Implemented return values

src/build/Execute.go

@@ -3,7 +3,6 @@ package build
 import (
 	"strconv"
 
-	"git.akyoto.dev/cli/q/src/build/arch/x64"
 	"git.akyoto.dev/cli/q/src/build/asm"
 	"git.akyoto.dev/cli/q/src/build/cpu"
 	"git.akyoto.dev/cli/q/src/build/expression"
@@ -17,10 +16,17 @@ func (f *Function) Execute(operation token.Token, register cpu.Register, value *
 		return f.ExecuteLeaf(operation, register, value.Token)
 	}
 
-	temporary, found := f.cpu.FindFree(f.cpu.General)
+	var temporary cpu.Register
 
-	if !found {
-		panic("no free registers")
+	if isFunctionCall(value) {
+		temporary = f.cpu.Return[0]
+	} else {
+		found := false
+		temporary, found = f.cpu.FindFree(f.cpu.General)
+
+		if !found {
+			panic("no free registers")
+		}
 	}
 
 	f.cpu.Use(temporary)
@@ -122,6 +128,20 @@ func (f *Function) ExpressionToRegister(root *expression.Expression, register cp
 		return f.TokenToRegister(operation, register)
 	}
 
+	if isFunctionCall(root) {
+		err := f.CompileFunctionCall(root)
+
+		if err != nil {
+			return err
+		}
+
+		if register != f.cpu.Return[0] {
+			f.assembler.RegisterRegister(asm.MOVE, register, f.cpu.Return[0])
+		}
+
+		return nil
+	}
+
 	left := root.Children[0]
 	right := root.Children[1]
 
@@ -131,46 +151,21 @@ func (f *Function) ExpressionToRegister(root *expression.Expression, register cp
 		return err
 	}
 
+	f.SaveRegister(register)
 	return f.Execute(operation, register, right)
 }
 
 // ExpressionsToRegisters moves multiple expressions into the specified registers.
 func (f *Function) ExpressionsToRegisters(expressions []*expression.Expression, registers []cpu.Register) error {
-	var destinations []cpu.Register
-
 	for i := len(expressions) - 1; i >= 0; i-- {
-		original := registers[i]
 		expression := expressions[i]
-
-		if expression.IsLeaf() {
-			variable, exists := f.variables[expression.Token.Text()]
-
-			if exists && variable.Register == original {
-				continue
-			}
-		}
-
-		register := original
-		save := !f.cpu.IsFree(register)
-
-		if save {
-			register = x64.RAX
-		}
+		register := registers[i]
 
 		err := f.ExpressionToRegister(expression, register)
 
 		if err != nil {
 			return err
 		}
-
-		if save {
-			destinations = append(destinations, original)
-			f.assembler.Register(asm.PUSH, x64.RAX)
-		}
-	}
-
-	for i := len(destinations) - 1; i >= 0; i-- {
-		f.assembler.Register(asm.POP, destinations[i])
 	}
 
 	return nil