diff --git a/lib/parser_inline.js b/lib/parser_inline.js
index 58f8351..a19a5de 100644
--- a/lib/parser_inline.js
+++ b/lib/parser_inline.js
@@ -48,14 +48,15 @@ function ParserInline() {
 // returns `true` if any rule reported success
 //
 ParserInline.prototype.skipToken = function (state) {
-  var i, cached_pos, pos = state.pos,
+  var i, pos = state.pos,
       rules = this.ruler.getRules(''),
       len = rules.length,
-      maxNesting = state.md.options.maxNesting;
+      maxNesting = state.md.options.maxNesting,
+      cache = state.cache;
 
 
-  if ((cached_pos = state.cacheGet(pos)) > 0) {
-    state.pos = cached_pos;
+  if (typeof cache[pos] !== 'undefined') {
+    state.pos = cache[pos];
     return;
   }
 
@@ -63,14 +64,14 @@ ParserInline.prototype.skipToken = function (state) {
   if (state.level < maxNesting) {
     for (i = 0; i < len; i++) {
       if (rules[i](state, true)) {
-        state.cacheSet(pos, state.pos);
+        cache[pos] = state.pos;
         return;
       }
     }
   }
 
   state.pos++;
-  state.cacheSet(pos, state.pos);
+  cache[pos] = state.pos;
 };
 
 
diff --git a/lib/renderer.js b/lib/renderer.js
index 201d7a0..ff4c76e 100644
--- a/lib/renderer.js
+++ b/lib/renderer.js
@@ -18,6 +18,11 @@ var escapeHtml      = require('./common/utils').escapeHtml;
 var default_rules = {};
 
 
+default_rules.code_inline = function (tokens, idx /*, options, env */) {
+  return '<code>' + escapeHtml(tokens[idx].content) + '</code>';
+};
+
+
 default_rules.code_block = function (tokens, idx /*, options, env */) {
   return '<pre><code>' + escapeHtml(tokens[idx].content) + '</code></pre>\n';
 };
@@ -176,10 +181,12 @@ Renderer.prototype.renderToken = function renderToken(tokens, idx, options) {
   result += (token.nesting === -1 ? '</' : '<') + token.tag;
 
   // Encode attributes, e.g. `<img src="foo"`
-  result += this.renderAttrs(token.attrs);
+  if (typeof token.attrs !== 'undefined') {
+    result += this.renderAttrs(token.attrs);
+  }
 
   // Add a slash for self-closing tags, e.g. `<img src="foo" /`
-  if (token.nesting === 0 && options.xhtmlOut && token.content === null) {
+  if (token.nesting === 0 && options.xhtmlOut) {
     result += ' /';
   }
 
@@ -205,11 +212,6 @@ Renderer.prototype.renderToken = function renderToken(tokens, idx, options) {
     }
   }
 
-  // If it's self-contained token, add its contents + closing tag
-  if (token.nesting === 0 && token.content !== null) {
-    result += '>' + escapeHtml(token.content) + '</' + token.tag;
-  }
-
   result += needLf ? '>\n' : '>';
 
   return result;
diff --git a/lib/rules_block/heading.js b/lib/rules_block/heading.js
index 48bd6b9..1cf4723 100644
--- a/lib/rules_block/heading.js
+++ b/lib/rules_block/heading.js
@@ -35,7 +35,7 @@ module.exports = function heading(state, startLine, endLine, silent) {
   state.line = startLine + 1;
 
   token        = state.push('heading_open', 'h' + String(level), 1);
-  token.markup = Array(level + 1).join('#');
+  token.markup = '########'.slice(0, level);
   token.map    = [ startLine, state.line ];
 
   token          = state.push('inline', '', 0);
@@ -44,7 +44,7 @@ module.exports = function heading(state, startLine, endLine, silent) {
   token.children = [];
 
   token        = state.push('heading_close', 'h' + String(level), -1);
-  token.markup = Array(level + 1).join('#');
+  token.markup = '########'.slice(0, level);
 
   return true;
 };
diff --git a/lib/rules_core/linkify.js b/lib/rules_core/linkify.js
index 7c99a7c..d55c8e7 100644
--- a/lib/rules_core/linkify.js
+++ b/lib/rules_core/linkify.js
@@ -26,7 +26,10 @@ module.exports = function linkify(state) {
   if (!state.md.options.linkify) { return; }
 
