runtime: make use of stringslite.{HasPrefix, HasSuffix}

Change-Id: I7461a892e1591e3bad876f0a718a99e6de2c4659
Reviewed-on: https://go-review.googlesource.com/c/go/+/585435
Reviewed-by: Michael Knyszek <mknyszek@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>

11 files changed, 33 insertions, 28 deletions

diff --git a/src/cmd/internal/objabi/pkgspecial.go b/src/cmd/internal/objabi/pkgspecial.go
index 867d92d357..6c2425d3ff 100644
--- a/src/cmd/internal/objabi/pkgspecial.go
+++ b/src/cmd/internal/objabi/pkgspecial.go
@@ -58,6 +58,7 @@ var runtimePkgs = []string{
 	"internal/godebugs",
 	"internal/goexperiment",
 	"internal/goos",
+	"internal/stringslite",
 }
 
 // extraNoInstrumentPkgs is the set of packages in addition to runtimePkgs that
diff --git a/src/runtime/export_debug_test.go b/src/runtime/export_debug_test.go
index 810a5a6435..4e0a4ef97e 100644
--- a/src/runtime/export_debug_test.go
+++ b/src/runtime/export_debug_test.go
@@ -8,6 +8,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/stringslite"
 	"unsafe"
 )
 
@@ -145,7 +146,7 @@ func (h *debugCallHandler) handle(info *siginfo, ctxt *sigctxt, gp2 *g) bool {
 		return false
 	}
 	f := findfunc(ctxt.sigpc())
-	if !(hasPrefix(funcname(f), "runtime.debugCall") || hasPrefix(funcname(f), "debugCall")) {
+	if !(stringslite.HasPrefix(funcname(f), "runtime.debugCall") || stringslite.HasPrefix(funcname(f), "debugCall")) {
 		println("trap in unknown function", funcname(f))
 		return false
 	}
diff --git a/src/runtime/os3_plan9.go b/src/runtime/os3_plan9.go
index 8c9cbe28ec..dd15705618 100644
--- a/src/runtime/os3_plan9.go
+++ b/src/runtime/os3_plan9.go
@@ -7,6 +7,7 @@ package runtime
 import (
 	"internal/abi"
 	"internal/goarch"
+	"internal/stringslite"
 	"unsafe"
 )
 
@@ -47,7 +48,7 @@ func sighandler(_ureg *ureg, note *byte, gp *g) int {
 	// level by the program but will otherwise be ignored.
 	flags = _SigNotify
 	for sig, t = range sigtable {
-		if hasPrefix(notestr, t.name) {
+		if stringslite.HasPrefix(notestr, t.name) {
 			flags = t.flags
 			break
 		}
diff --git a/src/runtime/os_plan9.go b/src/runtime/os_plan9.go
index 5e355f1664..2dbb42ad03 100644
--- a/src/runtime/os_plan9.go
+++ b/src/runtime/os_plan9.go
@@ -7,6 +7,7 @@ package runtime
 import (
 	"internal/abi"
 	"internal/runtime/atomic"
+	"internal/stringslite"
 	"unsafe"
 )
 
@@ -124,7 +125,7 @@ func indexNoFloat(s, t string) int {
 		return 0
 	}
 	for i := 0; i < len(s); i++ {
-		if s[i] == t[0] && hasPrefix(s[i:], t) {
+		if s[i] == t[0] && stringslite.HasPrefix(s[i:], t) {
 			return i
 		}
 	}
@@ -132,20 +133,20 @@ func indexNoFloat(s, t string) int {
 }
 
