[dev.cmdgo] all: merge master (5e6a7e9) into dev.cmdgo

Merge List:

+ 2021-08-26 5e6a7e9b86 embed: remove reference to global variables in docs
+ 2021-08-26 166b691b65 cmd/compile/internal/types2: remove need for instance (struct)
+ 2021-08-26 d6bdae33e9 cmd/compile/internal/types2: address some TODOs (cleanup)
+ 2021-08-26 770df2e18d crypto/tls: fix typo in PreferServerCipherSuites comment
+ 2021-08-26 a6ff433d6a cmd/go: pass -gcflags after other flags generated by the go command
+ 2021-08-25 4f2620285d cmd/compile/internal/types2: fix type set printing and add test
+ 2021-08-25 0ac64f6d70 cmd/compile/internal/types2: rename IsMethodSet to IsConstraint (cleanup)
+ 2021-08-25 4068fb6c21 cmd/compile: always accept 1.18 syntax but complain if not 1.18
+ 2021-08-25 bf0bc4122f go/types, types2: don't re-evaluate context string for each function argument (optimization)
+ 2021-08-25 4158e88f64 cmd/compile/internal/syntax: fix position of type parameter field
+ 2021-08-25 647bef6c59 go/types: implement NewTypeList and use it instead of composite literals
+ 2021-08-25 6cf1d5d0fa cmd/compile: generic SSA rules for simplifying 2 and 3 operand integer arithmetic expressions
+ 2021-08-25 5baf60d472 bytes, strings: optimize Trim for single byte cutsets
+ 2021-08-25 3d667671ad cmd/compile: fix function contains no TParam in generic function
+ 2021-08-25 4f2ebfe34b cmd/compile: allow embed into any byte slice type
+ 2021-08-25 d2f002cb39 time/format: avoid growslice in time.String()/time.GoString()
+ 2021-08-25 08d4cc20ca cmd/compile: fix stencil call expression.
+ 2021-08-25 099b819085 cmd/compile: fix CheckSize() calculation for -G=3 and stencils
+ 2021-08-25 e1fcf8857e test: add test that caused gofrontend compiler crash
+ 2021-08-25 d37b8dedf7 test: add test case that gofrontend miscompiled
+ 2021-08-25 41b99dab0f os/user: don't skip TestLookupGroup if supported
+ 2021-08-25 de1c934b97 cmd/compile: fix checkptr false positive for (*[Big]T)(ptr)[:n:n] pattern
+ 2021-08-24 54cdef1f10 reflect: add MapIter.SetKey and MapIter.SetValue
+ 2021-08-24 5d863f89fe cmd/compile: simplify bad conversion check

Change-Id: I29ab927f0e47f44d82f9307c642900f75f4f678f

9 files changed, 203 insertions, 1 deletions

diff --git a/test/codegen/arithmetic.go b/test/codegen/arithmetic.go
index eb0f338036..eb95416b6a 100644
--- a/test/codegen/arithmetic.go
+++ b/test/codegen/arithmetic.go
@@ -84,6 +84,30 @@ func NegAddFromConstNeg(a int) int {
 	return c
 }
 
+func SubSubNegSimplify(a, b int) int {
+	// amd64:"NEGQ"
+	r := (a - b) - a
+	return r
+}
+
+func SubAddSimplify(a, b int) int {
+	// amd64:-"SUBQ",-"ADDQ"
+	r := a + (b - a)
+	return r
+}
+
+func SubAddNegSimplify(a, b int) int {
+	// amd64:"NEGQ",-"ADDQ",-"SUBQ"
+	r := a - (b + a)
+	return r
+}
+
+func AddAddSubSimplify(a, b, c int) int {
+	// amd64:-"SUBQ"
+	r := a + (b + (c - a))
+	return r
+}
+
 // -------------------- //
 //    Multiplication    //
 // -------------------- //
diff --git a/test/fixedbugs/gcc101994.go b/test/fixedbugs/gcc101994.go
new file mode 100644
index 0000000000..6e1e2b8075
--- /dev/null
+++ b/test/fixedbugs/gcc101994.go
@@ -0,0 +1,16 @@
+// compile
+
+// Copyright 2021 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.
+
+// https://gcc.gnu.org/PR101994
+// gccgo compiler crash with zero-sized result.
+
+package p
+
+type Empty struct{}
+
+func F() (int, Empty) {
+	return 0, Empty{}
+}
diff --git a/test/fixedbugs/issue10975.go b/test/fixedbugs/issue10975.go
index 876ea58ef9..a58ccce2db 100644
--- a/test/fixedbugs/issue10975.go
+++ b/test/fixedbugs/issue10975.go
@@ -10,7 +10,7 @@
 package main
 
