Adding upstream version 1.22.1.upstream/1.22.1

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 123 insertions, 0 deletions

diff --git a/src/cmd/internal/objabi/pkgspecial.go b/src/cmd/internal/objabi/pkgspecial.go
new file mode 100644
index 0000000..6df95f3
--- /dev/null
+++ b/src/cmd/internal/objabi/pkgspecial.go
@@ -0,0 +1,123 @@
+// Copyright 2023 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 objabi
+
+import "sync"
+
+// PkgSpecial indicates special build properties of a given runtime-related
+// package.
+type PkgSpecial struct {
+	// Runtime indicates that this package is "runtime" or imported by
+	// "runtime". This has several effects (which maybe should be split out):
+	//
+	// - Implicit allocation is disallowed.
+	//
+	// - Various runtime pragmas are enabled.
+	//
+	// - Optimizations are always enabled.
+	//
+	// This should be set for runtime and all packages it imports, and may be
+	// set for additional packages.
+	Runtime bool
+
+	// NoInstrument indicates this package should not receive sanitizer
+	// instrumentation. In many of these, instrumentation could cause infinite
+	// recursion. This is all runtime packages, plus those that support the
+	// sanitizers.
+	NoInstrument bool
+
+	// NoRaceFunc indicates functions in this package should not get
+	// racefuncenter/racefuncexit instrumentation Memory accesses in these
+	// packages are either uninteresting or will cause false positives.
+	NoRaceFunc bool
+
+	// AllowAsmABI indicates that assembly in this package is allowed to use ABI
+	// selectors in symbol names. Generally this is needed for packages that
+	// interact closely with the runtime package or have performance-critical
+	// assembly.
+	AllowAsmABI bool
+}
+
+var runtimePkgs = []string{
+	"runtime",
+
+	"runtime/internal/atomic",
+	"runtime/internal/math",
+	"runtime/internal/sys",
+	"runtime/internal/syscall",
+
+	"internal/abi",
+	"internal/bytealg",
+	"internal/chacha8rand",
+	"internal/coverage/rtcov",
+	"internal/cpu",
+	"internal/goarch",
+	"internal/godebugs",
+	"internal/goexperiment",
+	"internal/goos",
+}
+
+// extraNoInstrumentPkgs is the set of packages in addition to runtimePkgs that
+// should have NoInstrument set.
+var extraNoInstrumentPkgs = []string{
+	"runtime/race",
+	"runtime/msan",
+	"runtime/asan",
+	// We omit bytealg even though it's imported by runtime because it also
+	// backs a lot of package bytes. Currently we don't have a way to omit race
+	// instrumentation when used from the runtime while keeping race
+	// instrumentation when used from user code. Somehow this doesn't seem to
+	// cause problems, though we may be skating on thin ice. See #61204.
+	"-internal/bytealg",
+}
+
+var noRaceFuncPkgs = []string{"sync", "sync/atomic"}
+
+var allowAsmABIPkgs = []string{
+	"runtime",
+	"reflect",
+	"syscall",
+	"internal/bytealg",
+	"internal/chacha8rand",
+	"runtime/internal/syscall",
+	"runtime/internal/startlinetest",
+}
+
+var (
+	pkgSpecials     map[string]PkgSpecial
+	pkgSpecialsOnce sync.Once
+)
+
+// LookupPkgSpecial returns special build properties for the given package path.
+func LookupPkgSpecial(pkgPath string) PkgSpecial {
+	pkgSpecialsOnce.Do(func() {
+		// Construct pkgSpecials from various package lists. This lets us use
+		// more flexible logic, while keeping the final map simple, and avoids
+		// the init-time cost of a map.
+		pkgSpecials = make(map[string]PkgSpecial)
+		set := func(elt string, f func(*PkgSpecial)) {
+			s := pkgSpecials[elt]
+			f(&s)
+			pkgSpecials[elt] = s
+		}
+		for _, pkg := range runtimePkgs {
+			set(pkg, func(ps *PkgSpecial) { ps.Runtime = true; ps.NoInstrument = true })
+		}
+		for _, pkg := range extraNoInstrumentPkgs {
+			if pkg[0] == '-' {
+				set(pkg[1:], func(ps *PkgSpecial) { ps.NoInstrument = false })
+			} else {
+				set(pkg, func(ps *PkgSpecial) { ps.NoInstrument = true })
+			}
+		}
+		for _, pkg := range noRaceFuncPkgs {
+			set(pkg, func(ps *PkgSpecial) { ps.NoRaceFunc = true })
+		}
+		for _, pkg := range allowAsmABIPkgs {
+			set(pkg, func(ps *PkgSpecial) { ps.AllowAsmABI = true })
+		}
+	})
+	return pkgSpecials[pkgPath]
+}