[PATCH] D50616: [Fixed Point Arithmetic] FixedPointCast

[Roman Lebedev via Phabricator via cfe-commits]

lebedev.ri added a comment.

In https://reviews.llvm.org/D50616#1203751, @rjmccall wrote:

> In https://reviews.llvm.org/D50616#1203692, @ebevhan wrote:
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> Has anyone actually asked LLVM whether they would accept fixed-point types into IR?  I'm just a frontend guy, but it seems to me that there are advantages to directly representing these operations in a portable way even if there are no in-tree targets providing special support for them.  And there are certainly in-tree targets that could provide such support if someone was motivated to do it.


Even just adding one new LLVM IR instruction (well, intrinsic too, ideally) already 'requires' you to to
then go around and make sure it is properly handled wrt all the other instructions, optimizations, codegen.

Adding a whole new type, i suspect, would be *much* more impactful.
And since it can already be represented via existing operations on existing integer type,
it isn't obvious why that would be the right way forward.


Repository:
  rC Clang

https://reviews.llvm.org/D50616