// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package ssa

import (
	"cmd/internal/obj"
	"cmd/internal/obj/s390x"
	"cmd/internal/obj/x86"
	"cmd/internal/src"
	"testing"
)

var CheckFunc = checkFunc
var Opt = opt
var Deadcode = deadcode
var Copyelim = copyelim

var testCtxts = map[string]*obj.Link{
	"amd64": obj.Linknew(&x86.Linkamd64),
	"s390x": obj.Linknew(&s390x.Links390x),
}

func testConfig(tb testing.TB) *Conf      { return testConfigArch(tb, "amd64") }
func testConfigS390X(tb testing.TB) *Conf { return testConfigArch(tb, "s390x") }

func testConfigArch(tb testing.TB, arch string) *Conf {
	ctxt, ok := testCtxts[arch]
	if !ok {
		tb.Fatalf("unknown arch %s", arch)
	}
	if ctxt.Arch.IntSize != 8 {
		tb.Fatal("dummyTypes is 64-bit only")
	}
	c := &Conf{
		config: NewConfig(arch, dummyTypes, ctxt, true),
		tb:     tb,
	}
	return c
}

type Conf struct {
	config *Config
	tb     testing.TB
	fe     Frontend
}

func (c *Conf) Frontend() Frontend {
	if c.fe == nil {
		c.fe = DummyFrontend{t: c.tb, ctxt: c.config.ctxt}
	}
	return c.fe
}

// DummyFrontend is a test-only frontend.
// It assumes 64 bit integers and pointers.
type DummyFrontend struct {
	t    testing.TB
	ctxt *obj.Link
}

type DummyAuto struct {
	t Type
	s string
}

func (d *DummyAuto) Typ() Type {
	return d.t
}

func (d *DummyAuto) String() string {
	return d.s
}

func (DummyFrontend) StringData(s string) interface{} {
	return nil
}
func (DummyFrontend) Auto(pos src.XPos, t Type) GCNode {
	return &DummyAuto{t: t, s: "aDummyAuto"}
}
func (d DummyFrontend) SplitString(s LocalSlot) (LocalSlot, LocalSlot) {
	return LocalSlot{s.N, dummyTypes.BytePtr, s.Off}, LocalSlot{s.N, dummyTypes.Int, s.Off + 8}
}
func (d DummyFrontend) SplitInterface(s LocalSlot) (LocalSlot, LocalSlot) {
	return LocalSlot{s.N, dummyTypes.BytePtr, s.Off}, LocalSlot{s.N, dummyTypes.BytePtr, s.Off + 8}
}
func (d DummyFrontend) SplitSlice(s LocalSlot) (LocalSlot, LocalSlot, LocalSlot) {
	return LocalSlot{s.N, s.Type.ElemType().PtrTo(), s.Off},
		LocalSlot{s.N, dummyTypes.Int, s.Off + 8},
		LocalSlot{s.N, dummyTypes.Int, s.Off + 16}
}
func (d DummyFrontend) SplitComplex(s LocalSlot) (LocalSlot, LocalSlot) {
	if s.Type.Size() == 16 {
		return LocalSlot{s.N, dummyTypes.Float64, s.Off}, LocalSlot{s.N, dummyTypes.Float64, s.Off + 8}
	}
	return LocalSlot{s.N, dummyTypes.Float32, s.Off}, LocalSlot{s.N, dummyTypes.Float32, s.Off + 4}
}
func (d DummyFrontend) SplitInt64(s LocalSlot) (LocalSlot, LocalSlot) {
	if s.Type.IsSigned() {
		return LocalSlot{s.N, dummyTypes.Int32, s.Off + 4}, LocalSlot{s.N, dummyTypes.UInt32, s.Off}
	}
	return LocalSlot{s.N, dummyTypes.UInt32, s.Off + 4}, LocalSlot{s.N, dummyTypes.UInt32, s.Off}
}
func (d DummyFrontend) SplitStruct(s LocalSlot, i int) LocalSlot {
	return LocalSlot{s.N, s.Type.FieldType(i), s.Off + s.Type.FieldOff(i)}
}
func (d DummyFrontend) SplitArray(s LocalSlot) LocalSlot {
	return LocalSlot{s.N, s.Type.ElemType(), s.Off}
}
func (DummyFrontend) Line(_ src.XPos) string {
	return "unknown.go:0"
}
func (DummyFrontend) AllocFrame(f *Func) {
}
func (d DummyFrontend) Syslook(s string) *obj.LSym {
	return d.ctxt.Lookup(s)
}
func (DummyFrontend) UseWriteBarrier() bool {
	return true // only writebarrier_test cares
}

func (d DummyFrontend) Logf(msg string, args ...interface{}) { d.t.Logf(msg, args...) }
func (d DummyFrontend) Log() bool                            { return true }

func (d DummyFrontend) Fatalf(_ src.XPos, msg string, args ...interface{}) { d.t.Fatalf(msg, args...) }
func (d DummyFrontend) Warnl(_ src.XPos, msg string, args ...interface{})  { d.t.Logf(msg, args...) }
func (d DummyFrontend) Debug_checknil() bool                               { return false }
func (d DummyFrontend) Debug_wb() bool                                     { return false }

var dummyTypes = Types{
	Bool:       TypeBool,
	Int8:       TypeInt8,
	Int16:      TypeInt16,
	Int32:      TypeInt32,
	Int64:      TypeInt64,
	UInt8:      TypeUInt8,
	UInt16:     TypeUInt16,
	UInt32:     TypeUInt32,
	UInt64:     TypeUInt64,
	Float32:    TypeFloat32,
	Float64:    TypeFloat64,
	Int:        TypeInt64,
	Uintptr:    TypeUInt64,
	String:     nil,
	BytePtr:    TypeBytePtr,
	Int32Ptr:   TypeInt32.PtrTo(),
	UInt32Ptr:  TypeUInt32.PtrTo(),
	IntPtr:     TypeInt64.PtrTo(),
	UintptrPtr: TypeUInt64.PtrTo(),
	Float32Ptr: TypeFloat32.PtrTo(),
	Float64Ptr: TypeFloat64.PtrTo(),
	BytePtrPtr: TypeBytePtr.PtrTo(),
}

func (d DummyFrontend) DerefItab(sym *obj.LSym, off int64) *obj.LSym { return nil }

func (d DummyFrontend) CanSSA(t Type) bool {
	// There are no un-SSAable types in dummy land.
	return true
}