Tachyon counts elided path nodes instead of elided stacks

[pablogsal]

Bug report

Bug description:

elided_count is the number of missing path prefixes, not the number of removed stacks.

import time

def old_leaf():
    time.sleep(1)

def old_mid():
    old_leaf()

def main():
    old_mid()  # replace this with time.sleep(1) for the current run

main()

Create a binary baseline, make the indicated edit, then generate a differential flamegraph. One removed stack (old_mid -> old_leaf) is reported as two elided stacks.

Very small removed paths can also be counted and then removed by the 0.1% rendering filter, leaving a positive count with no elided graph to display.

CPython versions tested on:

3.16

Operating systems tested on:

Linux

Linked PRs

• gh-154088: Count elided stacks consistently #154093
• [3.15] gh-154088: Count elided stacks consistently (GH-154093) #156386