mirror of
https://github.com/golang/go
synced 2024-11-24 09:20:02 -07:00
e99e9a6e01
The compiler renames anonymous and blank result parameters to ~rN or ~bN, but the current semantics for computing N are rather annoying and difficult to reproduce cleanly. They also lead to difficult to read escape analysis results in tests. This CL changes N to always be calculated as the parameter's index within the function's result parameter tuple. E.g., if a function has a single result, it will now always be named "~r0". The normative change to this CL is fairly simple, but it requires updating a lot of test expectations. Change-Id: I58a3c94de00cb822cb94efe52d115531193c993c Reviewed-on: https://go-review.googlesource.com/c/go/+/323010 Trust: Matthew Dempsky <mdempsky@google.com> Trust: Dan Scales <danscales@google.com> Run-TryBot: Matthew Dempsky <mdempsky@google.com> TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Dan Scales <danscales@google.com>
70 lines
2.2 KiB
Go
70 lines
2.2 KiB
Go
// errorcheck -0 -m -l
|
|
|
|
// Copyright 2019 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 escape analysis for unsafe.Pointer rules.
|
|
|
|
package escape
|
|
|
|
import (
|
|
"reflect"
|
|
"unsafe"
|
|
)
|
|
|
|
// (1) Conversion of a *T1 to Pointer to *T2.
|
|
|
|
func convert(p *float64) *uint64 { // ERROR "leaking param: p to result ~r0 level=0$"
|
|
return (*uint64)(unsafe.Pointer(p))
|
|
}
|
|
|
|
// (3) Conversion of a Pointer to a uintptr and back, with arithmetic.
|
|
|
|
func arithAdd() unsafe.Pointer {
|
|
var x [2]byte // ERROR "moved to heap: x"
|
|
return unsafe.Pointer(uintptr(unsafe.Pointer(&x[0])) + 1)
|
|
}
|
|
|
|
func arithSub() unsafe.Pointer {
|
|
var x [2]byte // ERROR "moved to heap: x"
|
|
return unsafe.Pointer(uintptr(unsafe.Pointer(&x[1])) - 1)
|
|
}
|
|
|
|
func arithMask() unsafe.Pointer {
|
|
var x [2]byte // ERROR "moved to heap: x"
|
|
return unsafe.Pointer(uintptr(unsafe.Pointer(&x[1])) &^ 1)
|
|
}
|
|
|
|
// (5) Conversion of the result of reflect.Value.Pointer or
|
|
// reflect.Value.UnsafeAddr from uintptr to Pointer.
|
|
|
|
// BAD: should be "leaking param: p to result ~r0 level=0$"
|
|
func valuePointer(p *int) unsafe.Pointer { // ERROR "leaking param: p$"
|
|
return unsafe.Pointer(reflect.ValueOf(p).Pointer())
|
|
}
|
|
|
|
// BAD: should be "leaking param: p to result ~r0 level=0$"
|
|
func valueUnsafeAddr(p *int) unsafe.Pointer { // ERROR "leaking param: p$"
|
|
return unsafe.Pointer(reflect.ValueOf(p).Elem().UnsafeAddr())
|
|
}
|
|
|
|
// (6) Conversion of a reflect.SliceHeader or reflect.StringHeader
|
|
// Data field to or from Pointer.
|
|
|
|
func fromSliceData(s []int) unsafe.Pointer { // ERROR "leaking param: s to result ~r0 level=0$"
|
|
return unsafe.Pointer((*reflect.SliceHeader)(unsafe.Pointer(&s)).Data)
|
|
}
|
|
|
|
func fromStringData(s string) unsafe.Pointer { // ERROR "leaking param: s to result ~r0 level=0$"
|
|
return unsafe.Pointer((*reflect.StringHeader)(unsafe.Pointer(&s)).Data)
|
|
}
|
|
|
|
func toSliceData(s *[]int, p unsafe.Pointer) { // ERROR "s does not escape" "leaking param: p$"
|
|
(*reflect.SliceHeader)(unsafe.Pointer(s)).Data = uintptr(p)
|
|
}
|
|
|
|
func toStringData(s *string, p unsafe.Pointer) { // ERROR "s does not escape" "leaking param: p$"
|
|
(*reflect.SliceHeader)(unsafe.Pointer(s)).Data = uintptr(p)
|
|
}
|