 type I interface {
-	int // ERROR "interface contains embedded non-interface|not an interface"
+	int // ERROR "interface contains embedded non-interface|embedding non-interface type"
 }
 
 func New() I {
diff --git a/test/fixedbugs/issue46938.go b/test/fixedbugs/issue46938.go
new file mode 100644
index 0000000000..87532d4769
--- /dev/null
+++ b/test/fixedbugs/issue46938.go
@@ -0,0 +1,29 @@
+// run -gcflags="-d=checkptr"
+
+// Copyright 2021 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.
+
+package main
+
+import (
+	"strings"
+	"unsafe"
+)
+
+func main() {
+	defer func() {
+		err := recover()
+		if err == nil {
+			panic("expected panic")
+		}
+		if got := err.(error).Error(); !strings.Contains(got, "slice bounds out of range") {
+			panic("expected panic slice out of bound, got " + got)
+		}
+	}()
+	s := make([]int64, 100)
+	p := unsafe.Pointer(&s[0])
+	n := 1000
+
+	_ = (*[10]int64)(p)[:n:n]
+}
diff --git a/test/fixedbugs/issue47771.go b/test/fixedbugs/issue47771.go
new file mode 100644
index 0000000000..a434bffe4b
--- /dev/null
+++ b/test/fixedbugs/issue47771.go
@@ -0,0 +1,19 @@
+// run
+
+// Copyright 2021 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.
+
+// gofrontend miscompiled some cases of append(s, make(typ, ln)...).
+
+package main
+
+var g int
+
+func main() {
+	a := []*int{&g, &g, &g, &g}
+	a = append(a[:0], make([]*int, len(a) - 1)...)
+	if len(a) != 3 || a[0] != nil || a[1] != nil || a[2] != nil {
+		panic(a)
+	}
+}
diff --git a/test/typeparam/issue47878.go b/test/typeparam/issue47878.go
new file mode 100644
index 0000000000..cb1043a440
--- /dev/null
+++ b/test/typeparam/issue47878.go
@@ -0,0 +1,46 @@
+// compile -G=3
+
+// Copyright 2021 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.
+
+package main
+
+type Src1[T any] func() Src1[T]
+
+func (s *Src1[T]) Next() {
+	*s = (*s)()
+}
+
+type Src2[T any] []func() Src2[T]
+
+func (s Src2[T]) Next() {
+	_ = s[0]()
+}
+
+type Src3[T comparable] map[T]func() Src3[T]
+
+func (s Src3[T]) Next() {
+	var a T
+	_ = s[a]()
+}
+
+type Src4[T any] chan func() T
+
+func (s Src4[T]) Next() {
+	_ = (<-s)()
+}
+
+func main() {
+	var src1 Src1[int]
+	src1.Next()
+
+	var src2 Src2[int]
+	src2.Next()
+
+	var src3 Src3[string]
+	src3.Next()
+
+	var src4 Src4[int]
+	src4.Next()
+}
diff --git a/test/typeparam/issue47901.go b/test/typeparam/issue47901.go
new file mode 100644
index 0000000000..cd07973011
--- /dev/null
+++ b/test/typeparam/issue47901.go
@@ -0,0 +1,21 @@
+// run -gcflags=-G=3
+
+// Copyright 2021 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.
+
+package main
+
+type Chan[T any] chan Chan[T]
+
+func (ch Chan[T]) recv() Chan[T] {
+	return <-ch
+}
+
+func main() {
+	ch := Chan[int](make(chan Chan[int]))
+	go func() {
+		ch <- make(Chan[int])
+	}()
+	ch.recv()
+}
diff --git a/test/typeparam/issue47929.go b/test/typeparam/issue47929.go
new file mode 100644
index 0000000000..a5636f2c7b
--- /dev/null
+++ b/test/typeparam/issue47929.go
@@ -0,0 +1,29 @@
+// compile -G=3 -p=p
+
+// Copyright 2021 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.
+
+package v4
+
+var sink interface{}
+
+//go:noinline
+func Do(result, body interface{}) {
+	sink = &result
+}
+
+func DataAction(result DataActionResponse, body DataActionRequest) {
+	Do(&result, body)
+}
+
+type DataActionRequest struct {
+	Action *interface{}
+}
+
+type DataActionResponse struct {
+	ValidationErrors *ValidationError
+}
+
+type ValidationError struct {
+}
diff --git a/test/typeparam/issue47948.go b/test/typeparam/issue47948.go
new file mode 100644
index 0000000000..8e5df81f6d
--- /dev/null
+++ b/test/typeparam/issue47948.go
@@ -0,0 +1,18 @@
+// compile -G=3
+
+// Copyright 2021 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.
+
+package main
+
+type fun func()
+
+func F[T any]() {
+	_ = fun(func() {
+
+	})
+}
+func main() {
+	F[int]()
+}