 func atolwhex(p string) int64 {
-	for hasPrefix(p, " ") || hasPrefix(p, "\t") {
+	for stringslite.HasPrefix(p, " ") || stringslite.HasPrefix(p, "\t") {
 		p = p[1:]
 	}
 	neg := false
-	if hasPrefix(p, "-") || hasPrefix(p, "+") {
+	if stringslite.HasPrefix(p, "-") || stringslite.HasPrefix(p, "+") {
 		neg = p[0] == '-'
 		p = p[1:]
-		for hasPrefix(p, " ") || hasPrefix(p, "\t") {
+		for stringslite.HasPrefix(p, " ") || stringslite.HasPrefix(p, "\t") {
 			p = p[1:]
 		}
 	}
 	var n int64
 	switch {
-	case hasPrefix(p, "0x"), hasPrefix(p, "0X"):
+	case stringslite.HasPrefix(p, "0x"), stringslite.HasPrefix(p, "0X"):
 		p = p[2:]
 		for ; len(p) > 0; p = p[1:] {
 			if '0' <= p[0] && p[0] <= '9' {
@@ -158,7 +159,7 @@ func atolwhex(p string) int64 {
 				break
 			}
 		}
-	case hasPrefix(p, "0"):
+	case stringslite.HasPrefix(p, "0"):
 		for ; len(p) > 0 && '0' <= p[0] && p[0] <= '7'; p = p[1:] {
 			n = n*8 + int64(p[0]-'0')
 		}
diff --git a/src/runtime/panic.go b/src/runtime/panic.go
index ff9c64113f..58d13b6adb 100644
--- a/src/runtime/panic.go
+++ b/src/runtime/panic.go
@@ -8,6 +8,7 @@ import (
 	"internal/abi"
 	"internal/goarch"
 	"internal/runtime/atomic"
+	"internal/stringslite"
 	"runtime/internal/sys"
 	"unsafe"
 )
@@ -53,7 +54,7 @@ const (
 // pc should be the program counter of the compiler-generated code that
 // triggered this panic.
 func panicCheck1(pc uintptr, msg string) {
-	if goarch.IsWasm == 0 && hasPrefix(funcname(findfunc(pc)), "runtime.") {
+	if goarch.IsWasm == 0 && stringslite.HasPrefix(funcname(findfunc(pc)), "runtime.") {
 		// Note: wasm can't tail call, so we can't get the original caller's pc.
 		throw(msg)
 	}
diff --git a/src/runtime/preempt.go b/src/runtime/preempt.go
index 82d85cd707..45b1b5e9c7 100644
--- a/src/runtime/preempt.go
+++ b/src/runtime/preempt.go
@@ -55,6 +55,7 @@ package runtime
 import (
 	"internal/abi"
 	"internal/goarch"
+	"internal/stringslite"
 )
 
 type suspendGState struct {
@@ -416,9 +417,9 @@ func isAsyncSafePoint(gp *g, pc, sp, lr uintptr) (bool, uintptr) {
 	// Check the inner-most name
 	u, uf := newInlineUnwinder(f, pc)
 	name := u.srcFunc(uf).name()
-	if hasPrefix(name, "runtime.") ||
-		hasPrefix(name, "runtime/internal/") ||
-		hasPrefix(name, "reflect.") {
+	if stringslite.HasPrefix(name, "runtime.") ||
+		stringslite.HasPrefix(name, "runtime/internal/") ||
+		stringslite.HasPrefix(name, "reflect.") {
 		// For now we never async preempt the runtime or
 		// anything closely tied to the runtime. Known issues
 		// include: various points in the scheduler ("don't
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 140f06d03d..67cd6aea78 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -10,6 +10,7 @@ import (
 	"internal/goarch"
 	"internal/goos"
 	"internal/runtime/atomic"
+	"internal/stringslite"
 	"runtime/internal/sys"
 	"unsafe"
 )
@@ -729,7 +730,7 @@ func getGodebugEarly() string {
 			p := argv_index(argv, argc+1+i)
 			s := unsafe.String(p, findnull(p))
 
-			if hasPrefix(s, prefix) {
+			if stringslite.HasPrefix(s, prefix) {
 				env = gostring(p)[len(prefix):]
 				break
 			}
@@ -5268,7 +5269,7 @@ func sigprof(pc, sp, lr uintptr, gp *g, mp *m) {
 	// received from somewhere else (with _LostSIGPROFDuringAtomic64 as pc).
 	if GOARCH == "mips" || GOARCH == "mipsle" || GOARCH == "arm" {
 		if f := findfunc(pc); f.valid() {
-			if hasPrefix(funcname(f), "internal/runtime/atomic") {
+			if stringslite.HasPrefix(funcname(f), "internal/runtime/atomic") {
 				cpuprof.lostAtomic++
 				return
 			}
diff --git a/src/runtime/security_unix.go b/src/runtime/security_unix.go
index fa54090df2..6ef3b5b328 100644
--- a/src/runtime/security_unix.go
+++ b/src/runtime/security_unix.go
@@ -6,6 +6,10 @@
 
 package runtime
 
+import (
+	"internal/stringslite"
+)
+
 func secure() {
 	initSecureMode()
 
