tree 9ac561f1bf4d32b24cc710d5321bb31715ee981c
parent 2801c2a2b5db82d5dd1833bb3344f8411b42f5d2
author Vedant Kumar <vsk@apple.com> 1545167103 +0000
committer Vedant Kumar <vsk@apple.com> 1545167103 +0000

[CodeGen] Handle mixed-width ops in mixed-sign mul-with-overflow lowering

The special lowering for __builtin_mul_overflow introduced in r320902
fixed an ICE seen when passing mixed-sign operands to the builtin.

This patch extends the special lowering to cover mixed-width, mixed-sign
operands. In a few common scenarios, calls to muloti4 will no longer be
emitted.

This should address the latest comments in PR34920 and work around the
link failure seen in:

  https://bugzilla.redhat.com/show_bug.cgi?id=1657544

Testing:
- check-clang
- A/B output comparison with: https://gist.github.com/vedantk/3eb9c88f82e5c32f2e590555b4af5081

Differential Revision: https://reviews.llvm.org/D55843

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@349542 91177308-0d34-0410-b5e6-96231b3b80d8