Improved code generation

src/build/asm/Instructions.go

@@ -68,16 +68,6 @@ func (a *Assembler) Call(name string) {
 	})
 }
 
-// Jump jumps to a position that is identified by a label.
-func (a *Assembler) Jump(name string) {
-	a.Instructions = append(a.Instructions, Instruction{
-		Mnemonic: JUMP,
-		Data: &Label{
-			Name: name,
-		},
-	})
-}
-
 // Return returns back to the caller.
 func (a *Assembler) Return() {
 	if len(a.Instructions) > 0 && a.Instructions[len(a.Instructions)-1].Mnemonic == RETURN {

src/build/asm/Optimizer.go

@@ -4,10 +4,6 @@ import "git.akyoto.dev/cli/q/src/build/cpu"
 
 // unnecessary returns true if the register/register operation can be skipped.
 func (a *Assembler) unnecessary(mnemonic Mnemonic, left cpu.Register, right cpu.Register) bool {
-	if mnemonic == MOVE && left == right {
-		return true
-	}
-
 	if len(a.Instructions) == 0 {
 		return false
 	}

src/build/core/Compare.go

@@ -41,7 +41,6 @@ func (f *Function) Compare(comparison *expression.Expression) error {
 		return err
 	}
 
-	f.cpu.Use(tmp)
 	defer f.cpu.Free(tmp)
 	return f.Execute(comparison.Token, tmp, right)
 }

src/build/core/CompileCall.go

@@ -37,22 +37,18 @@ func (f *Function) CompileCall(root *expression.Expression) error {
 
 	f.SaveRegister(f.cpu.Output[0])
 
-	for _, register := range registers {
-		f.SaveRegister(register)
-	}
-
 	// Push
 	for _, register := range f.cpu.General {
 		if f.cpu.IsUsed(register) {
-			f.assembler.Register(asm.PUSH, register)
+			f.Register(asm.PUSH, register)
 		}
 	}
 
 	// Call
 	if isSyscall {
-		f.assembler.Syscall()
+		f.Syscall()
 	} else {
-		f.assembler.Call(funcName)
+		f.Call(funcName)
 	}
 
 	// Pop
@@ -60,7 +56,7 @@ func (f *Function) CompileCall(root *expression.Expression) error {
 		register := f.cpu.General[i]
 
 		if f.cpu.IsUsed(register) {
-			f.assembler.Register(asm.POP, register)
+			f.Register(asm.POP, register)
 		}
 	}
 

src/build/core/CompileCondition.go

@@ -25,7 +25,7 @@ func (f *Function) CompileCondition(condition *expression.Expression, successLab
 		f.JumpIfTrue(left.Token.Text(), successLabel)
 
 		// Right
-		f.assembler.Label(asm.LABEL, leftFailLabel)
+		f.AddLabel(leftFailLabel)
 		right := condition.Children[1]
 		err = f.CompileCondition(right, successLabel, failLabel)
 
@@ -52,7 +52,7 @@ func (f *Function) CompileCondition(condition *expression.Expression, successLab
 		f.JumpIfFalse(left.Token.Text(), failLabel)
 
 		// Right
-		f.assembler.Label(asm.LABEL, leftSuccessLabel)
+		f.AddLabel(leftSuccessLabel)
 		right := condition.Children[1]
 		err = f.CompileCondition(right, successLabel, failLabel)
 
@@ -79,17 +79,17 @@ func (f *Function) CompileCondition(condition *expression.Expression, successLab
 func (f *Function) JumpIfFalse(operator string, label string) {
 	switch operator {
 	case "==":
-		f.assembler.Label(asm.JNE, label)
+		f.Jump(asm.JNE, label)
 	case "!=":
-		f.assembler.Label(asm.JE, label)
+		f.Jump(asm.JE, label)
 	case ">":
-		f.assembler.Label(asm.JLE, label)
+		f.Jump(asm.JLE, label)
 	case "<":
-		f.assembler.Label(asm.JGE, label)
+		f.Jump(asm.JGE, label)
 	case ">=":
-		f.assembler.Label(asm.JL, label)
+		f.Jump(asm.JL, label)
 	case "<=":
-		f.assembler.Label(asm.JG, label)
+		f.Jump(asm.JG, label)
 	}
 }
 
