[gopls-release-branch.0.5] all: merge master into gopls-release-branch.0.5

3db8fd2 internal/lsp: use a structured format for the server's version
8694a4a internal/lsp/source: don't find possible interface references to types
78b1585 internal/lsp/fake: reflect on-disk changes in clean buffers
bc9fc8d internal/lsp: fix flickering analysis diagnostics
bc3cf28 go/loader: loosen a test assertion on go/types error messages
22bd852 internal/lsp: remove organize imports action for go.mod
aefe0b7 internal/lsp: set correct directness when adding new requires
330dc7d internal/lsp/cache: assign a static temp workspace dir to the first view
b653051 internal/lsp/cmd: delete TestDefinitionHelpExample test
ac612af internal/lsp: fix the logic to avoid duplicate file watching
6d1a7fa internal/imports: handle out of range panic in modInfo
7ad286a internal/lsp: check for nil snapshot in didModifyFiles
c64668f internal/lsp: do not rename in compiler directive comments
f46e424 internal/lsp/cache: handle nil pointer exception in missing module error
3f6de07 internal/lsp: make Diagnostics.CodeDescription a pointer
3288bc1 go/analysis: add frame pointer check for vet
b53d4cb internal/lsp/cache: check for symlinks when checking "isSubdirectory"
8860a70 internal/lsp/cache: set a 15 minute deadline on calls to packages.Load
51cde52 internal/lsp: move initialization entirely into the snapshot
1f28ee6 internal/lsp: change `go mod vendor` warning into a diagnostic
582c62e go/analysis/singlechecker: fix whitespace in package documentation
4fc0492 internal/lsp/cache: keep a cached workspace module dir
3734b81 internal/lsp: delay longer in TestDebouncer
d36b6f6 internal/memoize: add a final argument to Bind for cleaning up
f239dba internal/lsp/cache: consider gopls.mod when finding workspace root
d463eb0 internal/lsp/cache: introduce a workspace abstraction
443cd81 Revert "internal/lsp: move initialization entirely into the snapshot"
deb1282 internal/lsp: move initialization entirely into the snapshot
8da1a62 internal/lsp/source/completion: remove "completion_" prefix from files
589136c cmd/fiximports,cmd/present,cmd/stringer: update links to pkg.go.dev
cf7a54d internal/lsp/source: use bestMatch for fully qualified symbol style
63f8a17 internal/lsp: use the correct method name to register semantic tokens
2feb2bb internal/lsp: elide details for non-package files
186a743 internal/lsp/source: respect user's hover kind in signature help
061905c internal/lsp/cache: stop unnecessarily waiting for IWL
c86e623 internal/lsp/source: add missing vet analyzers
e7a17c4 internal/lsp/cache: preserve OS environment
690a3c2 go/analysis/passes/asmdecl: permit return jump without writing to results
2c11599 internal/lsp: use the go command to fix go.mod files
4972913 internal/lsp: unify go command invocation logic
832c4b4 internal/lsp/source: tweak the WorkspaceSymbols docstring
2b84a06 internal/lsp: use gocommand.Invocation more
5bbba66 internal/lsp/source: synchronous commands the default
dc70f74 internal/lsp: correct typo
0dcbe36 gopls/doc: update links from godoc.org to pkg.go.dev
eafbe7b internal/lsp/protocol/typescript: code for latest 3.16 LSP
8cd080b internal/lsp: handle nil pointer exceptions in check for Go files
0b86805 internal/lsp: finish work when synchronous commands complete
6312208 go/internal/gccgoimporter: support notinheap annotation
8dabb74 internal/lsp: update lsp protocol stubs to match LSP 3.16 revisions
e84cfc6 all: clear GOMODCACHE in tests
c8cfbd0 internal/lsp/source: handle nil pointer in rename_check.go
2f4fa18 go/packages: use native overlay support for 1.16
ffe8bce cmd/stress: print elapsed time, percentage failure
13b3b30 internal/lsp/semantic.go: remove global variable
9cf592e all: update all dependencies to latest pseudoversions

Change-Id: I1e690a9cb361ed05cc1d184951e06b3e2099dc08

Author: stamblerre

cmd/fiximports/main.go

@@ -114,7 +114,7 @@ The package... arguments specify a list of packages
 in the style of the go tool; see "go help packages".
 Hint: use "all" or "..." to match the entire workspace.
 
