[dev.link] cmd/{compile,link}: split SDWARFINFO symtype into sub-types
This change splits the SDWARFINFO symbol type (a generic container of
DWARF content) into separate sub-classes. The new symbol types are
SDWARFCUINFO comp unit DIE, also CU info and CU packagename syms
SDWARFCONST constant DIE
SDWARFFCN subprogram DIE (default and concrete)
SDWARFABSFCN abstract function DIE
SDWARFTYPE type DIE
SDWARFVAR global variable DIE
Advantage of doing this: in the linker there are several places where
we have to iterate over a symbol's relocations to pick out references
to specific classes of DWARF sub-symbols (for example, looking for all
abstract function DIEs referenced by a subprogram DIE, or looking at
all the type DIEs used in a subprogram DIE). By splitting SDWARFINFO
into parts clients can now look only at the relocation target's sym
type as opposed to having to materialize the target sym name, or do a
lookup.
Change-Id: I4e0ee3216d3c8f1a78bec3d296c01e95b3d025b5
Reviewed-on: https://go-review.googlesource.com/c/go/+/234684
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Reviewed-by: Jeremy Faller <jeremy@golang.org>
diff --git a/src/cmd/compile/internal/gc/main.go b/src/cmd/compile/internal/gc/main.go
index b258952..6e204f4 100644
--- a/src/cmd/compile/internal/gc/main.go
+++ b/src/cmd/compile/internal/gc/main.go
@@ -1488,7 +1488,7 @@
return
}
s := Ctxt.Lookup(dwarf.CUInfoPrefix + "producer." + myimportpath)
- s.Type = objabi.SDWARFINFO
+ s.Type = objabi.SDWARFCUINFO
// Sometimes (for example when building tests) we can link
// together two package main archives. So allow dups.
s.Set(obj.AttrDuplicateOK, true)
@@ -1500,7 +1500,7 @@
// compiled, so that the linker can save it in the compile unit's DIE.
func recordPackageName() {
s := Ctxt.Lookup(dwarf.CUInfoPrefix + "packagename." + myimportpath)
- s.Type = objabi.SDWARFINFO
+ s.Type = objabi.SDWARFCUINFO
// Sometimes (for example when building tests) we can link
// together two package main archives. So allow dups.
s.Set(obj.AttrDuplicateOK, true)
diff --git a/src/cmd/internal/obj/objfile.go b/src/cmd/internal/obj/objfile.go
index 5e7018e..c0194c5 100644
--- a/src/cmd/internal/obj/objfile.go
+++ b/src/cmd/internal/obj/objfile.go
@@ -205,7 +205,7 @@
}
if s.Func.dwarfInfoSym == nil {
s.Func.dwarfInfoSym = &LSym{
- Type: objabi.SDWARFINFO,
+ Type: objabi.SDWARFFCN,
}
if ctxt.Flag_locationlists {
s.Func.dwarfLocSym = &LSym{
@@ -296,7 +296,7 @@
return
}
s := ctxt.LookupInit(dwarf.ConstInfoPrefix+myimportpath, func(s *LSym) {
- s.Type = objabi.SDWARFINFO
+ s.Type = objabi.SDWARFCONST
ctxt.Data = append(ctxt.Data, s)
})
dwarf.PutIntConst(dwCtxt{ctxt}, s, ctxt.Lookup(dwarf.InfoPrefix+typename), myimportpath+"."+name, val)
@@ -422,7 +422,7 @@
// the back end.
absfn := ft.ctxt.LookupDerived(s, dwarf.InfoPrefix+s.Name+dwarf.AbstractFuncSuffix)
absfn.Set(AttrDuplicateOK, true)
- absfn.Type = objabi.SDWARFINFO
+ absfn.Type = objabi.SDWARFABSFCN
ft.ctxt.Data = append(ft.ctxt.Data, absfn)
// In the case of "late" inlining (inlines that happen during
diff --git a/src/cmd/internal/obj/objfile2.go b/src/cmd/internal/obj/objfile2.go
index c28ae56..4679bbb 100644
--- a/src/cmd/internal/obj/objfile2.go
+++ b/src/cmd/internal/obj/objfile2.go
@@ -428,7 +428,8 @@
// Most aux symbols (ex: funcdata) are not interesting--
// pick out just the DWARF ones for now.
