From d449e35e2db08980721dcce968cc65808fe4c534 Mon Sep 17 00:00:00 2001
From: myT <mighty.cow@mailinator.com>
Date: Sat, 31 Dec 2016 02:16:36 +0100
Subject: [PATCH] simplified the code implementing Sys_GetProcessorId (and
 removed the inline asm)

---
 code/win32/win_shared.cpp | 113 ++++++--------------------------------
 1 file changed, 18 insertions(+), 95 deletions(-)

diff --git a/code/win32/win_shared.cpp b/code/win32/win_shared.cpp
index 36ade30..6a4d076 100644
--- a/code/win32/win_shared.cpp
+++ b/code/win32/win_shared.cpp
@@ -23,6 +23,7 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 #include "../qcommon/q_shared.h"
 #include "../qcommon/qcommon.h"
 #include "win_local.h"
+#include <intrin.h>
 
 
 int Sys_Milliseconds()
@@ -36,134 +37,56 @@ int Sys_Milliseconds()
 }
 
 
-// disable all optimizations temporarily so this code works correctly!
-#ifdef _MSC_VER
-#pragma optimize( "", off )
-#pragma warning(disable : 4748) // don't fkn WHINE about using that pragma
-#endif
-
-
-static void CPUID( int func, unsigned regs[4] )
-{
-	unsigned regEAX, regEBX, regECX, regEDX;
-
-	__asm mov eax, func
-	__asm __emit 00fh
-	__asm __emit 0a2h
-	__asm mov regEAX, eax
-	__asm mov regEBX, ebx
-	__asm mov regECX, ecx
-	__asm mov regEDX, edx
-
-	regs[0] = regEAX;
-	regs[1] = regEBX;
-	regs[2] = regECX;
-	regs[3] = regEDX;
-}
-
-static qbool IsPentium()
-{
-	__asm
-	{
-		pushfd						// save eflags
-		pop		eax
-		test	eax, 0x00200000		// check ID bit
-		jz		set21				// bit 21 is not set, so jump to set_21
-		and		eax, 0xffdfffff		// clear bit 21
-		push	eax					// save new value in register
-		popfd						// store new value in flags
-		pushfd
-		pop		eax
-		test	eax, 0x00200000		// check ID bit
-		jz		good
-		jmp		err					// cpuid not supported
-set21:
-		or		eax, 0x00200000		// set ID bit
-		push	eax					// store new value
-		popfd						// store new value in EFLAGS
-		pushfd
-		pop		eax
-		test	eax, 0x00200000		// if bit 21 is on
-		jnz		good
-		jmp		err
-	}
-
-err:
-	return qfalse;
-good:
-	return qtrue;
-}
-
 static const char* CPU_Name()
 {
-	static unsigned regs[4];
-
-	CPUID( 0, regs );
+	static int regs[4];
 
+	__cpuid( regs, 0 );
 	regs[0] = regs[1];
 	regs[1] = regs[3];
 	regs[3] = 0;
+
 	return (const char*)regs;
 }
 
-static int CPU_Cores()
-{
-	unsigned regs[4];
-	CPUID( 1, regs );
-	return ((regs[1] & 0x00FF0000) >> 16);
-}
 
 struct CPU_FeatureBit { const char* s; int reg, bit; } CPU_FeatureBits[] =
 {
+#if id386 // x64 always has those anyway
 	{ " MMX",  3, 23 },
 	{ " SSE",  3, 25 },
 	{ " SSE2", 3, 26 },
-	{ " SSE3", 2, 26 },
-	{ 0 }
+#endif
+	{ " SSE3", 2, 0 },
+	{ " SSSE3", 2, 9 },
+	{ " SSE4.1", 2, 19 },
+	{ " SSE4.2", 2, 20 },
+	{ " AVX", 2, 28 }
+	// for AVX2 and later, you'd need to call cpuid with eax=7 and ecx=0 ("extended features")
 };
+static const int CPU_FeatureBitCount = sizeof(CPU_FeatureBits) / sizeof(CPU_FeatureBits[0]);
 
 
 int Sys_GetProcessorId()
 {
-#if defined _M_ALPHA
-	return CPUID_AXP;
-#elif !defined _M_IX86
-	return CPUID_GENERIC;
-#else
-
-	// verify we're at least a Pentium or 486 w/ CPUID support
-	if ( !IsPentium() ) {
-		Cvar_Set( "sys_cpustring", "x86 (pre-Pentium)" );
-		return CPUID_UNSUPPORTED;
-	}
-
-	char s[64] = "";
+	char s[256] = "";
 	Q_strcat( s, sizeof(s), CPU_Name() );
 
-	if (CPU_Cores() > 1)
-		Q_strcat( s, sizeof(s), va(" %d cores", CPU_Cores()) );
+	int regs[4];
+	__cpuid( regs, 1 );
 
-	unsigned regs[4];
-	CPUID( 1, regs );
-
-	for (int i = 0; CPU_FeatureBits[i].s; ++i) {
+	for (int i = 0; i < CPU_FeatureBitCount; ++i) {
 		if (regs[CPU_FeatureBits[i].reg] & (1 << regs[CPU_FeatureBits[i].bit])) {
 			Q_strcat( s, sizeof(s), CPU_FeatureBits[i].s );
 		}
 	}
 
 	Cvar_Set( "sys_cpustring", s );
+
 	return CPUID_GENERIC;
-
-#endif
 }
 
 
-#ifdef _MSC_VER
-#pragma optimize( "", on )
-#endif
-
-
 const char* Sys_GetCurrentUser()
 {
 	return "player";