29 files changed, 879 insertions, 235 deletions

diff --git a/AUTHORS b/AUTHORS
index 0b8fdf33..6a28c205 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -107,3 +107,4 @@ a license to everyone to use it as detailed in LICENSE.)
 * Michael Tirado <icetooth333@gmail.com>
 * Ben Noordhuis <info@bnoordhuis.nl>
 * Bob Roberts <bobroberts177@gmail.com>
+* John Vilk <jvilk@cs.umass.edu>
diff --git a/emscripten.py b/emscripten.py
index 5576baba..7c9cbdbe 100755
--- a/emscripten.py
+++ b/emscripten.py
@@ -11,6 +11,7 @@ headers, for the libc implementation in JS).
 
 import os, sys, json, optparse, subprocess, re, time, multiprocessing, string, logging
 
+from tools import shared
 from tools import jsrun, cache as cache_module, tempfiles
 from tools.response_file import read_response_file
 
@@ -25,7 +26,6 @@ def get_configuration():
   if hasattr(get_configuration, 'configuration'):
     return get_configuration.configuration
 
-  from tools import shared
   configuration = shared.Configuration(environ=os.environ)
   get_configuration.configuration = configuration
   return configuration
@@ -425,8 +425,8 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
       Counter.i += 1
       bad = 'b' + str(i)
       params = ','.join(['p%d' % p for p in range(len(sig)-1)])
-      coercions = ';'.join(['p%d = %sp%d%s' % (p, '+' if sig[p+1] != 'i' else '', p, '' if sig[p+1] != 'i' else '|0') for p in range(len(sig)-1)]) + ';'
-      ret = '' if sig[0] == 'v' else ('return %s0' % ('+' if sig[0] != 'i' else ''))
+      coercions = ';'.join(['p%d = %s' % (p, shared.JS.make_coercion('p%d' % p, sig[p+1], settings)) for p in range(len(sig)-1)]) + ';'
+      ret = '' if sig[0] == 'v' else ('return %s' % shared.JS.make_initializer(sig[0], settings))
       start = raw.index('[')
       end = raw.rindex(']')
       body = raw[start+1:end].split(',')
@@ -451,7 +451,7 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
     math_envs = ['Math.min'] # TODO: move min to maths
     asm_setup += '\n'.join(['var %s = %s;' % (f.replace('.', '_'), f) for f in math_envs])
 
-    if settings['TO_FLOAT32']: maths += ['Math.toFloat32']
+    if settings['PRECISE_F32']: maths += ['Math.fround']
 
     basic_funcs = ['abort', 'assert', 'asmPrintInt', 'asmPrintFloat'] + [m.replace('.', '_') for m in math_envs]
     if settings['RESERVED_FUNCTION_POINTERS'] > 0: basic_funcs.append('jsCall')
@@ -476,18 +476,14 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
 
     asm_runtime_funcs = ['stackAlloc', 'stackSave', 'stackRestore', 'setThrew'] + ['setTempRet%d' % i for i in range(10)]
     # function tables
-    def asm_coerce(value, sig):
-      if sig == 'v': return value
-      return ('+' if sig != 'i' else '') + value + ('|0' if sig == 'i' else '')
-
     function_tables = ['dynCall_' + table for table in last_forwarded_json['Functions']['tables']]
     function_tables_impls = []
 
     for sig in last_forwarded_json['Functions']['tables'].iterkeys():
       args = ','.join(['a' + str(i) for i in range(1, len(sig))])
-      arg_coercions = ' '.join(['a' + str(i) + '=' + asm_coerce('a' + str(i), sig[i]) + ';' for i in range(1, len(sig))])
-      coerced_args = ','.join([asm_coerce('a' + str(i), sig[i]) for i in range(1, len(sig))])
-      ret = ('return ' if sig[0] != 'v' else '') + asm_coerce('FUNCTION_TABLE_%s[index&{{{ FTM_%s }}}](%s)' % (sig, sig, coerced_args), sig[0])
+      arg_coercions = ' '.join(['a' + str(i) + '=' + shared.JS.make_coercion('a' + str(i), sig[i], settings) + ';' for i in range(1, len(sig))])
+      coerced_args = ','.join([shared.JS.make_coercion('a' + str(i), sig[i], settings) for i in range(1, len(sig))])
+      ret = ('return ' if sig[0] != 'v' else '') + shared.JS.make_coercion('FUNCTION_TABLE_%s[index&{{{ FTM_%s }}}](%s)' % (sig, sig, coerced_args), sig[0], settings)
       function_tables_impls.append('''
   function dynCall_%s(index%s%s) {
     index = index|0;
@@ -497,7 +493,7 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
 ''' % (sig, ',' if len(sig) > 1 else '', args, arg_coercions, ret))
 
