JIT

GH-126910: reserve FP on AArch64 when generating JIT stencils #5721

Job	Run time
x86_64-apple-darwin/clang (Debug)	29m 9s
i686-pc-windows-msvc/msvc (Release)	15m 13s
JIT without optimizations (Debug)	3m 37s
Free-Threaded (Debug)	3m 41s
aarch64-apple-darwin/clang (Release)	15m 2s
x86_64-pc-windows-msvc/msvc (Release)	15m 40s
i686-pc-windows-msvc/msvc (Debug)	28m 57s
Interpreter (Debug)	11m 46s
aarch64-apple-darwin/clang (Debug)	14m 17s
JIT with tail calling interpreter	4m 28s
x86_64-apple-darwin/clang (Release)	26m 20s
x86_64-unknown-linux-gnu/gcc (Debug)	14m 17s
aarch64-unknown-linux-gnu/gcc (Debug)	9m 14s
aarch64-unknown-linux-gnu/gcc (Release)	6m 47s
aarch64-pc-windows-msvc/msvc (Debug)	25m 41s
x86_64-pc-windows-msvc/msvc (Debug)	28m 27s
aarch64-pc-windows-msvc/msvc (Release)	18m 47s
x86_64-unknown-linux-gnu/gcc (Release)	8m 44s
	4h 40m 7s

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