1 files changed, 78 insertions, 0 deletions
diff --git a/src/cmd/compile/internal/ir/abi.go b/src/cmd/compile/internal/ir/abi.go
new file mode 100644
index 0000000..ebe0fbf
--- /dev/null
+++ b/src/cmd/compile/internal/ir/abi.go
@@ -0,0 +1,78 @@
+// Copyright 2022 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 ir
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/internal/obj"
+)
+
+// InitLSym defines f's obj.LSym and initializes it based on the
+// properties of f. This includes setting the symbol flags and ABI and
+// creating and initializing related DWARF symbols.
+//
+// InitLSym must be called exactly once per function and must be
+// called for both functions with bodies and functions without bodies.
+// For body-less functions, we only create the LSym; for functions
+// with bodies call a helper to setup up / populate the LSym.
+func InitLSym(f *Func, hasBody bool) {
+	if f.LSym != nil {
+		base.FatalfAt(f.Pos(), "InitLSym called twice on %v", f)
+	}
+
+	if nam := f.Nname; !IsBlank(nam) {
+		f.LSym = nam.LinksymABI(f.ABI)
+		if f.Pragma&Systemstack != 0 {
+			f.LSym.Set(obj.AttrCFunc, true)
+		}
+	}
+	if hasBody {
+		setupTextLSym(f, 0)
+	}
+}
+
+// setupTextLSym initializes the LSym for a with-body text symbol.
+func setupTextLSym(f *Func, flag int) {
+	if f.Dupok() {
+		flag |= obj.DUPOK
+	}
+	if f.Wrapper() {
+		flag |= obj.WRAPPER
+	}
+	if f.ABIWrapper() {
+		flag |= obj.ABIWRAPPER
+	}
+	if f.Needctxt() {
+		flag |= obj.NEEDCTXT
+	}
+	if f.Pragma&Nosplit != 0 {
+		flag |= obj.NOSPLIT
+	}
+	if f.IsPackageInit() {
+		flag |= obj.PKGINIT
+	}
+
+	// Clumsy but important.
+	// For functions that could be on the path of invoking a deferred
+	// function that can recover (runtime.reflectcall, reflect.callReflect,
+	// and reflect.callMethod), we want the panic+recover special handling.
+	// See test/recover.go for test cases and src/reflect/value.go
+	// for the actual functions being considered.
+	//
+	// runtime.reflectcall is an assembly function which tailcalls
+	// WRAPPER functions (runtime.callNN). Its ABI wrapper needs WRAPPER
+	// flag as well.
+	fnname := f.Sym().Name
+	if base.Ctxt.Pkgpath == "runtime" && fnname == "reflectcall" {
+		flag |= obj.WRAPPER
+	} else if base.Ctxt.Pkgpath == "reflect" {
+		switch fnname {
+		case "callReflect", "callMethod":
+			flag |= obj.WRAPPER
+		}
+	}
+
+	base.Ctxt.InitTextSym(f.LSym, flag, f.Pos())
+}