if cm.cmode != cmode {
			if cm.policy == ModeMergeStrict {
				return fmt.Errorf("counter mode clash while reading meta-data file %s: previous file had %s, new file has %s", mdf, cm.cmode.String(), cmode.String())
			}
			// In the case of a relaxed mode merge policy, upgrade
			// mode if needed.
			if cm.cmode < cmode {
				cm.cmode = cmode
			}
		}
	}
	return nil
}

func (cm *Merger) ResetModeAndGranularity() {

		t.Fatalf("unexpected clash after reset: %v", err)
	}
}

func TestBasic(t *testing.T) {
	scenarios := []struct {
		cmode         coverage.CounterMode
		cgran         coverage.CounterGranularity
		src, dst, res []uint32
		iters         int
		merr          bool
		overflow      bool
	}{
		{
			cmode:    coverage.CtrModeSet,
			cgran:    coverage.CtrGranularityPerBlock,
			src:      []uint32{1, 0, 1},

// ProcessCoverTestDir is called from
// testmain code when "go test -cover" is in effect. It is not
// intended to be used other than internally by the Go command's
// generated code.
func ProcessCoverTestDir(dir string, cfile string, cm string, cpkg string, w io.Writer) error {
	cmode := coverage.ParseCounterMode(cm)
	if cmode == coverage.CtrModeInvalid {
		return fmt.Errorf("invalid counter mode %q", cm)
	}

	// Emit meta-data and counter data.

	}
	ml := rtcov.Meta.List
	return writeMetaData(w, ml, cmode, cgran, finalHash)
}

// WriteCountersDir implements [runtime/coverage.WriteCountersDir].
func WriteCountersDir(dir string) error {
	if cmode != coverage.CtrModeAtomic {
		return fmt.Errorf("WriteCountersDir invoked for program built with -covermode=%s (please use -covermode=atomic)", cmode.String())
	}
	return emitCounterDataToDirectory(dir)
}

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package runtime

import (
	"internal/coverage/rtcov"
	"unsafe"
)

// The compiler emits calls to runtime.addCovMeta
// but this code has moved to rtcov.AddMeta.
func addCovMeta(p unsafe.Pointer, dlen uint32, hash [16]byte, pkgpath string, pkgid int, cmode uint8, cgran uint8) uint32 {

// the process for coverage data writing (emit meta data, and register
// an exit hook to emit counter data).
func addInitHookCall(initfn *ir.Func, cmode coverage.CounterMode) {
	typecheck.InitCoverage()
	pos := initfn.Pos()
	istest := cmode == coverage.CtrModeTestMain
	initf := typecheck.LookupCoverage("initHook")
	istestNode := ir.NewBool(base.Pos, istest)
	args := []ir.Node{istestNode}

// hard-coded ID is needed), and 'cmode'/'cgran' are the coverage
// counter mode and granularity requested by the user. Return value is
// the ID for the package for use by the package code itself,
// or 0 for impossible errors.
func AddMeta(p unsafe.Pointer, dlen uint32, hash [16]byte, pkgpath string, pkgid int, cmode uint8, cgran uint8) uint32 {
	slot := len(Meta.List)

			return nil, err
		}
		tlen += uint64(entry.Len)
		ecm := coverage.CounterMode(entry.CounterMode)
		if modeClash(ecm) {
			return nil, fmt.Errorf("coverage counter mode clash: package %s uses mode=%d, but package %s uses mode=%s\n", ml[0].PkgPath, cmode, entry.PkgPath, ecm)
		}
		ecg := coverage.CounterGranularity(entry.CounterGranularity)
		if granClash(ecg) {

		if err != nil {
			return "error setting GOCOVERDIR: bad os.MkdirTemp return", err
		}
		defer os.RemoveAll(gocoverdir)
	}
	CoverMarkProfileEmittedFunc(true)
	cmode := CoverMode
	if err := CoverProcessTestDirFunc(gocoverdir, coverprofile, cmode, Covered, os.Stdout); err != nil {
		return "error generating coverage report", err
	}
	return "", nil

		Version:      coverage.MetaFileVersion,
		TotalLength:  tlen,
		Entries:      uint64(len(blobs)),
		MetaFileHash: finalHash,
		StrTabOffset: uint32(stOffset),
		StrTabLength: stSize,
		CMode:        mode,
		CGranularity: granularity,
	}
	var err error
	if err = binary.Write(m.w, binary.LittleEndian, mh); err != nil {
		return fmt.Errorf("error writing %s: %v", m.mfname, err)
	}

	if m.debug {