Summary:
Wasm does not currently support `llvm.clear_cache` intrinsic, and this
prints a proper error message instead of segfault.
Reviewers: dschuff, sbc100, sunfish
Subscribers: jgravelle-google, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64322
llvm-svn: 365731