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

package ssa

// combine copyelim and phielim into a single pass.
// copyelim removes all uses of OpCopy values from f.
// A subsequent deadcode pass is needed to actually remove the copies.
func copyelim(f *Func) {
	phielim(f)

	// loop of copyelimValue(v) process has been done in phielim() pass.
	// Update block control values.
	for _, b := range f.Blocks {

		addlibpath(ctxt, "command line", "command line", flag.Arg(0), "main", "", zerofp)
	}
	bench.Start("loadlib")
	ctxt.loadlib()

	bench.Start("inittasks")
	ctxt.inittasks()

	bench.Start("deadcode")
	deadcode(ctxt)

	bench.Start("linksetup")
	ctxt.linksetup()

	bench.Start("dostrdata")
	ctxt.dostrdata()
	if buildcfg.Experiment.FieldTrack {
		bench.Start("fieldtrack")

//    iff tpose(x) or tpose(y) has one use and have same permutation.
//
// Proof:
// WLOG, let tpose(x) have 1 use. Then ewise is the only user, and removing
// its use of tpose(x) will render tpose(x) deadcode. So in this case
// we both remove 1 and add 1 transpose to the graph thus the number remains
// unchanged.
class CommuteBothInputsTransposedWithEwiseOps : public RewritePattern {
 public:

			for line, errList := range filemap {
				for _, err := range errList {
					t.Errorf("%s:%d:%d: %s", filename, line, err.col, err.text)
				}
			}
		}
	}
}

func readCode(err Error) errors.Code {
	v := reflect.ValueOf(err)
	return errors.Code(v.FieldByName("go116code").Int())
}

// boolFieldAddr(conf, name) returns the address of the boolean field conf.<name>.

}

func TestVet(t *testing.T) {
	t.Parallel()
	for _, pkg := range []string{
		"appends",
		"asm",
		"assign",
		"atomic",
		"bool",
		"buildtag",
		"cgo",
		"composite",
		"copylock",
		"deadcode",
		"directive",
		"httpresponse",
		"lostcancel",
		"method",
		"nilfunc",
		"print",
		"shift",
		"slog",
		"structtag",
		"testingpkg",
		// "testtag" has its own test
		"unmarshal",

	for _, ln := range fn.Dcl {
		if ln.OpenDeferSlot() {
			// Open-coded defer slots have indices that were assigned
			// upfront during SSA construction, but the defer statement can
			// later get removed during deadcode elimination (#61895). To
			// keep their relative offsets correct, treat them all as used.
			continue
		}

		if needAlloc(ln) {
			ln.SetUsed(false)
		}
	}

	for _, l := range f.RegAlloc {

	}
}

// rewireSuccessor rewires corresponding successors according to constant value
// discovered by previous analysis. As the result, some successors become unreachable
// and thus can be removed in further deadcode phase
func rewireSuccessor(block *Block, constVal *Value) bool {
	switch block.Kind {
	case BlockIf:
		block.removeEdge(int(constVal.AuxInt))
		block.Kind = BlockPlain
		block.Likely = BranchUnknown

)

type deadValueChoice bool

const (
	leaveDeadValues  deadValueChoice = false
	removeDeadValues                 = true
)

// deadcode indicates whether rewrite should try to remove any values that become dead.
func applyRewrite(f *Func, rb blockRewriter, rv valueRewriter, deadcode deadValueChoice) {
	// repeat rewrites until we find no more rewrites

	// true if closure inside a function; false if a simple function or a
	// closure in a global variable initialization
	funcIsHiddenClosure
	funcIsDeadcodeClosure        // true if closure is deadcode
	funcHasDefer                 // contains a defer statement
	funcNilCheckDisabled         // disable nil checks when compiling this function

// appears on panic path)
//
// 2) adjustments that take into account specific interesting values
// passed at a call site (ex: passing a constant that could result in
// cprop/deadcode in the caller)
//
// 3) adjustments that take into account values returned from the call
// at a callsite (ex: call always returns the same inlinable function,
// and return value flows unmodified into an indirect call)
//