This revision was automatically updated to reflect the committed changes.
Closed by commit rC333038: [CodeGen] use nsw negation for builtin abs (authored
by spatel, committed by ).
Repository:
rC Clang
https://reviews.llvm.org/D47202
Files:
lib/CodeGen/CGBuiltin.cpp
test/CodeGen/builtin-a
This revision was automatically updated to reflect the committed changes.
Closed by commit rL333038: [CodeGen] use nsw negation for builtin abs (authored
by spatel, committed by ).
Herald added a subscriber: llvm-commits.
Changed prior to commit:
https://reviews.llvm.org/D47202?vs=148020&id=148
craig.topper accepted this revision.
craig.topper added a comment.
This revision is now accepted and ready to land.
This seems right to me. GCC believes believes that __bultin_abs always returns
a positive number.
https://reviews.llvm.org/D47202
__
spatel added a comment.
In https://reviews.llvm.org/D47202#1108016, @lebedev.ri wrote:
> That is what happens for "hand-rolled" `abs`, https://godbolt.org/g/6dbgXD
> I *think* this makes sense, since **IIRC** LLVM only supports
> twos-complement platforms.
> But all these attributes are curren
lebedev.ri added a comment.
That is what happens for "hand-rolled" `abs`, https://godbolt.org/g/6dbgXD
I *think* this makes sense, since **IIRC** LLVM only supports twos-complement
platforms.
But all these attributes are currently beyond me, so i won't click the accept
button :)
https://review
spatel created this revision.
spatel added reviewers: craig.topper, efriedma, lebedev.ri.
Herald added a subscriber: mcrosier.
The clang builtins have the same semantics as the stdlib functions.
The stdlib functions are defined in section 7.20.6.1 of the C standard with:
"If the result cannot be
