diff --git a/src/lib/libfs.js b/src/lib/libfs.js
index 65674a584ef8b..b317f55d4cbc7 100644
--- a/src/lib/libfs.js
+++ b/src/lib/libfs.js
@@ -376,9 +376,11 @@ FS.staticInit();`;
       // return 0 if any user, group or owner bits are set.
       if (perms.includes('r') && !(node.mode & {{{ cDefs.S_IRUGO }}})) {
         return {{{ cDefs.EACCES }}};
-      } else if (perms.includes('w') && !(node.mode & {{{ cDefs.S_IWUGO }}})) {
+      }
+      if (perms.includes('w') && !(node.mode & {{{ cDefs.S_IWUGO }}})) {
         return {{{ cDefs.EACCES }}};
-      } else if (perms.includes('x') && !(node.mode & {{{ cDefs.S_IXUGO }}})) {
+      }
+      if (perms.includes('x') && !(node.mode & {{{ cDefs.S_IXUGO }}})) {
         return {{{ cDefs.EACCES }}};
       }
       return 0;
@@ -419,10 +421,8 @@ FS.staticInit();`;
         if (FS.isRoot(node) || FS.getPath(node) === FS.cwd()) {
           return {{{ cDefs.EBUSY }}};
         }
-      } else {
-        if (FS.isDir(node.mode)) {
-          return {{{ cDefs.EISDIR }}};
-        }
+      } else if (FS.isDir(node.mode)) {
+        return {{{ cDefs.EISDIR }}};
       }
       return 0;
     },
@@ -432,13 +432,16 @@ FS.staticInit();`;
       }
       if (FS.isLink(node.mode)) {
         return {{{ cDefs.ELOOP }}};
-      } else if (FS.isDir(node.mode)) {
-        if (FS.flagsToPermissionString(flags) !== 'r' // opening for write
-            || (flags & ({{{ cDefs.O_TRUNC }}} | {{{ cDefs.O_CREAT }}}))) { // TODO: check for O_SEARCH? (== search for dir only)
+      }
+      var mode = FS.flagsToPermissionString(flags);
+      if (FS.isDir(node.mode)) {
+        // opening for write
+        // TODO: check for O_SEARCH? (== search for dir only)
+        if (mode !== 'r' || (flags & ({{{ cDefs.O_TRUNC }}} | {{{ cDefs.O_CREAT }}}))) {
           return {{{ cDefs.EISDIR }}};
         }
       }
-      return FS.nodePermissions(node, FS.flagsToPermissionString(flags));
+      return FS.nodePermissions(node, mode);
     },
     checkOpExists(op, err) {
       if (!op) {
diff --git a/test/codesize/test_codesize_cxx_ctors1.json b/test/codesize/test_codesize_cxx_ctors1.json
index 95216d3081c13..1c8129ca845cf 100644
--- a/test/codesize/test_codesize_cxx_ctors1.json
+++ b/test/codesize/test_codesize_cxx_ctors1.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19664,
-  "a.out.js.gz": 8146,
+  "a.out.js": 19602,
+  "a.out.js.gz": 8132,
   "a.out.nodebug.wasm": 132844,
   "a.out.nodebug.wasm.gz": 49884,
-  "total": 152508,
-  "total_gz": 58030,
+  "total": 152446,
+  "total_gz": 58016,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_ctors2.json b/test/codesize/test_codesize_cxx_ctors2.json
index 48936da20a1ec..41cd79a8400ca 100644
--- a/test/codesize/test_codesize_cxx_ctors2.json
+++ b/test/codesize/test_codesize_cxx_ctors2.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19641,
-  "a.out.js.gz": 8133,
+  "a.out.js": 19579,
+  "a.out.js.gz": 8118,
   "a.out.nodebug.wasm": 132264,
   "a.out.nodebug.wasm.gz": 49542,
-  "total": 151905,
-  "total_gz": 57675,
+  "total": 151843,
+  "total_gz": 57660,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_cxx_except.json b/test/codesize/test_codesize_cxx_except.json
index 92eb77122cb42..9be7f7ac3e551 100644
--- a/test/codesize/test_codesize_cxx_except.json
+++ b/test/codesize/test_codesize_cxx_except.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23325,
-  "a.out.js.gz": 9127,
+  "a.out.js": 23263,
+  "a.out.js.gz": 9109,