       for i in range(settings['RESERVED_FUNCTION_POINTERS']):
-        jsret = ('return ' if sig[0] != 'v' else '') + asm_coerce('jsCall(%d%s%s)' % (i, ',' if coerced_args else '', coerced_args), sig[0])
+        jsret = ('return ' if sig[0] != 'v' else '') + shared.JS.make_coercion('jsCall(%d%s%s)' % (i, ',' if coerced_args else '', coerced_args), sig[0], settings)
         function_tables_impls.append('''
   function jsCall_%s_%s(%s) {
     %s
@@ -505,7 +501,6 @@ def emscript(infile, settings, outfile, libraries=[], compiler_engine=None,
   }
 
 ''' % (sig, i, args, arg_coercions, jsret))
-      from tools import shared
       shared.Settings.copy(settings)
       asm_setup += '\n' + shared.JS.make_invoke(sig) + '\n'
       basic_funcs.append('invoke_%s' % sig)
@@ -585,7 +580,7 @@ var asm = (function(global, env, buffer) {
   var undef = 0;
   var tempInt = 0, tempBigInt = 0, tempBigIntP = 0, tempBigIntS = 0, tempBigIntR = 0.0, tempBigIntI = 0, tempBigIntD = 0, tempValue = 0, tempDouble = 0.0;
 ''' + ''.join(['''
-  var tempRet%d = 0;''' % i for i in range(10)]) + '\n' + asm_global_funcs + '''
+  var tempRet%d = 0;''' % i for i in range(10)]) + '\n' + asm_global_funcs] + ['  var tempFloat = %s;\n' % ('Math_fround(0)' if settings.get('PRECISE_F32') else '0.0')] + ['''
 // EMSCRIPTEN_START_FUNCS
 function stackAlloc(size) {
   size = size|0;
@@ -727,14 +722,12 @@ def main(args, compiler_engine, cache, jcache, relooper, temp_files, DEBUG, DEBU
       relooper = cache.get_path('relooper.js')
     settings.setdefault('RELOOPER', relooper)
     if not os.path.exists(relooper):
-      from tools import shared
       shared.Building.ensure_relooper(relooper)
   
   settings.setdefault('STRUCT_INFO', cache.get_path('struct_info.compiled.json'))
   struct_info = settings.get('STRUCT_INFO')
   
   if not os.path.exists(struct_info):
-    from tools import shared
     shared.Building.ensure_struct_info(struct_info)
   
   emscript(args.infile, settings, args.outfile, libraries, compiler_engine=compiler_engine,
@@ -833,7 +826,6 @@ WARNING: You should normally never use this! Use emcc instead.
     temp_files = tempfiles.TempFiles(temp_dir)
 
   if keywords.compiler is None:
-    from tools import shared
     keywords.compiler = shared.COMPILER_ENGINE
 
