implement expression handling further

+ Add some notes about returning functions that I started thinking about
  as a result of the fib example

1 files changed, 30 insertions, 0 deletions

diff --git a/src/lower.c b/src/lower.c
index ad3d1b9..46ce2c3 100644
--- a/src/lower.c
+++ b/src/lower.c
@@ -44,6 +44,13 @@ static int lower_binop(struct state *state, struct ast *binop)
 		return -1;
 
 	switch (binop->k) {
+	case AST_ADD:	printf(" + "); break;
+	case AST_SUB:	printf(" - "); break;
+	case AST_MUL:	printf(" * "); break;
+	case AST_DIV:	printf(" / "); break;
+	case AST_REM:	printf(" %% "); break;
+	case AST_LSHIFT:	printf(" << "); break;
+	case AST_RSHIFT:	printf(" >> "); break;
 	default:
 		internal_error("missing binop lowering");
 		return -1;
@@ -63,6 +70,12 @@ static int lower_comparison(struct state *state, struct ast *comp)
 		return -1;
 
 	switch (comp->k) {
+	case AST_LT: printf(" < "); break;
+	case AST_GT: printf(" > "); break;
+	case AST_LE: printf(" <= "); break;
+	case AST_GE: printf(" <= "); break;
+	case AST_NE: printf(" != "); break;
+	case AST_EQ: printf(" == "); break;
 	default:
 		internal_error("missing comparison lowering");
 		return -1;
@@ -148,8 +161,25 @@ static int lower_init(struct state *state, struct ast *init)
 	return 0;
 }
 
+static int lower_unop(struct state *state, struct ast *expr)
+{
+	switch (expr->k) {
+	case AST_LNOT:	printf("-"); break;
+	case AST_NOT:	printf("~"); break;
+	case AST_NEG:	printf("-"); break;
+	default:
+		internal_error("missing unop lowering");
+		return -1;
+	}
+
+	return lower_expr(state, unop_expr(expr));
+}
+
 static int lower_expr(struct state *state, struct ast *expr)
 {
+	if (is_unop(expr))
+		return lower_unop(state, expr);
+
 	if (is_binop(expr))
 		return lower_binop(state, expr);