avo/operand/checks.go

package operand

import (
	"math"

	"github.com/mmcloughlin/avo/reg"

	"github.com/mmcloughlin/avo"
)

// Is1 returns true if op is the immediate constant 1.
func Is1(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i == 1
}

// Is3 returns true if op is the immediate constant 3.
func Is3(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i == 3
}

// IsImm2u returns true if op is a 2-bit unsigned immediate (less than 4).
func IsImm2u(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i < 4
}

// IsImm8 returns true is op is an 8-bit immediate.
func IsImm8(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i <= math.MaxUint8
}

// IsImm16 returns true is op is a 16-bit immediate.
func IsImm16(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i <= math.MaxUint16
}

// IsImm32 returns true is op is a 32-bit immediate.
func IsImm32(op avo.Operand) bool {
	i, ok := op.(Imm)
	return ok && i <= math.MaxUint32
}

// IsImm64 returns true is op is a 64-bit immediate.
func IsImm64(op avo.Operand) bool {
	_, ok := op.(Imm)
	return ok
}

// IsAl returns true if op is the AL register.
func IsAl(op avo.Operand) bool {
	return op == reg.AL
}

// IsCl returns true if op is the CL register.
func IsCl(op avo.Operand) bool {
	return op == reg.CL
}

// IsAx returns true if op is the 16-bit AX register.
func IsAx(op avo.Operand) bool {
	return op == reg.AX
}

// IsEax returns true if op is the 32-bit EAX register.
func IsEax(op avo.Operand) bool {
	return op == reg.EAX
}

// IsRax returns true if op is the 64-bit RAX register.
func IsRax(op avo.Operand) bool {
	return op == reg.RAX
}

// IsR8 returns true if op is an 8-bit general-purpose register.
func IsR8(op avo.Operand) bool {
	return IsGP(op, 1)
}

// IsR16 returns true if op is a 16-bit general-purpose register.
func IsR16(op avo.Operand) bool {
	return IsGP(op, 2)
}

// IsR32 returns true if op is a 32-bit general-purpose register.
func IsR32(op avo.Operand) bool {
	return IsGP(op, 4)
}

// IsR64 returns true if op is a 64-bit general-purpose register.
func IsR64(op avo.Operand) bool {
	return IsGP(op, 8)
}

// IsGP returns true if op is a general-purpose register of size n bytes.
func IsGP(op avo.Operand, n uint) bool {
	return IsRegisterKindSize(op, reg.GP, n)
}

// IsXmm0 returns true if op is the X0 register.
func IsXmm0(op avo.Operand) bool {
	return op == reg.X0
}

// IsXmm returns true if op is a 128-bit XMM register.
func IsXmm(op avo.Operand) bool {
	return IsRegisterKindSize(op, reg.SSEAVX, 16)
}

// IsYmm returns true if op is a 256-bit YMM register.
func IsYmm(op avo.Operand) bool {
	return IsRegisterKindSize(op, reg.SSEAVX, 32)
}

// IsRegisterKindSize returns true if op is a register of the given kind and size in bytes.
func IsRegisterKindSize(op avo.Operand, k reg.Kind, n uint) bool {
	r, ok := op.(reg.Register)
	return ok && r.Kind() == k && r.Bytes() == n
}

// IsM returns true if op is a 16-, 32- or 64-bit memory operand.
func IsM(op avo.Operand) bool {
	// TODO(mbm): confirm "m" check is defined correctly
	// Intel manual: "A 16-, 32- or 64-bit operand in memory."
	return IsM16(op) || IsM32(op) || IsM64(op)
}

// IsM8 returns true if op is an 8-bit memory operand.
func IsM8(op avo.Operand) bool {
	// TODO(mbm): confirm "m8" check is defined correctly
	// Intel manual: "A byte operand in memory, usually expressed as a variable or
	// array name, but pointed to by the DS:(E)SI or ES:(E)DI registers. In 64-bit
	// mode, it is pointed to by the RSI or RDI registers."
	return IsMSize(op, 1)
}

// IsM16 returns true if op is a 16-bit memory operand.
func IsM16(op avo.Operand) bool {
	return IsMSize(op, 2)
}

// IsM32 returns true if op is a 16-bit memory operand.
func IsM32(op avo.Operand) bool {
	return IsMSize(op, 4)
}

// IsM64 returns true if op is a 64-bit memory operand.
func IsM64(op avo.Operand) bool {
	return IsMSize(op, 8)
}

// IsMSize returns true if op is a memory operand using general-purpose address
// registers of the given size in bytes.
func IsMSize(op avo.Operand, n uint) bool {
	// TODO(mbm): should memory operands have a size attribute as well?
	m, ok := op.(Mem)
	return ok && IsGP(m.Base, n) && (m.Index == nil || IsGP(m.Index, n))
}

// IsM128 returns true if op is a 128-bit memory operand.
func IsM128(op avo.Operand) bool {
	// TODO(mbm): should "m128" be the same as "m64"?
	return IsM64(op)
}

// IsM256 returns true if op is a 256-bit memory operand.
func IsM256(op avo.Operand) bool {
	// TODO(mbm): should "m256" be the same as "m64"?
	return IsM64(op)
}

func IsVm32x(op avo.Operand) bool {
	return false
}

func IsVm64x(op avo.Operand) bool {
	return false
}

func IsVm32y(op avo.Operand) bool {
	return false
}

func IsVm64y(op avo.Operand) bool {
	return false
}

func IsRel8(op avo.Operand) bool {
	return false
}

func IsRel32(op avo.Operand) bool {
	return false
}