src/cmd/6g/prog.go

// Copyright 2013 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 main

import (
	"cmd/internal/gc"
	"cmd/internal/obj"
	"cmd/internal/obj/x86"
)

var (
	AX               = RtoB(x86.REG_AX)
	BX               = RtoB(x86.REG_BX)
	CX               = RtoB(x86.REG_CX)
	DX               = RtoB(x86.REG_DX)
	DI               = RtoB(x86.REG_DI)
	SI               = RtoB(x86.REG_SI)
	LeftRdwr  uint32 = gc.LeftRead | gc.LeftWrite
	RightRdwr uint32 = gc.RightRead | gc.RightWrite
)

// This table gives the basic information about instruction
// generated by the compiler and processed in the optimizer.
// See opt.h for bit definitions.
//
// Instructions not generated need not be listed.
// As an exception to that rule, we typically write down all the
// size variants of an operation even if we just use a subset.
//
// The table is formatted for 8-space tabs.
var progtable = [x86.ALAST]gc.ProgInfo{
	obj.ATYPE:     gc.ProgInfo{gc.Pseudo | gc.Skip, 0, 0, 0},
	obj.ATEXT:     gc.ProgInfo{gc.Pseudo, 0, 0, 0},
	obj.AFUNCDATA: gc.ProgInfo{gc.Pseudo, 0, 0, 0},
	obj.APCDATA:   gc.ProgInfo{gc.Pseudo, 0, 0, 0},
	obj.AUNDEF:    gc.ProgInfo{gc.Break, 0, 0, 0},
	obj.AUSEFIELD: gc.ProgInfo{gc.OK, 0, 0, 0},
	obj.ACHECKNIL: gc.ProgInfo{gc.LeftRead, 0, 0, 0},
	obj.AVARDEF:   gc.ProgInfo{gc.Pseudo | gc.RightWrite, 0, 0, 0},
	obj.AVARKILL:  gc.ProgInfo{gc.Pseudo | gc.RightWrite, 0, 0, 0},

