q/src/core/CompileFor.go
2025-02-27 14:16:25 +01:00

96 lines
2 KiB
Go

package core
import (
"git.urbach.dev/cli/q/src/asm"
"git.urbach.dev/cli/q/src/ast"
"git.urbach.dev/cli/q/src/cpu"
"git.urbach.dev/cli/q/src/errors"
"git.urbach.dev/cli/q/src/expression"
"git.urbach.dev/cli/q/src/token"
"git.urbach.dev/cli/q/src/types"
)
// CompileFor compiles a for loop.
func (f *Function) CompileFor(loop *ast.For) error {
for _, register := range f.CPU.Input {
f.SaveRegister(register)
}
f.count.loop++
var (
label = f.CreateLabel("for", f.count.loop)
labelEnd = f.CreateLabel("for end", f.count.loop)
counter cpu.Register
from *expression.Expression
to *expression.Expression
)
scope := f.PushScope(loop.Body, f.File.Bytes)
scope.InLoop = true
switch loop.Head.Token.Kind {
case token.Define:
variable, err := f.Define(loop.Head.Children[0])
if err != nil {
return err
}
counter = variable.Register
from = loop.Head.Children[1].Children[0]
to = loop.Head.Children[1].Children[1]
f.AddVariable(variable)
case token.Range:
counter = f.NewRegister()
defer f.FreeRegister(counter)
from = loop.Head.Children[0]
to = loop.Head.Children[1]
default:
panic("could not recognize loop header")
}
_, err := f.ExpressionToRegister(from, counter)
if err != nil {
return err
}
if to.Token.IsNumeric() {
number, err := f.ToNumber(to.Token)
if err != nil {
return err
}
f.AddLabel(label)
f.RegisterNumber(asm.COMPARE, counter, number)
} else {
value, isTemporary, err := f.Evaluate(to)
if err != nil {
return err
}
if !types.Is(value.Type, types.AnyInt) {
return errors.New(&errors.TypeMismatch{Encountered: value.Type.Name(), Expected: types.AnyInt.Name()}, f.File, to.Token.Position)
}
if isTemporary {
defer f.FreeRegister(value.Register)
}
f.AddLabel(label)
f.RegisterRegister(asm.COMPARE, counter, value.Register)
}
f.Jump(asm.JGE, labelEnd)
err = f.CompileAST(loop.Body)
f.RegisterNumber(asm.ADD, counter, 1)
f.Jump(asm.JUMP, label)
f.AddLabel(labelEnd)
f.PopScope()
return err
}