diff --git a/premake5.lua b/premake5.lua
index 836e6d94b..052cce492 100644
--- a/premake5.lua
+++ b/premake5.lua
@@ -7,7 +7,7 @@ objdir(build_obj)
 
 -- Define an ARCH variable
 -- Only use this to enable architecture-specific functionality.
-if os.is("linux") then
+if os.istarget("linux") then
   ARCH = os.outputof("uname -p")
 else
   ARCH = "unknown"
@@ -221,9 +221,9 @@ solution("xenia")
   uuid("931ef4b0-6170-4f7a-aaf2-0fece7632747")
   startproject("xenia-app")
   architecture("x86_64")
-  if os.is("linux") then
+  if os.istarget("linux") then
     platforms({"Linux"})
-  elseif os.is("windows") then
+  elseif os.istarget("windows") then
     platforms({"Windows"})
     -- Minimum version to support ID3D12GraphicsCommandList1 (for
     -- SetSamplePositions).
@@ -266,7 +266,7 @@ solution("xenia")
   include("src/xenia/ui/vulkan")
   include("src/xenia/vfs")
 
-  if os.is("windows") then
+  if os.istarget("windows") then
     include("src/xenia/apu/xaudio2")
     include("src/xenia/gpu/d3d12")
     include("src/xenia/hid/winkey")
diff --git a/src/xenia/app/premake5.lua b/src/xenia/app/premake5.lua
index 0c371d6bf..40db69f08 100644
--- a/src/xenia/app/premake5.lua
+++ b/src/xenia/app/premake5.lua
@@ -40,9 +40,6 @@ project("xenia-app")
     "xenia-vfs",
     "xxhash",
   })
-  flags({
-    "WinMain",  -- Use WinMain instead of main.
-  })
   defines({
     "XBYAK_NO_OP_NAMES",
     "XBYAK_ENABLE_OMITTED_OPERAND",
diff --git a/src/xenia/cpu/backend/x64/x64_backend.cc b/src/xenia/cpu/backend/x64/x64_backend.cc
index 4e6356959..28a530759 100644
--- a/src/xenia/cpu/backend/x64/x64_backend.cc
+++ b/src/xenia/cpu/backend/x64/x64_backend.cc
@@ -497,22 +497,22 @@ void X64ThunkEmitter::EmitSaveVolatileRegs() {
   mov(qword[rsp + offsetof(StackLayout::Thunk, r[5])], r10);
   mov(qword[rsp + offsetof(StackLayout::Thunk, r[6])], r11);
 
-  // movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[0])], xmm0);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[1])], xmm1);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[2])], xmm2);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[3])], xmm3);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[4])], xmm4);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[5])], xmm5);
+  // vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[0])], xmm0);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[1])], xmm1);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[2])], xmm2);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[3])], xmm3);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[4])], xmm4);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[5])], xmm5);
 }
 
 void X64ThunkEmitter::EmitLoadVolatileRegs() {
   // Load volatile registers from our stack frame.
-  // movaps(xmm0, qword[rsp + offsetof(StackLayout::Thunk, xmm[0])]);
-  movaps(xmm1, qword[rsp + offsetof(StackLayout::Thunk, xmm[1])]);
-  movaps(xmm2, qword[rsp + offsetof(StackLayout::Thunk, xmm[2])]);
-  movaps(xmm3, qword[rsp + offsetof(StackLayout::Thunk, xmm[3])]);
-  movaps(xmm4, qword[rsp + offsetof(StackLayout::Thunk, xmm[4])]);
-  movaps(xmm5, qword[rsp + offsetof(StackLayout::Thunk, xmm[5])]);
+  // vmovaps(xmm0, qword[rsp + offsetof(StackLayout::Thunk, xmm[0])]);
+  vmovaps(xmm1, qword[rsp + offsetof(StackLayout::Thunk, xmm[1])]);
+  vmovaps(xmm2, qword[rsp + offsetof(StackLayout::Thunk, xmm[2])]);
+  vmovaps(xmm3, qword[rsp + offsetof(StackLayout::Thunk, xmm[3])]);
+  vmovaps(xmm4, qword[rsp + offsetof(StackLayout::Thunk, xmm[4])]);
+  vmovaps(xmm5, qword[rsp + offsetof(StackLayout::Thunk, xmm[5])]);
 
