From: Wayne Zuo <wdvxdr@golangcn.org>
Date: Sun, 5 Jun 2022 05:22:29 +0000 (+0800)
Subject: cmd/compile: teach prove about bitwise OR operation
X-Git-Tag: go1.20rc1~1334
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=3680b5e9c4f42fcf9155aa42b3b344d1fbe19571;p=gostls13.git

cmd/compile: teach prove about bitwise OR operation

Fixes #45928.

Change-Id: Ifbb0effbca4ab7c0eb56069fee40edb564553c35
Reviewed-on: https://go-review.googlesource.com/c/go/+/410336
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Run-TryBot: Wayne Zuo <wdvxdr@golangcn.org>
Reviewed-by: David Chase <drchase@google.com>
Reviewed-by: Than McIntosh <thanm@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
---

diff --git a/src/cmd/compile/internal/ssa/prove.go b/src/cmd/compile/internal/ssa/prove.go
index cebadcb42c..20c967d098 100644
--- a/src/cmd/compile/internal/ssa/prove.go
+++ b/src/cmd/compile/internal/ssa/prove.go
@@ -842,6 +842,9 @@ 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)
 			}
 		}
 	}
diff --git a/test/prove.go b/test/prove.go
index 5ccaff54ce..1be257f206 100644
--- a/test/prove.go
+++ b/test/prove.go
@@ -1053,6 +1053,11 @@ 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) {
 }