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__cpuid, __cpuidex

Microsoft Specific

Generates the cpuid instruction that is available on x86 and x64. This instruction queries the processor for information about the supported features and CPU type.

void __cpuid(
   int CPUInfo[4],
   int InfoType
);

void __cpuidex(
   int CPUInfo[4],
   int InfoType,
   int ECXValue
);

Parameters

  • [out] CPUInfo
    An array of four integers that contains the gathered information about supported features and the CPU.

  • [in] InfoType
    A code that indicates what information this instruction retrieves.

  • [in] ECXValue
    The value of the ECX register before this intrinsic generates the cpuid instruction.

Requirements

Intrinsic

Architecture

__cpuid

x86, x64

__cpuidex

x86, x64

Header file <intrin.h>

Remarks

This instruction stores the supported features and CPU information in CPUInfo, an array of four 32-bit integers that is filled with the values of the EAX, EBX, ECX, and EDX registers (in that order) after you call the cpuid instruction. The information has a different meaning depending on the value passed as the InfoType parameter. The information returned with various values of InfoType is processor-dependent.

The __cpuidex intrinsic sets the value of the ECX register before it generates the cpuid instruction. This enables you to gather additional information about the processor.

When the InfoType argument is 0, the following table describes the output.

Information Returned

Array index

Bit range

Description

0

0-31

Maximum value for the InfoType parameter that will return valid information.

1

0-31

Identification string (part 1)

2

0-31

Identification string (part 3)

3

0-31

Identification string (part 2)

When the InfoType argument is 1, the following table describes the output.

CPU Information Returned

Array index

Bit range

Description

0

0-3

Stepping ID

0

4-7

Model

0

8-11

Family

0

12-13

Processor type (Intel)

Reserved (AMD)

0

14-15

Reserved

0

16-19

Extended model

0

20-27

Extended family

0

28-31

Reserved

1

0-7

Brand index

1

8-15

The size of the CLFLUSH cache line, in quadwords

1

16-23

Logical processor count

1

24-31

Initial APIC ID

2

0

SSE3 new instructions

2

1-2

Reserved

2

3

MONITOR/MWAIT

2

4

CPL Qualified Debug Store (Intel)

Reserved (AMD)

2

5

Virtual machine extensions (Intel)

Reserved (AMD)

2

6

Safer mode extensions (Intel)

Reserved (AMD)

2

7

Enhanced Intel SpeedStep technology (Intel)

Reserved (AMD)

2

8

Thermal Monitor (Intel)

Reserved (AMD)2

2

9

Supplemental Streaming SIMD Extensions 3 (SSSE3)

2

10

L1 context ID (Intel)

Reserved (AMD)

2

11

Reserved

2

12

256-bit FMA extensions (Intel)

Reserved (AMD)

2

13

CMPXCHG16B support

2

14

xTPR update control

2

15

Perf/Debug capability MSR

2

16-17

Reserved

2

18

Direct cache access (DCA) support (Intel)

Reserved (AMD)

2

19

SSE4.1 extensions

2

20

SSE4.2 extensions

2

21

x2APIC support (Intel)

Reserved (AMD)

2

22

MOVBE support (Intel)

Reserved (AMD)

2

23

POPCNT instruction support

2

24

Reserved

2

25

AES support (Intel)

Reserved (AMD)

2

26

XSAVE support (Intel)

Reserved (AMD)

2

27

OSXSAVE support (Intel)

Reserved (AMD)

2

28

256-bit Intel advanced vector extensions (Intel)

Reserved (AMD)

2

29-31

Reserved

3

0-31

Feature information (see later in the topic)

The following table shows the meaning of the feature information value, the value of EDX which is written to CPUInfo[3], when the InfoType argument is 1.

