Initial commit

1 files changed, 85 insertions, 0 deletions

diff --git a/generate.go b/generate.go
new file mode 100644
index 0000000..75da82e
--- /dev/null
+++ b/generate.go
@@ -0,0 +1,85 @@
+package main
+
+import (
+	"fmt"
+	"io"
+)
+
+type invalidToplevel struct {
+	got expression
+}
+
+func (i invalidToplevel) Error() string {
+	return fmt.Sprintf("%d: expected top-level declaration, got %s", i.got.line(), i.got)
+}
+
+func generate(root *rootExpr, w io.Writer, errs chan<- error) {
+	defer wg.Done()
+
+	for _, toplevel := range root.toplevels {
+		if err := generateToplevel(toplevel, w); err != nil {
+			errs <- err
+		}
+	}
+}
+
+func generateToplevel(toplevel expression, w io.Writer) error {
+	switch expr := toplevel.(type) {
+	case *functionExpr:
+		return generateFunction(expr, w)
+	}
+
+	return invalidToplevel{got: toplevel}
+}
+
+func generateFunction(function *functionExpr, w io.Writer) error {
+	if function.link != defaultLinkage {
+		fmt.Fprintf(w, "%s ", function.link)
+	}
+
+	fmt.Fprintf(w, "function %s $%s", function.returnType, function.name)
+	fmt.Fprintf(w, "(%s) {\n", function.params)
+	fmt.Fprintln(w, "@start")
+	if err := generateBlock(function.blk, w); err != nil {
+		return err
+	}
+	fmt.Fprintf(w, "}\n")
+
+	return nil
+}
+
+func generateBlock(blk *blockExpr, w io.Writer) error {
+	for _, stmt := range blk.stmts {
+		if err := generateStatement(stmt, w); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func generateStatement(stmt statementExpr, w io.Writer) error {
+	switch s := stmt.(type) {
+	case *returnStmt:
+		return generateReturnStmt(s, w)
+	}
+
+	return nil
+}
+
+func generateReturnStmt(stmt *returnStmt, w io.Writer) error {
+	eq := stmt.value.(*equalityExpr)
+	cmp := eq.lhs
+	trm := cmp.lhs
+	num := trm.lhs
+	fct := num.lhs
+	un := fct.lhs
+	prm := un.value
+	lit := prm.(literalExpr)
+	n := lit.(*numberExpr)
+	value := n.s
+
+	fmt.Fprintln(w, "ret", value)
+
+	return nil
+}