   // mov(rax, qword[rsp + offsetof(StackLayout::Thunk, r[0])]);
   mov(rcx, qword[rsp + offsetof(StackLayout::Thunk, r[1])]);
@@ -535,29 +535,29 @@ void X64ThunkEmitter::EmitSaveNonvolatileRegs() {
   mov(qword[rsp + offsetof(StackLayout::Thunk, r[7])], r14);
   mov(qword[rsp + offsetof(StackLayout::Thunk, r[8])], r15);
 
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[0])], xmm6);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[1])], xmm7);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[2])], xmm8);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[3])], xmm9);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[4])], xmm10);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[5])], xmm11);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[6])], xmm12);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[7])], xmm13);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[8])], xmm14);
-  movaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[9])], xmm15);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[0])], xmm6);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[1])], xmm7);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[2])], xmm8);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[3])], xmm9);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[4])], xmm10);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[5])], xmm11);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[6])], xmm12);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[7])], xmm13);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[8])], xmm14);
+  vmovaps(qword[rsp + offsetof(StackLayout::Thunk, xmm[9])], xmm15);
 }
 
 void X64ThunkEmitter::EmitLoadNonvolatileRegs() {
-  movaps(xmm6, qword[rsp + offsetof(StackLayout::Thunk, xmm[0])]);
-  movaps(xmm7, qword[rsp + offsetof(StackLayout::Thunk, xmm[1])]);
-  movaps(xmm8, qword[rsp + offsetof(StackLayout::Thunk, xmm[2])]);
-  movaps(xmm9, qword[rsp + offsetof(StackLayout::Thunk, xmm[3])]);
-  movaps(xmm10, qword[rsp + offsetof(StackLayout::Thunk, xmm[4])]);
-  movaps(xmm11, qword[rsp + offsetof(StackLayout::Thunk, xmm[5])]);
-  movaps(xmm12, qword[rsp + offsetof(StackLayout::Thunk, xmm[6])]);
-  movaps(xmm13, qword[rsp + offsetof(StackLayout::Thunk, xmm[7])]);
-  movaps(xmm14, qword[rsp + offsetof(StackLayout::Thunk, xmm[8])]);
-  movaps(xmm15, qword[rsp + offsetof(StackLayout::Thunk, xmm[9])]);
+  vmovaps(xmm6, qword[rsp + offsetof(StackLayout::Thunk, xmm[0])]);
+  vmovaps(xmm7, qword[rsp + offsetof(StackLayout::Thunk, xmm[1])]);
+  vmovaps(xmm8, qword[rsp + offsetof(StackLayout::Thunk, xmm[2])]);
+  vmovaps(xmm9, qword[rsp + offsetof(StackLayout::Thunk, xmm[3])]);
+  vmovaps(xmm10, qword[rsp + offsetof(StackLayout::Thunk, xmm[4])]);
+  vmovaps(xmm11, qword[rsp + offsetof(StackLayout::Thunk, xmm[5])]);
+  vmovaps(xmm12, qword[rsp + offsetof(StackLayout::Thunk, xmm[6])]);
+  vmovaps(xmm13, qword[rsp + offsetof(StackLayout::Thunk, xmm[7])]);
+  vmovaps(xmm14, qword[rsp + offsetof(StackLayout::Thunk, xmm[8])]);
+  vmovaps(xmm15, qword[rsp + offsetof(StackLayout::Thunk, xmm[9])]);
 
