Hum, benchmark results don't seem good. There is probably a performance bug somewhere. I should investigate further to analyze these results. M aybe combined with the issue #29465, results will be better.

haypo@speed-python$ python3 -m perf compare_to ~/benchmarks/2017-02-06_07-15-default-e06af4027546.json fastcall-no-keywords_ref_e06af4027546.json -G --min-speed=5

Slower (19):
- unpickle_list: 6.36 us +- 0.11 us -> 8.08 us +- 0.14 us: 1.27x slower (+27%)
- pickle_list: 7.53 us +- 0.41 us -> 8.62 us +- 0.49 us: 1.14x slower (+14%)
- crypto_pyaes: 199 ms +- 2 ms -> 226 ms +- 2 ms: 1.13x slower (+13%)
- pickle: 22.1 us +- 0.3 us -> 24.9 us +- 0.3 us: 1.12x slower (+12%)
- nbody: 233 ms +- 2 ms -> 260 ms +- 2 ms: 1.12x slower (+12%)
- xml_etree_iterparse: 179 ms +- 4 ms -> 198 ms +- 5 ms: 1.11x slower (+11%)
- telco: 14.7 ms +- 0.3 ms -> 16.3 ms +- 0.5 ms: 1.11x slower (+11%)
- pickle_dict: 56.6 us +- 4.3 us -> 62.7 us +- 4.7 us: 1.11x slower (+11%)
- pidigits: 291 ms +- 1 ms -> 319 ms +- 1 ms: 1.10x slower (+10%)
- scimark_fft: 662 ms +- 10 ms -> 717 ms +- 8 ms: 1.08x slower (+8%)
- scimark_monte_carlo: 207 ms +- 4 ms -> 224 ms +- 6 ms: 1.08x slower (+8%)
- regex_v8: 43.7 ms +- 0.6 ms -> 47.0 ms +- 0.3 ms: 1.08x slower (+8%)
- float: 238 ms +- 3 ms -> 254 ms +- 4 ms: 1.07x slower (+7%)
- xml_etree_parse: 242 ms +- 5 ms -> 257 ms +- 9 ms: 1.06x slower (+6%)
- raytrace: 1.04 sec +- 0.01 sec -> 1.11 sec +- 0.01 sec: 1.06x slower (+6%)
- unpickle: 30.0 us +- 0.3 us -> 31.8 us +- 0.3 us: 1.06x slower (+6%)
- go: 493 ms +- 7 ms -> 520 ms +- 6 ms: 1.05x slower (+5%)
- scimark_sparse_mat_mult: 8.24 ms +- 0.14 ms -> 8.69 ms +- 0.14 ms: 1.05x slower (+5%)
- chaos: 234 ms +- 2 ms -> 246 ms +- 4 ms: 1.05x slower (+5%)

Faster (2):
- chameleon: 21.9 ms +- 0.2 ms -> 20.7 ms +- 0.3 ms: 1.06x faster (-5%)
- sympy_expand: 949 ms +- 12 ms -> 899 ms +- 11 ms: 1.06x faster (-5%)

Benchmark hidden because not significant (43): (...)