-For details, see http://godoc.org/golang.org/x/tools/cmd/fiximports.
+For details, see https://pkg.go.dev/golang.org/x/tools/cmd/fiximports
 
 Flags:
   -n:	       dry run: show changes, but don't apply them

cmd/present/doc.go

@@ -47,6 +47,6 @@ the generated output. The supported formats are:
 	.article      // article format, such as a blog post
 
 The present file format is documented by the present package:
-http://godoc.org/golang.org/x/tools/present
+https://pkg.go.dev/golang.org/x/tools/present
 */
 package main

cmd/stress/stress.go

@@ -113,6 +113,7 @@ func main() {
 		}()
 	}
 	runs, fails := 0, 0
+	start := time.Now()
 	ticker := time.NewTicker(5 * time.Second).C
 	for {
 		select {
@@ -137,7 +138,12 @@ func main() {
 				fmt.Printf("\n%s\n%s\n", f.Name(), out)
 			}
 		case <-ticker:
-			fmt.Printf("%v runs so far, %v failures\n", runs, fails)
+			elapsed := time.Since(start).Truncate(time.Second)
+			var pct string
+			if fails > 0 {
+				pct = fmt.Sprintf(" (%0.2f%%)", 100.0*float64(fails)/float64(runs))
+			}
+			fmt.Printf("%v: %v runs so far, %v failures%s\n", elapsed, runs, fails, pct)
 		}
 	}
 }

cmd/stringer/stringer.go

@@ -98,7 +98,7 @@ func Usage() {
 	fmt.Fprintf(os.Stderr, "\tstringer [flags] -type T [directory]\n")
 	fmt.Fprintf(os.Stderr, "\tstringer [flags] -type T files... # Must be a single package\n")
 	fmt.Fprintf(os.Stderr, "For more information, see:\n")
-	fmt.Fprintf(os.Stderr, "\thttp://godoc.org/golang.org/x/tools/cmd/stringer\n")
+	fmt.Fprintf(os.Stderr, "\thttps://pkg.go.dev/golang.org/x/tools/cmd/stringer\n")
 	fmt.Fprintf(os.Stderr, "Flags:\n")
 	flag.PrintDefaults()
 }

go.mod

@@ -5,7 +5,7 @@ go 1.12
 require (
 	github.com/yuin/goldmark v1.2.1
 	golang.org/x/mod v0.3.0
-	golang.org/x/net v0.0.0-20200822124328-c89045814202
-	golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208
+	golang.org/x/net v0.0.0-20201021035429-f5854403a974
+	golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
 )

go.sum

@@ -6,22 +6,20 @@ golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/mod v0.3.0 h1:RM4zey1++hCTbCVQfnWeKs9/IEsaBLA8vTkd0WVtmH4=
 golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859 h1:R/3boaszxrf1GEUWTVDzSKVwLmSJpwZ1yqXm8j0v2QI=
 golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20200822124328-c89045814202 h1:VvcQYSHwXgi7W+TpUR6A9g6Up98WAHf3f/ulnJ62IyA=
-golang.org/x/net v0.0.0-20200822124328-c89045814202/go.mod h1:/O7V0waA8r7cgGh81Ro3o1hOxt32SMVPicZroKQ2sZA=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58 h1:8gQV6CLnAEikrhgkHFbMAEhagSSnXWGV915qUMm9mrU=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974 h1:IX6qOQeG5uLjB/hjjwjedwfjND0hgjPMMyO1RoIXQNI=
+golang.org/x/net v0.0.0-20201021035429-f5854403a974/go.mod h1:sp8m0HH+o8qH0wwXwYZr8TS3Oi6o0r6Gce1SSxlDquU=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208 h1:qwRHBd0NqMbJxfbotnDhm2ByMI1Shq4Y6oRJo21SGJA=
-golang.org/x/sync v0.0.0-20200625203802-6e8e738ad208/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a h1:1BGLXjeY4akVXGgbC9HugT3Jv3hCI0z56oJR5vAMgBU=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9 h1:SQFwaSi55rU7vdNs9Yr0Z324VNlrF+0wMqRXT4St8ck=
+golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
+golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
 golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
 golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898 h1:/atklqdjdhuosWIl6AIbOeHJjicWYPqR9bpxqxYG2pA=
 golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=