@@ -97,16 +97,16 @@ func (f *Function) JumpIfFalse(operator string, label string) {
 func (f *Function) JumpIfTrue(operator string, label string) {
 	switch operator {
 	case "==":
-		f.assembler.Label(asm.JE, label)
+		f.Jump(asm.JE, label)
 	case "!=":
-		f.assembler.Label(asm.JNE, label)
+		f.Jump(asm.JNE, label)
 	case ">":
-		f.assembler.Label(asm.JG, label)
+		f.Jump(asm.JG, label)
 	case "<":
-		f.assembler.Label(asm.JL, label)
+		f.Jump(asm.JL, label)
 	case ">=":
-		f.assembler.Label(asm.JGE, label)
+		f.Jump(asm.JGE, label)
 	case "<=":
-		f.assembler.Label(asm.JLE, label)
+		f.Jump(asm.JLE, label)
 	}
 }

src/build/core/CompileDefinition.go

@@ -43,7 +43,7 @@ func (f *Function) CompileDefinition(node *ast.Define) error {
 
 func (f *Function) AddVariable(variable *Variable) {
 	if config.Comments {
-		f.assembler.Comment(fmt.Sprintf("%s = %s (%s, %d uses)", variable.Name, variable.Value, variable.Register, variable.Alive))
+		f.Comment(fmt.Sprintf("%s = %s (%s, %d uses)", variable.Name, variable.Value, variable.Register, variable.Alive))
 	}
 
 	f.variables[variable.Name] = variable
@@ -60,7 +60,7 @@ func (f *Function) useVariable(variable *Variable) {
 
 	if variable.Alive == 0 {
 		if config.Comments {
-			f.assembler.Comment(fmt.Sprintf("%s died (%s)", variable.Name, variable.Register))
+			f.Comment(fmt.Sprintf("%s died (%s)", variable.Name, variable.Register))
 		}
 
 		f.cpu.Free(variable.Register)

src/build/core/CompileIf.go

@@ -3,7 +3,6 @@ package core
 import (
 	"fmt"
 
-	"git.akyoto.dev/cli/q/src/build/asm"
 	"git.akyoto.dev/cli/q/src/build/ast"
 )
 
@@ -17,8 +16,8 @@ func (f *Function) CompileIf(branch *ast.If) error {
 		return err
 	}
 
-	f.assembler.Label(asm.LABEL, success)
-	defer f.assembler.Label(asm.LABEL, fail)
+	f.AddLabel(success)
+	defer f.AddLabel(fail)
 	f.count.branch++
 	return f.CompileAST(branch.Body)
 }

src/build/core/CompileLoop.go

@@ -10,8 +10,8 @@ import (
 // CompileLoop compiles a loop instruction.
 func (f *Function) CompileLoop(loop *ast.Loop) error {
 	label := fmt.Sprintf("%s_loop_%d", f.Name, f.count.loop)
-	f.assembler.Label(asm.LABEL, label)
-	defer f.assembler.Jump(label)
+	f.AddLabel(label)
+	defer f.Jump(asm.JUMP, label)
 	f.count.loop++
 	return f.CompileAST(loop.Body)
 }

src/build/core/CompileReturn.go

@@ -6,7 +6,7 @@ import (
 
 // CompileReturn compiles a return instruction.
 func (f *Function) CompileReturn(node *ast.Return) error {
-	defer f.assembler.Return()
+	defer f.Return()
 
 	if node.Value == nil {
 		return nil

src/build/core/Execute.go

@@ -24,7 +24,6 @@ func (f *Function) Execute(operation token.Token, register cpu.Register, value *
 	}
 
 	tmp := f.cpu.MustFindFree(f.cpu.General)
-	f.cpu.Use(tmp)
 	defer f.cpu.Free(tmp)
 
 	err := f.ExpressionToRegister(value, tmp)

src/build/core/ExecuteRegisterNumber.go

@@ -11,22 +11,22 @@ import (
 func (f *Function) ExecuteRegisterNumber(operation token.Token, register cpu.Register, number int) error {
 	switch operation.Text() {
 	case "+", "+=":
-		f.assembler.RegisterNumber(asm.ADD, register, number)
+		f.RegisterNumber(asm.ADD, register, number)
 
 	case "-", "-=":
-		f.assembler.RegisterNumber(asm.SUB, register, number)
+		f.RegisterNumber(asm.SUB, register, number)
 
 	case "*", "*=":
-		f.assembler.RegisterNumber(asm.MUL, register, number)
+		f.RegisterNumber(asm.MUL, register, number)
 
 	case "/", "/=":
-		f.assembler.RegisterNumber(asm.DIV, register, number)
+		f.RegisterNumber(asm.DIV, register, number)
 
 	case "==", "!=", "<", "<=", ">", ">=":
-		f.assembler.RegisterNumber(asm.COMPARE, register, number)
+		f.RegisterNumber(asm.COMPARE, register, number)
 
