[PATCH] D86414: [compiler-rt][builtins] Fix some other cases of UB

[Anatoly Trosinenko via Phabricator via cfe-commits]

atrosinenko created this revision.
atrosinenko added reviewers: scanon, koviankevin, MaskRay, howard.hinnant.
Herald added subscribers: Sanitizers, dberris.
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atrosinenko requested review of this revision.

This patch eliminates some other UB in a slightly more tricky way than D86299: [compiler-rt][builtins] Factor out some common bit manipulations <https://reviews.llvm.org/D86299>.

- Introduce a `SIGN_OF(signed_int)` macro (not UB-related, just to give this trick a descriptive name)
- Make the "negate if sign is -1" trick operate on corresponding **unsigned** types. Not factoring it out due to the "interface" of that macro would probably be quite error-prone.

This patch is expected to be NFC except for eliminating some UB identified by unit tests.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D86414

Files:
  compiler-rt/lib/builtins/absvdi2.c
  compiler-rt/lib/builtins/absvsi2.c
  compiler-rt/lib/builtins/absvti2.c
  compiler-rt/lib/builtins/floattidf.c
  compiler-rt/lib/builtins/floattixf.c
  compiler-rt/lib/builtins/int_div_impl.inc
  compiler-rt/lib/builtins/int_types.h

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