Dimitry Khoklov and others added new RPC ending points to the ETH customer which allow much more flexibility to test smart contracts. If you use ETH -Test -D /TMP /Test and connect to the IPC port at /tmp/test/geth.ipc (we recommend that you use Ethereum-Console For this because he already has these added features), you can:
- Modify the blockchain settings (for example, delete proof of the verification of the work and pre-found some accounts)
- mine a certain amount of blocks (about 30 blocks per second)
- Modify the time timeing of the current block (for example test deadlines in your contracts)
- Return the blockchain to a given block number
This allows us to perform our 305 end -to -end tests currently solidity in about 46 seconds on a moderate computer. Each of these tests includes at least two (often more) transactions and the same amount of extracted blocks.
More information on these features can be found to https://github.com/ethereum/ethereum-console.
Please note that it is currently only available for the binary which is provided via the Ubuntu Dev PPA.
Acceleration of the virtual machine
Greg Colvin has spent the last months accelerating the C ++ implementation of the Interpreter EVM. He harvested what he calls low -struggles (he worked for Oracle on the interpreter Java before …). Until now, the most important improvements have been to replace the 256 -bit calculations with 64 -bit calculations for gas measurement, and to ensure that no measurement calculation is carried out for each VM operation as necessary. These changes and others resulted in the following results for the birth of Paweł bylica Reference Suite. The following graph shows the acceleration compared to the former interpreter CPP Ethereum (CPP INT (Old)).
To be fair, we have to say what these benchmarks measure. The first reference (where the EVMJIT comes out of the scale with an acceleration of 472x) makes a million empty loops, and shows how slow the Goto of the EVM is slow to the direct jump of a JIT – a fixation which is the next on the battery. The second reference is a bad generator of random numbers which makes a million loops with four multiplications and four additions per loop. It is dominated by 256 -bit calculations, so a Jit made less difference. (Note that Go Jit does not compile with the native code, but to a faster interpreted representation.)
In practiceThese accelerations only Be relevant for “numbers of numbers” because the calculation time is also largely dominated by access to storage. On the other hand, the “RNG” reference is quite similar to cryptographic operations which attracts such things in the field of real implementations on the chain.
Paweł bylica works on a C language interface Between the implementation of the virtual machine and the client who hosts it, in order to be able to connect different virtual machines to an Ethereum client. In this way, Geth can also benefit from our modifications to the C ++ virtual machine and in particular the LLVM compiler just in time.
Note that these changes are not yet released, but they are part of the Ubuntu Dev PPA.
Remix
Yann Levreau and Liana Husikyan work on our new remix of debugger EVM. We published the Alpha version a few days ago:
Application – Instructions
For the moment, you can “only” use it to inspect each step in the execution of any transaction in the blockchain, consult the current battery, memory and storage content and see the sequence of the instructions. The next step will also be to allow debugging at the source where you can see the current position in the source code, online step or level of education and see the decoded values of the variables (instead of the gross hexadecimal values).
The debugger is for you, the community, and we have been delighted to hear that Etherscan has already joined the remix in their Blockchain Explorer.
Reorganization of the repository
Bob Summerwill is dedicated to bringing C ++ – Ethereum to his old house, and thus remove the unnecessary and confusing division in several sub -emotions. We make great progress there, one of the first really visible steps was to decouple the solidity test infrastructure from the implementation of the virtual machine. Solidity tests can now be compiled without the virtual machine and are executed by contacting a specially configured ETH process (the one mentioned above) on the ordinary IPC interface.
The following steps here are to disentangle the rest of the code, modify the automation of the test and continuous integration accordingly and to carry out the real movement.
With this stage, we unfortunately have to Say goodbye to mix and Alethzero (Mix’s spirit will live in the new Remix project). The burden they drag would be too big, because it includes QT and a tight coupling with solidity. As already explained in the previous articles, a loose coupling based on IPC of these tools to an implementation of a small customer makes us much more flexible and the community support which is accompanied by a change for JavaScript and web tools like remix and solidity of the browser is just crushing in comparison.
Formal verification
We extend the existing formal verification tools integrated into the solidity to transversal calls. This would allow automated evidence that a recursive call attack is not possible against a certain contract. In addition, like Why3 (the tool we use to do heavy work) has recently been worn navigatorsWe can probably expect it to be available just inside the solidity of the browser and other tools such as blockchain explorers!
There is a first proof of concept Including explanations that show how automated verification can be used to show that it is impossible to steal money from a solidity contract, even if recursive calls are authorized.
We hope that this proof of concept will evolve in a tool that can be used in the coming weeks.
Several people from the community and the interior of the Foundation are currently working on solidity or EVM tools in general. These include:
- AST solidity analysis for Dave Hoover’s warnings (@Redsquirrel)
- A Read-Eval version of Solidey by Raineorshine: Solide-repl
- Control flow analysis graph Also by Raineorshine
- EVM disassembly by Nick Johnson
