Adding upstream version 1.22.1.upstream/1.22.1

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

1 files changed, 214 insertions, 0 deletions

diff --git a/src/cmd/compile/internal/objw/prog.go b/src/cmd/compile/internal/objw/prog.go
new file mode 100644
index 0000000..84fb996
--- /dev/null
+++ b/src/cmd/compile/internal/objw/prog.go
@@ -0,0 +1,214 @@
+// Derived from Inferno utils/6c/txt.c
+// https://bitbucket.org/inferno-os/inferno-os/src/master/utils/6c/txt.c
+//
+//	Copyright © 1994-1999 Lucent Technologies Inc.  All rights reserved.
+//	Portions Copyright © 1995-1997 C H Forsyth (forsyth@terzarima.net)
+//	Portions Copyright © 1997-1999 Vita Nuova Limited
+//	Portions Copyright © 2000-2007 Vita Nuova Holdings Limited (www.vitanuova.com)
+//	Portions Copyright © 2004,2006 Bruce Ellis
+//	Portions Copyright © 2005-2007 C H Forsyth (forsyth@terzarima.net)
+//	Revisions Copyright © 2000-2007 Lucent Technologies Inc. and others
+//	Portions Copyright © 2009 The Go Authors. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+package objw
+
+import (
+	"cmd/compile/internal/base"
+	"cmd/compile/internal/ir"
+	"cmd/internal/obj"
+	"cmd/internal/src"
+	"internal/abi"
+)
+
+var sharedProgArray = new([10000]obj.Prog) // *T instead of T to work around issue 19839
+
+// NewProgs returns a new Progs for fn.
+// worker indicates which of the backend workers will use the Progs.
+func NewProgs(fn *ir.Func, worker int) *Progs {
+	pp := new(Progs)
+	if base.Ctxt.CanReuseProgs() {
+		sz := len(sharedProgArray) / base.Flag.LowerC
+		pp.Cache = sharedProgArray[sz*worker : sz*(worker+1)]
+	}
+	pp.CurFunc = fn
+
+	// prime the pump
+	pp.Next = pp.NewProg()
+	pp.Clear(pp.Next)
+
+	pp.Pos = fn.Pos()
+	pp.SetText(fn)
+	// PCDATA tables implicitly start with index -1.
+	pp.PrevLive = -1
+	pp.NextLive = pp.PrevLive
+	pp.NextUnsafe = pp.PrevUnsafe
+	return pp
+}
+
+// Progs accumulates Progs for a function and converts them into machine code.
+type Progs struct {
+	Text       *obj.Prog  // ATEXT Prog for this function
+	Next       *obj.Prog  // next Prog
+	PC         int64      // virtual PC; count of Progs
+	Pos        src.XPos   // position to use for new Progs
+	CurFunc    *ir.Func   // fn these Progs are for
+	Cache      []obj.Prog // local progcache
+	CacheIndex int        // first free element of progcache
+
+	NextLive StackMapIndex // liveness index for the next Prog
+	PrevLive StackMapIndex // last emitted liveness index
+
+	NextUnsafe bool // unsafe mark for the next Prog
+	PrevUnsafe bool // last emitted unsafe mark
+}
+
+type StackMapIndex int
+
+// StackMapDontCare indicates that the stack map index at a Value
+// doesn't matter.
+//
+// This is a sentinel value that should never be emitted to the PCDATA
+// stream. We use -1000 because that's obviously never a valid stack
+// index (but -1 is).
+const StackMapDontCare StackMapIndex = -1000
+
+func (s StackMapIndex) StackMapValid() bool {
+	return s != StackMapDontCare
+}
+
+func (pp *Progs) NewProg() *obj.Prog {