Feature Information Returned

Bit

Mnemonic

Description

0

FPU

x87 FPU on chip

1

VME

Virtual-8086 mode enhancement

2

DE

Debugging extensions

3

PSE

Page size extensions

4

TSC

Time stamp counter

5

MSR

RDMSR and WRMSR support

6

PAE

Physical address extensions

7

MCE

Machine check exception

8

CX8

CMPXCHG8B instruction

9

APIC

APIC on chip

10

n/a

Reserved

11

SEP

SYSENTER and SYSEXIT

12

MTRR

Memory type range registers

13

PGE

PTE global bit

14

MCA

Machine check architecture

15

CMOV

Conditional move/compare instruction

16

PAT

Page Attribute Table

17

PSE-36

36-bit page size extension

18

PSN

Processor serial number

19

CLFSH

CFLUSH instruction

20

n/a

Reserved

21

DS

Debug store

22

ACPI

Thermal monitor and clock control

23

MMX

MMX technology

24

FXSR

FXSAVE/FXRSTOR

25

SSE

SSE extensions

26

SSE2

SSE2 extensions

27

SS

Self snoop

28

HTT

Multithreading

29

TM

Thermal monitor

30

n/a

Reserved

31

PBE

Pending break enable

Note

With the AMD chipset, all multi-core AMD CPUs set bit 28 of the feature information bits to indicate that the chip has more than one core. This is the case even though AMD does not support hyper-threading.

Some processors, such as the SSE3 and SSE4-enabled processors, support additional InfoType values. When the InfoType argument is 2, this instruction returns cache information in encoded forms.

The following table shows the values this instruction returns when you set InfoType to 4. This is cache information is related to one of the cache levels. To retrieve this information, you must set the ECX register. Use the __cpuidex intrinsic to set ECX to the zero-based index for the cache level to query.

Deterministic Cache Information

Array Index

Bit Range

Description

0

0-4

Cache type field

0

5-7

Cache level

0

8

Self-initializing cache

0

9

Fully associative cache

0

10-13

Reserved

0

14-25

Maximum number of threads

0

26-31

Maximum number of IDs for processor cores

1

0-11

System coherency line size

1

12-21

Physical line partitions

1

22-31

Ways of associativity

2

0-31

Number of sets

3

0-31

Reserved

When InfoType is 5, these processors return information about the monitor feature (see _mm_monitor).

When InfoType is 6, processors return information about the digital temperature and power management.

When InfoType is 0x0A, these processers return information obtained by monitoring the architectural performance.

Some processors support Extended Function CPUID information. If this is supported, InfoType values from 0x80000000 might be used to return information. To determine the maximum meaningful value allowed, set InfoType to 0x80000000. The maximum value of InfoType supported will be written to CPUInfo[0]. The following table shows values returned using the extended function CPUID information.

Extended Function CPUID Information

InfoType

Array index

Bit range

Information

0x80000000

0

0-31

Maximum meaningful value of InfoType for extended function CPUID information.

0x80000000

1-3

0-31

Reserved.

0x80000001

0

0-31

Extended processor signature and extended feature bits

0x80000001

1

0-31

Reserved

0x80000001

2

0

LAHF/SAHF available in 64-bit mode

0x80000001

2

1

Core multi-processing legacy mode (CmpLegacy) (AMD)

Reserved (Intel)

0x80000001

2

2

Secure virtual machine (SVM) (AMD)

Reserved (Intel)

0x80000001

2

3

Extended APIC Register Space (ExtApicSpace) (AMD)

Reserved (Intel)

0x80000001

2

4

AltMovCr8 (AMD)

Reserved (Intel)

0x80000001

2

5

LZCNT Support (AMD)

Reserved (Intel)

0x80000001

2

6

SSE4A instruction support (EXTRQ, INSERTQ, MOVNTSD, MOVNTSS) (AMD)

Reserved (Intel)

0x80000001

2

7

Misaligned SSE support mode available (AMD)

Reserved (Intel)

0x80000001

2

8

PREFETCH and PREFETCHW support (AMD)

Reserved (Intel)

0x80000001

2

9-11

Reserved

0x80000001

2

12

SKINIT and DEV support (AMD)

Reserved (Intel)

