go/test/shift3.go
Robert Griesemer c0bbeb0982 cmd/compile: adjust types2 shift check to match go/types (cleanup)
With this change, the shift checking code matches the corresponding
go/types code, but for the differences in the internal error reporting,
and call of check.overflow.

The change leads to the recording of an untyped int value if the RHS
of a non-constant shift is an untyped integer value. Adjust the type
in the compiler's irgen accordingly. Add test/shift3.go to verify
behavior.

Change-Id: I20386fcb1d5c48becffdc2203081fb70c08b282d
Reviewed-on: https://go-review.googlesource.com/c/go/+/398236
Trust: Robert Griesemer <gri@golang.org>
Run-TryBot: Robert Griesemer <gri@golang.org>
Trust: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>
2022-04-07 17:19:55 +00:00

41 lines
834 B
Go

// run
// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Test that the compiler's noder uses the correct type
// for RHS shift operands that are untyped. Must compile;
// run for good measure.
package main
import (
"fmt"
"math"
)
func f(x, y int) {
if x != y {
panic(fmt.Sprintf("%d != %d", x, y))
}
}
func main() {
var x int = 1
f(x<<1, 2)
f(x<<1., 2)
f(x<<(1+0i), 2)
f(x<<0i, 1)
f(x<<(1<<x), 4)
f(x<<(1.<<x), 4)
f(x<<((1+0i)<<x), 4)
f(x<<(0i<<x), 1)
// corner cases
const M = math.MaxUint
f(x<<(M+0), 0) // shift by untyped int representable as uint
f(x<<(M+0.), 0) // shift by untyped float representable as uint
f(x<<(M+0.+0i), 0) // shift by untyped complex representable as uint
}