const (
	likelyDistance   = 1
	normalDistance   = 10
	unlikelyDistance = 100
)

// regalloc performs register allocation on f. It sets f.RegAlloc
// to the resulting allocation.
func regalloc(f *Func) {
	var s regAllocState
	s.init(f)
	s.regalloc(f)
	s.close()
}

type register uint8

const noRegister register = 255

// For bulk initializing

	{"schedule", "late nilcheck"},
	// flagalloc needs instructions to be scheduled.
	{"schedule", "flagalloc"},
	// regalloc needs flags to be allocated first.
	{"flagalloc", "regalloc"},
	// loopRotate will confuse regalloc.
	{"regalloc", "loop rotate"},
	// trim needs regalloc to be done first.
	{"regalloc", "trim"},
	// memcombine works better if fuse happens first, to help merge stores.
	{"late fuse", "memcombine"},

			Exit("v16"),
		),
		Bloc("b2",
			Valu("v12", OpARM64CALLstatic, types.TypeMem, 0, AuxCallLSym("_"), "v1"),
			Goto("b3"),
		),
	)
	regalloc(f.f)
	checkFunc(f.f)
	// Double-check that we never restore to the G register. Regalloc should catch it, but check again anyway.
	r := f.f.RegAlloc
	for _, b := range f.blocks {
		for _, v := range b.Values {
			if v.Op == OpLoadReg && r[v.ID].String() == "g" {

}

// deadcode removes dead code from f.
func deadcode(f *Func) {
	// deadcode after regalloc is forbidden for now. Regalloc
	// doesn't quite generate legal SSA which will lead to some
	// required moves being eliminated. See the comment at the
	// top of regalloc.go for details.
	if f.RegAlloc != nil {
		f.Fatalf("deadcode after regalloc")
	}

	// Find reachable blocks.
	reachable := ReachableBlocks(f)

	locs   [2000]Location

	// Reusable stackAllocState.
	// See stackalloc.go's {new,put}StackAllocState.
	stackAllocState *stackAllocState

	scrPoset []*poset // scratch poset to be reused

	// Reusable regalloc state.
	regallocValues []valState

	ValueToProgAfter []*obj.Prog
	debugState       debugState

	Liveness interface{} // *gc.livenessFuncCache

	// Free "headers" for use by the allocators in allocators.go.

		}
	}
}

func (f *Func) getHome(vid ID) Location {
	if int(vid) >= len(f.RegAlloc) {
		return nil
	}
	return f.RegAlloc[vid]
}

func (f *Func) setHome(v *Value, loc Location) {
	for v.ID >= ID(len(f.RegAlloc)) {
		f.RegAlloc = append(f.RegAlloc, nil)
	}
	f.RegAlloc[v.ID] = loc
}

func (s *stackAllocState) buildInterferenceGraph() {
	f := s.f

func (v *Value) Reg() int16 {
	reg := v.Block.Func.RegAlloc[v.ID]
	if reg == nil {
		v.Fatalf("nil register for value: %s\n%s\n", v.LongString(), v.Block.Func)
	}
	return reg.(*Register).objNum
}

// Reg0 returns the register assigned to the first output of v, in cmd/internal/obj/$ARCH numbering.
func (v *Value) Reg0() int16 {
	reg := v.Block.Func.RegAlloc[v.ID].(LocPair)[0]
	if reg == nil {

				continue // ok not to lower
			case OpMakeResult:
				if b.Controls[0] == v {
					continue
				}
			case OpGetG:
				if f.Config.hasGReg {
					// has hardware g register, regalloc takes care of it
					continue // ok not to lower
				}
			}
			s := "not lowered: " + v.String() + ", " + v.Op.String() + " " + v.Type.SimpleString()

			for _, a := range v.Args {

		if valueMark[v.ID] {
			f.Fatalf("used value v%d in free list", v.ID)
		}
	}

	// Check to make sure all args dominate uses.
	if f.RegAlloc == nil {
		// Note: regalloc introduces non-dominating args.
		// See TODO in regalloc.go.
		sdom := f.Sdom()
		for _, b := range f.Blocks {
			for _, v := range b.Values {
				for i, arg := range v.Args {
					x := arg.Block
					y := b

// license that can be found in the LICENSE file.

package ssa

// critical splits critical edges (those that go from a block with
// more than one outedge to a block with more than one inedge).
// Regalloc wants a critical-edge-free CFG so it can implement phi values.
func critical(f *Func) {
	// maps from phi arg ID to the new block created for that argument
	blocks := f.Cache.allocBlockSlice(f.NumValues())