0x80000001

2

13-31

Reserved

0x80000001

3

0-10

Reserved

0x80000001

3

11

SYSCALL/SYSRET available in 64-bit mode

0x80000001

3

12-19

Reserved

0x80000001

3

20

Execute disable bit available

0x80000001

3

21

Reserved

0x80000001

3

22

Extensions to MMX instructions (AMD)

Reserved (Intel)

0x80000001

3

23-24

Reserved

0x80000001

3

25

FFXSR (AMD)

Reserved (Intel)

0x80000001

3

26

1GB page support (AMD)

Reserved (Intel)

0x80000001

3

27

RDTSCP support (AMD)

Reserved (Intel)

0x80000001

3

28

Reserved

0x80000001

3

29

64-bit technology available

0x80000001

3

30

3DnowExt (AMD)

Reserved (Intel)

0x80000001

3

31

3Dnow! instructions (AMD)

Reserved (Intel)

0x80000002

0-3

0-31

Processor brand string

0x80000003

0-3

0-31

Processor brand string, continued

0x80000004

0-3

0-31

Processor brand string, continued

0x80000005

0-3

0-31

L1 cache and TLB identifiers (AMD)

Reserved (Intel)

0x80000006

0-1

0-31

Reserved

0x80000006

2

0-7

Cache line size

0x80000006

2

8-11

Reserved

0x80000006

2

12-15

L2 associativity

0x80000006

2

16-31

Cache size in 1K units

0x80000006

3

0-31

Reserved

0x80000007

0-3

0-31

Advanced power management information (AMD)

Reserved (Intel)

0x80000008

0

0-7

Physical address bits

0x80000008

0

8-15

Virtual address bits

0x80000008

0

16-31

Reserved

0x80000008

1-3

0-31

Reserved

0x8000000A

0

0-7

SVM revision (AMD)

Reserved (Intel)

0x8000000A

0

8-31

Reserved

0x8000000A

1

0-31

NASID - Number of Address Space Identifiers (AMD)

Reserved (Intel)

0x8000000A

2

0-31

Reserved

0x8000000A

3

0

Nested paging (AMD)

Reserved (Intel)

0x8000000A

3

1

LBR visualization (AMD)

Reserved (Intel)

0x8000000A

3

2-31

Reserved

0x80000019

0-3

0-31

TLB 1GB page identifiers (AMD)

Reserved (Intel)

0x8000001A

0

0

FP128 optimization (AMD)

Reserved (Intel)

0x8000001A

0

1

MOVU, MOVUPS, MOVUPD optimization over MOVL/MOVH, MOVHLPS/MOVHPS, MOVLPD/MOVHPD (AMD)

Reserved (Intel)

0x8000001A

0

2-31

Reserved

0x8000001A

1-3

0-31

Reserved

Example

// cpuid.cpp 
// processor: x86, x64
// Use the __cpuid intrinsic to get information about a CPU

#include <stdio.h>
#include <string.h>
#include <intrin.h>

const char* szFeatures[] =
{
    "x87 FPU On Chip",
    "Virtual-8086 Mode Enhancement",
    "Debugging Extensions",
    "Page Size Extensions",
    "Time Stamp Counter",
    "RDMSR and WRMSR Support",
    "Physical Address Extensions",
    "Machine Check Exception",
    "CMPXCHG8B Instruction",
    "APIC On Chip",
    "Unknown1",
    "SYSENTER and SYSEXIT",
    "Memory Type Range Registers",
    "PTE Global Bit",
    "Machine Check Architecture",
    "Conditional Move/Compare Instruction",
    "Page Attribute Table",
    "36-bit Page Size Extension",
    "Processor Serial Number",
    "CFLUSH Extension",
    "Unknown2",
    "Debug Store",
    "Thermal Monitor and Clock Ctrl",
    "MMX Technology",
    "FXSAVE/FXRSTOR",
    "SSE Extensions",
    "SSE2 Extensions",
    "Self Snoop",
    "Multithreading Technology",
    "Thermal Monitor",
    "Unknown4",
    "Pending Break Enable"
};

