diff --git a/engine/l_studio.cpp b/engine/l_studio.cpp
index 9855e1a00..b49077d6a 100644
--- a/engine/l_studio.cpp
+++ b/engine/l_studio.cpp
@@ -40,7 +40,7 @@
 #include "materialsystem/materialsystem_config.h"
 #include "materialsystem/itexture.h"
 #include "IHammer.h"
-#if defined( _WIN32 ) && !defined( _X360 ) && !defined(_M_ARM)
+#if defined( _WIN32 ) && defined( _M_IX86 )
 #include <xmmintrin.h>
 #endif
 #include "staticpropmgr.h"
diff --git a/public/materialsystem/imesh.h b/public/materialsystem/imesh.h
index 19cd83e1b..a6d5e92bc 100644
--- a/public/materialsystem/imesh.h
+++ b/public/materialsystem/imesh.h
@@ -1220,7 +1220,7 @@ inline void CVertexBuilder::FastVertexSSE( const ModelVertexDX7_t &vertex )
 	Assert( m_CompressionType == VERTEX_COMPRESSION_NONE ); // FIXME: support compressed verts if needed
 	Assert( m_nCurrentVertex < m_nMaxVertexCount );
 
-#if defined( _WIN32 ) && !defined( _X360 ) && defined( _M_IX86 )
+#if defined( _WIN32 ) && defined( _M_IX86 )
 	const void *pRead = &vertex;
 	void *pCurrPos = m_pCurrPosition;
 	__asm
@@ -1265,7 +1265,7 @@ inline void CVertexBuilder::Fast4VerticesSSE(
 	Assert( m_CompressionType == VERTEX_COMPRESSION_NONE ); // FIXME: support compressed verts if needed
 	Assert( m_nCurrentVertex < m_nMaxVertexCount-3 );
 
-#if defined( _WIN32 ) && !defined( _X360 ) && defined( _M_IX86 )
+#if defined( _WIN32 ) && defined( _M_IX86 )
 	void *pCurrPos = m_pCurrPosition;
 	__asm
 	{
@@ -1426,7 +1426,7 @@ inline void CVertexBuilder::FastVertexSSE( const ModelVertexDX8_t &vertex )
 	Assert( m_CompressionType == VERTEX_COMPRESSION_NONE ); // FIXME: support compressed verts if needed
 	Assert( m_nCurrentVertex < m_nMaxVertexCount );
 
-#if defined( _WIN32 ) && !defined( _X360 ) && defined( _M_IX86 )
+#if defined( _WIN32 ) && defined( _M_IX86 )
 	const void *pRead = &vertex;
 	void *pCurrPos = m_pCurrPosition;
 	__asm
diff --git a/public/mathlib/mathlib.h b/public/mathlib/mathlib.h
index 4be9e8c9c..aeb4aedef 100644
--- a/public/mathlib/mathlib.h
+++ b/public/mathlib/mathlib.h
@@ -1188,7 +1188,7 @@ inline float SimpleSplineRemapValClamped( float val, float A, float B, float C,
 
 FORCEINLINE int RoundFloatToInt(float f)
 {
-#if defined(__i386__) || defined(_M_IX86) || defined(__x86_64__)
+#if defined(__i386__) || defined(__x86_64__) || defined(_M_IX86) || defined(PLATFORM_WINDOWS_PC64)
 	return _mm_cvtss_si32(_mm_load_ss(&f));
 #elif defined( _X360 )
 #ifdef Assert
diff --git a/public/mathlib/ssemath.h b/public/mathlib/ssemath.h
index 8b0c11581..91525ba67 100644
--- a/public/mathlib/ssemath.h
+++ b/public/mathlib/ssemath.h
@@ -1834,7 +1834,7 @@ FORCEINLINE fltx4 ReplicateX4( float flValue )
 FORCEINLINE float SubFloat( const fltx4 & a, int idx )
 {
 	// NOTE: if the output goes into a register, this causes a Load-Hit-Store stall (don't mix fpu/vpu math!)
-#if defined(_WIN32) && defined(__i386__) || defined(__x86_64__)
+#if defined(_WIN32) && (defined(__i386__) || defined(__x86_64__))
 	return a.m128_f32[ idx ];
 #else
 	return (reinterpret_cast<float const *>(&a))[idx];
@@ -1843,7 +1843,7 @@ FORCEINLINE float SubFloat( const fltx4 & a, int idx )
 
 FORCEINLINE float & SubFloat( fltx4 & a, int idx )
 {
-#if defined(_WIN32) && defined(__i386__) || defined(__x86_64__)
+#if defined(_WIN32) && (defined(__i386__) || defined(__x86_64__))
 	return a.m128_f32[ idx ];
 #else
 	return (reinterpret_cast<float *>(&a))[idx];
@@ -1857,7 +1857,7 @@ FORCEINLINE uint32 SubFloatConvertToInt( const fltx4 & a, int idx )
 
