commit 53836e2aa0d48411e9853d2e62246e13a59b0994
author Matt Stark <msta@google.com> Thu Aug 28 05:59:13 2025
committer LUCI CQ <infra-scoped@luci-project-accounts.iam.gserviceaccount.com> Thu Aug 28 05:59:13 2025
tree 88d007f57ad600ef6be501242628387e8b61d564
parent e37bb3a75bdb334f78f2a0bd015ce8a7c2c71905

Cut 2.7 seconds off building the graph in siso.

Profiling revealed that 20% of CPU time was spent specifically on growslice calls from pathParser.pathList.

Before:
```
 ~/chromium/src$ hyperfine --warmup=1 -i --runs=10 '/tmp/siso_before ninja -batch=false -C out/no-modules chrome'
Benchmark 1: /tmp/siso_before ninja -batch=false -C out/no-modules chrome
  Time (mean ± σ):      8.665 s ±  0.878 s    [User: 38.652 s, System: 124.206 s]
  Range (min … max):    7.448 s … 10.515 s    10 runs
```

After:

```
~/chromium/src$ hyperfine --warmup=1 -i --runs=10 '~/infra/infra/go/src/infra/build/siso/siso ninja -batch=false -C out/no-modules chrome'
Benchmark 1: ~/infra/infra/go/src/infra/build/siso/siso ninja -batch=false -C out/no-modules chrome
  Time (mean ± σ):      5.958 s ±  0.243 s    [User: 33.402 s, System: 34.875 s]
  Range (min … max):    5.649 s …  6.524 s    10 runs
```

Change-Id: I05a1d4268b291c615141c3778a3030982cc57635
Reviewed-on: https://chromium-review.googlesource.com/c/build/+/6887752
Reviewed-by: Fumitoshi Ukai <ukai@google.com>
Commit-Queue: Matt Stark <msta@google.com>