 	case "=":
-		f.assembler.RegisterNumber(asm.MOVE, register, number)
+		f.RegisterNumber(asm.MOVE, register, number)
 
 	default:
 		return errors.New(&errors.InvalidOperator{Operator: operation.Text()}, f.File, operation.Position)

src/build/core/ExecuteRegisterRegister.go

@@ -11,22 +11,22 @@ import (
 func (f *Function) ExecuteRegisterRegister(operation token.Token, destination cpu.Register, source cpu.Register) error {
 	switch operation.Text() {
 	case "+", "+=":
-		f.assembler.RegisterRegister(asm.ADD, destination, source)
+		f.RegisterRegister(asm.ADD, destination, source)
 
 	case "-", "-=":
-		f.assembler.RegisterRegister(asm.SUB, destination, source)
+		f.RegisterRegister(asm.SUB, destination, source)
 
 	case "*", "*=":
-		f.assembler.RegisterRegister(asm.MUL, destination, source)
+		f.RegisterRegister(asm.MUL, destination, source)
 
 	case "/", "/=":
-		f.assembler.RegisterRegister(asm.DIV, destination, source)
+		f.RegisterRegister(asm.DIV, destination, source)
 
 	case "==", "!=", "<", "<=", ">", ">=":
-		f.assembler.RegisterRegister(asm.COMPARE, destination, source)
+		f.RegisterRegister(asm.COMPARE, destination, source)
 
 	case "=":
-		f.assembler.RegisterRegister(asm.MOVE, destination, source)
+		f.RegisterRegister(asm.MOVE, destination, source)
 
 	default:
 		return errors.New(&errors.InvalidOperator{Operator: operation.Text()}, f.File, operation.Position)

src/build/core/ExpressionToRegister.go

@@ -18,7 +18,7 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 		err := f.CompileCall(node)
 
 		if register != f.cpu.Output[0] {
-			f.assembler.RegisterRegister(asm.MOVE, register, f.cpu.Output[0])
+			f.RegisterRegister(asm.MOVE, register, f.cpu.Output[0])
 		}
 
 		return err
@@ -34,8 +34,6 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 
 	if f.UsesRegister(right, register) {
 		register = f.cpu.MustFindFree(f.cpu.General)
-	} else {
-		f.SaveRegister(register)
 	}
 
 	f.cpu.Reserve(register)
@@ -45,11 +43,10 @@ func (f *Function) ExpressionToRegister(node *expression.Expression, register cp
 		return err
 	}
 
-	f.cpu.Use(register)
 	err = f.Execute(node.Token, register, right)
 
 	if register != final {
-		f.assembler.RegisterRegister(asm.MOVE, final, register)
+		f.RegisterRegister(asm.MOVE, final, register)
 		f.cpu.Free(register)
 	}
 

src/build/core/Function.go

@@ -46,9 +46,9 @@ func NewFunction(name string, file *fs.File, body token.List) *Function {
 // Compile turns a function into machine code.
 func (f *Function) Compile() {
 	defer close(f.finished)
-	f.assembler.Label(asm.LABEL, f.Name)
+	f.AddLabel(f.Name)
 	f.err = f.CompileTokens(f.Body)
-	f.assembler.Return()
+	f.Return()
 }
 
 // CompileTokens compiles a token list.

