test dce

function %simple() -> i32 {
ebb0:
    v2 = iconst.i32 2
    v3 = iconst.i32 3
    return v3
}
; sameln: function %simple
; nextln: ebb0:
; nextln:     v3 = iconst.i32 3
; nextln:     return v3
; nextln: }

function %some_branching(i32, i32) -> i32 {
ebb0(v0: i32, v1: i32):
    v3 = iconst.i32 70
    v4 = iconst.i32 71
    v5 = iconst.i32 72
    v8 = iconst.i32 73
    brz v0, ebb1
    jump ebb2(v8)

ebb1:
    v2 = iadd v0, v3
    return v0

ebb2(v9: i32):
    v6 = iadd v1, v4
    v7 = iadd v6, v9
    return v7
}
; sameln: function %some_branching
; nextln: ebb0(v0: i32, v1: i32):
; nextln:     v4 = iconst.i32 71
; nextln:     v8 = iconst.i32 73
; nextln:     brz v0, ebb1
; nextln:     jump ebb2(v8)
; nextln: 
; nextln: ebb1:
; nextln:     return v0
; nextln: 
; nextln: ebb2(v9: i32):
; nextln:     v6 = iadd.i32 v1, v4
; nextln:     v7 = iadd v6, v9
; nextln:     return v7