Code motion with the same side effects in branches does not always work

It seems CodeFolding can't handle such case with side effects (division):

export function not_branchless_ceil_div(x: i32, y: i32): i32 {
  return x >= 0 ? x / y : (x + y - 1) / y;
}

export function branchless_ceil_div(x: i32, y: i32): i32 {
  return (x >= 0 ? x : x + y - 1) / y;
}

Which output:

(module
 (func (export "not_branchless_ceil_div") $a (param $0 i32) (param $1 i32) (result i32)
  local.get $0
  i32.const 0
  i32.ge_s
  if (result i32)
   local.get $0
   local.get $1
   i32.div_s
  else
   local.get $0
   local.get $1
   i32.add
   i32.const 1
   i32.sub
   local.get $1
   i32.div_s
  end
 )
 (func (export "branchless_ceil_div") $b (param $0 i32) (param $1 i32) (result i32)
  local.get $0
  local.get $0
  local.get $1
  i32.add
  i32.const 1
  i32.sub
  local.get $0
  i32.const 0
  i32.ge_s
  select
  local.get $1
  i32.div_s
 )
)

But with CodeFolding both code should be identically branchless.
Thought?

Start with the CodeFolding optimization and reproduce the issue using the two TypeScript functions and generated WAT shown here. Compare the folding behavior when division is inside each branch versus after the select, and determine whether the transformation can preserve the division side effects. Done means both functions produce equivalent branchless output without changing semantics.