   "a.out.nodebug.wasm": 172774,
   "a.out.nodebug.wasm.gz": 57405,
-  "total": 196099,
-  "total_gz": 66532,
+  "total": 196037,
+  "total_gz": 66514,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_except_wasm.json b/test/codesize/test_codesize_cxx_except_wasm.json
index 47b46492f6198..e75001f0e9542 100644
--- a/test/codesize/test_codesize_cxx_except_wasm.json
+++ b/test/codesize/test_codesize_cxx_except_wasm.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19475,
-  "a.out.js.gz": 8072,
+  "a.out.js": 19413,
+  "a.out.js.gz": 8054,
   "a.out.nodebug.wasm": 148169,
   "a.out.nodebug.wasm.gz": 55285,
-  "total": 167644,
-  "total_gz": 63357,
+  "total": 167582,
+  "total_gz": 63339,
   "sent": [
     "_abort_js",
     "_tzset_js",
diff --git a/test/codesize/test_codesize_cxx_except_wasm_legacy.json b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
index 91e7d7962c513..b6507346a16b6 100644
--- a/test/codesize/test_codesize_cxx_except_wasm_legacy.json
+++ b/test/codesize/test_codesize_cxx_except_wasm_legacy.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19549,
-  "a.out.js.gz": 8091,
+  "a.out.js": 19487,
+  "a.out.js.gz": 8074,
   "a.out.nodebug.wasm": 145975,
   "a.out.nodebug.wasm.gz": 54915,
-  "total": 165524,
-  "total_gz": 63006,
+  "total": 165462,
+  "total_gz": 62989,
   "sent": [
     "_abort_js",
     "_tzset_js",
diff --git a/test/codesize/test_codesize_cxx_lto.json b/test/codesize/test_codesize_cxx_lto.json
index a0ba138c38f43..c1a578dd35d89 100644
--- a/test/codesize/test_codesize_cxx_lto.json
+++ b/test/codesize/test_codesize_cxx_lto.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19011,
-  "a.out.js.gz": 7826,
+  "a.out.js": 18949,
+  "a.out.js.gz": 7812,
   "a.out.nodebug.wasm": 102076,
   "a.out.nodebug.wasm.gz": 39428,
-  "total": 121087,
-  "total_gz": 47254,
+  "total": 121025,
+  "total_gz": 47240,
   "sent": [
     "a (emscripten_resize_heap)",
     "b (_setitimer_js)",
diff --git a/test/codesize/test_codesize_cxx_mangle.json b/test/codesize/test_codesize_cxx_mangle.json
index 30a9a72863718..713ae0455d4c5 100644
--- a/test/codesize/test_codesize_cxx_mangle.json
+++ b/test/codesize/test_codesize_cxx_mangle.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 23375,
-  "a.out.js.gz": 9147,
+  "a.out.js": 23313,
+  "a.out.js.gz": 9128,
   "a.out.nodebug.wasm": 239224,
   "a.out.nodebug.wasm.gz": 79795,
-  "total": 262599,
-  "total_gz": 88942,
+  "total": 262537,
+  "total_gz": 88923,
   "sent": [
     "__cxa_begin_catch",
     "__cxa_end_catch",
diff --git a/test/codesize/test_codesize_cxx_noexcept.json b/test/codesize/test_codesize_cxx_noexcept.json
index 6df78e553c6c6..2a1a664f97065 100644
--- a/test/codesize/test_codesize_cxx_noexcept.json
+++ b/test/codesize/test_codesize_cxx_noexcept.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 19664,
-  "a.out.js.gz": 8146,
+  "a.out.js": 19602,
+  "a.out.js.gz": 8132,
   "a.out.nodebug.wasm": 134851,
   "a.out.nodebug.wasm.gz": 50712,
-  "total": 154515,
-  "total_gz": 58858,
+  "total": 154453,
+  "total_gz": 58844,
   "sent": [
     "__cxa_throw",
     "_abort_js",
diff --git a/test/codesize/test_codesize_file_preload.expected.js b/test/codesize/test_codesize_file_preload.expected.js
index 1030cbe8fad3a..089058d9e9f84 100644
--- a/test/codesize/test_codesize_file_preload.expected.js
+++ b/test/codesize/test_codesize_file_preload.expected.js
@@ -1638,9 +1638,11 @@ var FS = {
     // return 0 if any user, group or owner bits are set.