   mov(rbx, qword[rsp + offsetof(StackLayout::Thunk, r[0])]);
   mov(rcx, qword[rsp + offsetof(StackLayout::Thunk, r[1])]);
diff --git a/src/xenia/gpu/vulkan/premake5.lua b/src/xenia/gpu/vulkan/premake5.lua
index f8e9903fe..6a7b9200b 100644
--- a/src/xenia/gpu/vulkan/premake5.lua
+++ b/src/xenia/gpu/vulkan/premake5.lua
@@ -59,9 +59,6 @@ project("xenia-gpu-vulkan-trace-viewer")
     "xenia-vfs",
     "xxhash",
   })
-  flags({
-    "WinMain",  -- Use WinMain instead of main.
-  })
   defines({
   })
   includedirs({
diff --git a/src/xenia/hid/premake5.lua b/src/xenia/hid/premake5.lua
index 1b374a4fb..ea7b6afbf 100644
--- a/src/xenia/hid/premake5.lua
+++ b/src/xenia/hid/premake5.lua
@@ -33,9 +33,6 @@ project("xenia-hid-demo")
     "xenia-ui",
     "xenia-ui-vulkan",
   })
-  flags({
-    "WinMain",  -- Use WinMain instead of main.
-  })
   defines({
     "GLEW_STATIC=1",
     "GLEW_MX=1",
diff --git a/src/xenia/ui/vulkan/premake5.lua b/src/xenia/ui/vulkan/premake5.lua
index e9abb1c5c..8246ef249 100644
--- a/src/xenia/ui/vulkan/premake5.lua
+++ b/src/xenia/ui/vulkan/premake5.lua
@@ -37,9 +37,6 @@ project("xenia-ui-window-vulkan-demo")
     "xenia-ui-spirv",
     "xenia-ui-vulkan",
   })
-  flags({
-    "WinMain",  -- Use WinMain instead of main.
-  })
   defines({
   })
   includedirs({
diff --git a/src/xenia/vfs/premake5.lua b/src/xenia/vfs/premake5.lua
index be71cef59..ea174e3e0 100644
--- a/src/xenia/vfs/premake5.lua
+++ b/src/xenia/vfs/premake5.lua
@@ -26,9 +26,6 @@ project("xenia-vfs-dump")
     "xenia-base",
     "xenia-vfs",
   })
-  flags({
-    -- "WinMain",  -- Use WinMain instead of main.
-  })
   defines({})
   includedirs({
     project_root.."/third_party/gflags/src",
diff --git a/third_party/premake-core b/third_party/premake-core
index 61d799c8f..8593bc948 160000
--- a/third_party/premake-core
+++ b/third_party/premake-core
@@ -1 +1 @@
-Subproject commit 61d799c8f9d1ab8130942b2d9dcd2819b9d8b049
+Subproject commit 8593bc9480924f0d0724a4533e8de70222e6a08d
diff --git a/third_party/vswhere/vswhere.exe b/third_party/vswhere/vswhere.exe
index 80706d852..096d016fb 100644
Binary files a/third_party/vswhere/vswhere.exe and b/third_party/vswhere/vswhere.exe differ
diff --git a/tools/build/bin/premake5.exe b/tools/build/bin/premake5.exe
index bcf844443..ed8857680 100644
Binary files a/tools/build/bin/premake5.exe and b/tools/build/bin/premake5.exe differ
diff --git a/tools/build/premake b/tools/build/premake
index aa6ae27ad..c4c471d99 100644
--- a/tools/build/premake
+++ b/tools/build/premake
@@ -69,9 +69,8 @@ def build_premake():
     elif sys.platform == 'win32':
       # Grab Visual Studio version and execute shell to set up environment.
       vs_version = import_vs_environment()
-      if vs_version != 2015:
-        print('ERROR: Visual Studio 2015 not found!')
-        print('Ensure you have the VS140COMNTOOLS environment variable!')
+      if vs_version is None:
+        print('ERROR: Visual Studio not found!')
         sys.exit(1)
         return
 
@@ -143,17 +142,30 @@ def import_vs_environment():
     A version such as 2015 or None if no VS is found.
   """
   version = 0
+
+  candidate_path = subprocess.check_output('../../third_party/vswhere/vswhere.exe -all -version "[15,)" -latest -format value -property installationPath', shell=False, universal_newlines=True)
+  candidate_path = candidate_path.strip()
+
   tools_path = ''
-  if 'VS140COMNTOOLS' in os.environ:
+  if candidate_path:
+    tools_path = os.path.join(candidate_path, 'vc\\auxiliary\\build\\vcvarsall.bat')
+    if os.path.isfile(tools_path) and os.access(tools_path, os.X_OK):
+      version = subprocess.check_output('../../third_party/vswhere/vswhere.exe -version "[15,)" -latest -format value -property catalog_productLineVersion', shell=False, universal_newlines=True)
+      version = version.strip()
+      if version:
+        version = int(version)
+      else:
+        version = 2017
+  if version == 0 and 'VS140COMNTOOLS' in os.environ:
     version = 2015
     tools_path = os.environ['VS140COMNTOOLS']
+    tools_path = os.path.join(tools_path, '..\\..\\vc\\vcvarsall.bat')
   if version == 0:
     return None
-  tools_path = os.path.join(tools_path, '..\\..\\vc\\vcvarsall.bat')
 