int main(int argc, char* argv[])
{
    char CPUString[0x20];
    char CPUBrandString[0x40];
    int CPUInfo[4] = {-1};
    int nSteppingID = 0;
    int nModel = 0;
    int nFamily = 0;
    int nProcessorType = 0;
    int nExtendedmodel = 0;
    int nExtendedfamily = 0;
    int nBrandIndex = 0;
    int nCLFLUSHcachelinesize = 0;
    int nLogicalProcessors = 0;
    int nAPICPhysicalID = 0;
    int nFeatureInfo = 0;
    int nCacheLineSize = 0;
    int nL2Associativity = 0;
    int nCacheSizeK = 0;
    int nPhysicalAddress = 0;
    int nVirtualAddress = 0;
    int nRet = 0;

    int nCores = 0;
    int nCacheType = 0;
    int nCacheLevel = 0;
    int nMaxThread = 0;
    int nSysLineSize = 0;
    int nPhysicalLinePartitions = 0;
    int nWaysAssociativity = 0;
    int nNumberSets = 0;

    unsigned    nIds, nExIds, i;

    bool    bSSE3Instructions = false;
    bool    bMONITOR_MWAIT = false;
    bool    bCPLQualifiedDebugStore = false;
    bool    bVirtualMachineExtensions = false;
    bool    bEnhancedIntelSpeedStepTechnology = false;
    bool    bThermalMonitor2 = false;
    bool    bSupplementalSSE3 = false;
    bool    bL1ContextID = false;
    bool    bCMPXCHG16B = false;
    bool    bxTPRUpdateControl = false;
    bool    bPerfDebugCapabilityMSR = false;
    bool    bSSE41Extensions = false;
    bool    bSSE42Extensions = false;
    bool    bPOPCNT = false;

    bool    bMultithreading = false;

    bool    bLAHF_SAHFAvailable = false;
    bool    bCmpLegacy = false;
    bool    bSVM = false;
    bool    bExtApicSpace = false;
    bool    bAltMovCr8 = false;
    bool    bLZCNT = false;
    bool    bSSE4A = false;
    bool    bMisalignedSSE = false;
    bool    bPREFETCH = false;
    bool    bSKINITandDEV = false;
    bool    bSYSCALL_SYSRETAvailable = false;
    bool    bExecuteDisableBitAvailable = false;
    bool    bMMXExtensions = false;
    bool    bFFXSR = false;
    bool    b1GBSupport = false;
    bool    bRDTSCP = false;
    bool    b64Available = false;
    bool    b3DNowExt = false;
    bool    b3DNow = false;
    bool    bNestedPaging = false;
    bool    bLBRVisualization = false;
    bool    bFP128 = false;
    bool    bMOVOptimization = false;

    bool    bSelfInit = false;
    bool    bFullyAssociative = false;

    // __cpuid with an InfoType argument of 0 returns the number of
    // valid Ids in CPUInfo[0] and the CPU identification string in
    // the other three array elements. The CPU identification string is
    // not in linear order. The code below arranges the information 
    // in a human readable form.
    __cpuid(CPUInfo, 0);
    nIds = CPUInfo[0];
    memset(CPUString, 0, sizeof(CPUString));
    *((int*)CPUString) = CPUInfo[1];
    *((int*)(CPUString+4)) = CPUInfo[3];
    *((int*)(CPUString+8)) = CPUInfo[2];

    // Get the information associated with each valid Id
    for (i=0; i<=nIds; ++i)
    {
        __cpuid(CPUInfo, i);
        printf_s("\nFor InfoType %d\n", i); 
        printf_s("CPUInfo[0] = 0x%x\n", CPUInfo[0]);
        printf_s("CPUInfo[1] = 0x%x\n", CPUInfo[1]);
        printf_s("CPUInfo[2] = 0x%x\n", CPUInfo[2]);
        printf_s("CPUInfo[3] = 0x%x\n", CPUInfo[3]);

