g++ optimizer report?
John (Eljay) Love-Jensen
Wed Feb 3 13:47:00 GMT 2010
You can get a list of toggle-able optimization flags like this:
gcc -O2 -fverbose-asm -S Empty.cpp -o O2.s
gcc -O3 -fverbose-asm -S Empty.cpp -o O3.s
However, that will not tell you what non-toggle-able optimizations are enabled, since -O2 enables many optimizations that are not controlled by command line flags. And -O3 enables a few more, as I understand it.
Nor will that tell you what optimization(s) were applied to a particular code segment.
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