perf: reduce Result checks in Gasometer

[mooori]

Gasometer has a field inner: Result<Inner<'config>, ExitError>. That
field is often accessed in Gasometer's method record_dynamic_cost, which
involves a lot of ? operators. This was identified as inefficiency in #448 (2nd item).

To improve performance, a mutable reference to Inner is stored in a variable
and used througout record_dynamic_cost, which allows to remove most ? in
that method.

Snapshot::new() is added to avoid ownership issues when compiling with
--features tracing. Gasometer::snapshot() borrows self, which can be
avoided by using Snapshot::new instead.

NEAR gas reductions

Including this in aurora-engine makes the following tests fail due to NEAR gas
usage which is lower than the expected numbers:

tests::one_inch::test_1inch_liquidity_protocol
tests::repro::repro_5bEgfRQ
tests::repro::repro_8ru7VEA
tests::repro::repro_D98vwmi
tests::repro::repro_FRcorNv
tests::repro::repro_GdASJ3KESs
tests::uniswap::test_uniswap_exact_output
tests::uniswap::test_uniswap_input_multihop

Reproduction

tree
.
├── aurora-engine # @ develop branch
├── sputnikvm     # containing this PR's modifications

Patch aurora-engine to include the locally modified sputnikvm:

diff --git a/Cargo.toml b/Cargo.toml
index f27de56..1f4bedf 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -27,6 +27,12 @@ rpath = false
 lto = true
 opt-level = 3
 
+[patch.'https://github.com/aurora-is-near/sputnikvm.git']
+evm = { path = "../sputnikvm" }
+evm-core = { path = "../sputnikvm/core" }
+evm-gasometer = { path = "../sputnikvm/gasometer" }
+evm-runtime = { path = "../sputnikvm/runtime" }
+
 [workspace]
 resolver = "2"
 members = [

Run tests with:

cd aurora-engine
make check

[mfornet]

LGTM.

@joshuajbouw what are the possibilities of adding this generic changes upstream?

[mooori]

The NEAR gas reduction numbers have been missing - posting them here:

---- tests::repro::repro_8ru7VEA stdout ----
thread 'tests::repro::repro_8ru7VEA' panicked at 'assertion failed: `(left == right)`                                 
  left: `242`,                                             
 right: `236`', engine-tests/src/tests/repro.rs:146:5                                                                 
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
                                                                                                                      
---- tests::repro::repro_5bEgfRQ stdout ----
thread 'tests::repro::repro_5bEgfRQ' panicked at 'assertion failed: `(left == right)`                                 
  left: `706`,                                             
 right: `687`', engine-tests/src/tests/repro.rs:146:5
                                                           
---- tests::repro::repro_D98vwmi stdout ----
thread 'tests::repro::repro_D98vwmi' panicked at 'assertion failed: `(left == right)`                                 
  left: `199`,                                             
 right: `194`', engine-tests/src/tests/repro.rs:146:5
                                                           
---- tests::repro::repro_GdASJ3KESs stdout ----                                                                       
thread 'tests::repro::repro_GdASJ3KESs' panicked at 'assertion failed: `(left == right)`                              
  left: `133`,               
 right: `130`', engine-tests/src/tests/repro.rs:146:5                                                                 

---- tests::repro::repro_FRcorNv stdout ----       
thread 'tests::repro::repro_FRcorNv' panicked at 'assertion failed: `(left == right)`
  left: `197`,                                             
 right: `192`', engine-tests/src/tests/repro.rs:146:5   
                                                                                                                      
---- tests::uniswap::test_uniswap_input_multihop stdout ----   
thread 'tests::uniswap::test_uniswap_input_multihop' panicked at 'assertion failed: `(left == right)`                 
  left: `123`,                                                                                                        
 right: `119`', engine-tests/src/tests/uniswap.rs:41:5                                                                
                                                                                                                      
---- tests::one_inch::test_1inch_liquidity_protocol stdout ----       
thread 'tests::one_inch::test_1inch_liquidity_protocol' panicked at '20 Tgas is not equal to 21 Tgas', engine-tests/src/test_utils/mod.rs:842:5                                                                                             

[birchmd]

Merged in 148c6f9 (did not go into master since we have a hard time getting our changes into upstream; but it is included in our internal release https://github.com/aurora-is-near/sputnikvm/releases/tag/v0.37.2-aurora )