   if keywords.verbose is None:
diff --git a/src/intertyper.js b/src/intertyper.js
index fceeb38d..fa53c652 100644
--- a/src/intertyper.js
+++ b/src/intertyper.js
@@ -680,6 +680,9 @@ function intertyper(lines, sidePass, baseLineNums) {
           args.push(ident);
         });
       }
+      item.ident = expandLLVMString(item.ident).replace(/(#[^\n]*)/g, function(m) {
+        return '/* ' + m.substr(1) + ' */'; // fix asm comments to js comments
+      });
       if (item.assignTo) item.ident = 'return ' + item.ident;
       item.ident = '(function(' + params + ') { ' + item.ident + ' })(' + args + ');';
       return { ret: item, item: item };
diff --git a/src/jsifier.js b/src/jsifier.js
index 0da48a8c..97317756 100644
--- a/src/jsifier.js
+++ b/src/jsifier.js
@@ -756,14 +756,7 @@ function JSify(data, functionsOnly, givenFunctions) {
           if (func.setjmpTable && !ASM_JS) {
             ret += ' } catch(e) { if (!e.longjmp || !(e.id in mySetjmpIds)) throw(e); setjmpTable[setjmpLabels[e.id]](e.value) }';
           }
-          if (ASM_JS && func.returnType !== 'void') {
-            // Add a return
-            if (func.returnType in Runtime.FLOAT_TYPES) {
-              ret += ' return +0;\n';
-            } else {
-              ret += ' return 0;\n';
-            }
-          }
+          if (ASM_JS && func.returnType !== 'void') ret += '  return ' + asmInitializer(func.returnType) + ';\n'; // Add a return
         } else {
           ret += (SHOW_LABELS ? indent + '/* ' + block.entries[0] + ' */' : '') + '\n' + getLabelLines(block.labels[0]);
         }
@@ -833,11 +826,7 @@ function JSify(data, functionsOnly, givenFunctions) {
       var lastReturn = func.JS.lastIndexOf('return ');
       if ((lastCurly < 0 && lastReturn < 0) || // no control flow, no return
           (lastCurly >= 0 && lastReturn < lastCurly)) { // control flow, no return past last join
-        if (func.returnType in Runtime.FLOAT_TYPES) {
-          func.JS += ' return +0;\n';
-        } else {
-          func.JS += ' return 0;\n';
-        }
+        func.JS += '  return ' + asmInitializer(func.returnType) + ';\n';
       }
     }
     func.JS += '}\n';
@@ -1337,7 +1326,7 @@ function JSify(data, functionsOnly, givenFunctions) {
         if (isNumber(item.ident)) {
           // Direct read from a memory address; this may be an intentional segfault, if not, it is a bug in the source
           if (ASM_JS) {
-            return asmCoercion('abort(' + item.ident + ')', item.type);
+            return asmFFICoercion('abort(' + item.ident + ')', item.type);
           } else {
             item.assignTo = null;
             return 'throw "fault on read from ' + item.ident + '";';
@@ -1514,8 +1503,10 @@ function JSify(data, functionsOnly, givenFunctions) {
 
     args = args.map(function(arg, i) { return indexizeFunctions(arg, argsTypes[i]) });
     if (ASM_JS) {
-      if (shortident in Functions.libraryFunctions || simpleIdent in Functions.libraryFunctions || byPointerForced || invoke || extCall || funcData.setjmpTable) {
-        args = args.map(function(arg, i) { return asmCoercion(arg, argsTypes[i]) });
+      var ffiCall = (shortident in Functions.libraryFunctions || simpleIdent in Functions.libraryFunctions || byPointerForced || invoke || extCall || funcData.setjmpTable) &&
+                    !(simpleIdent in JS_MATH_BUILTINS);
+      if (ffiCall) {
+        args = args.map(function(arg, i) { return asmCoercion(arg, ensureValidFFIType(argsTypes[i])) });
       } else {
         args = args.map(function(arg, i) { return asmEnsureFloat(arg, argsTypes[i]) });
       }
@@ -1592,7 +1583,7 @@ function JSify(data, functionsOnly, givenFunctions) {
       returnType = getReturnType(type);
       if (callIdent in Functions.implementedFunctions) {
         // LLVM sometimes bitcasts for no reason. We must call using the exact same type as the actual function is generated as
-        var trueType = Functions.getSignatureReturnType(Functions.implementedFunctions[callIdent]);
+        var trueType = Functions.getSignatureType(Functions.implementedFunctions[callIdent][0]);
         if (trueType !== returnType && !isIdenticallyImplemented(trueType, returnType)) {
           if (VERBOSE) warnOnce('Fixing function call based on return type from signature, on ' + [callIdent, returnType, trueType]);
           returnType = trueType;
@@ -1628,7 +1619,11 @@ function JSify(data, functionsOnly, givenFunctions) {
 