if aux.Type != objabi.SDWARFLOC &&
- aux.Type != objabi.SDWARFINFO &&
+ aux.Type != objabi.SDWARFFCN &&
+ aux.Type != objabi.SDWARFABSFCN &&
aux.Type != objabi.SDWARFLINES &&
aux.Type != objabi.SDWARFRANGE {
return
diff --git a/src/cmd/internal/objabi/symkind.go b/src/cmd/internal/objabi/symkind.go
index 69f1528..89577e2 100644
--- a/src/cmd/internal/objabi/symkind.go
+++ b/src/cmd/internal/objabi/symkind.go
@@ -56,7 +56,12 @@
// Thread-local data that is initially all 0s
STLSBSS
// Debugging data
- SDWARFINFO
+ SDWARFCUINFO
+ SDWARFCONST
+ SDWARFFCN
+ SDWARFABSFCN
+ SDWARFTYPE
+ SDWARFVAR
SDWARFRANGE
SDWARFLOC
SDWARFLINES
diff --git a/src/cmd/internal/objabi/symkind_string.go b/src/cmd/internal/objabi/symkind_string.go
index 919a666..1b1c394 100644
--- a/src/cmd/internal/objabi/symkind_string.go
+++ b/src/cmd/internal/objabi/symkind_string.go
@@ -16,17 +16,22 @@
_ = x[SBSS-5]
_ = x[SNOPTRBSS-6]
_ = x[STLSBSS-7]
- _ = x[SDWARFINFO-8]
- _ = x[SDWARFRANGE-9]
- _ = x[SDWARFLOC-10]
- _ = x[SDWARFLINES-11]
- _ = x[SABIALIAS-12]
- _ = x[SLIBFUZZER_EXTRA_COUNTER-13]
+ _ = x[SDWARFCUINFO-8]
+ _ = x[SDWARFCONST-9]
+ _ = x[SDWARFFCN-10]
+ _ = x[SDWARFABSFCN-11]
+ _ = x[SDWARFTYPE-12]
+ _ = x[SDWARFVAR-13]
+ _ = x[SDWARFRANGE-14]
+ _ = x[SDWARFLOC-15]
+ _ = x[SDWARFLINES-16]
+ _ = x[SABIALIAS-17]
+ _ = x[SLIBFUZZER_EXTRA_COUNTER-18]
}
-const _SymKind_name = "SxxxSTEXTSRODATASNOPTRDATASDATASBSSSNOPTRBSSSTLSBSSSDWARFINFOSDWARFRANGESDWARFLOCSDWARFLINESSABIALIASSLIBFUZZER_EXTRA_COUNTER"
+const _SymKind_name = "SxxxSTEXTSRODATASNOPTRDATASDATASBSSSNOPTRBSSSTLSBSSSDWARFCUINFOSDWARFCONSTSDWARFFCNSDWARFABSFCNSDWARFTYPESDWARFVARSDWARFRANGESDWARFLOCSDWARFLINESSABIALIASSLIBFUZZER_EXTRA_COUNTER"
-var _SymKind_index = [...]uint8{0, 4, 9, 16, 26, 31, 35, 44, 51, 61, 72, 81, 92, 101, 125}
+var _SymKind_index = [...]uint8{0, 4, 9, 16, 26, 31, 35, 44, 51, 63, 74, 83, 95, 105, 114, 125, 134, 145, 154, 178}
func (i SymKind) String() string {
if i >= SymKind(len(_SymKind_index)-1) {
diff --git a/src/cmd/link/internal/ld/dwarf.go b/src/cmd/link/internal/ld/dwarf.go
index 18fcdbd..912494b 100644
--- a/src/cmd/link/internal/ld/dwarf.go
+++ b/src/cmd/link/internal/ld/dwarf.go
@@ -277,24 +277,37 @@
newattr(die, dwarf.DW_AT_name, dwarf.DW_CLS_STRING, int64(len(name)), name)
- if name != "" && (abbrev <= dwarf.DW_ABRV_VARIABLE || abbrev >= dwarf.DW_ABRV_NULLTYPE) {
- // Q: do we need version here? My understanding is that all these
- // symbols should be version 0.
- if abbrev != dwarf.DW_ABRV_VARIABLE || version == 0 {
- if abbrev == dwarf.DW_ABRV_COMPUNIT {
- // Avoid collisions with "real" symbol names.
