this post was submitted on 09 Oct 2023
247 points (98.8% liked)
Open Source
30511 readers
825 users here now
All about open source! Feel free to ask questions, and share news, and interesting stuff!
Useful Links
- Open Source Initiative
- Free Software Foundation
- Electronic Frontier Foundation
- Software Freedom Conservancy
- It's FOSS
- Android FOSS Apps Megathread
Rules
- Posts must be relevant to the open source ideology
- No NSFW content
- No hate speech, bigotry, etc
Related Communities
- !libre_culture@lemmy.ml
- !libre_software@lemmy.ml
- !libre_hardware@lemmy.ml
- !linux@lemmy.ml
- !technology@lemmy.ml
Community icon from opensource.org, but we are not affiliated with them.
founded 5 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
I have the utmost respect for the ffmpeg developers; writing ASM is a skill I do not possess. I do have to wonder, though, would it be easier for cross-platform compatibility to write in C instead. I have always understood that C generally compiles almost directly to assembly with little to no abstraction overhead, and it would not require platform-specific ASM code. What is the logic in choosing ASM over C? I have no doubt there is a good reason.
The reason is SIMD instructions / vectorized assembly instructions with consideration for delay slots, instruction latency, memory access times etc., for which GCC and Clang optimizers are both terrible and cannot automatically transform C code to them in any but simple cases.
This is also a reason why specialized DSP processors with SIMD capabilities have dedicated proprietary compilers for them.