1 files changed, 41 insertions, 4 deletions

diff --git a/src/ir.c b/src/ir.c
index f1b7eb9..86a1a9a 100644
--- a/src/ir.c
+++ b/src/ir.c
@@ -13,8 +13,8 @@ emit_arith(ProgramBASM *program, Node *node,  Operator op) {
     Operand reg_b;
     for (size_t i = 1; i < array_size(node->builtin.args); ++i) {
         Node *arg = node->builtin.args[i];
-        Operand reg_dst = NEW_REG();
         reg_b = emit_basm(program, arg);
+        Operand reg_dst = NEW_REG();
         EMIT_2(program, line, op, reg_dst, reg_a, reg_b);
         reg_a = reg_dst;
     }
@@ -90,14 +90,50 @@ emit_bool(ProgramBASM *program, Node *node) {
     return reg_dst;
 }
 
-// TODO: emit_if
+Operand
+emit_if(ProgramBASM *program, Node *node) {
+    LineInfo line = (LineInfo){.line = node->line, .col = node->col};
+    Operand label_false = NEW_LAB();
+    Operand label_end = NEW_LAB();
+
+    // If type of expression is `void`, there is nothing to return. Don't
+    // generate a new register or copy output.
+    Operand reg_out = (Operand){0};
+    if (node->expr_type != &default_types[TYPE_VOID]) {
+        reg_out = NEW_REG();
+    }
+
+    Operand cond = emit_basm(program, node->ifexpr.cond);
+    EMIT_1(program, line, OP_JMP_FALSE, label_false, cond);
+
+    Operand ret_true = emit_basm(program, node->ifexpr.expr_true);
+    if (node->ifexpr.expr_false != NULL) {
+        if (node->expr_type != &default_types[TYPE_VOID]) {
+            EMIT_1(program, line, OP_CP64, reg_out, ret_true); // TODO: depends on the type of output
+        }
+        EMIT_0(program, line, OP_JMP, label_end);
+        EMIT_0(program, line, OP_LABEL, label_false);
+        Operand ret_false = emit_basm(program, node->ifexpr.expr_false);
+        if (node->expr_type != &default_types[TYPE_VOID]) {
+            EMIT_1(program, line, OP_CP64, reg_out, ret_false); // TODO: depends on the type of output
+        }
+        EMIT_0(program, line, OP_LABEL, label_end);
+    } else {
+        EMIT_0(program, line, OP_LABEL, label_false);
+    }
+
+    return reg_out;
+}
+
 // TODO: emit_and
 // TODO: emit_or
 // TODO: emit_not
-// TODO: emit_global
-// TODO: emit_local
+// TODO: emit_block
 // TODO: emit_procedure
+// TODO: emit_local_vars
+// TODO: emit_param_vars
 // TODO: emit_proc_call
+// TODO: emit_global_vars
 
 Operand
 emit_basm(ProgramBASM *program, Node *node) {
@@ -105,6 +141,7 @@ emit_basm(ProgramBASM *program, Node *node) {
         case NODE_BOOL: { return emit_bool(program, node); } break;
         case NODE_NUMBER: { return emit_number(program, node); } break;
         case NODE_BUILTIN: { return emit_builtin(program, node); } break;
+        case NODE_IF: { return emit_if(program, node); } break;
         default: {
             push_error(ERR_TYPE_BASM, ERR_UNIMPLEMENTED, node->line, node->col);
             return (Operand){0};