- name = fmt.Sprintf(".pkg.%s.%d", name, len(d.linkctxt.compUnits))
- }
- ds := d.ldr.LookupOrCreateSym(dwarf.InfoPrefix+name, version)
- dsu := d.ldr.MakeSymbolUpdater(ds)
- dsu.SetType(sym.SDWARFINFO)
- d.ldr.SetAttrNotInSymbolTable(ds, true)
- d.ldr.SetAttrReachable(ds, true)
- die.Sym = dwSym(ds)
- if abbrev >= dwarf.DW_ABRV_NULLTYPE && abbrev <= dwarf.DW_ABRV_TYPEDECL {
- d.tmap[name] = ds
- }
- }
+ // Sanity check: all DIEs created in the linker should have a non-empty
+ // name and be version zero.
+ if name == "" || version != 0 {
+ panic("nameless or version non-zero DWARF DIE")
+ }
+
+ var st sym.SymKind
+ switch abbrev {
+ case dwarf.DW_ABRV_FUNCTYPEPARAM, dwarf.DW_ABRV_DOTDOTDOT, dwarf.DW_ABRV_STRUCTFIELD, dwarf.DW_ABRV_ARRAYRANGE:
+ // There are no relocations against these dies, and their names
+ // are not unique, so don't create a symbol.
+ return die
+ case dwarf.DW_ABRV_COMPUNIT, dwarf.DW_ABRV_COMPUNIT_TEXTLESS:
+ // Avoid collisions with "real" symbol names.
+ name = fmt.Sprintf(".pkg.%s.%d", name, len(d.linkctxt.compUnits))
+ st = sym.SDWARFCUINFO
+ case dwarf.DW_ABRV_VARIABLE:
+ st = sym.SDWARFVAR
+ default:
+ // Everything else is assigned a type of SDWARFTYPE. that
+ // this also includes loose ends such as STRUCT_FIELD.
+ st = sym.SDWARFTYPE
+ }
+ ds := d.ldr.LookupOrCreateSym(dwarf.InfoPrefix+name, version)
+ dsu := d.ldr.MakeSymbolUpdater(ds)
+ dsu.SetType(st)
+ d.ldr.SetAttrNotInSymbolTable(ds, true)
+ d.ldr.SetAttrReachable(ds, true)
+ die.Sym = dwSym(ds)
+ if abbrev >= dwarf.DW_ABRV_NULLTYPE && abbrev <= dwarf.DW_ABRV_TYPEDECL {
+ d.tmap[name] = ds
}
return die
@@ -480,7 +493,7 @@
// to be an anonymous symbol (we want this for perf reasons).
tds := d.ldr.CreateExtSym("", 0)
tdsu := d.ldr.MakeSymbolUpdater(tds)
- tdsu.SetType(sym.SDWARFINFO)
+ tdsu.SetType(sym.SDWARFTYPE)
def.Sym = dwSym(tds)
d.ldr.SetAttrNotInSymbolTable(tds, true)
d.ldr.SetAttrReachable(tds, true)
@@ -850,7 +863,7 @@
name := mkinternaltypename(typename, keyname, valname)
symname := dwarf.InfoPrefix + name
s := d.ldr.Lookup(symname, 0)
- if s != 0 && d.ldr.SymType(s) == sym.SDWARFINFO {
+ if s != 0 && d.ldr.SymType(s) == sym.SDWARFTYPE {
return s
}
die := d.newdie(&dwtypes, abbrev, name, 0)
@@ -1122,7 +1135,8 @@
func (d *dwctxt) importInfoSymbol(ctxt *Link, dsym loader.Sym) {
d.ldr.SetAttrReachable(dsym, true)
d.ldr.SetAttrNotInSymbolTable(dsym, true)
- if d.ldr.SymType(dsym) != sym.SDWARFINFO {
+ dst := d.ldr.SymType(dsym)
+ if dst != sym.SDWARFCONST && dst != sym.SDWARFABSFCN {
log.Fatalf("error: DWARF info sym %d/%s with incorrect type %s", dsym, d.ldr.SymName(dsym), d.ldr.SymType(dsym).String())
}
relocs := d.ldr.Relocs(dsym)
@@ -1492,7 +1506,7 @@
infosec := d.ldr.LookupOrCreateSym(".debug_info", 0)
disu := d.ldr.MakeSymbolUpdater(infosec)
- disu.SetType(sym.SDWARFINFO)
+ disu.SetType(sym.SDWARFCUINFO)
d.ldr.SetAttrReachable(infosec, true)
syms := []loader.Sym{infosec}
@@ -1814,7 +1828,11 @@
ctxt.runtimeCU = unit
}
- unit.DWInfo = d.newdie(&dwroot, dwarf.DW_ABRV_COMPUNIT, unit.Lib.Pkg, 0)
+ cuabrv := dwarf.DW_ABRV_COMPUNIT
+ if len(unit.Textp) == 0 {
+ cuabrv = dwarf.DW_ABRV_COMPUNIT_TEXTLESS
+ }
+ unit.DWInfo = d.newdie(&dwroot, cuabrv, unit.Lib.Pkg, 0)
newattr(unit.DWInfo, dwarf.DW_AT_language, dwarf.DW_CLS_CONSTANT, int64(dwarf.DW_LANG_Go), 0)
// OS X linker requires compilation dir or absolute path in comp unit name to output debug info.
