Tweak codegen to merge if branches

Author: bobzhang

jscomp/core/js_stmt_make.ml

@@ -213,18 +213,16 @@ let rec if_ ?comment  ?declaration ?else_ (e : J.expression) (then_ : J.block)
   let common_prefix_blocks = ref [] in 
   let add_prefix b = common_prefix_blocks := b :: !common_prefix_blocks in 
   let rec aux ?comment (e : J.expression) (ifso : J.block) (ifnot : J.block ): t  =
-    match e.expression_desc with 
-    | Bool boolean -> 
+    match e.expression_desc,ifnot  with 
+    | Bool boolean, _ -> 
       block (if boolean then ifso else ifnot) 
-    | Js_not pred_not
+    | Js_not pred_not, (_::_)
       -> aux ?comment pred_not ifnot ifso
     | _ -> 
       match ifso, ifnot with 
       |  [], [] -> exp e 
       |  [], _ ->
-        {
-          statement_desc = If ( E.not e, ifnot, []); comment
-        }
+         aux ?comment (E.not e) ifnot [] (*Make sure no infinite loop*)        
       | [ {statement_desc = Return {return_value = ret_ifso; _}; _}], 
         [ {statement_desc = Return {return_value = ret_ifnot; _}; _} as _ifnot_stmt]
         ->      

jscomp/test/flow_parser_reg_test.js

@@ -10140,11 +10140,8 @@ function directive_parse(token_with_comments, lexbuf) {
             var value_v = query(curr_loc, curr_token[0]);
             return token_op(calc, (function (e) {
                           push(e);
-                          if (typeof value_v !== "number") {
-                            if (!value_v.tag) {
-                              return value_v[0];
-                            }
-                            
+                          if (typeof value_v !== "number" && !value_v.tag) {
+                            return value_v[0];
                           }
                           var ty = type_of_directive(value_v);
                           throw [

jscomp/test/ocaml_parsetree_test.js

@@ -2941,11 +2941,8 @@ function endline(s) {
 }
 
 function gen_pp_field(field_type) {
-  if (typeof field_type !== "number") {
-    if (field_type.tag) {
-      return function_name_of_user_defined("pp", field_type[0]);
-    }
-    
+  if (typeof field_type !== "number" && field_type.tag) {
+    return function_name_of_user_defined("pp", field_type[0]);
   }
   return Curry._1(Printf.sprintf(/* Format */[
                   /* String_literal */Block.__(11, [

jscomp/test/ocaml_proto_test.js

@@ -4453,11 +4453,8 @@ function extension(loc, attrs, a) {
 
 function force_poly(t) {
   var match = t[/* ptyp_desc */0];
-  if (typeof match !== "number") {
-    if (match.tag === 8) {
-      return t;
-    }
-    
+  if (typeof match !== "number" && match.tag === 8) {
+    return t;
   }
   return poly(t[/* ptyp_loc */1], undefined, /* [] */0, t);
 }
@@ -12881,11 +12878,8 @@ function directive_parse(token_with_comments, lexbuf) {
             var value_v = query(curr_loc, curr_token[0]);
             return token_op(calc, (function (e) {
                           push(e);
-                          if (typeof value_v !== "number") {
-                            if (!value_v.tag) {
-                              return value_v[0];
-                            }
-                            
+                          if (typeof value_v !== "number" && !value_v.tag) {
+                            return value_v[0];
                           }
                           var ty = type_of_directive(value_v);
                           throw [