        // Interpret CPU feature information.
        if  (i == 1)
        {
            nSteppingID = CPUInfo[0] & 0xf;
            nModel = (CPUInfo[0] >> 4) & 0xf;
            nFamily = (CPUInfo[0] >> 8) & 0xf;
            nProcessorType = (CPUInfo[0] >> 12) & 0x3;
            nExtendedmodel = (CPUInfo[0] >> 16) & 0xf;
            nExtendedfamily = (CPUInfo[0] >> 20) & 0xff;
            nBrandIndex = CPUInfo[1] & 0xff;
            nCLFLUSHcachelinesize = ((CPUInfo[1] >> 8) & 0xff) * 8;
            nLogicalProcessors = ((CPUInfo[1] >> 16) & 0xff);
            nAPICPhysicalID = (CPUInfo[1] >> 24) & 0xff;
            bSSE3Instructions = (CPUInfo[2] & 0x1) || false;
            bMONITOR_MWAIT = (CPUInfo[2] & 0x8) || false;
            bCPLQualifiedDebugStore = (CPUInfo[2] & 0x10) || false;
            bVirtualMachineExtensions = (CPUInfo[2] & 0x20) || false;
            bEnhancedIntelSpeedStepTechnology = (CPUInfo[2] & 0x80) || false;
            bThermalMonitor2 = (CPUInfo[2] & 0x100) || false;
            bSupplementalSSE3 = (CPUInfo[2] & 0x200) || false;
            bL1ContextID = (CPUInfo[2] & 0x300) || false;
            bCMPXCHG16B= (CPUInfo[2] & 0x2000) || false;
            bxTPRUpdateControl = (CPUInfo[2] & 0x4000) || false;
            bPerfDebugCapabilityMSR = (CPUInfo[2] & 0x8000) || false;
            bSSE41Extensions = (CPUInfo[2] & 0x80000) || false;
            bSSE42Extensions = (CPUInfo[2] & 0x100000) || false;
            bPOPCNT= (CPUInfo[2] & 0x800000) || false;
            nFeatureInfo = CPUInfo[3];
            bMultithreading = (nFeatureInfo & (1 << 28)) || false;
        }
    }

    // Calling __cpuid with 0x80000000 as the InfoType argument
    // gets the number of valid extended IDs.
    __cpuid(CPUInfo, 0x80000000);
    nExIds = CPUInfo[0];
    memset(CPUBrandString, 0, sizeof(CPUBrandString));

    // Get the information associated with each extended ID.
    for (i=0x80000000; i<=nExIds; ++i)
    {
        __cpuid(CPUInfo, i);
        printf_s("\nFor InfoType %x\n", i); 
        printf_s("CPUInfo[0] = 0x%x\n", CPUInfo[0]);
        printf_s("CPUInfo[1] = 0x%x\n", CPUInfo[1]);
        printf_s("CPUInfo[2] = 0x%x\n", CPUInfo[2]);
        printf_s("CPUInfo[3] = 0x%x\n", CPUInfo[3]);

        if  (i == 0x80000001)
        {
            bLAHF_SAHFAvailable = (CPUInfo[2] & 0x1) || false;
            bCmpLegacy = (CPUInfo[2] & 0x2) || false;
            bSVM = (CPUInfo[2] & 0x4) || false;
            bExtApicSpace = (CPUInfo[2] & 0x8) || false;
            bAltMovCr8 = (CPUInfo[2] & 0x10) || false;
            bLZCNT = (CPUInfo[2] & 0x20) || false;
            bSSE4A = (CPUInfo[2] & 0x40) || false;
            bMisalignedSSE = (CPUInfo[2] & 0x80) || false;
            bPREFETCH = (CPUInfo[2] & 0x100) || false;
            bSKINITandDEV = (CPUInfo[2] & 0x1000) || false;
            bSYSCALL_SYSRETAvailable = (CPUInfo[3] & 0x800) || false;
            bExecuteDisableBitAvailable = (CPUInfo[3] & 0x10000) || false;
            bMMXExtensions = (CPUInfo[3] & 0x40000) || false;
            bFFXSR = (CPUInfo[3] & 0x200000) || false;
            b1GBSupport = (CPUInfo[3] & 0x400000) || false;
            bRDTSCP = (CPUInfo[3] & 0x8000000) || false;
            b64Available = (CPUInfo[3] & 0x20000000) || false;
            b3DNowExt = (CPUInfo[3] & 0x40000000) || false;
            b3DNow = (CPUInfo[3] & 0x80000000) || false;
        }

