On Mon, 2014-12-15 at 11:34 -0800, Josh Stone wrote: > On 12/14/2014 02:18 PM, Mark Wielaard wrote: > > This finally adds bounds checking to get_[us]leb128 (with two exceptions, > > see below). The performance results are a little puzzling, so I hope > > Josh can take a look how things are for him. > > > > On one system, with 3.10.0-123.13.1.el7.x86_64, varlocs -k slows down: > > 0.160: 53.65 > > master: 52.24 > > mjw/pending: 56.35 > > > > But on another, with 3.17.4-301.fc21.x86_64, varlocs -k speeds up: > > 0.160: 69.41 > > master: 69.03 > > mjw/pending: 68.29 > > > > Output is the same between versions for each system. > > These are probably different compilers too, right? So I suspect the > newer compiler just noticed an optimization opportunity.
Yes they are. The first is 4.8.2, the second is 4.9.2. If I run the tests with the binary of the second on the first system it is a little faster. From slightly higher than 55 seconds to slightly lower than 53 seconds. So GCC 4.9 does indeed produce a little faster code compared to GCC 4.8. Cheers, Mark
