q/src/core/ExpressionToRegister.go

150 lines
3.5 KiB
Go

package core
import (
"math"
"git.akyoto.dev/cli/q/src/asm"
"git.akyoto.dev/cli/q/src/ast"
"git.akyoto.dev/cli/q/src/cpu"
"git.akyoto.dev/cli/q/src/errors"
"git.akyoto.dev/cli/q/src/expression"
"git.akyoto.dev/cli/q/src/token"
"git.akyoto.dev/cli/q/src/types"
)
// ExpressionToRegister puts the result of an expression into the specified register.
func (f *Function) ExpressionToRegister(node *expression.Expression, register cpu.Register) (types.Type, error) {
if node.IsFolded {
f.RegisterNumber(asm.MOVE, register, node.Value)
return types.Int, nil
}
if node.IsLeaf() {
return f.TokenToRegister(node.Token, register)
}
if ast.IsFunctionCall(node) {
types, err := f.CompileCall(node)
if err != nil {
return nil, err
}
if register != f.CPU.Output[0] {
f.RegisterRegister(asm.MOVE, register, f.CPU.Output[0])
}
if len(types) == 0 {
return nil, nil
}
return types[0], err
}
if node.Token.Kind == token.Array {
name := node.Children[0].Token.Text(f.File.Bytes)
array := f.VariableByName(name)
if array == nil {
return nil, errors.New(&errors.UnknownIdentifier{Name: name}, f.File, node.Children[0].Token.Position)
}
index := node.Children[1]
memory := asm.Memory{
Base: array.Register,
Offset: 0,
OffsetRegister: cpu.Register(math.MaxUint8),
Length: byte(1),
}
if index.Token.IsNumeric() {
offset, err := f.ToNumber(index.Token)
if err != nil {
return nil, err
}
memory.Offset = int8(offset)
} else {
typ, err := f.ExpressionToRegister(index, register)
if err != nil {
return nil, err
}
if !types.Is(typ, types.Int) {
return nil, errors.New(&errors.TypeMismatch{Encountered: typ.Name(), Expected: types.Int.Name()}, f.File, index.Token.Position)
}
memory.OffsetRegister = register
}
f.MemoryRegister(asm.LOAD, memory, register)
return types.Int, nil
}
if node.Token.Kind == token.Period {
left := node.Children[0]
leftText := left.Token.Text(f.File.Bytes)
right := node.Children[1]
rightText := right.Token.Text(f.File.Bytes)
variable := f.VariableByName(leftText)
if variable == nil {
constant, isConst := f.Constants[f.Package+"."+leftText+"."+rightText]
if isConst {
return f.TokenToRegister(constant.Value, register)
}
return nil, errors.New(&errors.UnknownIdentifier{Name: leftText}, f.File, left.Token.Position)
}
field := variable.Type.(*types.Pointer).To.(*types.Struct).FieldByName(rightText)
f.MemoryRegister(asm.LOAD, asm.Memory{Base: variable.Register, Offset: int8(field.Offset), Length: byte(field.Type.Size())}, register)
return field.Type, nil
}
if len(node.Children) == 1 {
if !node.Token.IsUnaryOperator() {
return nil, errors.New(errors.MissingOperand, f.File, node.Token.End())
}
typ, err := f.ExpressionToRegister(node.Children[0], register)
if err != nil {
return typ, err
}
return typ, f.ExecuteRegister(node.Token, register)
}
left := node.Children[0]
right := node.Children[1]
final := register
if f.UsesRegister(right, register) {
register = f.NewRegister()
}
typ, err := f.ExpressionToRegister(left, register)
if err != nil {
return nil, err
}
if typ == types.AnyPointer && right.Token.Kind == token.Identifier && f.VariableByName(right.Token.Text(f.File.Bytes)).Type == types.AnyPointer {
typ = types.Int
}
err = f.Execute(node.Token, register, right)
if register != final {
f.RegisterRegister(asm.MOVE, final, register)
f.FreeRegister(register)
}
return typ, err
}