     if (perms.includes("r") && !(node.mode & 292)) {
       return 2;
-    } else if (perms.includes("w") && !(node.mode & 146)) {
+    }
+    if (perms.includes("w") && !(node.mode & 146)) {
       return 2;
-    } else if (perms.includes("x") && !(node.mode & 73)) {
+    }
+    if (perms.includes("x") && !(node.mode & 73)) {
       return 2;
     }
     return 0;
@@ -1680,10 +1682,8 @@ var FS = {
       if (FS.isRoot(node) || FS.getPath(node) === FS.cwd()) {
         return 10;
       }
-    } else {
-      if (FS.isDir(node.mode)) {
-        return 31;
-      }
+    } else if (FS.isDir(node.mode)) {
+      return 31;
     }
     return 0;
   },
@@ -1693,13 +1693,16 @@ var FS = {
     }
     if (FS.isLink(node.mode)) {
       return 32;
-    } else if (FS.isDir(node.mode)) {
-      if (FS.flagsToPermissionString(flags) !== "r" || (flags & (512 | 64))) {
-        // TODO: check for O_SEARCH? (== search for dir only)
+    }
+    var mode = FS.flagsToPermissionString(flags);
+    if (FS.isDir(node.mode)) {
+      // opening for write
+      // TODO: check for O_SEARCH? (== search for dir only)
+      if (mode !== "r" || (flags & (512 | 64))) {
         return 31;
       }
     }
-    return FS.nodePermissions(node, FS.flagsToPermissionString(flags));
+    return FS.nodePermissions(node, mode);
   },
   checkOpExists(op, err) {
     if (!op) {
diff --git a/test/codesize/test_codesize_file_preload.json b/test/codesize/test_codesize_file_preload.json
index f3f9b8b4c2060..63eb5b217a6c2 100644
--- a/test/codesize/test_codesize_file_preload.json
+++ b/test/codesize/test_codesize_file_preload.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 22571,
-  "a.out.js.gz": 9339,
+  "a.out.js": 22509,
+  "a.out.js.gz": 9332,
   "a.out.nodebug.wasm": 1681,
   "a.out.nodebug.wasm.gz": 960,
-  "total": 24252,
-  "total_gz": 10299,
+  "total": 24190,
+  "total_gz": 10292,
   "sent": [
     "a (fd_write)"
   ],
diff --git a/test/codesize/test_codesize_files_js_fs.json b/test/codesize/test_codesize_files_js_fs.json
index 394c9faa62526..d9f4d69cd1c85 100644
--- a/test/codesize/test_codesize_files_js_fs.json
+++ b/test/codesize/test_codesize_files_js_fs.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 18283,
-  "a.out.js.gz": 7464,
+  "a.out.js": 18220,
+  "a.out.js.gz": 7450,
   "a.out.nodebug.wasm": 381,
   "a.out.nodebug.wasm.gz": 260,
-  "total": 18664,
-  "total_gz": 7724,
+  "total": 18601,
+  "total_gz": 7710,
   "sent": [
     "a (fd_write)",
     "b (fd_read)",
diff --git a/test/codesize/test_codesize_hello_dylink.json b/test/codesize/test_codesize_hello_dylink.json
index e3faee66565a1..2b1d5222fed76 100644
--- a/test/codesize/test_codesize_hello_dylink.json
+++ b/test/codesize/test_codesize_hello_dylink.json
@@ -1,10 +1,10 @@
 {
-  "a.out.js": 26705,
-  "a.out.js.gz": 11396,
+  "a.out.js": 26642,
+  "a.out.js.gz": 11380,
   "a.out.nodebug.wasm": 17730,
   "a.out.nodebug.wasm.gz": 8957,
-  "total": 44435,
-  "total_gz": 20353,
+  "total": 44372,
+  "total_gz": 20337,
   "sent": [
     "__syscall_stat64",
     "emscripten_resize_heap",
diff --git a/test/codesize/test_codesize_hello_dylink_all.json b/test/codesize/test_codesize_hello_dylink_all.json
index 6cef4a1d3e01e..c4b3e1e6026d8 100644
--- a/test/codesize/test_codesize_hello_dylink_all.json
+++ b/test/codesize/test_codesize_hello_dylink_all.json
@@ -1,7 +1,7 @@
 {
-  "a.out.js": 244882,
+  "a.out.js": 244819,
   "a.out.nodebug.wasm": 577863,
-  "total": 822745,
+  "total": 822682,
   "sent": [
     "IMG_Init",
     "IMG_Load",