Failure with `lshr_int` (intrinsic for >>) on UInt256 type

General Usage
4

It looks like it’s an LLVM bug:

julia> primitive type UInt256 256 end

julia> x = reinterpret(UInt256, rand(UInt128, 2))[]
UInt256(0x48805fdfb72d71fadaf8daa563cf816383f755d9d9e70d703fa348f556c717ad)

julia> f(x) = Base.lshr_int(x, 0x8)
f (generic function with 1 method)

julia> @code_llvm optimize=false f(x)
;  @ REPL[22]:1 within `f'
define void @julia_f_392(i256* noalias nocapture sret %0, i256 %1) {
top:
  %2 = call {}*** @julia.ptls_states()
  %3 = bitcast {}*** %2 to {}**
  %4 = getelementptr inbounds {}*, {}** %3, i64 4
  %5 = bitcast {}** %4 to i64**
  %6 = load i64*, i64** %5
  %7 = lshr i256 %1, 8
  %8 = select i1 true, i256 0, i256 %7
  store i256 %8, i256* %0, align 8
  ret void
}

julia> @code_llvm optimize=true f(x)
;  @ REPL[22]:1 within `f'
define void @julia_f_394(i256* noalias nocapture sret %0, i256 %1) {
top:
  store i256 0, i256* %0, align 8
  ret void
}

Would you mind opening an issue on GitHub?

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