     var ret = callIdent + '(' + args.join(',') + ')';
     if (ASM_JS) { // TODO: do only when needed (library functions and Math.*?) XXX && simpleIdent in Functions.libraryFunctions) {
-      ret = asmCoercion(ret, returnType);
+      if (ffiCall) {
+        ret = asmFFICoercion(ret, returnType);
+      } else {
+        ret = asmCoercion(ret, returnType);
+      }
       if (simpleIdent == 'abort' && funcData.returnType != 'void') {
         ret += '; return ' + asmCoercion('0', funcData.returnType); // special case: abort() can happen without return, breaking the return type of asm functions. ensure a return
       }
diff --git a/src/library.js b/src/library.js
index ccf62b27..b25e48ed 100644
--- a/src/library.js
+++ b/src/library.js
@@ -847,10 +847,7 @@ LibraryManager.library = {
       ___setErrNo(ERRNO_CODES.ERANGE);
       return 0;
     } else {
-      for (var i = 0; i < cwd.length; i++) {
-        {{{ makeSetValue('buf', 'i', 'cwd.charCodeAt(i)', 'i8') }}}
-      }
-      {{{ makeSetValue('buf', 'i', '0', 'i8') }}}
+      writeAsciiToMemory(cwd, buf);
       return buf;
     }
   },
@@ -1293,10 +1290,7 @@ LibraryManager.library = {
     if (namesize < ret.length + 1) {
       return ___setErrNo(ERRNO_CODES.ERANGE);
     } else {
-      for (var i = 0; i < ret.length; i++) {
-        {{{ makeSetValue('name', 'i', 'ret.charCodeAt(i)', 'i8') }}}
-      }
-      {{{ makeSetValue('name', 'i', '0', 'i8') }}}
+      writeAsciiToMemory(ret, name);
       return 0;
     }
   },
@@ -2699,10 +2693,7 @@ LibraryManager.library = {
     var result = dir + '/' + name;
     if (!_tmpnam.buffer) _tmpnam.buffer = _malloc(256);
     if (!s) s = _tmpnam.buffer;
-    for (var i = 0; i < result.length; i++) {
-      {{{ makeSetValue('s', 'i', 'result.charCodeAt(i)', 'i8') }}};
-    }
-    {{{ makeSetValue('s', 'i', '0', 'i8') }}};
+    writeAsciiToMemory(result, s);
     return s;
   },
   tempnam__deps: ['tmpnam'],
@@ -3343,10 +3334,7 @@ LibraryManager.library = {
     var ptrSize = {{{ Runtime.getNativeTypeSize('i8*') }}};
     for (var i = 0; i < strings.length; i++) {
       var line = strings[i];
-      for (var j = 0; j < line.length; j++) {
-        {{{ makeSetValue('poolPtr', 'j', 'line.charCodeAt(j)', 'i8') }}};
-      }
-      {{{ makeSetValue('poolPtr', 'j', '0', 'i8') }}};
+      writeAsciiToMemory(line, poolPtr);
       {{{ makeSetValue('envPtr', 'i * ptrSize', 'poolPtr', 'i8*') }}};
       poolPtr += line.length + 1;
     }
@@ -3976,10 +3964,7 @@ LibraryManager.library = {
         return ___setErrNo(ERRNO_CODES.ERANGE);
       } else {
         var msg = ERRNO_MESSAGES[errnum];
-        for (var i = 0; i < msg.length; i++) {
-          {{{ makeSetValue('strerrbuf', 'i', 'msg.charCodeAt(i)', 'i8') }}}
-        }
-        {{{ makeSetValue('strerrbuf', 'i', 0, 'i8') }}}
+        writeAsciiToMemory(msg, strerrbuf);
         return 0;
       }
     } else {
@@ -5067,10 +5052,7 @@ LibraryManager.library = {
     var layout = {{{ JSON.stringify(C_STRUCTS.utsname) }}};
     function copyString(element, value) {
       var offset = layout[element];
-      for (var i = 0; i < value.length; i++) {
-        {{{ makeSetValue('name', 'offset + i', 'value.charCodeAt(i)', 'i8') }}}
-      }
-      {{{ makeSetValue('name', 'offset + i', '0', 'i8') }}}
+      writeAsciiToMemory(value, name + offset);
     }
     if (name === 0) {
       return -1;
@@ -6131,8 +6113,10 @@ LibraryManager.library = {
     // int nanosleep(const struct timespec  *rqtp, struct timespec *rmtp);
     var seconds = {{{ makeGetValue('rqtp', C_STRUCTS.timespec.tv_sec, 'i32') }}};
     var nanoseconds = {{{ makeGetValue('rqtp', C_STRUCTS.timespec.tv_nsec, 'i32') }}};
-    {{{ makeSetValue('rmtp', C_STRUCTS.timespec.tv_sec, '0', 'i32') }}}
-    {{{ makeSetValue('rmtp', C_STRUCTS.timespec.tv_nsec, '0', 'i32') }}}
+    if (rmtp !== 0) {
+      {{{ makeSetValue('rmtp', C_STRUCTS.timespec.tv_sec, '0', 'i32') }}}
+      {{{ makeSetValue('rmtp', C_STRUCTS.timespec.tv_nsec, '0', 'i32') }}}
+    }
     return _usleep((seconds * 1e6) + (nanoseconds / 1000));
   },
   // TODO: Implement these for real.
@@ -6572,10 +6556,7 @@ LibraryManager.library = {
 