 FORCEINLINE uint32 SubInt( const fltx4 & a, int idx )
 {
-#if defined(_WIN32) && defined(__i386__) || defined(__x86_64__)
+#if defined(_WIN32) && (defined(__i386__) || defined(__x86_64__))
 	return a.m128_u32[ idx ];
 #else
 	return (reinterpret_cast<uint32 const *>(&a))[idx];
@@ -1866,7 +1866,7 @@ FORCEINLINE uint32 SubInt( const fltx4 & a, int idx )
 
 FORCEINLINE uint32 & SubInt( fltx4 & a, int idx )
 {
-#if defined(_WIN32) && defined(__i386__) || defined(__x86_64__)
+#if defined(_WIN32) && (defined(__i386__) || defined(__x86_64__))
 	return a.m128_u32[ idx ];
 #else
 	return (reinterpret_cast<uint32 *>(&a))[idx];
diff --git a/public/tier0/tslist.h b/public/tier0/tslist.h
index 90aec6482..5e05639f0 100644
--- a/public/tier0/tslist.h
+++ b/public/tier0/tslist.h
@@ -37,7 +37,6 @@
 #if defined( PLATFORM_64BITS ) && !defined(_M_ARM64)
 
 #if defined (PLATFORM_WINDOWS) 
-typedef __int128 int128;
 //typedef __m128i int128;
 //inline int128 int128_zero()	{ return _mm_setzero_si128(); }
 #else  // PLATFORM_WINDOWS
diff --git a/studiorender/r_studiodraw.cpp b/studiorender/r_studiodraw.cpp
index c39b43263..9c6b1ecbc 100644
--- a/studiorender/r_studiodraw.cpp
+++ b/studiorender/r_studiodraw.cpp
@@ -657,7 +657,7 @@ static matrix3x4_t *ComputeSkinMatrix( mstudioboneweight_t &boneweights, matrix3
 static matrix3x4_t *ComputeSkinMatrixSSE( mstudioboneweight_t &boneweights, matrix3x4_t *pPoseToWorld, matrix3x4_t &result )
 {
 	// NOTE: pPoseToWorld, being cache aligned, doesn't need explicit initialization
-#if defined( _WIN32 ) && !defined( _X360 ) && defined(_M_IX86)
+#if defined( _WIN32 ) && defined(_M_IX86)
 	switch( boneweights.numbones )
 	{
 	default:
diff --git a/tier0/cpu.cpp b/tier0/cpu.cpp
index 92467c0d2..10efb38d4 100644
--- a/tier0/cpu.cpp
+++ b/tier0/cpu.cpp
@@ -22,7 +22,7 @@ const tchar* GetProcessorVendorId();
 
 static bool cpuid(uint32 function, uint32& out_eax, uint32& out_ebx, uint32& out_ecx, uint32& out_edx)
 {
-#if !defined(__i386__) && !defined(__x86_64) || defined( _X360 )
+#if !defined(__i386__) && !defined(__x86_64)
 	return false;
 #elif defined(GNUC)
 
diff --git a/tier0/stacktools.cpp b/tier0/stacktools.cpp
index c458135ed..f804c452a 100644
--- a/tier0/stacktools.cpp
+++ b/tier0/stacktools.cpp
@@ -175,7 +175,7 @@ int GetCallStack_Fast( void **pReturnAddressesOut, int iArrayCount, int iSkipCou
 {
 	//Only tested in windows. This function won't work with frame pointer omission enabled. "vpc /nofpo" all projects
 #if (defined( TIER0_FPO_DISABLED ) || defined( _DEBUG )) &&\
-	(defined( WIN32 ) && !defined( _X360 ) && defined(_M_X86))
+	(defined( WIN32 ) && defined(_M_X86))
 	void *pStackCrawlEBP;
 	__asm
 	{
@@ -1467,7 +1467,7 @@ CStackTop_CopyParentStack::CStackTop_CopyParentStack( void * const *pParentStack
 #if defined( ENABLE_RUNTIME_STACK_TRANSLATION )
 	//miniature version of GetCallStack_Fast()
 #if (defined( TIER0_FPO_DISABLED ) || defined( _DEBUG )) &&\
-	(defined( WIN32 ) && !defined( _X360 ) && defined(_M_X86))
+	(defined( WIN32 ) && defined(_M_X86))
 	void *pStackCrawlEBP;
 	__asm
 	{
@@ -1525,7 +1525,7 @@ CStackTop_ReferenceParentStack::CStackTop_ReferenceParentStack( void * const *pP
 #if defined( ENABLE_RUNTIME_STACK_TRANSLATION )
 	//miniature version of GetCallStack_Fast()
 #if (defined( TIER0_FPO_DISABLED ) || defined( _DEBUG )) &&\
-	(defined( WIN32 ) && !defined( _X360 ) && defined(_M_X86))
+	(defined( WIN32 ) && defined(_M_X86))
 	void *pStackCrawlEBP;
 	__asm
 	{