fe92c15f0c script/sign: avoid duplicated signature verification after signing (Sebastian Falbesoner)
080089567c bench: add benchmark for `SignTransaction` (Sebastian Falbesoner)
Pull request description:
This PR is a small performance improvement on the `SignTransaction` function, which is used mostly by the wallet (obviously) and the `signrawtransactionwithkey` RPC. The lower-level function `ProduceSignature` already calls `VerifyScript` internally as last step in order to check whether the signature data is complete:
daa56f7f66/src/script/sign.cpp (L568-L570)
If and only if that is the case, the `complete` field of the `SignatureData` is set to `true` accordingly and there is no need then to verify the script after again, as we already know that it would succeed.
This leads to a rough ~20% speed-up for `SignTransaction` for single-input ECDSA or Taproot transactions, according to the newly introduced `SignTransaction{ECDSA,Taproot}` benchmarks:
```
$ ./src/bench/bench_bitcoin --filter=SignTransaction.*
```
without commit 18185f4f578b8795fdaa75926630a691e9c8d0d4:
| ns/op | op/s | err% | total | benchmark
|--------------------:|--------------------:|--------:|----------:|:----------
| 185,597.79 | 5,388.00 | 1.6% | 0.22 | `SignTransactionECDSA`
| 141,323.95 | 7,075.94 | 2.1% | 0.17 | `SignTransactionSchnorr`
with commit 18185f4f578b8795fdaa75926630a691e9c8d0d4:
| ns/op | op/s | err% | total | benchmark
|--------------------:|--------------------:|--------:|----------:|:----------
| 149,757.86 | 6,677.45 | 1.4% | 0.18 | `SignTransactionECDSA`
| 108,284.40 | 9,234.94 | 2.0% | 0.13 | `SignTransactionSchnorr`
Note that there are already signing benchmarks in the secp256k1 library, but `SignTransaction` does much more than just the cryptographical parts, i.e.:
* calculate the unsigned tx's `PrecomputedTransactionData` if necessary
* apply Solver on the prevout scriptPubKey, fetch the relevant keys from the signing provider
* perform the actual signing operation (for ECDSA signatures, that could be more than once due to low-R grinding)
* verify if the signatures are correct by calling `VerifyScript` (more than once currently, which is fixed by this PR)
so it probably makes sense to also have benchmarks from that higher-level application perspective.
ACKs for top commit:
achow101:
ACK fe92c15f0c
furszy:
utACK fe92c15f0c
glozow:
light review ACK fe92c15f0c
Tree-SHA512: b7225ff9e8a640ca5222dea5b2a463a0f9b9de704e4330b5b9a7bce2d63a1f4620575c474a8186f4708d7d9534eab55d000393d99db79c0cfc046b35f0a4a778