[llvm] [LVI][SCCP][CVP] Add basic ConstantFPRange support (PR #111544)

[Yingwei Zheng via llvm-commits]

================
@@ -233,21 +233,22 @@ static Value *getValueOnEdge(LazyValueInfo *LVI, Value *Incoming,
   // value can never be that constant. In that case replace the incoming
   // value with the other value of the select. This often allows us to
   // remove the select later.
+  if (!SI->getType()->isFPOrFPVectorTy()) {
----------------
dtcxzyw wrote:

It also handles the pointer case. See also Transforms/CorrelatedValuePropagation/basic.ll:
```

; "true" case for CorrelatedValuePropagation
define void @loop2(ptr %x, ptr %y) {
; CHECK-LABEL: define void @loop2
; CHECK-SAME: (ptr [[X:%.*]], ptr [[Y:%.*]]) {
; CHECK-NEXT:  entry:
; CHECK-NEXT:    br label [[LOOP:%.*]]
; CHECK:       loop:
; CHECK-NEXT:    [[PHI:%.*]] = phi ptr [ [[F:%.*]], [[LOOP]] ], [ [[X]], [[ENTRY:%.*]] ]
; CHECK-NEXT:    [[F]] = tail call ptr @f(ptr [[PHI]])
; CHECK-NEXT:    [[CMP1:%.*]] = icmp eq ptr [[F]], [[Y]]
; CHECK-NEXT:    [[SEL:%.*]] = select i1 [[CMP1]], ptr null, ptr [[F]]
; CHECK-NEXT:    [[CMP2:%.*]] = icmp eq ptr [[SEL]], null
; CHECK-NEXT:    br i1 [[CMP2]], label [[RETURN:%.*]], label [[LOOP]]
; CHECK:       return:
; CHECK-NEXT:    ret void
;
entry:
  br label %loop

loop:
  %phi = phi ptr [ %sel, %loop ], [ %x, %entry ]
  %f = tail call ptr @f(ptr %phi)
  %cmp1 = icmp eq ptr %f, %y
  %sel = select i1 %cmp1, ptr null, ptr %f
  %cmp2 = icmp eq ptr %sel, null
  br i1 %cmp2, label %return, label %loop

return:
  ret void
}
```

https://github.com/llvm/llvm-project/pull/111544