This reverts commit 2ba016cd5ce50a3683d3e6c2c62f00e1cccfd8b5.
This is causing a failure on the clang-cmake-armv7-full bot, and there
are outstanding review comments.
Similar to ceb801612a678bdffe7e7bf163bd0eed9c9b73a2.
Darwin doesn't always use compiler-rt, and so we can't assume that these
functions are available on arm.
And instead just generate a libcall. My motivating example on ARM was a simple:
shl i64 %A, %B
for which the code bloat is quite significant. For other targets that also
accept __int128/i128 such as AArch64 and X86, it is also beneficial for these
cases to generate a libcall when optimising for minsize. On these 64-bit targets,
the 64-bits shifts are of course unaffected because the SHIFT/SHIFT_PARTS
lowering operation action is not set to custom/expand.
Differential Revision: https://reviews.llvm.org/D57386
llvm-svn: 352736