src/build/core/Instructions.go

@@ -0,0 +1,98 @@
+package core
+
+import (
+	"git.akyoto.dev/cli/q/src/build/asm"
+	"git.akyoto.dev/cli/q/src/build/config"
+	"git.akyoto.dev/cli/q/src/build/cpu"
+)
+
+func (f *Function) AddLabel(label string) {
+	f.assembler.Label(asm.LABEL, label)
+	f.postInstruction()
+}
+
+func (f *Function) Call(label string) {
+	f.assembler.Call(label)
+	f.cpu.Use(f.cpu.Output[0])
+	f.postInstruction()
+}
+
+func (f *Function) Comment(comment string) {
+	f.assembler.Comment(comment)
+	f.postInstruction()
+}
+
+func (f *Function) Jump(mnemonic asm.Mnemonic, label string) {
+	f.assembler.Label(mnemonic, label)
+	f.postInstruction()
+}
+
+func (f *Function) Register(mnemonic asm.Mnemonic, a cpu.Register) {
+	f.assembler.Register(mnemonic, a)
+
+	if mnemonic == asm.POP {
+		f.cpu.Use(a)
+	}
+
+	f.postInstruction()
+}
+
+func (f *Function) RegisterNumber(mnemonic asm.Mnemonic, a cpu.Register, b int) {
+	if f.cpu.IsUsed(a) && isDestructive(mnemonic) {
+		f.SaveRegister(a)
+	}
+
+	f.assembler.RegisterNumber(mnemonic, a, b)
+
+	if mnemonic == asm.MOVE {
+		f.cpu.Use(a)
+	}
+
+	f.postInstruction()
+}
+
+func (f *Function) RegisterRegister(mnemonic asm.Mnemonic, a cpu.Register, b cpu.Register) {
+	if mnemonic == asm.MOVE && a == b {
+		return
+	}
+
+	if f.cpu.IsUsed(a) && isDestructive(mnemonic) {
+		f.SaveRegister(a)
+	}
+
+	f.assembler.RegisterRegister(mnemonic, a, b)
+
+	if mnemonic == asm.MOVE {
+		f.cpu.Use(a)
+	}
+
+	f.postInstruction()
+}
+
+func (f *Function) Return() {
+	f.assembler.Return()
+	f.postInstruction()
+}
+
+func (f *Function) Syscall() {
+	f.assembler.Syscall()
+	f.cpu.Use(f.cpu.Output[0])
+	f.postInstruction()
+}
+
+func (f *Function) postInstruction() {
+	if !config.Assembler {
+		return
+	}
+
+	f.registerHistory = append(f.registerHistory, f.cpu.Used)
+}
+
+func isDestructive(mnemonic asm.Mnemonic) bool {
+	switch mnemonic {
+	case asm.MOVE, asm.ADD, asm.SUB, asm.MUL, asm.DIV:
+		return true
+	default:
+		return false
+	}
+}

src/build/core/SaveRegister.go

@@ -14,6 +14,12 @@ func (f *Function) SaveRegister(register cpu.Register) {
 		return
 	}
 
+	for _, general := range f.cpu.General {
+		if register == general {
+			return
+		}
+	}
+
 	var variable *Variable
 
 	for _, v := range f.variables {
@@ -29,13 +35,12 @@ func (f *Function) SaveRegister(register cpu.Register) {
 
 	newRegister := f.cpu.MustFindFree(f.cpu.General)
 	f.cpu.Reserve(newRegister)
-	f.cpu.Use(newRegister)
 
 	if config.Comments {
-		f.assembler.Comment(fmt.Sprintf("save %s to %s", register, newRegister))
+		f.Comment(fmt.Sprintf("save %s to %s", register, newRegister))
 	}
 
-	f.assembler.RegisterRegister(asm.MOVE, newRegister, register)
+	f.RegisterRegister(asm.MOVE, newRegister, register)
 	f.cpu.Free(register)
 	variable.Register = newRegister
 }

src/build/core/TokenToRegister.go

@@ -21,8 +21,8 @@ func (f *Function) TokenToRegister(t token.Token, register cpu.Register) error {
 			return errors.New(&errors.UnknownIdentifier{Name: name}, f.File, t.Position)
 		}
 
-		f.assembler.RegisterRegister(asm.MOVE, register, variable.Register)
 		f.useVariable(variable)
+		f.RegisterRegister(asm.MOVE, register, variable.Register)
 		return nil
 
 	case token.Number:
@@ -33,7 +33,7 @@ func (f *Function) TokenToRegister(t token.Token, register cpu.Register) error {
 			return err
 		}
 
-		f.assembler.RegisterNumber(asm.MOVE, register, n)
+		f.RegisterNumber(asm.MOVE, register, n)
 		return nil
 
 	case token.String:

src/build/core/state.go

@@ -1,6 +1,7 @@
 package core
 
 import (
+	"bytes"
 	"fmt"
 
 	"git.akyoto.dev/cli/q/src/build/asm"
@@ -10,13 +11,14 @@ import (
 
 // state is the data structure we embed in each function to preserve compilation state.
 type state struct {
-	err       error
-	variables map[string]*Variable
-	functions map[string]*Function
-	finished  chan struct{}
-	assembler asm.Assembler
-	cpu       cpu.CPU
-	count     counter
+	err             error
+	variables       map[string]*Variable
+	functions       map[string]*Function
+	registerHistory []uint64
+	finished        chan struct{}
+	assembler       asm.Assembler
+	cpu             cpu.CPU
+	count           counter
 }
 
 // counter stores how often a certain statement appeared so we can generate a unique label from it.
@@ -28,30 +30,42 @@ type counter struct {
 
 // PrintInstructions shows the assembly instructions.
 func (s *state) PrintInstructions() {
-	ansi.Dim.Println("╭────────────────────────────────────────────────────╮")
+	ansi.Dim.Println("╭──────────────────────────────────────────────────────────────────────────────╮")
 
