[Bug c++/85052] New: Implement support for clang's __builtin_convertvector

[kretz at kde dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85052

            Bug ID: 85052
           Summary: Implement support for clang's __builtin_convertvector
           Product: gcc
           Version: 8.0.1
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: kretz at kde dot org
  Target Milestone: ---

clang implements __builtin_convertvector to simplify conversions between
different vector builtins. In contrast to bitcasts, supported through C casts,
this builtin converts element-wise according to the standard type conversion
rules.

Documentation for the builtin:
https://clang.llvm.org/docs/LanguageExtensions.html#langext-builtin-convertvector

Related to PR85048.