[bytecode verifer] Adjust metering to decrease runtime of some tests. (…

…#62)

Specifically the test below now runs in 1/2 of the time. This adjustment appeard useful because the overall time allocation had to be increased to 8000 million units in production. Adjusted this as the default here too.

```
--> test_merge_state: verification time: 59.414ms, result: CONSTRAINT_NOT_SATISFIED, size: 63kb
```

Also adjusts the default to what aptos uses now in production.

language/move-bytecode-verifier/bytecode-verifier-tests/src/unit_tests/mod.rs

@@ -47,7 +47,7 @@ pub(crate) fn production_config() -> VerifierConfig {
         max_back_edges_per_module: None,
 
         // Same as the default.
-        max_per_fun_meter_units: Some(1000 * 5000),
-        max_per_mod_meter_units: Some(1000 * 5000),
+        max_per_fun_meter_units: Some(1000 * 8000),
+        max_per_mod_meter_units: Some(1000 * 8000),
     }
 }

language/move-bytecode-verifier/src/reference_safety/abstract_state.rs

@@ -73,7 +73,7 @@ impl std::fmt::Display for Label {
 }
 
 pub(crate) const STEP_BASE_COST: u128 = 10;
-pub(crate) const STEP_PER_LOCAL_COST: u128 = 10;
+pub(crate) const STEP_PER_LOCAL_COST: u128 = 20;
 pub(crate) const STEP_PER_GRAPH_ITEM_COST: u128 = 50;
 pub(crate) const JOIN_BASE_COST: u128 = 100;
 pub(crate) const JOIN_PER_LOCAL_COST: u128 = 10;

language/move-bytecode-verifier/src/verifier.rs

@@ -186,8 +186,8 @@ impl Default for VerifierConfig {
             max_basic_blocks_in_script: None,
             /// General metering for the verifier. This defaults to a bound which should align
             /// with production, so all existing test cases apply it.
-            max_per_fun_meter_units: Some(1000 * 5000),
-            max_per_mod_meter_units: Some(1000 * 5000),
+            max_per_fun_meter_units: Some(1000 * 8000),
+            max_per_mod_meter_units: Some(1000 * 8000),
         }
     }
 }