	// NOP is an internal no-op that also stands
	// for USED and SET annotations, not the Intel opcode.
	obj.ANOP:       gc.ProgInfo{gc.LeftRead | gc.RightWrite, 0, 0, 0},
	x86.AADCL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.AADCQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.AADCW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.AADDB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AADDL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AADDW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AADDQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AADDSD:     gc.ProgInfo{gc.SizeD | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.AADDSS:     gc.ProgInfo{gc.SizeF | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.AANDB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AANDL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AANDQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AANDW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	obj.ACALL:      gc.ProgInfo{gc.RightAddr | gc.Call | gc.KillCarry, 0, 0, 0},
	x86.ACDQ:       gc.ProgInfo{gc.OK, AX, AX | DX, 0},
	x86.ACQO:       gc.ProgInfo{gc.OK, AX, AX | DX, 0},
	x86.ACWD:       gc.ProgInfo{gc.OK, AX, AX | DX, 0},
	x86.ACLD:       gc.ProgInfo{gc.OK, 0, 0, 0},
	x86.ASTD:       gc.ProgInfo{gc.OK, 0, 0, 0},
	x86.ACMPB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACMPL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACMPQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACMPW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACOMISD:    gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACOMISS:    gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ACVTSD2SL:  gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSD2SQ:  gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSD2SS:  gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSL2SD:  gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSL2SS:  gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSQ2SD:  gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSQ2SS:  gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSS2SD:  gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSS2SL:  gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTSS2SQ:  gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTTSD2SL: gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTTSD2SQ: gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTTSS2SL: gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ACVTTSS2SQ: gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.ADECB:      gc.ProgInfo{gc.SizeB | RightRdwr, 0, 0, 0},
	x86.ADECL:      gc.ProgInfo{gc.SizeL | RightRdwr, 0, 0, 0},
	x86.ADECQ:      gc.ProgInfo{gc.SizeQ | RightRdwr, 0, 0, 0},
	x86.ADECW:      gc.ProgInfo{gc.SizeW | RightRdwr, 0, 0, 0},
	x86.ADIVB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.SetCarry, AX, AX, 0},
	x86.ADIVL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.ADIVQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.ADIVW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.ADIVSD:     gc.ProgInfo{gc.SizeD | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.ADIVSS:     gc.ProgInfo{gc.SizeF | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.AIDIVB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.SetCarry, AX, AX, 0},
	x86.AIDIVL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.AIDIVQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.AIDIVW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.SetCarry, AX | DX, AX | DX, 0},
	x86.AIMULB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.SetCarry, AX, AX, 0},
	x86.AIMULL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.ImulAXDX | gc.SetCarry, 0, 0, 0},
	x86.AIMULQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.ImulAXDX | gc.SetCarry, 0, 0, 0},
	x86.AIMULW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.ImulAXDX | gc.SetCarry, 0, 0, 0},
	x86.AINCB:      gc.ProgInfo{gc.SizeB | RightRdwr, 0, 0, 0},
	x86.AINCL:      gc.ProgInfo{gc.SizeL | RightRdwr, 0, 0, 0},
	x86.AINCQ:      gc.ProgInfo{gc.SizeQ | RightRdwr, 0, 0, 0},
	x86.AINCW:      gc.ProgInfo{gc.SizeW | RightRdwr, 0, 0, 0},
	x86.AJCC:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJCS:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJEQ:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJGE:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJGT:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJHI:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJLE:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJLS:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJLT:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJMI:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJNE:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJOC:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJOS:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJPC:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJPL:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	x86.AJPS:       gc.ProgInfo{gc.Cjmp | gc.UseCarry, 0, 0, 0},
	obj.AJMP:       gc.ProgInfo{gc.Jump | gc.Break | gc.KillCarry, 0, 0, 0},
	x86.ALEAL:      gc.ProgInfo{gc.LeftAddr | gc.RightWrite, 0, 0, 0},
	x86.ALEAQ:      gc.ProgInfo{gc.LeftAddr | gc.RightWrite, 0, 0, 0},
	x86.AMOVBLSX:   gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVBLZX:   gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVBQSX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVBQZX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVBWSX:   gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVBWZX:   gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVLQSX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVLQZX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVWLSX:   gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVWLZX:   gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVWQSX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVWQZX:   gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVQL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Conv, 0, 0, 0},
	x86.AMOVB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMOVL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMOVQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMOVW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMOVSB:     gc.ProgInfo{gc.OK, DI | SI, DI | SI, 0},
	x86.AMOVSL:     gc.ProgInfo{gc.OK, DI | SI, DI | SI, 0},
	x86.AMOVSQ:     gc.ProgInfo{gc.OK, DI | SI, DI | SI, 0},
	x86.AMOVSW:     gc.ProgInfo{gc.OK, DI | SI, DI | SI, 0},
	obj.ADUFFCOPY:  gc.ProgInfo{gc.OK, DI | SI, DI | SI | CX, 0},
	x86.AMOVSD:     gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMOVSS:     gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},

