Displaying 1 result from an estimated 1 matches for "fib34".
2016 Jun 10
2
MCJIT -- Poor run-time performance for Fibonacci example in LLVM 3.8.1
We have been using LLVM 3.4 and are currently migrating to LLVM 3.8.1. We have been using the Old JIT and since it has been removed since 3.6, we have to use MCJIT. I find that run-time performance is very poor in 3.8.1 for the Fibonacci example in llvm/examples/fibonacci.cpp. Logs below for fib34 and fib381 for input values of 30 and 40. I first thought it could be that MCJIT compile time is slower, but as I increase the input value, fib381 gets slower and slower in run-time performance (almost 200X for an input value of 40). Any hints on what could be going wrong? TIA.
% time fib34 30
......