JIT

GH-130415: Narrow `str` to `""` based on boolean tests #2842

Job	Run time
Interpreter (Debug)	8m 7s
Free-Threaded (Debug) (19)	14m 2s
i686-pc-windows-msvc/msvc (Debug)	18m 29s
i686-pc-windows-msvc/msvc (Release)	12m 7s
x86_64-pc-windows-msvc/msvc (Debug)	16m 49s
x86_64-pc-windows-msvc/msvc (Release)	11m 12s
aarch64-pc-windows-msvc/msvc (Debug)	5m 1s
aarch64-pc-windows-msvc/msvc (Release)	5m 18s
x86_64-apple-darwin/clang (Debug)	15m 4s
x86_64-apple-darwin/clang (Release)	11m 4s
aarch64-apple-darwin/clang (Debug)	10m 36s
aarch64-apple-darwin/clang (Release)	11m 39s
x86_64-unknown-linux-gnu/gcc (Debug)	9m 43s
x86_64-unknown-linux-gnu/gcc (Release)	5m 46s
aarch64-unknown-linux-gnu/gcc (Debug)	9m 18s
aarch64-unknown-linux-gnu/gcc (Release)	6m 25s
	2h 50m 40s

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