diff options
| author | Hein-Pieter van Braam <hp@tmm.cx> | 2019-01-09 01:09:56 +0100 |
|---|---|---|
| committer | Hein-Pieter van Braam <hp@tmm.cx> | 2019-01-09 02:06:13 +0100 |
| commit | e5b335d367103f4052fc5fd435a54ad635ec447c (patch) | |
| tree | b08fd5e62c9765f99cddd375c9e7a66f3b6bf17b /platform/iphone | |
| parent | e46f28e02dde08bb515fdd796ffcf114361e4877 (diff) | |
Don't use -ffast-math or other unsafe math optimizations
Godot supports many different compilers and for production releases we
have to support 3 currently: GCC8, Clang6, and MSVC2017. These compilers
all do slightly different things with -ffast-math and it is causing
issues now. See #24841, #24540, #10758, #10070. And probably other
complaints about physics differences between release and release_debug
builds.
I've done some performance comparisons on Linux x86_64. All tests are
ran 20 times.
Bunnymark: (higher is better)
(bunnies) min max stdev average
fast-math 7332 7597 71 7432
this pr 7379 7779 108 7621 (102%)
FPBench (gdscript port http://fpbench.org/) (lower is better)
(ms)
fast-math 15441 16127 192 15764
this pr 15671 16855 326 16001 (99%)
Float_add (adding floats in a tight loop) (lower is better)
(sec)
fast-math 5.49 5.78 0.07 5.65
this pr 5.65 5.90 0.06 5.76 (98%)
Float_div (dividing floats in a tight loop) (lower is better)
(sec)
fast-math 11.70 12.36 0.18 11.99
this pr 11.92 12.32 0.12 12.12 (99%)
Float_mul (multiplying floats in a tight loop) (lower is better)
(sec)
fast-math 11.72 12.17 0.12 11.93
this pr 12.01 12.62 0.17 12.26 (97%)
I have also looked at FPS numbers for tps-demo, 3d platformer, 2d
platformer, and sponza and could not find any measurable difference.
I believe that given the issues and oft-reported (physics) glitches on
release builds I believe that the couple of percent of tight-loop
floating point performance regression is well worth it.
This fixes #24540 and fixes #24841
Diffstat (limited to 'platform/iphone')
| -rw-r--r-- | platform/iphone/detect.py | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/platform/iphone/detect.py b/platform/iphone/detect.py index 20fb4428dd..797a7d31aa 100644 --- a/platform/iphone/detect.py +++ b/platform/iphone/detect.py @@ -46,7 +46,7 @@ def configure(env): if (env["target"].startswith("release")): env.Append(CPPFLAGS=['-DNDEBUG', '-DNS_BLOCK_ASSERTIONS=1']) if (env["optimize"] == "speed"): #optimize for speed (default) - env.Append(CPPFLAGS=['-O2', '-ftree-vectorize', '-fomit-frame-pointer', '-ffast-math', '-funsafe-math-optimizations']) + env.Append(CPPFLAGS=['-O2', '-ftree-vectorize', '-fomit-frame-pointer']) env.Append(LINKFLAGS=['-O2']) else: #optimize for size env.Append(CPPFLAGS=['-Os', '-ftree-vectorize']) |