[llvm] [InstSimplify] Simplify select if it combinated `and/or/xor` (PR #73362)

[via llvm-commits]

ParkHanbum wrote:

@dtcxzyw I commented on the comment above, can you see it? It says (pending) on my screen, but I don't know why, but it may mean that it hasn't been uploaded. So I'll reply here again.



I think it is necessary. because Select ICmp is must be "X (comp) Y". here is example:
```
define i32 @src_select_xor_max_positive_int(i32 %x, i32 %y) {
; CHECK-LABEL: @src_select_xor_max_positive_int(
; CHECK-NEXT:    [[XOR:%.*]] = xor i32 [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT:    [[XOR0:%.*]] = icmp eq i32 [[XOR]], 2147483647
; CHECK-NEXT:    [[AND:%.*]] = and i32 [[X]], [[Y]]
; CHECK-NEXT:    [[OR:%.*]] = or i32 [[X]], [[Y]]
; CHECK-NEXT:    [[COND:%.*]] = select i1 [[XOR0]], i32 [[AND]], i32 [[OR]]
; CHECK-NEXT:    ret i32 [[COND]]
;
  %xor = xor i32 %x, %y
  %xor0 = icmp eq i32 %xor, 2147483647
  %and = and i32 %x, %y
  %or = or i32 %x, %y
  %cond = select i1 %xor0, i32 %and, i32 %or
  ret i32 %cond
}
```
without `if (match(CmpLHS, m_Value(X)) && match(CmpRHS, m_Value(Y))) {` condition then
  `%and = and i32 %x, %y %or = or i32 %x, %y`
will match case.

am I right?




https://github.com/llvm/llvm-project/pull/73362