     var me = _nl_langinfo;
     if (!me.ret) me.ret = _malloc(32);
-    for (var i = 0; i < result.length; i++) {
-      {{{ makeSetValue('me.ret', 'i', 'result.charCodeAt(i)', 'i8') }}}
-    }
-    {{{ makeSetValue('me.ret', 'i', '0', 'i8') }}}
+    writeAsciiToMemory(result, me.ret);
     return me.ret;
   },
 
diff --git a/src/library_gl.js b/src/library_gl.js
index ecb72f0f..4b6ea579 100644
--- a/src/library_gl.js
+++ b/src/library_gl.js
@@ -530,7 +530,11 @@ var LibraryGL = {
         ret = allocate(intArrayFromString('OpenGL ES GLSL 1.00 (WebGL)'), 'i8', ALLOC_NORMAL);
         break;
       default:
-        throw 'Failure: Invalid glGetString value: ' + name_;
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetString: Unknown parameter ' + name_ + '!');
+#endif
+        return 0;
     }
     GL.stringCache[name_] = ret;
     return ret;
@@ -561,7 +565,11 @@ var LibraryGL = {
         {{{ makeSetValue('p', '0', 'result ? 1 : 0', 'i8') }}};
         break;
       case "string":
-        throw 'Native code calling glGetIntegerv(' + name_ + ') on a name which returns a string!';
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetIntegerv: Native code calling glGetIntegerv(' + name_ + ') on a name which returns a string!');
+#endif
+        return;
       case "object":
         if (result === null) {
           {{{ makeSetValue('p', '0', '0', 'i32') }}};
@@ -583,13 +591,19 @@ var LibraryGL = {
         } else if (result instanceof WebGLTexture) {
           {{{ makeSetValue('p', '0', 'result.name | 0', 'i32') }}};
         } else {
-          throw 'Unknown object returned from WebGL getParameter';
+          GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+          Module.printErr('GL_INVALID_ENUM in glGetIntegerv: Unknown object returned from WebGL getParameter(' + name_ + ')!');
+#endif
+          return;
         }
         break;
-      case "undefined":
-        throw 'Native code calling glGetIntegerv(' + name_ + ') and it returns undefined';
       default:
-        throw 'Why did we hit the default case?';
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetIntegerv: Native code calling glGetIntegerv(' + name_ + ') and it returns ' + result + ' of type ' + typeof(result) + '!');
+#endif
+        return;
     }
   },
 
@@ -607,7 +621,11 @@ var LibraryGL = {
           {{{ makeSetValue('p', '0', '0', 'float') }}};
       case "object":
         if (result === null) {
-          throw 'Native code calling glGetFloatv(' + name_ + ') and it returns null';
+          GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+          Module.printErr('GL_INVALID_ENUM in glGetFloatv: Native code calling glGetFloatv(' + name_ + ') and it returns null!');
+#endif
+          return;
         } else if (result instanceof Float32Array ||
                    result instanceof Uint32Array ||
                    result instanceof Int32Array ||
@@ -626,13 +644,19 @@ var LibraryGL = {
         } else if (result instanceof WebGLTexture) {
           {{{ makeSetValue('p', '0', 'result.name | 0', 'float') }}};
         } else {
-          throw 'Unknown object returned from WebGL getParameter';
+          GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+          Module.printErr('GL_INVALID_ENUM in glGetFloatv: Native code calling glGetFloatv(' + name_ + ') and it returns ' + result + ' of type ' + typeof(result) + '!');
+#endif
+          return;
         }
         break;
-      case "undefined":
-        throw 'Native code calling glGetFloatv(' + name_ + ') and it returns undefined';
       default:
-        throw 'Why did we hit the default case?';
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetFloatv: Native code calling glGetFloatv(' + name_ + ') and it returns ' + result + ' of type ' + typeof(result) + '!');
+#endif
+        return;
     }
   },
 
