Fix CantWriteReturnFp and other issues related to the initial gas loading

[FrancoGiachetta]

TITLE

Description

This PR solves an issue which was generated due to how we are loading the initial gas. Instead of doing it by executing an instruction, it is done in the rust side, updating the ap "by hand". Even though this is correct, there are other instructions like this one which rely on how many variables have already been allocated until that point to generate the correct instruction (it calls this method). Since there is no knowledge that the initial gas has been loaded, the casm builder does not take it into account and, thus, its variable counter is 1 unit behind the correct amount of current variables. This leads to instructions trying to access to memory cells which have already been written.

Refers to: #2011

Checklist

• Linked to Github Issue
• Unit tests added
• Integration tests added.
• This change requires new documentation.
  • Documentation has been added/updated.
  • CHANGELOG has been updated.

[github-actions]

**Hyper Thereading Benchmark results**




hyperfine -r 2 -n "hyper_threading_main threads: 1" 'RAYON_NUM_THREADS=1 ./hyper_threading_main' -n "hyper_threading_pr threads: 1" 'RAYON_NUM_THREADS=1 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 1
  Time (mean ± σ):     26.679 s ±  0.013 s    [User: 25.807 s, System: 0.870 s]
  Range (min … max):   26.670 s … 26.688 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 1
  Time (mean ± σ):     26.568 s ±  0.053 s    [User: 25.728 s, System: 0.838 s]
  Range (min … max):   26.531 s … 26.606 s    2 runs
 
Summary
  hyper_threading_pr threads: 1 ran
    1.00 ± 0.00 times faster than hyper_threading_main threads: 1




hyperfine -r 2 -n "hyper_threading_main threads: 2" 'RAYON_NUM_THREADS=2 ./hyper_threading_main' -n "hyper_threading_pr threads: 2" 'RAYON_NUM_THREADS=2 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 2
  Time (mean ± σ):     14.787 s ±  0.007 s    [User: 25.757 s, System: 0.906 s]
  Range (min … max):   14.781 s … 14.792 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 2
  Time (mean ± σ):     14.776 s ±  0.019 s    [User: 25.753 s, System: 0.897 s]
  Range (min … max):   14.763 s … 14.790 s    2 runs
 
Summary
  hyper_threading_pr threads: 2 ran
    1.00 ± 0.00 times faster than hyper_threading_main threads: 2




hyperfine -r 2 -n "hyper_threading_main threads: 4" 'RAYON_NUM_THREADS=4 ./hyper_threading_main' -n "hyper_threading_pr threads: 4" 'RAYON_NUM_THREADS=4 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 4
  Time (mean ± σ):     11.018 s ±  0.076 s    [User: 37.927 s, System: 1.007 s]
  Range (min … max):   10.964 s … 11.071 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 4
  Time (mean ± σ):     10.623 s ±  0.126 s    [User: 37.596 s, System: 1.030 s]
  Range (min … max):   10.534 s … 10.712 s    2 runs
 
Summary
  hyper_threading_pr threads: 4 ran
    1.04 ± 0.01 times faster than hyper_threading_main threads: 4




hyperfine -r 2 -n "hyper_threading_main threads: 6" 'RAYON_NUM_THREADS=6 ./hyper_threading_main' -n "hyper_threading_pr threads: 6" 'RAYON_NUM_THREADS=6 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 6
  Time (mean ± σ):     10.547 s ±  0.012 s    [User: 38.275 s, System: 1.044 s]
  Range (min … max):   10.539 s … 10.555 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 6
  Time (mean ± σ):     10.659 s ±  0.125 s    [User: 38.039 s, System: 1.053 s]
  Range (min … max):   10.571 s … 10.747 s    2 runs
 
Summary
  hyper_threading_main threads: 6 ran
    1.01 ± 0.01 times faster than hyper_threading_pr threads: 6




hyperfine -r 2 -n "hyper_threading_main threads: 8" 'RAYON_NUM_THREADS=8 ./hyper_threading_main' -n "hyper_threading_pr threads: 8" 'RAYON_NUM_THREADS=8 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 8
  Time (mean ± σ):     10.416 s ±  0.152 s    [User: 38.336 s, System: 1.054 s]
  Range (min … max):   10.308 s … 10.523 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 8
  Time (mean ± σ):     10.253 s ±  0.014 s    [User: 38.826 s, System: 1.067 s]
  Range (min … max):   10.244 s … 10.263 s    2 runs
 
Summary
  hyper_threading_pr threads: 8 ran
    1.02 ± 0.01 times faster than hyper_threading_main threads: 8




hyperfine -r 2 -n "hyper_threading_main threads: 16" 'RAYON_NUM_THREADS=16 ./hyper_threading_main' -n "hyper_threading_pr threads: 16" 'RAYON_NUM_THREADS=16 ./hyper_threading_pr'
Benchmark 1: hyper_threading_main threads: 16
  Time (mean ± σ):     10.496 s ±  0.159 s    [User: 38.588 s, System: 1.201 s]
  Range (min … max):   10.384 s … 10.608 s    2 runs
 