+	var p *obj.Prog
+	if pp.CacheIndex < len(pp.Cache) {
+		p = &pp.Cache[pp.CacheIndex]
+		pp.CacheIndex++
+	} else {
+		p = new(obj.Prog)
+	}
+	p.Ctxt = base.Ctxt
+	return p
+}
+
+// Flush converts from pp to machine code.
+func (pp *Progs) Flush() {
+	plist := &obj.Plist{Firstpc: pp.Text, Curfn: pp.CurFunc}
+	obj.Flushplist(base.Ctxt, plist, pp.NewProg)
+}
+
+// Free clears pp and any associated resources.
+func (pp *Progs) Free() {
+	if base.Ctxt.CanReuseProgs() {
+		// Clear progs to enable GC and avoid abuse.
+		s := pp.Cache[:pp.CacheIndex]
+		for i := range s {
+			s[i] = obj.Prog{}
+		}
+	}
+	// Clear pp to avoid abuse.
+	*pp = Progs{}
+}
+
+// Prog adds a Prog with instruction As to pp.
+func (pp *Progs) Prog(as obj.As) *obj.Prog {
+	if pp.NextLive != StackMapDontCare && pp.NextLive != pp.PrevLive {
+		// Emit stack map index change.
+		idx := pp.NextLive
+		pp.PrevLive = idx
+		p := pp.Prog(obj.APCDATA)
+		p.From.SetConst(abi.PCDATA_StackMapIndex)
+		p.To.SetConst(int64(idx))
+	}
+	if pp.NextUnsafe != pp.PrevUnsafe {
+		// Emit unsafe-point marker.
+		pp.PrevUnsafe = pp.NextUnsafe
+		p := pp.Prog(obj.APCDATA)
+		p.From.SetConst(abi.PCDATA_UnsafePoint)
+		if pp.NextUnsafe {
+			p.To.SetConst(abi.UnsafePointUnsafe)
+		} else {
+			p.To.SetConst(abi.UnsafePointSafe)
+		}
+	}
+
+	p := pp.Next
+	pp.Next = pp.NewProg()
+	pp.Clear(pp.Next)
+	p.Link = pp.Next
+
+	if !pp.Pos.IsKnown() && base.Flag.K != 0 {
+		base.Warn("prog: unknown position (line 0)")
+	}
+
+	p.As = as
+	p.Pos = pp.Pos
+	if pp.Pos.IsStmt() == src.PosIsStmt {
+		// Clear IsStmt for later Progs at this pos provided that as can be marked as a stmt
+		if LosesStmtMark(as) {
+			return p
+		}
+		pp.Pos = pp.Pos.WithNotStmt()
+	}
+	return p
+}
+
+func (pp *Progs) Clear(p *obj.Prog) {
+	obj.Nopout(p)
+	p.As = obj.AEND
+	p.Pc = pp.PC
+	pp.PC++
+}
+
+func (pp *Progs) Append(p *obj.Prog, as obj.As, ftype obj.AddrType, freg int16, foffset int64, ttype obj.AddrType, treg int16, toffset int64) *obj.Prog {
+	q := pp.NewProg()
+	pp.Clear(q)
+	q.As = as
+	q.Pos = p.Pos
+	q.From.Type = ftype
+	q.From.Reg = freg
+	q.From.Offset = foffset
+	q.To.Type = ttype
+	q.To.Reg = treg
+	q.To.Offset = toffset
+	q.Link = p.Link
+	p.Link = q
+	return q
+}
+
+func (pp *Progs) SetText(fn *ir.Func) {
+	if pp.Text != nil {
+		base.Fatalf("Progs.SetText called twice")
+	}
+	ptxt := pp.Prog(obj.ATEXT)
+	pp.Text = ptxt
+
+	fn.LSym.Func().Text = ptxt
+	ptxt.From.Type = obj.TYPE_MEM
+	ptxt.From.Name = obj.NAME_EXTERN
+	ptxt.From.Sym = fn.LSym
+}
+
+// LosesStmtMark reports whether a prog with op as loses its statement mark on the way to DWARF.
+// The attributes from some opcodes are lost in translation.
+// TODO: this is an artifact of how funcpctab combines information for instructions at a single PC.
+// Should try to fix it there.
+func LosesStmtMark(as obj.As) bool {
+	// is_stmt does not work for these; it DOES for ANOP even though that generates no code.
+	return as == obj.APCDATA || as == obj.AFUNCDATA
+}