[release-branch.go1.20] Revert "cmd/compile: teach prove about bitwis…

…e OR operation"

This reverts commit 3680b5e.

Reason for revert: causes long compile times on certain functions. See issue #57959

Change-Id: Ie9e881ca8abbc79a46de2bfeaed0b9d6c416ed42
Reviewed-on: https://go-review.googlesource.com/c/go/+/463295
Run-TryBot: Keith Randall <khr@golang.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
(cherry picked from commit a6ddb15)
Reviewed-on: https://go-review.googlesource.com/c/go/+/463415
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Keith Randall <khr@google.com>

src/cmd/compile/internal/ssa/prove.go

@@ -856,9 +856,6 @@ func prove(f *Func) {
 			case OpAnd64, OpAnd32, OpAnd16, OpAnd8:
 				ft.update(b, v, v.Args[1], unsigned, lt|eq)
 				ft.update(b, v, v.Args[0], unsigned, lt|eq)
-			case OpOr64, OpOr32, OpOr16, OpOr8:
-				ft.update(b, v, v.Args[1], unsigned, gt|eq)
-				ft.update(b, v, v.Args[0], unsigned, gt|eq)
 			case OpPhi:
 				// Determine the min and max value of OpPhi composed entirely of integer constants.
 				//

test/prove.go

@@ -1053,11 +1053,6 @@ func issue51622(b []byte) int {
 	return 0
 }
 
-func issue45928(x int) {
-	combinedFrac := (x) / (x | (1 << 31)) // ERROR "Proved Neq64$"
-	useInt(combinedFrac)
-}
-
 //go:noinline
 func useInt(a int) {
 }