Benchmark 2: hyper_threading_pr threads: 16
  Time (mean ± σ):     10.293 s ±  0.097 s    [User: 38.772 s, System: 1.169 s]
  Range (min … max):   10.225 s … 10.361 s    2 runs
 
Summary
  hyper_threading_pr threads: 16 ran
    1.02 ± 0.02 times faster than hyper_threading_main threads: 16

[github-actions]

Benchmark Results for unmodified programs 🚀

Command	Mean [s]	Min [s]	Max [s]	Relative
base big_factorial	2.111 ± 0.011	2.101	2.139	1.00
head big_factorial	2.132 ± 0.013	2.112	2.160	1.01 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base big_fibonacci	2.103 ± 0.050	2.033	2.156	1.03 ± 0.03
head big_fibonacci	2.051 ± 0.027	2.028	2.099	1.00

Command	Mean [s]	Min [s]	Max [s]	Relative
base blake2s_integration_benchmark	7.633 ± 0.157	7.470	7.920	1.00
head blake2s_integration_benchmark	7.744 ± 0.139	7.501	7.987	1.01 ± 0.03

Command	Mean [s]	Min [s]	Max [s]	Relative
base compare_arrays_200000	2.163 ± 0.011	2.153	2.187	1.00
head compare_arrays_200000	2.232 ± 0.063	2.164	2.350	1.03 ± 0.03

Command	Mean [s]	Min [s]	Max [s]	Relative
base dict_integration_benchmark	1.483 ± 0.021	1.457	1.530	1.00
head dict_integration_benchmark	1.532 ± 0.039	1.476	1.588	1.03 ± 0.03

Command	Mean [s]	Min [s]	Max [s]	Relative
base field_arithmetic_get_square_benchmark	1.245 ± 0.007	1.237	1.265	1.01 ± 0.01
head field_arithmetic_get_square_benchmark	1.238 ± 0.010	1.226	1.254	1.00

Command	Mean [s]	Min [s]	Max [s]	Relative
base integration_builtins	7.793 ± 0.238	7.583	8.208	1.01 ± 0.03
head integration_builtins	7.733 ± 0.124	7.615	8.015	1.00

Command	Mean [s]	Min [s]	Max [s]	Relative
base keccak_integration_benchmark	7.896 ± 0.065	7.797	8.021	1.00
head keccak_integration_benchmark	7.997 ± 0.108	7.878	8.229	1.01 ± 0.02

Command	Mean [s]	Min [s]	Max [s]	Relative
base linear_search	2.208 ± 0.051	2.156	2.291	1.03 ± 0.03
head linear_search	2.142 ± 0.018	2.125	2.189	1.00

Command	Mean [s]	Min [s]	Max [s]	Relative
base math_cmp_and_pow_integration_benchmark	1.514 ± 0.014	1.493	1.543	1.00
head math_cmp_and_pow_integration_benchmark	1.519 ± 0.011	1.504	1.545	1.00 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base math_integration_benchmark	1.451 ± 0.009	1.442	1.468	1.00
head math_integration_benchmark	1.455 ± 0.005	1.450	1.468	1.00 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base memory_integration_benchmark	1.215 ± 0.006	1.210	1.228	1.00
head memory_integration_benchmark	1.233 ± 0.012	1.217	1.250	1.01 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base operations_with_data_structures_benchmarks	1.581 ± 0.020	1.556	1.613	1.01 ± 0.01
head operations_with_data_structures_benchmarks	1.562 ± 0.004	1.556	1.569	1.00

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
base pedersen	534.3 ± 3.7	530.9	541.6	1.00 ± 0.01
head pedersen	532.0 ± 1.1	530.6	533.6	1.00

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
base poseidon_integration_benchmark	637.2 ± 6.2	631.1	649.1	1.00
head poseidon_integration_benchmark	650.0 ± 6.7	642.7	666.2	1.02 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base secp_integration_benchmark	1.842 ± 0.011	1.830	1.870	1.00
head secp_integration_benchmark	1.849 ± 0.008	1.840	1.867	1.00 ± 0.01

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
base set_integration_benchmark	624.6 ± 2.6	621.0	628.9	1.00
head set_integration_benchmark	628.1 ± 3.3	623.4	634.2	1.01 ± 0.01

Command	Mean [s]	Min [s]	Max [s]	Relative
base uint256_integration_benchmark	4.193 ± 0.027	4.148	4.235	1.00 ± 0.01
head uint256_integration_benchmark	4.183 ± 0.025	4.144	4.221	1.00

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 96.53%. Comparing base (04e5e8d) to head (a4178d9).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #2015   +/-   ##
=======================================
  Coverage   96.53%   96.53%           
=======================================
  Files         102      102           
  Lines       42725    42720    -5     
=======================================
- Hits        41245    41241    -4     
+ Misses       1480     1479    -1     

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