Top "Compiler-optimization" questions

Compiler optimization involves adapting a compiler to reduce run-time or object size or both.

Why do we use volatile keyword?

Possible Duplicate: C++: When Has The volatile Keyword Ever Helped You? I have never used it but I wonder why …

c++ volatile compiler-optimization
How to compile Tensorflow with SSE4.2 and AVX instructions?

This is the message received from running a script to check if Tensorflow is working: I tensorflow/stream_executor/dso_…

tensorflow x86 compiler-optimization simd compiler-options
Why are elementwise additions much faster in separate loops than in a combined loop?

Suppose a1, b1, c1, and d1 point to heap memory and my numerical code has the following core loop. const …

c++ performance x86 vectorization compiler-optimization
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?

I am doing some numerical optimization on a scientific application. One thing I noticed is that GCC will optimize the …

gcc assembly floating-point compiler-optimization fast-math
Replacing a 32-bit loop counter with 64-bit introduces crazy performance deviations with _mm_popcnt_u64 on Intel CPUs

I was looking for the fastest way to popcount large arrays of data. I encountered a very weird effect: Changing …

c++ performance assembly x86 compiler-optimization
Swift Beta performance: sorting arrays

I was implementing an algorithm in Swift Beta and noticed that the performance was very poor. After digging deeper I …

swift performance sorting xcode6 compiler-optimization
How to turn off gcc compiler optimization to enable buffer overflow

I'm working on a homework problem that requires disabling compiler optimization protection for it to work. I'm using gcc 4.4.1 on …

c gcc buffer-overflow compiler-optimization
How to disable compiler optimizations in gcc?

I am trying to learn assembly language. I have searched and found how to disassemble a .c file but I …

c gcc compiler-optimization compiler-options
How to see which flags -march=native will activate?

I'm compiling my C++ app using GCC 4.3. Instead of manually selecting the optimization flags I'm using -march=native, which in …

gcc g++ compiler-optimization compiler-flags
Why does GCC generate 15-20% faster code if I optimize for size instead of speed?

I first noticed in 2009 that GCC (at least on my projects and on my machines) have the tendency to generate …

c++ performance gcc x86-64 compiler-optimization