q/src/asm/Finalize.go
2025-02-05 23:16:18 +01:00

361 lines
9.7 KiB
Go

package asm
import (
"math"
"strings"
"git.akyoto.dev/cli/q/src/config"
"git.akyoto.dev/cli/q/src/dll"
"git.akyoto.dev/cli/q/src/x86"
)
// Finalize generates the final machine code.
func (a Assembler) Finalize(dlls dll.List) ([]byte, []byte) {
var (
code = make([]byte, 0, len(a.Instructions)*8)
data []byte
codeLabels = map[string]Address{}
dataLabels map[string]Address
codePointers []*pointer
dataPointers []*pointer
dllPointers []*pointer
codeStart = CodeOffset()
)
for _, x := range a.Instructions {
switch x.Mnemonic {
case ADD:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.AddRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.AddRegisterRegister(code, operands.Destination, operands.Source)
}
case AND:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.AndRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.AndRegisterRegister(code, operands.Destination, operands.Source)
}
case SUB:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.SubRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.SubRegisterRegister(code, operands.Destination, operands.Source)
}
case MUL:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.MulRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.MulRegisterRegister(code, operands.Destination, operands.Source)
}
case DIV:
switch operands := x.Data.(type) {
case *RegisterRegister:
if operands.Destination != x86.RAX {
code = x86.MoveRegisterRegister(code, x86.RAX, operands.Destination)
}
code = x86.ExtendRAXToRDX(code)
code = x86.DivRegister(code, operands.Source)
if operands.Destination != x86.RAX {
code = x86.MoveRegisterRegister(code, operands.Destination, x86.RAX)
}
}
case MODULO:
switch operands := x.Data.(type) {
case *RegisterRegister:
if operands.Destination != x86.RAX {
code = x86.MoveRegisterRegister(code, x86.RAX, operands.Destination)
}
code = x86.ExtendRAXToRDX(code)
code = x86.DivRegister(code, operands.Source)
if operands.Destination != x86.RDX {
code = x86.MoveRegisterRegister(code, operands.Destination, x86.RDX)
}
}
case CALL:
code = x86.Call(code, 0x00_00_00_00)
size := 4
label := x.Data.(*Label)
pointer := &pointer{
Position: Address(len(code) - size),
OpSize: 1,
Size: uint8(size),
}
pointer.Resolve = func() Address {
destination, exists := codeLabels[label.Name]
if !exists {
panic("unknown jump label")
}
distance := destination - (pointer.Position + Address(pointer.Size))
return Address(distance)
}
codePointers = append(codePointers, pointer)
case COMMENT:
continue
case COMPARE:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.CompareRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.CompareRegisterRegister(code, operands.Destination, operands.Source)
}
case DLLCALL:
size := 4
// TODO: R15 could be in use.
code = x86.MoveRegisterRegister(code, x86.R15, x86.RSP)
code = x86.AlignStack(code)
code = x86.SubRegisterNumber(code, x86.RSP, 32)
code = x86.CallAtAddress(code, 0x00_00_00_00)
position := len(code) - size
code = x86.MoveRegisterRegister(code, x86.RSP, x86.R15)
label := x.Data.(*Label)
pointer := &pointer{
Position: Address(position),
OpSize: 2,
Size: uint8(size),
}
pointer.Resolve = func() Address {
dot := strings.Index(label.Name, ".")
