tree 508f9083a871e2cb37fd001d4df0e5ced4e4b5ff
parent 60288600131c3f91bfc8ba512df9f2dd588e3308
author Hal Finkel <hfinkel@anl.gov> 1379474985 +0000
committer Hal Finkel <hfinkel@anl.gov> 1379474985 +0000

Add the intrinsic __builtin_convertvector

LLVM supports applying conversion instructions to vectors of the same number of
elements (fptrunc, fptosi, etc.) but there had been no way for a Clang user to
cause such instructions to be generated when using builtin vector types.

C-style casting on vectors is already defined in terms of bitcasts, and so
cannot be used for these conversions as well (without leading to a very
confusing set of semantics). As a result, this adds a __builtin_convertvector
intrinsic (patterned after the OpenCL __builtin_astype intrinsic). This is
intended to aid the creation of vector intrinsic headers that create generic IR
instead of target-dependent intrinsics (in other words, this is a generic
_mm_cvtepi32_ps). As noted in the documentation, the action of
__builtin_convertvector is defined in terms of the action of a C-style cast on
each vector element.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@190915 91177308-0d34-0410-b5e6-96231b3b80d8