   for (j = 0, l = blockTokens.length; j < l; j++) {
-    if (blockTokens[j].type !== 'inline') { continue; }
+    if (blockTokens[j].type !== 'inline' ||
+        !state.md.linkify.test(blockTokens[j].content)) {
+      continue;
+    }
 
     tokens = blockTokens[j].children;
 
diff --git a/lib/rules_core/smartquotes.js b/lib/rules_core/smartquotes.js
index c0a611b..2466e78 100644
--- a/lib/rules_core/smartquotes.js
+++ b/lib/rules_core/smartquotes.js
@@ -29,7 +29,10 @@ module.exports = function smartquotes(state) {
 
   for (blkIdx = state.tokens.length - 1; blkIdx >= 0; blkIdx--) {
 
-    if (state.tokens[blkIdx].type !== 'inline') { continue; }
+    if (state.tokens[blkIdx].type !== 'inline' ||
+        !QUOTE_TEST_RE.test(state.tokens[blkIdx].content)) {
+      continue;
+    }
 
     tokens = state.tokens[blkIdx].children;
     stack.length = 0;
diff --git a/lib/rules_inline/autolink.js b/lib/rules_inline/autolink.js
index f3fa67b..186355f 100644
--- a/lib/rules_inline/autolink.js
+++ b/lib/rules_inline/autolink.js
@@ -21,9 +21,9 @@ module.exports = function autolink(state, silent) {
 
   if (tail.indexOf('>') < 0) { return false; }
 
-  linkMatch = tail.match(AUTOLINK_RE);
+  if (AUTOLINK_RE.test(tail)) {
+    linkMatch = tail.match(AUTOLINK_RE);
 
-  if (linkMatch) {
     if (url_schemas.indexOf(linkMatch[1].toLowerCase()) < 0) { return false; }
 
     url = linkMatch[0].slice(1, -1);
@@ -44,9 +44,8 @@ module.exports = function autolink(state, silent) {
     return true;
   }
 
-  emailMatch = tail.match(EMAIL_RE);
-
-  if (emailMatch) {
+  if (EMAIL_RE.test(tail)) {
+    emailMatch = tail.match(EMAIL_RE);
 
     url = emailMatch[0].slice(1, -1);
 
diff --git a/lib/rules_inline/state_inline.js b/lib/rules_inline/state_inline.js
index fdc26b4..2a7a05f 100644
--- a/lib/rules_inline/state_inline.js
+++ b/lib/rules_inline/state_inline.js
@@ -17,7 +17,7 @@ function StateInline(src, md, env, outTokens) {
   this.pending = '';
   this.pendingLevel = 0;
 
-  this.cache = [];        // Stores { start: end } pairs. Useful for backtrack
+  this.cache = {};        // Stores { start: end } pairs. Useful for backtrack
                           // optimization of pairs parse (emphasis, strikes).
 }
 
@@ -54,24 +54,4 @@ StateInline.prototype.push = function (type, tag, nesting) {
 };
 
 
-// Store value to cache.
-// !!! Implementation has parser-specific optimizations
-// !!! keys MUST be integer, >= 0; values MUST be integer, > 0
-//
-StateInline.prototype.cacheSet = function (key, val) {
-  for (var i = this.cache.length; i <= key; i++) {
-    this.cache.push(0);
-  }
-
-  this.cache[key] = val;
-};
-
-
-// Get cache value
-//
-StateInline.prototype.cacheGet = function (key) {
-  return key < this.cache.length ? this.cache[key] : 0;
-};
-
-
 module.exports = StateInline;
diff --git a/lib/token.js b/lib/token.js
index 3a8451d..0daa178 100644
--- a/lib/token.js
+++ b/lib/token.js
@@ -72,7 +72,7 @@ function Token(type, tag, nesting) {
    * In a case of self-closing tag (code, html, fence, etc.),
    * it has contents of this tag.
    **/
-  this.content  = null;
+  this.content  = '';
 
   /**
    * Token#markup -> String
@@ -86,7 +86,7 @@ function Token(type, tag, nesting) {
    *
    * fence infostring
    **/
-  this.info     = null;
+  this.info     = '';
 
   /**
    * Token#block -> Boolean