library := label.Name[:dot]
funcName := label.Name[dot+1:]
index := dlls.Index(library, funcName)
if index == -1 {
panic("unknown DLL function " + label.Name)
}
return Address(index * 8)
}
dllPointers = append(dllPointers, pointer)
case JE, JNE, JG, JGE, JL, JLE, JUMP:
switch x.Mnemonic {
case JE:
code = x86.Jump8IfEqual(code, 0x00)
case JNE:
code = x86.Jump8IfNotEqual(code, 0x00)
case JG:
code = x86.Jump8IfGreater(code, 0x00)
case JGE:
code = x86.Jump8IfGreaterOrEqual(code, 0x00)
case JL:
code = x86.Jump8IfLess(code, 0x00)
case JLE:
code = x86.Jump8IfLessOrEqual(code, 0x00)
case JUMP:
code = x86.Jump8(code, 0x00)
}
size := 1
label := x.Data.(*Label)
pointer := &pointer{
Position: Address(len(code) - size),
OpSize: 1,
Size: uint8(size),
}
pointer.Resolve = func() Address {
destination, exists := codeLabels[label.Name]
if !exists {
panic("unknown jump label")
}
distance := destination - (pointer.Position + Address(pointer.Size))
return Address(distance)
}
codePointers = append(codePointers, pointer)
case LABEL:
codeLabels[x.Data.(*Label).Name] = Address(len(code))
case LOAD:
switch operands := x.Data.(type) {
case *MemoryRegister:
code = x86.LoadRegister(code, operands.Register, operands.Address.Offset, operands.Address.Length, operands.Address.Base)
}
case MOVE:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.MoveRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.MoveRegisterRegister(code, operands.Destination, operands.Source)
case *RegisterLabel:
start := len(code)
code = x86.MoveRegisterNumber(code, operands.Register, 0x00_00_00_00)
size := 4
opSize := len(code) - size - start
regLabel := x.Data.(*RegisterLabel)
if strings.HasPrefix(regLabel.Label, "data_") {
dataPointers = append(dataPointers, &pointer{
Position: Address(len(code) - size),
OpSize: uint8(opSize),
Size: uint8(size),
Resolve: func() Address {
destination, exists := dataLabels[regLabel.Label]
if !exists {
panic("unknown label")
}
return Address(destination)
},
})
} else {
codePointers = append(codePointers, &pointer{
Position: Address(len(code) - size),
OpSize: uint8(opSize),
Size: uint8(size),
Resolve: func() Address {
destination, exists := codeLabels[regLabel.Label]
if !exists {
panic("unknown label")
}
return config.BaseAddress + codeStart + destination
},
})
}
}
case NEGATE:
switch operands := x.Data.(type) {
case *Register:
code = x86.NegateRegister(code, operands.Register)
}
case OR:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.OrRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.OrRegisterRegister(code, operands.Destination, operands.Source)
}
case POP:
switch operands := x.Data.(type) {
case *Register:
code = x86.PopRegister(code, operands.Register)
}
case PUSH:
switch operands := x.Data.(type) {
case *Register:
code = x86.PushRegister(code, operands.Register)
}
case RETURN:
code = x86.Return(code)
case SHIFTL:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.ShiftLeftNumber(code, operands.Register, byte(operands.Number)&0b111111)
}
case SHIFTRS:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.ShiftRightSignedNumber(code, operands.Register, byte(operands.Number)&0b111111)
}
case STORE:
switch operands := x.Data.(type) {
case *MemoryNumber:
if operands.Address.OffsetRegister == math.MaxUint8 {
code = x86.StoreNumber(code, operands.Address.Base, operands.Address.Offset, operands.Address.Length, operands.Number)
} else {
code = x86.StoreDynamicNumber(code, operands.Address.Base, operands.Address.OffsetRegister, operands.Address.Length, operands.Number)
}
case *MemoryLabel:
start := len(code)
if operands.Address.OffsetRegister == math.MaxUint8 {
code = x86.StoreNumber(code, operands.Address.Base, operands.Address.Offset, operands.Address.Length, 0b00_00_00_00)
} else {
code = x86.StoreDynamicNumber(code, operands.Address.Base, operands.Address.OffsetRegister, operands.Address.Length, 0b00_00_00_00)
}
size := 4
opSize := len(code) - size - start
memLabel := x.Data.(*MemoryLabel)
codePointers = append(codePointers, &pointer{
Position: Address(len(code) - size),
OpSize: uint8(opSize),
Size: uint8(size),
Resolve: func() Address {
destination, exists := codeLabels[memLabel.Label]
if !exists {
panic("unknown label")
}
return config.BaseAddress + codeStart + destination
},
})
case *MemoryRegister:
if operands.Address.OffsetRegister == math.MaxUint8 {
code = x86.StoreRegister(code, operands.Address.Base, operands.Address.Offset, operands.Address.Length, operands.Register)
} else {
code = x86.StoreDynamicRegister(code, operands.Address.Base, operands.Address.OffsetRegister, operands.Address.Length, operands.Register)
}
}
case SYSCALL:
code = x86.Syscall(code)
case XOR:
switch operands := x.Data.(type) {
case *RegisterNumber:
code = x86.XorRegisterNumber(code, operands.Register, operands.Number)
case *RegisterRegister:
code = x86.XorRegisterRegister(code, operands.Destination, operands.Source)
}
default:
panic("unknown mnemonic: " + x.Mnemonic.String())
}
}
data, dataLabels = a.Data.Finalize()
if config.TargetOS == config.Windows && len(data) == 0 {
data = []byte{0}
}
code = a.resolvePointers(code, data, codeStart, codeLabels, codePointers, dataPointers, dllPointers)
return code, data
}