	// We use MOVAPD as a faster synonym for MOVSD.
	x86.AMOVAPD:   gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightWrite | gc.Move, 0, 0, 0},
	x86.AMULB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.SetCarry, AX, AX, 0},
	x86.AMULL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.SetCarry, AX, AX | DX, 0},
	x86.AMULQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.SetCarry, AX, AX | DX, 0},
	x86.AMULW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.SetCarry, AX, AX | DX, 0},
	x86.AMULSD:    gc.ProgInfo{gc.SizeD | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.AMULSS:    gc.ProgInfo{gc.SizeF | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.ANEGB:     gc.ProgInfo{gc.SizeB | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ANEGL:     gc.ProgInfo{gc.SizeL | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ANEGQ:     gc.ProgInfo{gc.SizeQ | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ANEGW:     gc.ProgInfo{gc.SizeW | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ANOTB:     gc.ProgInfo{gc.SizeB | RightRdwr, 0, 0, 0},
	x86.ANOTL:     gc.ProgInfo{gc.SizeL | RightRdwr, 0, 0, 0},
	x86.ANOTQ:     gc.ProgInfo{gc.SizeQ | RightRdwr, 0, 0, 0},
	x86.ANOTW:     gc.ProgInfo{gc.SizeW | RightRdwr, 0, 0, 0},
	x86.AORB:      gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AORL:      gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AORQ:      gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AORW:      gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.APOPQ:     gc.ProgInfo{gc.SizeQ | gc.RightWrite, 0, 0, 0},
	x86.APUSHQ:    gc.ProgInfo{gc.SizeQ | gc.LeftRead, 0, 0, 0},
	x86.ARCLB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCLL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCLQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCLW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCRB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCRL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCRQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ARCRW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.AREP:      gc.ProgInfo{gc.OK, CX, CX, 0},
	x86.AREPN:     gc.ProgInfo{gc.OK, CX, CX, 0},
	obj.ARET:      gc.ProgInfo{gc.Break | gc.KillCarry, 0, 0, 0},
	x86.AROLB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.AROLL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.AROLQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.AROLW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ARORB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ARORL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ARORQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ARORW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASALB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASALL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASALQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASALW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASARB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASARL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASARQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASARW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASBBB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ASBBL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ASBBQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ASBBW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry | gc.UseCarry, 0, 0, 0},
	x86.ASHLB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHLL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHLQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHLW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHRB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHRL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHRQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASHRW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.ShiftCX | gc.SetCarry, 0, 0, 0},
	x86.ASTOSB:    gc.ProgInfo{gc.OK, AX | DI, DI, 0},
	x86.ASTOSL:    gc.ProgInfo{gc.OK, AX | DI, DI, 0},
	x86.ASTOSQ:    gc.ProgInfo{gc.OK, AX | DI, DI, 0},
	x86.ASTOSW:    gc.ProgInfo{gc.OK, AX | DI, DI, 0},
	obj.ADUFFZERO: gc.ProgInfo{gc.OK, AX | DI, DI, 0},
	x86.ASUBB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ASUBL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ASUBQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ASUBW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.ASUBSD:    gc.ProgInfo{gc.SizeD | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.ASUBSS:    gc.ProgInfo{gc.SizeF | gc.LeftRead | RightRdwr, 0, 0, 0},
	x86.ATESTB:    gc.ProgInfo{gc.SizeB | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ATESTL:    gc.ProgInfo{gc.SizeL | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ATESTQ:    gc.ProgInfo{gc.SizeQ | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.ATESTW:    gc.ProgInfo{gc.SizeW | gc.LeftRead | gc.RightRead | gc.SetCarry, 0, 0, 0},
	x86.AUCOMISD:  gc.ProgInfo{gc.SizeD | gc.LeftRead | gc.RightRead, 0, 0, 0},
	x86.AUCOMISS:  gc.ProgInfo{gc.SizeF | gc.LeftRead | gc.RightRead, 0, 0, 0},
	x86.AXCHGB:    gc.ProgInfo{gc.SizeB | LeftRdwr | RightRdwr, 0, 0, 0},
	x86.AXCHGL:    gc.ProgInfo{gc.SizeL | LeftRdwr | RightRdwr, 0, 0, 0},
	x86.AXCHGQ:    gc.ProgInfo{gc.SizeQ | LeftRdwr | RightRdwr, 0, 0, 0},
	x86.AXCHGW:    gc.ProgInfo{gc.SizeW | LeftRdwr | RightRdwr, 0, 0, 0},
	x86.AXORB:     gc.ProgInfo{gc.SizeB | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AXORL:     gc.ProgInfo{gc.SizeL | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AXORQ:     gc.ProgInfo{gc.SizeQ | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
	x86.AXORW:     gc.ProgInfo{gc.SizeW | gc.LeftRead | RightRdwr | gc.SetCarry, 0, 0, 0},
}

func proginfo(p *obj.Prog) (info gc.ProgInfo) {
	info = progtable[p.As]
	if info.Flags == 0 {
		gc.Fatal("unknown instruction %v", p)
	}

	if (info.Flags&gc.ShiftCX != 0) && p.From.Type != obj.TYPE_CONST {
		info.Reguse |= CX
	}

	if info.Flags&gc.ImulAXDX != 0 {
		if p.To.Type == obj.TYPE_NONE {
			info.Reguse |= AX
			info.Regset |= AX | DX
		} else {
			info.Flags |= RightRdwr
		}
	}

	// Addressing makes some registers used.
	if p.From.Type == obj.TYPE_MEM && p.From.Name == obj.NAME_NONE {
		info.Regindex |= RtoB(int(p.From.Reg))
	}
	if p.From.Index != x86.REG_NONE {
		info.Regindex |= RtoB(int(p.From.Index))
	}
	if p.To.Type == obj.TYPE_MEM && p.To.Name == obj.NAME_NONE {
		info.Regindex |= RtoB(int(p.To.Reg))
	}
	if p.To.Index != x86.REG_NONE {
		info.Regindex |= RtoB(int(p.To.Index))
	}

	return
}