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Also as your code changes. It's often not that hard to hand-write a single function a bit better than the compiler. But when you want to make a small change th

Also as your code changes. It's often not that hard to hand-write a single function a bit better than the compiler. But when you want to make a small change the compiler will rethink the whole function from scratch, and if you want to keep your advantage you may have to do the same.

acdha 9y ago
That's a very important point: this is especially the case when, say, a data structure grows and clever packing or alignment tricks can no longer be used. I certainly remember that being used as an excuse to delay a change because it was much harder to update some complex optimizations — and at least one case where the original developer tested the generic .c file they'd used to develop the algorithm with a current compiler and found it was faster on the latest hardware we were buying.