This patch "modernizes" the LLVM `insertvalue` and `extractvalue`
operations to use DenseI64ArrayAttr, since they only require an array of
indices and previously there was confusion about whether to use i32 or
i64 arrays, and to use assembly format.
Reviewed By: ftynse
Differential Revision: https://reviews.llvm.org/D131537
And move importer test files from `test/Target/LLVMIR` into
`test/Target/LLVMIR/Import`.
We simply translate struct-type ConstantAggregate(Zero) into a
serious of `llvm.insertvalue` operations against a `llvm.undef` root.
Note that this doesn't affect the original logics on translating
vector/array-type ConstantAggregate values.
Differential Revision: https://reviews.llvm.org/D124399