-  args = [tools_path, '&&', 'set']
+  args = [tools_path, 'x64', '&&', 'set']
   popen = subprocess.Popen(
-      args, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+      args, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=True)
   variables, _ = popen.communicate()
   envvars_to_save = (
       'devenvdir',
diff --git a/tools/build/premake5.lua b/tools/build/premake5.lua
index 49575613f..6a66f5a2b 100644
--- a/tools/build/premake5.lua
+++ b/tools/build/premake5.lua
@@ -1,3 +1,5 @@
+require("vstudio")
+
 include("scripts/build_paths.lua")
 include("scripts/force_compile_as_c.lua")
 include("scripts/force_compile_as_cc.lua")
diff --git a/tools/build/scripts/build_paths.lua b/tools/build/scripts/build_paths.lua
index 5fcceb061..e97bac0f4 100644
--- a/tools/build/scripts/build_paths.lua
+++ b/tools/build/scripts/build_paths.lua
@@ -7,7 +7,7 @@ build_tools = "tools/build"
 build_scripts = build_tools .. "/scripts"
 build_tools_src = build_tools .. "/src"
 
-if os.is("windows") then
+if os.istarget("windows") then
   platform_suffix = "win"
 else
   platform_suffix = "posix"
diff --git a/tools/build/scripts/force_compile_as_c.lua b/tools/build/scripts/force_compile_as_c.lua
index e26c3b7ec..30de988e9 100644
--- a/tools/build/scripts/force_compile_as_c.lua
+++ b/tools/build/scripts/force_compile_as_c.lua
@@ -21,7 +21,11 @@ if premake.override then
   -- for msvc
   premake.override(premake.vstudio.vc2010, "additionalCompileOptions", function(base, cfg, condition)
     if cfg.abspath and table.contains(forced_c_files, cfg.abspath) then
-      _p(3,'<CompileAs %s>CompileAsC</CompileAs>', condition)
+      if condition == nil or condition == '' then
+        _p(3,'<CompileAs>CompileAsC</CompileAs>')
+      else
+        _p(3,'<CompileAs Condition="\'$(Configuration)|$(Platform)\'==\'%s\'">CompileAsC</CompileAs>', condition)
+      end
     end
     return base(cfg, condition)
   end)
diff --git a/tools/build/scripts/force_compile_as_cc.lua b/tools/build/scripts/force_compile_as_cc.lua
index 16c680476..c7a15cef0 100644
--- a/tools/build/scripts/force_compile_as_cc.lua
+++ b/tools/build/scripts/force_compile_as_cc.lua
@@ -21,7 +21,11 @@ if premake.override then
   -- for msvc
   premake.override(premake.vstudio.vc2010, "additionalCompileOptions", function(base, cfg, condition)
     if cfg.abspath and table.contains(forced_cc_files, cfg.abspath) then
-      _p(3,'<CompileAs %s>CompileAsCpp</CompileAs>', condition)
+      if condition == nil or condition == '' then
+        _p(3,'<CompileAs>CompileAsCpp</CompileAs>')
+      else
+        _p(3,'<CompileAs Condition="\'$(Configuration)|$(Platform)\'==\'%s\'">CompileAsCpp</CompileAs>', condition)
+      end
     end
     return base(cfg, condition)
   end)
diff --git a/xenia-build b/xenia-build
index b6cf45401..0e7c27d2b 100755
--- a/xenia-build
+++ b/xenia-build
@@ -100,7 +100,12 @@ def import_vs_environment():
     if candidate_path:
         tools_path = os.path.join(candidate_path, 'vc\\auxiliary\\build\\vcvarsall.bat')
         if os.path.isfile(tools_path) and os.access(tools_path, os.X_OK):
-            version = 2017
+            version = subprocess.check_output('third_party/vswhere/vswhere.exe -version "[15,)" -latest -format value -property catalog_productLineVersion', shell=False, universal_newlines=True)
+            version = version.strip()
+            if version:
+                version = int(version)
+            else:
+                version = 2017
     if version == 0 and 'VS140COMNTOOLS' in os.environ:
         version = 2015
         tools_path = os.environ['VS140COMNTOOLS']
@@ -317,16 +322,19 @@ def run_premake(target_os, action, cc=None):
       target_os: target --os to pass to premake.
       action: action to preform.
     """
-    ret = subprocess.call([
+    args = [
         sys.executable,
         os.path.join('tools', 'build', 'premake'),
         '--file=premake5.lua',
         '--os=%s' % target_os,
-        '--cc=%s' % ('clang' if not cc else cc),
         '--test-suite-mode=combined',
         '--verbose',
         action,
-        ], shell=False)
+    ]
+    if cc:
+        args.insert(4, '--cc=%s' % cc)
+
+    ret = subprocess.call(args, shell=False)
 
     if ret == 0:
         generate_version_h()