Gat normalization rework

[compiler-errors]

This commit history is an absolute disaster. Putting this up because I want a perf test!

r? @ghost

[joshtriplett]

@bors try @rust-timer queue

[rust-timer]

Awaiting bors try build completion.

@rustbot label: +S-waiting-on-perf

[bors]

⌛ Trying commit 82d1882 with merge 8681ff519be30cff5621d3862567b09a2c4ada1b...

[bors]

☀️ Try build successful - checks-actions
Build commit: 8681ff519be30cff5621d3862567b09a2c4ada1b (8681ff519be30cff5621d3862567b09a2c4ada1b)

[rust-timer]

Queued 8681ff519be30cff5621d3862567b09a2c4ada1b with parent 393fdc1, future comparison URL.

[rust-timer]

Finished benchmarking commit (8681ff519be30cff5621d3862567b09a2c4ada1b): comparison url.

Summary: This benchmark run did not return any relevant results. 17 results were found to be statistically significant but too small to be relevant.

If you disagree with this performance assessment, please file an issue in rust-lang/rustc-perf.

Benchmarking this pull request likely means that it is perf-sensitive, so we're automatically marking it as not fit for rolling up. While you can manually mark this PR as fit for rollup, we strongly recommend not doing so since this PR led to changes in compiler perf.

@bors rollup=never
@rustbot label: +S-waiting-on-review -S-waiting-on-perf -perf-regression

[compiler-errors]

Closing in favor of opening a cleaner PR