compDir := getCompilationDir()
@@ -1850,10 +1868,6 @@
}
newattr(unit.DWInfo, dwarf.DW_AT_go_package_name, dwarf.DW_CLS_STRING, int64(len(pkgname)), pkgname)
- if len(unit.Textp) == 0 {
- unit.DWInfo.Abbrev = dwarf.DW_ABRV_COMPUNIT_TEXTLESS
- }
-
// Scan all functions in this compilation unit, create DIEs for all
// referenced types, create the file table for debug_line, find all
// referenced abstract functions.
diff --git a/src/cmd/link/internal/loader/loader.go b/src/cmd/link/internal/loader/loader.go
index 38c4e6e..1917876 100644
--- a/src/cmd/link/internal/loader/loader.go
+++ b/src/cmd/link/internal/loader/loader.go
@@ -1539,7 +1539,7 @@
switch a.Type() {
case goobj2.AuxDwarfInfo:
auxDwarfInfo = l.resolve(r, a.Sym())
- if l.SymType(auxDwarfInfo) != sym.SDWARFINFO {
+ if l.SymType(auxDwarfInfo) != sym.SDWARFFCN {
panic("aux dwarf info sym with wrong type")
}
case goobj2.AuxDwarfLoc:
@@ -2105,7 +2105,7 @@
return true
}
switch skind {
- case sym.SDWARFINFO, sym.SDWARFRANGE, sym.SDWARFLOC, sym.SDWARFLINES, sym.SGOFUNC:
+ case sym.SDWARFFCN, sym.SDWARFABSFCN, sym.SDWARFTYPE, sym.SDWARFCONST, sym.SDWARFCUINFO, sym.SDWARFRANGE, sym.SDWARFLOC, sym.SDWARFLINES, sym.SGOFUNC:
return true
default:
return false
diff --git a/src/cmd/link/internal/sym/symkind.go b/src/cmd/link/internal/sym/symkind.go
index 75f72c3..e4a8fe7 100644
--- a/src/cmd/link/internal/sym/symkind.go
+++ b/src/cmd/link/internal/sym/symkind.go
@@ -108,7 +108,13 @@
// Sections for debugging information
SDWARFSECT
- SDWARFINFO
+ // DWARF symbol types
+ SDWARFCUINFO
+ SDWARFCONST
+ SDWARFFCN
+ SDWARFABSFCN
+ SDWARFTYPE
+ SDWARFVAR
SDWARFRANGE
SDWARFLOC
SDWARFLINES
@@ -128,7 +134,12 @@
SBSS,
SNOPTRBSS,
STLSBSS,
- SDWARFINFO,
+ SDWARFCUINFO,
+ SDWARFCONST,
+ SDWARFFCN,
+ SDWARFABSFCN,
+ SDWARFTYPE,
+ SDWARFVAR,
SDWARFRANGE,
SDWARFLOC,
SDWARFLINES,
diff --git a/src/cmd/link/internal/sym/symkind_string.go b/src/cmd/link/internal/sym/symkind_string.go
index 5777047..47b2406 100644
--- a/src/cmd/link/internal/sym/symkind_string.go
+++ b/src/cmd/link/internal/sym/symkind_string.go
@@ -1,4 +1,4 @@
-// Code generated by "stringer -type=SymKind"; DO NOT EDIT.
