[llvm-commits] [llvm] r121905 - in /llvm/trunk: lib/Transforms/InstCombine/InstCombineCompares.cpp test/Transforms/InstCombine/overflow.ll

[Duncan Sands]

> Is llvm.sadd.with.overflow implemented on all targets?
> <http://llvm.org/bugs/show_bug.cgi?id=4917#c5><http://llvm.org/bugs/show_bug.cgi?id=4917#c5>http://llvm.org/bugs/show_bug.cgi?id=4917#c5
> suggests that there are problems with mul+overflow, do we legalize add+overflow
> intrinsics for targets that don't support them?

IIRC the problem is with type legalization, for example if you do a 128 bit
mul+overflow it needs to be expanded into 64 bit code.  There's a PR about
this.

Ciao, Duncan.