@@ -647,7 +671,11 @@ var LibraryGL = {
         {{{ makeSetValue('p', '0', 'result != 0', 'i8') }}};
         break;
       case "string":
-        throw 'Native code calling glGetBooleanv(' + name_ + ') on a name which returns a string!';
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetBooleanv: Native code calling glGetBooleanv(' + name_ + ') on a name which returns a string!');
+#endif
+        return;
       case "object":
         if (result === null) {
           {{{ makeSetValue('p', '0', '0', 'i8') }}};
@@ -665,13 +693,19 @@ var LibraryGL = {
                    result instanceof WebGLTexture) {
           {{{ makeSetValue('p', '0', '1', 'i8') }}}; // non-zero ID is always 1!
         } else {
-          throw 'Unknown object returned from WebGL getParameter';
+          GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+          Module.printErr('GL_INVALID_ENUM in glGetBooleanv: Unknown object returned from WebGL getParameter(' + name_ + ')!');
+#endif
+          return;
         }
         break;
-      case "undefined":
-          throw 'Unknown object returned from WebGL getParameter';
       default:
-        throw 'Why did we hit the default case?';
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetBooleanv: Native code calling glGetBooleanv(' + name_ + ') and it returns ' + result + ' of type ' + typeof(result) + '!');
+#endif
+        return;
     }
   },
 
@@ -759,7 +793,12 @@ var LibraryGL = {
       case 0x1908 /* GL_RGBA */:
         sizePerPixel = 4;
         break;
-      default: throw 'unsupported glReadPixels format';
+      default: 
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glReadPixels: Unsupported format ' + format + '!');
+#endif
+        return;
     }
     var totalSize = width*height*sizePerPixel;
     Module.ctx.readPixels(x, y, width, height, format, type, HEAPU8.subarray(pixels, pixels + totalSize));
@@ -2191,7 +2230,12 @@ var LibraryGL = {
         attribute = GLImmediate.clientAttributes[GLImmediate.COLOR]; break;
       case 0x8092: // GL_TEXTURE_COORD_ARRAY_POINTER
         attribute = GLImmediate.clientAttributes[GLImmediate.TEXTURE0 + GLImmediate.clientActiveTexture]; break;
-      default: throw 'TODO: glGetPointerv for ' + name;
+      default:
+        GL.recordError(0x0500/*GL_INVALID_ENUM*/);
+#if GL_ASSERTIONS
+        Module.printErr('GL_INVALID_ENUM in glGetPointerv: Unsupported name ' + name + '!');
+#endif
+        return;
     }
     {{{ makeSetValue('p', '0', 'attribute ? attribute.pointer : 0', 'i32') }}};
   },
diff --git a/src/library_sdl.js b/src/library_sdl.js
index 5b43b7ab..c46364ff 100644
--- a/src/library_sdl.js
+++ b/src/library_sdl.js
@@ -75,6 +75,7 @@ var LibrarySDL = {
     textInput: false,
 
