fix: Use froundeven for lowering float roundings

[maximilianruesch]

Ensures that we use tie-to-even instead of tie-away-from-zero, for more consistency with Pythons round.

[maximilianruesch]

This should be backported to v1.0.X as well, if we can do it (considering dependency constraints)

[github-actions]

Bencher Report

Project	guppylang
Branch	mr/fix/froundeven
Testbed	Linux

Click to view all benchmark results

Benchmark	hugr_bytes	Benchmark Result bytes x 1e3 (Result Δ%)	Upper Boundary bytes x 1e3 (Limit %)	hugr_nodes	Benchmark Result nodes (Result Δ%)	Upper Boundary nodes (Limit %)
tests/benchmarks/test_big_array.py::test_big_array_compile	📈 view plot 🚷 view threshold	62.10 x 1e3 (0.00%) Baseline: 62.10 x 1e3	62.72 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	4,585.00 (0.00%) Baseline: 4,585.00	4,630.85 (99.01%)
tests/benchmarks/test_ctrl_flow.py::test_many_ctrl_flow_compile	📈 view plot 🚷 view threshold	27.80 x 1e3 (0.00%) Baseline: 27.80 x 1e3	28.08 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	1,301.00 (0.00%) Baseline: 1,301.00	1,314.01 (99.01%)
tests/benchmarks/test_queue_push_pop.py::test_queue_push_benchmark_compile	📈 view plot 🚷 view threshold	7.24 x 1e3 (0.00%) Baseline: 7.24 x 1e3	7.32 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	310.00 (0.00%) Baseline: 310.00	313.10 (99.01%)
tests/benchmarks/test_queue_push_pop.py::test_queue_push_pop_benchmark_compile	📈 view plot 🚷 view threshold	9.86 x 1e3 (0.00%) Baseline: 9.86 x 1e3	9.96 x 1e3 (99.01%)	📈 view plot 🚷 view threshold	411.00 (0.00%) Baseline: 411.00	415.11 (99.01%)

🐰 View full continuous benchmarking report in Bencher

[codecov-commenter]

Codecov Report

❌ Patch coverage is 75.00000% with 1 line in your changes missing coverage. Please review.
✅ Project coverage is 93.23%. Comparing base (a46555e) to head (37834a6).

Files with missing lines	Patch %	Lines
guppylang/src/guppylang/std/num.py	75.00%	1 Missing ⚠️

Additional details and impacted files

@@                      Coverage Diff                      @@
##           mr/perf/upgrade-toolchain    #2286      +/-   ##
=============================================================
- Coverage                      93.23%   93.23%   -0.01%     
=============================================================
  Files                            162      162              
  Lines                          15824    15828       +4     
=============================================================
+ Hits                           14754    14757       +3     
- Misses                          1070     1071       +1     

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[codspeed-hq]

Merging this PR will improve performance by 40.31%

⚠️ Different runtime environments detected

Some benchmarks with significant performance changes were compared across different runtime environments,
which may affect the accuracy of the results.

Open the report in CodSpeed to investigate

⚡ 2 improved benchmarks
✅ 9 untouched benchmarks

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
⚡	test_queue_push_pop_benchmark	4.4 s	3.1 s	+40.93%
⚡	test_queue_push_benchmark	3.4 s	2.4 s	+39.69%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing mr/fix/froundeven (37834a6) with main (3560b6e)}

[aborgna-q]

This is fine for backporting, but for guppy 1.1 we should bump it to qis-compiler 0.5

[maximilianruesch]

Yes, that upgrade will be done separately. I have now pulled out the actual dependency upgrades in #2284, so that this PR does not have a perf improvement attached that it should not have.