-	for _, x := range s.assembler.Instructions {
+	for i, x := range s.assembler.Instructions {
 		ansi.Dim.Print("│ ")
 
 		switch x.Mnemonic {
 		case asm.LABEL:
-			ansi.Yellow.Printf("%-50s", x.Data.String()+":")
+			ansi.Yellow.Printf("%-44s", x.Data.String()+":")
 
 		case asm.COMMENT:
-			ansi.Dim.Printf("%-50s", x.Data.String())
+			ansi.Dim.Printf("%-44s", x.Data.String())
 
 		default:
 			ansi.Green.Printf("%-12s", x.Mnemonic.String())
 
 			if x.Data != nil {
-				fmt.Printf("%-38s", x.Data.String())
+				fmt.Printf("%-32s", x.Data.String())
 			} else {
-				fmt.Printf("%-38s", "")
+				fmt.Printf("%-32s", "")
 			}
 		}
 
+		registers := bytes.Buffer{}
+		used := s.registerHistory[i]
+
+		for _, reg := range s.cpu.All {
+			if used&(1<<reg) != 0 {
+				registers.WriteString("⬤ ")
+			} else {
+				registers.WriteString("◯ ")
+			}
+		}
+
+		ansi.Dim.Print(registers.String())
 		ansi.Dim.Print(" │\n")
 	}
 
-	ansi.Dim.Println("╰────────────────────────────────────────────────────╯")
+	ansi.Dim.Println("╰──────────────────────────────────────────────────────────────────────────────╯")
 }

src/build/cpu/CPU.go

@@ -7,34 +7,34 @@ type CPU struct {
 	Syscall  []Register
 	Input    []Register
 	Output   []Register
-	reserved uint64
-	used     uint64
+	Reserved uint64
+	Used     uint64
 }
 
 // Free will reset the reserved and used status which means the register can be allocated again.
 func (c *CPU) Free(reg Register) {
-	c.used &= ^(1 << reg)
-	c.reserved &= ^(1 << reg)
+	c.Used &= ^(1 << reg)
+	c.Reserved &= ^(1 << reg)
 }
 
 // IsReserved returns true if the register was marked for future use.
 func (c *CPU) IsReserved(reg Register) bool {
-	return c.reserved&(1<<reg) != 0
+	return c.Reserved&(1<<reg) != 0
 }
 
 // IsUsed returns true if the register is currently in use and holds a value.
 func (c *CPU) IsUsed(reg Register) bool {
-	return c.used&(1<<reg) != 0
+	return c.Used&(1<<reg) != 0
 }
 
 // Reserve reserves a register for future use.
 func (c *CPU) Reserve(reg Register) {
-	c.reserved |= (1 << reg)
+	c.Reserved |= (1 << reg)
 }
 
 // Use marks a register to be currently in use which means it must be preserved across function calls.
 func (c *CPU) Use(reg Register) {
-	c.used |= (1 << reg)
+	c.Used |= (1 << reg)
 }
 
 // FindFree tries to find a free register in the given slice of registers.

tests/programs/param-multi.q

@@ -0,0 +1,12 @@
+main() {
+	syscall(60, f(1, 2, 3))
+}
+
+f(x, y, z) {
+	w := g(4, 5, 6)
+	return x + y + z + w
+}
+
+g(x, y, z) {
+	return x + y + z
+}

tests/programs_test.go

@@ -21,14 +21,15 @@ var programs = []struct {
 	{"square-sum", "", 25},
 	{"chained-calls", "", 9},
 	{"nested-calls", "", 4},
-	{"overwrite", "", 3},
+	{"param", "", 3},
+	{"param-multi", "", 21},
 	{"reuse", "", 3},
 	{"return", "", 6},
 	{"reassign", "", 2},
 	{"branch", "", 0},
 	{"branch-and", "", 0},
 	{"branch-or", "", 0},
-	{"branch-combined", "", 0},
+	{"branch-both", "", 0},
 }
 
 func TestPrograms(t *testing.T) {
@@ -42,7 +43,7 @@ func TestPrograms(t *testing.T) {
 func BenchmarkPrograms(b *testing.B) {
 	for _, test := range programs {
 		b.Run(test.Name, func(b *testing.B) {
-			compiler := build.New(filepath.Join("programs", test.Name))
+			compiler := build.New(filepath.Join("programs", test.Name+".q"))
 
 			for i := 0; i < b.N; i++ {
 				_, err := compiler.Run()