From 01a1eaa10c95dbbb1decad79334a2d6f34dc6832 Mon Sep 17 00:00:00 2001 From: Keith Randall Date: Fri, 7 Dec 2018 10:00:36 -0800 Subject: cmd/compile: use innermost line number for -S When functions are inlined, for instructions in the inlined body, does -S print the location of the call, or the location of the body? Right now, we do the former. I'd like to do the latter by default, it makes much more sense when reading disassembly. With mid-stack inlining enabled in more cases, this quandry will come up more often. The original behavior is still available with -S=2. Some tests use this mode (so they can find assembly generated by a particular source line). This helped me with understanding what the compiler was doing while fixing #29007. Change-Id: Id14a3a41e1b18901e7c5e460aa4caf6d940ed064 Reviewed-on: https://go-review.googlesource.com/c/153241 Reviewed-by: David Chase --- src/cmd/internal/obj/link.go | 2 +- src/cmd/internal/obj/objfile.go | 10 ++++++++-- src/cmd/internal/obj/plist.go | 2 +- src/cmd/internal/obj/util.go | 15 ++++++++++++++- 4 files changed, 24 insertions(+), 5 deletions(-) (limited to 'src/cmd/internal/obj') diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go index 6cff335ddf..dfecdfbb37 100644 --- a/src/cmd/internal/obj/link.go +++ b/src/cmd/internal/obj/link.go @@ -599,7 +599,7 @@ type Pcdata struct { type Link struct { Headtype objabi.HeadType Arch *LinkArch - Debugasm bool + Debugasm int Debugvlog bool Debugpcln string Flag_shared bool diff --git a/src/cmd/internal/obj/objfile.go b/src/cmd/internal/obj/objfile.go index 4fbaafe347..49301f04d5 100644 --- a/src/cmd/internal/obj/objfile.go +++ b/src/cmd/internal/obj/objfile.go @@ -240,7 +240,13 @@ func (w *objWriter) writeSymDebug(s *LSym) { fmt.Fprintf(ctxt.Bso, "\n") if s.Type == objabi.STEXT { for p := s.Func.Text; p != nil; p = p.Link { - fmt.Fprintf(ctxt.Bso, "\t%#04x %v\n", uint(int(p.Pc)), p) + var s string + if ctxt.Debugasm > 1 { + s = p.String() + } else { + s = p.InnermostString() + } + fmt.Fprintf(ctxt.Bso, "\t%#04x %s\n", uint(int(p.Pc)), s) } } for i := 0; i < len(s.P); i += 16 { @@ -283,7 +289,7 @@ func (w *objWriter) writeSymDebug(s *LSym) { func (w *objWriter) writeSym(s *LSym) { ctxt := w.ctxt - if ctxt.Debugasm { + if ctxt.Debugasm > 0 { w.writeSymDebug(s) } diff --git a/src/cmd/internal/obj/plist.go b/src/cmd/internal/obj/plist.go index 6710b375f1..9d376f739f 100644 --- a/src/cmd/internal/obj/plist.go +++ b/src/cmd/internal/obj/plist.go @@ -27,7 +27,7 @@ func Flushplist(ctxt *Link, plist *Plist, newprog ProgAlloc, myimportpath string var plink *Prog for p := plist.Firstpc; p != nil; p = plink { - if ctxt.Debugasm && ctxt.Debugvlog { + if ctxt.Debugasm > 0 && ctxt.Debugvlog { fmt.Printf("obj: %v\n", p) } plink = p.Link diff --git a/src/cmd/internal/obj/util.go b/src/cmd/internal/obj/util.go index 46c3d7b17b..f1517d3d5d 100644 --- a/src/cmd/internal/obj/util.go +++ b/src/cmd/internal/obj/util.go @@ -17,6 +17,9 @@ const REG_NONE = 0 func (p *Prog) Line() string { return p.Ctxt.OutermostPos(p.Pos).Format(false, true) } +func (p *Prog) InnermostLine() string { + return p.Ctxt.InnermostPos(p.Pos).Format(false, true) +} // InnermostLineNumber returns a string containing the line number for the // innermost inlined function (if any inlining) at p's position @@ -118,6 +121,16 @@ func (p *Prog) String() string { return fmt.Sprintf("%.5d (%v)\t%s", p.Pc, p.Line(), p.InstructionString()) } +func (p *Prog) InnermostString() string { + if p == nil { + return "" + } + if p.Ctxt == nil { + return "" + } + return fmt.Sprintf("%.5d (%v)\t%s", p.Pc, p.InnermostLine(), p.InstructionString()) +} + // InstructionString returns a string representation of the instruction without preceding // program counter or file and line number. func (p *Prog) InstructionString() string { @@ -177,7 +190,7 @@ func (ctxt *Link) NewProg() *Prog { } func (ctxt *Link) CanReuseProgs() bool { - return !ctxt.Debugasm + return ctxt.Debugasm == 0 } func Dconv(p *Prog, a *Addr) string { -- cgit v1.3