     startTime: null,
+    initFlags: 0, // The flags passed to SDL_Init
     buttonState: 0,
     modState: 0,
     DOMButtons: [0, 0, 0],
@@ -639,6 +640,21 @@ var LibrarySDL = {
           {{{ makeSetValue('ptr', C_STRUCTS.SDL_ResizeEvent.h, 'event.h', 'i32') }}};
           break;
         }
+        case 'joystick_button_up': case 'joystick_button_down': {
+          var state = event.type === 'joystick_button_up' ? 0 : 1;
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyButtonEvent.type, 'SDL.DOMEventToSDLEvent[event.type]', 'i32') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyButtonEvent.which, 'event.index', 'i8') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyButtonEvent.button, 'event.button', 'i8') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyButtonEvent.state, 'state', 'i8') }}};
+          break;
+        }
+        case 'joystick_axis_motion': {
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyAxisEvent.type, 'SDL.DOMEventToSDLEvent[event.type]', 'i32') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyAxisEvent.which, 'event.index', 'i8') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyAxisEvent.axis, 'event.axis', 'i8') }}};
+          {{{ makeSetValue('ptr', C_STRUCTS.SDL_JoyAxisEvent.value, 'SDL.joystickAxisValueConversion(event.value)', 'i32') }}};
+          break;
+        }
         default: throw 'Unhandled SDL event: ' + event.type;
       }
     },
@@ -695,7 +711,109 @@ var LibrarySDL = {
       for (var i = 0; i < num; i++) {
         console.log('   diagonal ' + i + ':' + [data[i*surfData.width*4 + i*4 + 0], data[i*surfData.width*4 + i*4 + 1], data[i*surfData.width*4 + i*4 + 2], data[i*surfData.width*4 + i*4 + 3]]);
       }
-    }
+    },
+
+    // Joystick helper methods and state
+
+    joystickEventState: 0,
+    lastJoystickState: {}, // Map from SDL_Joystick* to their last known state. Required to determine if a change has occurred.
+    // Maps Joystick names to pointers. Allows us to avoid reallocating memory for
+    // joystick names each time this function is called.
+    joystickNamePool: {},
+    recordJoystickState: function(joystick, state) {
+      // Standardize button state.
+      var buttons = new Array(state.buttons.length);
+      for (var i = 0; i < state.buttons.length; i++) {
+        buttons[i] = SDL.getJoystickButtonState(state.buttons[i]);
+      }
+
+      SDL.lastJoystickState[joystick] = {
+        buttons: buttons,
+        axes: state.axes.slice(0),
+        timestamp: state.timestamp,
+        index: state.index,
+        id: state.id
+      };
+    },
+    // Retrieves the button state of the given gamepad button.
+    // Abstracts away implementation differences.
+    // Returns 'true' if pressed, 'false' otherwise.
+    getJoystickButtonState: function(button) {
+      if (typeof button === 'object') {
+        // Current gamepad API editor's draft (Firefox Nightly)
+        // https://dvcs.w3.org/hg/gamepad/raw-file/default/gamepad.html#idl-def-GamepadButton
+        return button.pressed;
+      } else {
+        // Current gamepad API working draft (Firefox / Chrome Stable)
+        // http://www.w3.org/TR/2012/WD-gamepad-20120529/#gamepad-interface
+        return button > 0;
+      }
+    },
+    // Queries for and inserts controller events into the SDL queue.
+    queryJoysticks: function() {
+      for (var joystick in SDL.lastJoystickState) {
+        var state = SDL.getGamepad(joystick - 1);
+        var prevState = SDL.lastJoystickState[joystick];
+        // Check only if the timestamp has differed.
+        // NOTE: Timestamp is not available in Firefox.
+        if (typeof state.timestamp !== 'number' || state.timestamp !== prevState.timestamp) {
+          var i;
+          for (i = 0; i < state.buttons.length; i++) {
+            var buttonState = SDL.getJoystickButtonState(state.buttons[i]);
+            // NOTE: The previous state already has a boolean representation of
+            //       its button, so no need to standardize its button state here.
+            if (buttonState !== prevState.buttons[i]) {
+              // Insert button-press event.
+              SDL.events.push({
+                type: buttonState ? 'joystick_button_down' : 'joystick_button_up',
+                joystick: joystick,
+                index: joystick - 1,
+                button: i
+              });
+            }
+          }
+          for (i = 0; i < state.axes.length; i++) {
+            if (state.axes[i] !== prevState.axes[i]) {
+              // Insert axes-change event.
+              SDL.events.push({
+                type: 'joystick_axis_motion',
+                joystick: joystick,
+                index: joystick - 1,
+                axis: i,
+                value: state.axes[i]
+              });
+            }
+          }
+
+          SDL.recordJoystickState(joystick, state);
+        }
+      }
+    },
+    // Converts the double-based browser axis value [-1, 1] into SDL's 16-bit
+    // value [-32768, 32767]
+    joystickAxisValueConversion: function(value) {
+      // Ensures that 0 is 0, 1 is 32767, and -1 is 32768.
+      return Math.ceil(((value+1) * 32767.5) - 32768);
+    },
+
+    getGamepads: function() {
+      var fcn = navigator.getGamepads || navigator.webkitGamepads || navigator.mozGamepads || navigator.gamepads || navigator.webkitGetGamepads;
+      if (fcn !== undefined) {
+        // The function must be applied on the navigator object.
+        return fcn.apply(navigator);
+      } else {
+        return [];
+      }
+    },
+
+    // Helper function: Returns the gamepad if available, or null if not.
+    getGamepad: function(deviceIndex) {
+      var gamepads = SDL.getGamepads();
+      if (gamepads.length > deviceIndex && deviceIndex >= 0) {
+        return gamepads[deviceIndex];
+      }
+      return null;
+    },
   },
 
