1 files changed, 51 insertions, 19 deletions

diff --git a/mrbgems/mruby-compiler/core/codegen.c b/mrbgems/mruby-compiler/core/codegen.c
index ed8fc3150..c0986893c 100644
--- a/mrbgems/mruby-compiler/core/codegen.c
+++ b/mrbgems/mruby-compiler/core/codegen.c
@@ -291,7 +291,7 @@ on_eval(codegen_scope *s)
 }
 
 struct mrb_insn_data
-mrb_decode_insn(mrb_code *pc)
+mrb_decode_insn(const mrb_code *pc)
 {
   struct mrb_insn_data data = { 0 };
   mrb_code insn = READ_B();
@@ -956,7 +956,12 @@ gen_values(codegen_scope *s, node *t, int val, int extra)
         }
         else {
           pop_n(n);
-          genop_2(s, OP_ARRAY, cursp(), n);
+          if (n == 0 && is_splat) {
+            genop_1(s, OP_LOADNIL, cursp());
+          }
+          else {
+            genop_2(s, OP_ARRAY, cursp(), n);
+          }
           push();
           codegen(s, t->car, VAL);
           pop(); pop();
@@ -1553,7 +1558,7 @@ codegen(codegen_scope *s, node *tree, int val)
 
   case NODE_IF:
     {
-      int pos1, pos2;
+      int pos1, pos2, nil_p = FALSE;
       node *elsepart = tree->cdr->cdr->car;
 
       if (!tree->car) {
@@ -1570,32 +1575,59 @@ codegen(codegen_scope *s, node *tree, int val)
       case NODE_NIL:
         codegen(s, elsepart, val);
         goto exit;
+      case NODE_CALL:
+        {
+          node *n = tree->car->cdr;
+          mrb_sym mid = nsym(n->cdr->car);
+          mrb_sym mnil = mrb_intern_lit(s->mrb, "nil?");
+          if (mid == mnil && n->cdr->cdr->car == NULL) {
+            nil_p = TRUE;
+            codegen(s, n->car, VAL);
+          }
+        }
+        break;
+      }
+      if (!nil_p) {
+        codegen(s, tree->car, VAL);
       }
-      codegen(s, tree->car, VAL);
       pop();
-      pos1 = genjmp2(s, OP_JMPNOT, cursp(), 0, val);
-
-      codegen(s, tree->cdr->car, val);
-      if (elsepart) {
+      if (val || tree->cdr->car) {
+        if (nil_p) {
+          pos2 = genjmp2(s, OP_JMPNIL, cursp(), 0, val);
+          pos1 = genjmp(s, OP_JMP, 0);
+          dispatch(s, pos2);
+        }
+        else {
+          pos1 = genjmp2(s, OP_JMPNOT, cursp(), 0, val);
+        }
+        codegen(s, tree->cdr->car, val);
         if (val) pop();
-        pos2 = genjmp(s, OP_JMP, 0);
-        dispatch(s, pos1);
-        codegen(s, elsepart, val);
-        dispatch(s, pos2);
-      }
-      else {
-        if (val) {
-          pop();
+        if (elsepart || val) {
           pos2 = genjmp(s, OP_JMP, 0);
           dispatch(s, pos1);
-          genop_1(s, OP_LOADNIL, cursp());
+          codegen(s, elsepart, val);
           dispatch(s, pos2);
-          push();
         }
         else {
           dispatch(s, pos1);
         }
       }
+      else {                    /* empty then-part */
+        if (elsepart) {
+          if (nil_p) {
+            pos1 = genjmp2(s, OP_JMPNIL, cursp(), 0, val);
+          }
+          else {
+            pos1 = genjmp2(s, OP_JMPIF, cursp(), 0, val);
+          }
+          codegen(s, elsepart, val);
+          dispatch(s, pos1);
+        }
+        else if (val && !nil_p) {
+          genop_1(s, OP_LOADNIL, cursp());
+          push();
+        }
+      }
     }
     break;
 
@@ -2373,7 +2405,7 @@ codegen(codegen_scope *s, node *tree, int val)
       mrb_value str;
       int sym;
 
-      str = mrb_format(mrb, "$%S", mrb_fixnum_value(nint(tree)));
+      str = mrb_format(mrb, "$%d", nint(tree));
       sym = new_sym(s, mrb_intern_str(mrb, str));
       genop_2(s, OP_GETGV, cursp(), sym);
       push();