Improved code generation

src/build/core/CompileCall.go

@@ -1,7 +1,7 @@
 package core
 
 import (
-	"git.akyoto.dev/cli/q/src/build/cpu"
+	"git.akyoto.dev/cli/q/src/build/asm"
 	"git.akyoto.dev/cli/q/src/build/expression"
 )
 
@@ -9,9 +9,43 @@ import (
 // All call registers must hold the correct parameter values before the function invocation.
 // Registers that are in use must be saved if they are modified by the function.
 // After the function call, they must be restored in reverse order.
-func (f *Function) CompileCall(expr *expression.Expression) error {
-	_, err := f.EvaluateCall(expr)
-	return err
+func (f *Function) CompileCall(root *expression.Expression) error {
+	funcName := root.Children[0].Token.Text()
+	parameters := root.Children[1:]
+	registers := f.cpu.Input[:len(parameters)]
+	isSyscall := funcName == "syscall"
+
+	if isSyscall {
+		registers = f.cpu.Syscall[:len(parameters)]
+	}
+
+	err := f.ExpressionsToRegisters(parameters, registers)
+
+	if err != nil {
+		return err
+	}
+
+	for _, register := range f.cpu.General {
+		if !f.cpu.IsFree(register) {
+			f.assembler.Register(asm.PUSH, register)
+		}
+	}
+
+	if isSyscall {
+		f.assembler.Syscall()
+	} else {
+		f.assembler.Call(funcName)
+	}
+
+	for i := len(f.cpu.General) - 1; i >= 0; i-- {
+		register := f.cpu.General[i]
+
+		if !f.cpu.IsFree(register) {
+			f.assembler.Register(asm.POP, register)
+		}
+	}
+
+	return nil
 }
 
 // CompileSyscall executes a syscall.
@@ -23,17 +57,3 @@ func (f *Function) CompileSyscall(expr *expression.Expression) error {
 	f.sideEffects++
 	return err
 }
-
-// ExpressionsToRegisters moves multiple expressions into the specified registers.
-func (f *Function) ExpressionsToRegisters(expressions []*expression.Expression, registers []cpu.Register) error {
-	for i := len(registers) - 1; i >= 0; i-- {
-		f.SaveRegister(registers[i])
-		err := f.EvaluateTo(expressions[i], registers[i])
-
-		if err != nil {
-			return err
-		}
-	}
-
-	return nil
-}