Enhance fix of PR17631

[Michael Liao]

Hi All,

It's turned out that a previous fix to PR17631 is not enough to cover
cases where 'CALL' need special handling for 'vzeroupper' insertion. In
addition to helper calls added in prolog, helper calls (not following
any well-defined calling convention) may be also inserted other places,
such as '_ftol2' for double-to-i64 conversion in Windows. The attached
patch enhances the previous fix by checking if the call will clobber any
YMM registers after checking that 'call' won't touch YMMs. It will cover
the cases where isel-lower inserts helper calls not following standard
calling convention.

Thanks for review
- Michael

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