}

func (fwdRefAux) CanBeAnSSAAux() {}

// insertPhis finds all the places in the function where a phi is
// necessary and inserts them.
// Uses FwdRef ops to find all uses of variables, and s.defvars to find
// all definitions.
// Phi values are inserted, and all FwdRefs are changed to a Copy
// of the appropriate phi or definition.
// TODO: make this part of cmd/compile/internal/ssa somehow?
func (s *state) insertPhis() {

		}
	}
}

// phielim eliminates redundant phi values from f.
// A phi is redundant if its arguments are all equal. For
// purposes of counting, ignore the phi itself. Both of
// these phis are redundant:
//
//	v = phi(x,x,x)
//	v = phi(x,v,x,v)
//
// We repeat this process to also catch situations like:
//
//	v = phi(x, phi(x, x), phi(x, v))
//
// TODO: Can we also simplify cases like:
//

				s.Pos = s.Pos.WithIsStmt()
			}
		}
		// If `s` had more than one predecessor, update its phi-ops to
		// account for the merge.
		if ns > 1 {
			for _, v := range s.Values {
				if v.Op == OpPhi {
					mergePhi(v, j, b)
				}

			}
			// Remove the phi-ops from `b` if they were merged into the
			// phi-ops of `s`.
			k := 0
			for _, v := range b.Values {
				if v.Op == OpPhi {
					if v.Uses == 0 {

		for i := 0; i < len(b.Values); i++ {
			phi := b.Values[i]
			if phi.Uses == 0 || phi == ctl || phi.Op != OpPhi {
				continue
			}
			fixPhi(phi, i)
			if phi.Block == b {
				continue
			}
			// phi got moved to a different block with v.moveTo.
			// Adjust phi values in this new block that refer
			// to phi to refer to the corresponding phi arg instead.
			// phi used to be evaluated prior to this block,

			continue
		}

		var phi *Value
		// determine if we've only got a single phi in this
		// block, this is easier to handle than the general
		// case of a block with multiple phi values.
		for _, v := range b.Values {
			if v.Op == OpPhi {
				if phi != nil {
					phi = nil
					break
				}
				phi = v
			}
		}

		// reset our block map
		if phi != nil {
			for _, v := range phi.Args {

				}
				if fun.values["phi"].Op != OpCondSelect {
					t.Fatalf("expected phi op to be CondSelect; found op %s", fun.values["phi"].Op)
				}
				if fun.values["phi"].Args[2] != fun.values["cond"] {
					t.Errorf("expected CondSelect condition to be %s; found %s", fun.values["cond"], fun.values["phi"].Args[2])
				}
				if fun.blocks["entry"].Kind != BlockExit {

func (s sorted) max() float64 {
	if len(s) == 0 {
		return infinity
	}

	return s[len(s)-1]
}

func (s sorted) quantile(phi float64) float64 {
	if len(s) == 0 || math.IsNaN(phi) {
		return nan
	}
	if phi <= 0 {
		return s.min()
	}
	if phi >= 1 {
		return s.max()
	}
	idx := uint(phi*float64(len(s)-1) + 0.5)
	if idx >= uint(len(s)) {
		idx = uint(len(s) - 1)
	}
	return s[idx]
}

	// Insert phi functions as necessary for future changes to flow graph.
	for i, emc := range tofixBackedges {
		e := emc.e
		h := e.b

		// find the phi function for the memory input at "h", if there is one.
		var headerMemPhi *Value // look for header mem phi

		for _, v := range h.Values {
			if v.Op == OpPhi && v.Type.IsMemory() {
				headerMemPhi = v
			}
		}

		if headerMemPhi == nil {

	// Adjust c.Preds
	c.removePred(j)

	// Remove phi args from c's phis.
	for _, v := range c.Values {
		if v.Op != OpPhi {
			continue
		}
		c.removePhiArg(v, j)
		// Note: this is trickier than it looks. Replacing
		// a Phi with a Copy can in general cause problems because
		// Phi and Copy don't have exactly the same semantics.
		// Phi arguments always come from a predecessor block,

		b.Fatalf("inconsistent state for %v, num predecessors: %d, num phi args: %d", phi, n, numPhiArgs)
	}
	phi.Args[i].Uses--
	phi.Args[i] = phi.Args[n]
	phi.Args[n] = nil
	phi.Args = phi.Args[:n]
	phielimValue(phi)
}

// LackingPos indicates whether b is a block whose position should be inherited
// from its successors.  This is true if all the values within it have unreliable positions