JIT

gh-142889: Restructure PyDictKeysObject memory layout for simpler access #5339

Job	Run time
Interpreter (Debug)	11m 37s
JIT with tail calling interpreter (21)	4m 25s
Free-Threaded (Debug) (21)	17m 41s
JIT without optimizations (Debug) (21)	13m 30s
x86_64-pc-windows-msvc/msvc (Release)	15m 21s
i686-pc-windows-msvc/msvc (Release)	14m 46s
aarch64-unknown-linux-gnu/gcc (Release)	6m 50s
x86_64-apple-darwin/clang (Debug)	32m 13s
x86_64-apple-darwin/clang (Release)	21m 43s
x86_64-pc-windows-msvc/msvc (Debug)	26m 44s
aarch64-unknown-linux-gnu/gcc (Debug)	8m 16s
i686-pc-windows-msvc/msvc (Debug)	27m 1s
aarch64-pc-windows-msvc/msvc (Debug)	24m 54s
x86_64-unknown-linux-gnu/gcc (Release)	8m 32s
aarch64-pc-windows-msvc/msvc (Release)	18m 14s
aarch64-apple-darwin/clang (Debug)	12m 2s
aarch64-apple-darwin/clang (Release)	10m 31s
x86_64-unknown-linux-gnu/gcc (Debug)	13m 20s
	4h 47m 40s

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