+// Code generated by "stringer -type=SymKindstringer -type=SymKind"; DO NOT EDIT.
package sym
@@ -56,16 +56,21 @@
_ = x[SHOSTOBJ-45]
_ = x[SUNDEFEXT-46]
_ = x[SDWARFSECT-47]
- _ = x[SDWARFINFO-48]
- _ = x[SDWARFRANGE-49]
- _ = x[SDWARFLOC-50]
- _ = x[SDWARFLINES-51]
- _ = x[SABIALIAS-52]
+ _ = x[SDWARFCUINFO-48]
+ _ = x[SDWARFCONST-49]
+ _ = x[SDWARFFCN-50]
+ _ = x[SDWARFABSFCN-51]
+ _ = x[SDWARFTYPE-52]
+ _ = x[SDWARFVAR-53]
+ _ = x[SDWARFRANGE-54]
+ _ = x[SDWARFLOC-55]
+ _ = x[SDWARFLINES-56]
+ _ = x[SABIALIAS-57]
}
-const _SymKind_name = "SxxxSTEXTSELFRXSECTSTYPESSTRINGSGOSTRINGSGOFUNCSGCBITSSRODATASFUNCTABSELFROSECTSMACHOPLTSTYPERELROSSTRINGRELROSGOSTRINGRELROSGOFUNCRELROSGCBITSRELROSRODATARELROSFUNCTABRELROSTYPELINKSITABLINKSSYMTABSPCLNTABSFirstWritableSBUILDINFOSELFSECTSMACHOSMACHOGOTSWINDOWSSELFGOTSNOPTRDATASINITARRSDATASXCOFFTOCSBSSSNOPTRBSSSLIBFUZZER_EXTRA_COUNTERSTLSBSSSXREFSMACHOSYMSTRSMACHOSYMTABSMACHOINDIRECTPLTSMACHOINDIRECTGOTSFILEPATHSDYNIMPORTSHOSTOBJSUNDEFEXTSDWARFSECTSDWARFINFOSDWARFRANGESDWARFLOCSDWARFLINESSABIALIAS"
+const _SymKind_name = "SxxxSTEXTSELFRXSECTSTYPESSTRINGSGOSTRINGSGOFUNCSGCBITSSRODATASFUNCTABSELFROSECTSMACHOPLTSTYPERELROSSTRINGRELROSGOSTRINGRELROSGOFUNCRELROSGCBITSRELROSRODATARELROSFUNCTABRELROSTYPELINKSITABLINKSSYMTABSPCLNTABSFirstWritableSBUILDINFOSELFSECTSMACHOSMACHOGOTSWINDOWSSELFGOTSNOPTRDATASINITARRSDATASXCOFFTOCSBSSSNOPTRBSSSLIBFUZZER_EXTRA_COUNTERSTLSBSSSXREFSMACHOSYMSTRSMACHOSYMTABSMACHOINDIRECTPLTSMACHOINDIRECTGOTSFILEPATHSDYNIMPORTSHOSTOBJSUNDEFEXTSDWARFSECTSDWARFCUINFOSDWARFCONSTSDWARFFCNSDWARFABSFCNSDWARFTYPESDWARFVARSDWARFRANGESDWARFLOCSDWARFLINESSABIALIAS"
-var _SymKind_index = [...]uint16{0, 4, 9, 19, 24, 31, 40, 47, 54, 61, 69, 79, 88, 98, 110, 124, 136, 148, 160, 173, 182, 191, 198, 206, 220, 230, 238, 244, 253, 261, 268, 278, 286, 291, 300, 304, 313, 337, 344, 349, 361, 373, 390, 407, 416, 426, 434, 443, 453, 463, 474, 483, 494, 503}
+var _SymKind_index = [...]uint16{0, 4, 9, 19, 24, 31, 40, 47, 54, 61, 69, 79, 88, 98, 110, 124, 136, 148, 160, 173, 182, 191, 198, 206, 220, 230, 238, 244, 253, 261, 268, 278, 286, 291, 300, 304, 313, 337, 344, 349, 361, 373, 390, 407, 416, 426, 434, 443, 453, 465, 476, 485, 497, 507, 516, 527, 536, 547, 556}
func (i SymKind) String() string {
if i >= SymKind(len(_SymKind_index)-1) {
