diff --git a/ispc.vcxproj b/ispc.vcxproj
index 36fbad5d..74186ac0 100755
--- a/ispc.vcxproj
+++ b/ispc.vcxproj
@@ -53,8 +53,10 @@
     <ClCompile Include="$(Configuration)\gen-bitcode-sse4-64bit.cpp" />
     <ClCompile Include="$(Configuration)\gen-bitcode-sse4-x2-32bit.cpp" />
     <ClCompile Include="$(Configuration)\gen-bitcode-sse4-x2-64bit.cpp" />
-    <ClCompile Include="$(Configuration)\gen-stdlib-generic.cpp" />
-    <ClCompile Include="$(Configuration)\gen-stdlib-x86.cpp" />
+    <ClCompile Include="$(Configuration)\gen-stdlib-mask1.cpp" />
+    <ClCompile Include="$(Configuration)\gen-stdlib-mask8.cpp" />
+    <ClCompile Include="$(Configuration)\gen-stdlib-mask16.cpp" />
+    <ClCompile Include="$(Configuration)\gen-stdlib-mask32.cpp" />
     <ClCompile Include="ispc.cpp" />
     <ClCompile Include="$(Configuration)\lex.cc">
       <DisableSpecificWarnings>4146;4800;4996;4355;4624;4005;4003;4018</DisableSpecificWarnings>
@@ -97,11 +99,13 @@
   <ItemGroup>
     <CustomBuild Include="stdlib.ispc">
       <FileType>Document</FileType>
-      <Command>%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC=1 -DPI=3.1415926535 | python stdlib2cpp.py x86 &gt; $(Configuration)/gen-stdlib-x86.cpp;
-%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC=1 -DISPC_TARGET_GENERIC=1 -DPI=3.1415926535 | python stdlib2cpp.py generic &gt; $(Configuration)/gen-stdlib-generic.cpp;
+      <Command>%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC_MASK_BITS=1 -DISPC=1 -DPI=3.1415926535 | python stdlib2cpp.py mask1 &gt; $(Configuration)/gen-stdlib-mask1.cpp;
+%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC_MASK_BITS=8 -DISPC=1 -DPI=3.1415926535 | python stdlib2cpp.py mask8 &gt; $(Configuration)/gen-stdlib-mask8.cpp;
+%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC_MASK_BITS=16 -DISPC=1 -DPI=3.1415926535 | python stdlib2cpp.py mask16 &gt; $(Configuration)/gen-stdlib-mask16.cpp;
+%LLVM_INSTALL_DIR%\bin\clang -E -x c %(Filename).ispc -DISPC_MASK_BITS=32 -DISPC=1 -DPI=3.1415926535 | python stdlib2cpp.py mask32 &gt; $(Configuration)/gen-stdlib-mask32.cpp;
 </Command>
-      <Outputs>$(Configuration)/gen-stdlib-generic.cpp;$(Configuration)/gen-stdlib-x86.cpp</Outputs>
-      <Message>Building gen-stdlib-{generic,x86}.cpp</Message>
+      <Outputs>$(Configuration)/gen-stdlib-mask1.cpp;$(Configuration)/gen-stdlib-mask8.cpp;$(Configuration)/gen-stdlib-mask16.cpp;$(Configuration)/gen-stdlib-mask32.cpp</Outputs>
+      <Message>Building gen-stdlib-{mask1,8,16,32}.cpp</Message>
     </CustomBuild>
   </ItemGroup>
   <ItemGroup>