Code size regression due to improved std::sort

[hiraditya]

Introsort was added to std::sort in https://reviews.llvm.org/D113413. There was a code size regression reported by @smeenai

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I'm working on upgrading Meta's Android apps from libc++ 13 to libc++ 15, and seeing large size regressions caused by this change (similar to the Chrome case above). Was there any progress on figuring out how to offset the binary size increase?
"""

Creating an issue to keep track of this regression.

[hiraditya]

@agrieve also reported a code size regression in Chrome.

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re: binary size - std::sort-related symbols make up more than 1% of Chrome's binary size (for arm32 Android at least). Any work to reduce the size overhead of std::sort() would be very welcome. From what I can tell, the main contributing factor is the templated nature of the function. It gets stamped out a lot of times, and in a way that identical-code-folding is often not applicable.
"""