If the truncate is only accessing the first element of the vector,
we can use the original source value.
This helps with some combine ordering issues after operations are
lowered to integer operations between bitcasts of build_vector.
In particular it stops unnecessarily materializing the unused
top half of a vector in some cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331909 91177308-0d34-0410-b5e6-96231b3b80d8
GFX9 does not enable bounds checking for the resource descriptors
used for private access, so it should be OK to use vaddr with
a potentially negative value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@319393 91177308-0d34-0410-b5e6-96231b3b80d8
Partially implement callee-side for arguments and return values.
byval doesn't work properly, and most likely sret or other on-stack
return values most as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@303308 91177308-0d34-0410-b5e6-96231b3b80d8