go/analysis/passes/asmdecl/asmdecl.go

@@ -308,7 +308,8 @@ Files:
 				continue
 			}
 
-			if strings.Contains(line, "RET") {
+			if strings.Contains(line, "RET") && !strings.Contains(line, "(SB)") {
+				// RET f(SB) is a tail call. It is okay to not write the results.
 				retLine = append(retLine, lineno)
 			}
 

go/analysis/passes/asmdecl/testdata/src/a/asm.go

@@ -51,3 +51,5 @@ func fvariadic(int, ...int)
 func pickStableABI(x int)
 func pickInternalABI(x int)
 func pickFutureABI(x int)
+
+func retjmp() int

go/analysis/passes/asmdecl/testdata/src/a/asm1.s

@@ -345,3 +345,7 @@ TEXT ·pickInternalABI<ABIInternal>(SB), NOSPLIT, $32
 TEXT ·pickFutureABI<ABISomethingNotyetInvented>(SB), NOSPLIT, $32
 	MOVQ	x+0(FP), AX
 	RET
+
+// return jump
+TEXT ·retjmp(SB), NOSPLIT, $0-8
+	RET	retjmp1(SB) // It's okay to not write results if there's a tail call.

go/analysis/passes/framepointer/framepointer.go

@@ -0,0 +1,91 @@
+// Copyright 2020 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 framepointer defines an Analyzer that reports assembly code
+// that clobbers the frame pointer before saving it.
+package framepointer
+
+import (
+	"go/build"
+	"regexp"
+	"strings"
+
+	"golang.org/x/tools/go/analysis"
+	"golang.org/x/tools/go/analysis/passes/internal/analysisutil"
+)
+
+const Doc = "report assembly that clobbers the frame pointer before saving it"
+
+var Analyzer = &analysis.Analyzer{
+	Name: "framepointer",
+	Doc:  Doc,
+	Run:  run,
+}
+
+var (
+	re             = regexp.MustCompile
+	asmWriteBP     = re(`,\s*BP$`) // TODO: can have false positive, e.g. for TESTQ BP,BP. Seems unlikely.
+	asmMentionBP   = re(`\bBP\b`)
+	asmControlFlow = re(`^(J|RET)`)
+)
+
+func run(pass *analysis.Pass) (interface{}, error) {
+	if build.Default.GOARCH != "amd64" { // TODO: arm64 also?
+		return nil, nil
+	}
+	if build.Default.GOOS != "linux" && build.Default.GOOS != "darwin" {
+		return nil, nil
+	}
+
+	// Find assembly files to work on.
+	var sfiles []string
+	for _, fname := range pass.OtherFiles {
+		if strings.HasSuffix(fname, ".s") {
+			sfiles = append(sfiles, fname)
+		}
+	}
+
+	for _, fname := range sfiles {
+		content, tf, err := analysisutil.ReadFile(pass.Fset, fname)
+		if err != nil {
+			return nil, err
+		}
+
+		lines := strings.SplitAfter(string(content), "\n")
+		active := false
+		for lineno, line := range lines {
+			lineno++
+
+			// Ignore comments and commented-out code.
+			if i := strings.Index(line, "//"); i >= 0 {
+				line = line[:i]
+			}
+			line = strings.TrimSpace(line)
+
+			// We start checking code at a TEXT line for a frameless function.
+			if strings.HasPrefix(line, "TEXT") && strings.Contains(line, "(SB)") && strings.Contains(line, "$0") {
+				active = true
+				continue
+			}
+			if !active {
+				continue
+			}
+
+			if asmWriteBP.MatchString(line) { // clobber of BP, function is not OK
+				pass.Reportf(analysisutil.LineStart(tf, lineno), "frame pointer is clobbered before saving")
+				active = false
+				continue
+			}
+			if asmMentionBP.MatchString(line) { // any other use of BP might be a read, so function is OK
+				active = false
+				continue
+			}
+			if asmControlFlow.MatchString(line) { // give up after any branch instruction
+				active = false
+				continue
+			}
+		}
+	}
+	return nil, nil
+}