   SDL_Linked_Version: function() {
@@ -708,8 +826,10 @@ var LibrarySDL = {
     return SDL.version;
   },
 
-  SDL_Init: function(what) {
+  SDL_Init: function(initFlags) {
     SDL.startTime = Date.now();
+    SDL.initFlags = initFlags;
+
     // capture all key events. we just keep down and up, but also capture press to prevent default actions
     if (!Module['doNotCaptureKeyboard']) {
       document.addEventListener("keydown", SDL.receiveEvent);
@@ -718,6 +838,15 @@ var LibrarySDL = {
       window.addEventListener("blur", SDL.receiveEvent);
       document.addEventListener("visibilitychange", SDL.receiveEvent);
     }
+
+    if (initFlags & 0x200) {
+      // SDL_INIT_JOYSTICK
+      // Firefox will not give us Joystick data unless we register this NOP
+      // callback.
+      // https://bugzilla.mozilla.org/show_bug.cgi?id=936104
+      addEventListener("gamepadconnected", function() {});
+    }
+
     window.addEventListener("unload", SDL.receiveEvent);
     SDL.keyboardState = _malloc(0x10000); // Our SDL needs 512, but 64K is safe for older SDLs
     _memset(SDL.keyboardState, 0, 0x10000);
@@ -730,6 +859,12 @@ var LibrarySDL = {
     SDL.DOMEventToSDLEvent['mousemove'] = 0x400 /* SDL_MOUSEMOTION */;
     SDL.DOMEventToSDLEvent['unload'] = 0x100 /* SDL_QUIT */;
     SDL.DOMEventToSDLEvent['resize'] = 0x7001 /* SDL_VIDEORESIZE/SDL_EVENT_COMPAT2 */;
+    // These are not technically DOM events; the HTML gamepad API is poll-based.
+    // However, we define them here, as the rest of the SDL code assumes that
+    // all SDL events originate as DOM events.
+    SDL.DOMEventToSDLEvent['joystick_axis_motion'] = 0x600 /* SDL_JOYAXISMOTION */;
+    SDL.DOMEventToSDLEvent['joystick_button_down'] = 0x603 /* SDL_JOYBUTTONDOWN */;
+    SDL.DOMEventToSDLEvent['joystick_button_up'] = 0x604 /* SDL_JOYBUTTONUP */;
     return 0; // success
   },
 
@@ -1189,6 +1324,11 @@ var LibrarySDL = {
   },
 
   SDL_PollEvent: function(ptr) {
+    if (SDL.initFlags & 0x200 && SDL.joystickEventState) {
+      // If SDL_INIT_JOYSTICK was supplied AND the joystick system is configured
+      // to automatically query for events, query for joystick events.
+      SDL.queryJoysticks();
+    }
     if (SDL.events.length === 0) return 0;
     if (ptr) {
       SDL.makeCEvent(SDL.events.shift(), ptr);
@@ -2375,37 +2515,103 @@ var LibrarySDL = {
 
   // Joysticks
 
-  SDL_NumJoysticks: function() { return 0; },
+  SDL_NumJoysticks: function() {
+    var count = 0;
+    var gamepads = SDL.getGamepads();
+    // The length is not the number of gamepads; check which ones are defined.
+    for (var i = 0; i < gamepads.length; i++) {
+      if (gamepads[i] !== undefined) count++;
+    }
+    return count;
+  },
 
-  SDL_JoystickName: function(deviceIndex) { return 0; },
+  SDL_JoystickName: function(deviceIndex) {
+    var gamepad = SDL.getGamepad(deviceIndex);
+    if (gamepad) {
+      var name = gamepad.id;
+      if (SDL.joystickNamePool.hasOwnProperty(name)) {
+        return SDL.joystickNamePool[name];
+      }
+      return SDL.joystickNamePool[name] = allocate(intArrayFromString(name), 'i8', ALLOC_NORMAL);
+    }
+    return 0;
+  },
 
-  SDL_JoystickOpen: function(deviceIndex) { return 0; },
+  SDL_JoystickOpen: function(deviceIndex) {
+    var gamepad = SDL.getGamepad(deviceIndex);
+    if (gamepad) {
+      // Use this as a unique 'pointer' for this joystick.
+      var joystick = deviceIndex+1;
+      SDL.recordJoystickState(joystick, gamepad);