@@ -25,7 +29,7 @@ func secure() {
 func secureEnv() {
 	var hasTraceback bool
 	for i := 0; i < len(envs); i++ {
-		if hasPrefix(envs[i], "GOTRACEBACK=") {
+		if stringslite.HasPrefix(envs[i], "GOTRACEBACK=") {
 			hasTraceback = true
 			envs[i] = "GOTRACEBACK=none"
 		}
diff --git a/src/runtime/string.go b/src/runtime/string.go
index 81d1b80e56..d45888b7a8 100644
--- a/src/runtime/string.go
+++ b/src/runtime/string.go
@@ -341,14 +341,6 @@ func gostringn(p *byte, l int) string {
 	return s
 }
 
-func hasPrefix(s, prefix string) bool {
-	return len(s) >= len(prefix) && s[:len(prefix)] == prefix
-}
-
-func hasSuffix(s, suffix string) bool {
-	return len(s) >= len(suffix) && s[len(s)-len(suffix):] == suffix
-}
-
 const (
 	maxUint64 = ^uint64(0)
 	maxInt64  = int64(maxUint64 >> 1)
diff --git a/src/runtime/symtabinl_test.go b/src/runtime/symtabinl_test.go
index df524aec4a..3c7cb2e595 100644
--- a/src/runtime/symtabinl_test.go
+++ b/src/runtime/symtabinl_test.go
@@ -6,6 +6,7 @@ package runtime
 
 import (
 	"internal/abi"
+	"internal/stringslite"
 	"runtime/internal/sys"
 )
 
@@ -50,7 +51,7 @@ func XTestInlineUnwinder(t TestingT) {
 		for ; uf.valid(); uf = u.next(uf) {
 			file, line := u.fileLine(uf)
 			const wantFile = "symtabinl_test.go"
-			if !hasSuffix(file, wantFile) {
+			if !stringslite.HasSuffix(file, wantFile) {
 				t.Errorf("tiuTest+%#x: want file ...%s, got %s", pc-pc1, wantFile, file)
 			}
 
@@ -58,10 +59,10 @@ func XTestInlineUnwinder(t TestingT) {
 
 			name := sf.name()
 			const namePrefix = "runtime."
-			if hasPrefix(name, namePrefix) {
+			if stringslite.HasPrefix(name, namePrefix) {
 				name = name[len(namePrefix):]
 			}
-			if !hasPrefix(name, "tiu") {
+			if !stringslite.HasPrefix(name, "tiu") {
 				t.Errorf("tiuTest+%#x: unexpected function %s", pc-pc1, name)
 			}
 
diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go
index 100662f274..ebee16c6a7 100644
--- a/src/runtime/traceback.go
+++ b/src/runtime/traceback.go
@@ -8,6 +8,7 @@ import (
 	"internal/abi"
 	"internal/bytealg"
 	"internal/goarch"
+	"internal/stringslite"
 	"runtime/internal/sys"
 	"unsafe"
 )
@@ -1131,7 +1132,7 @@ func showfuncinfo(sf srcFunc, firstFrame bool, calleeID abi.FuncID) bool {
 		return true
 	}
 
-	return bytealg.IndexByteString(name, '.') >= 0 && (!hasPrefix(name, "runtime.") || isExportedRuntime(name))
+	return bytealg.IndexByteString(name, '.') >= 0 && (!stringslite.HasPrefix(name, "runtime.") || isExportedRuntime(name))
 }
 
 // isExportedRuntime reports whether name is an exported runtime function.
@@ -1342,7 +1343,7 @@ func isSystemGoroutine(gp *g, fixed bool) bool {
 		}
 		return fingStatus.Load()&fingRunningFinalizer == 0
 	}
-	return hasPrefix(funcname(f), "runtime.")
+	return stringslite.HasPrefix(funcname(f), "runtime.")
 }
 
 // SetCgoTraceback records three C functions to use to gather