| // 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()) | |
| } | |