Support diff mode

[lu-zero]

perl flamegraph has a mode to generate diff graphs, it would be useful to have it.

[dabreegster]

jonhoo/inferno#62 is marked done -- I'm curious what's needed here to support diffs?

(Awesome tool by the way, thanks for building it!)

[djc]

Yes, inferno supports this. It's not obvious to me that this fits in well with the flamegraph CLI UX, but feel free to make a proposal for how the CLI should look for this and we can discuss it.

[zz85]

@dabreegster

it probably wasn't clear from that linked issue, but the code in the PR or even running inferno-diff-folded --help explains how to use.

  $ inferno-diff-folded folded1 folded2 | inferno-flamegraph > diff2.svg