        // Interpret CPU brand string and cache information.
        if  (i == 0x80000002)
            memcpy(CPUBrandString, CPUInfo, sizeof(CPUInfo));
        else if  (i == 0x80000003)
            memcpy(CPUBrandString + 16, CPUInfo, sizeof(CPUInfo));
        else if  (i == 0x80000004)
            memcpy(CPUBrandString + 32, CPUInfo, sizeof(CPUInfo));
        else if  (i == 0x80000006)
        {
            nCacheLineSize = CPUInfo[2] & 0xff;
            nL2Associativity = (CPUInfo[2] >> 12) & 0xf;
            nCacheSizeK = (CPUInfo[2] >> 16) & 0xffff;
        }
        else if  (i == 0x80000008)
        {
           nPhysicalAddress = CPUInfo[0] & 0xff;
           nVirtualAddress = (CPUInfo[0] >> 8) & 0xff;
        }
        else if  (i == 0x8000000A)
        {
            bNestedPaging = (CPUInfo[3] & 0x1) || false;
            bLBRVisualization = (CPUInfo[3] & 0x2) || false;
        }
        else if  (i == 0x8000001A)
        {
            bFP128 = (CPUInfo[0] & 0x1) || false;
            bMOVOptimization = (CPUInfo[0] & 0x2) || false;
        }
    }

    // Display all the information in user-friendly format.

    printf_s("\n\nCPU String: %s\n", CPUString);

    if  (nIds >= 1)
    {
        if  (nSteppingID)
            printf_s("Stepping ID = %d\n", nSteppingID);
        if  (nModel)
            printf_s("Model = %d\n", nModel);
        if  (nFamily)
            printf_s("Family = %d\n", nFamily);
        if  (nProcessorType)
            printf_s("Processor Type = %d\n", nProcessorType);
        if  (nExtendedmodel)
            printf_s("Extended model = %d\n", nExtendedmodel);
        if  (nExtendedfamily)
            printf_s("Extended family = %d\n", nExtendedfamily);
        if  (nBrandIndex)
            printf_s("Brand Index = %d\n", nBrandIndex);
        if  (nCLFLUSHcachelinesize)
            printf_s("CLFLUSH cache line size = %d\n",
                     nCLFLUSHcachelinesize);
        if (bMultithreading && (nLogicalProcessors > 0))
           printf_s("Logical Processor Count = %d\n", nLogicalProcessors);
        if  (nAPICPhysicalID)
            printf_s("APIC Physical ID = %d\n", nAPICPhysicalID);

        if  (nFeatureInfo || bSSE3Instructions ||
             bMONITOR_MWAIT || bCPLQualifiedDebugStore ||
             bVirtualMachineExtensions || bEnhancedIntelSpeedStepTechnology ||
             bThermalMonitor2 || bSupplementalSSE3 || bL1ContextID || 
             bCMPXCHG16B || bxTPRUpdateControl || bPerfDebugCapabilityMSR || 
             bSSE41Extensions || bSSE42Extensions || bPOPCNT || 
             bLAHF_SAHFAvailable || bCmpLegacy || bSVM ||
             bExtApicSpace || bAltMovCr8 ||
             bLZCNT || bSSE4A || bMisalignedSSE ||
             bPREFETCH || bSKINITandDEV || bSYSCALL_SYSRETAvailable || 
             bExecuteDisableBitAvailable || bMMXExtensions || bFFXSR || b1GBSupport ||
             bRDTSCP || b64Available || b3DNowExt || b3DNow || bNestedPaging || 
             bLBRVisualization || bFP128 || bMOVOptimization )
        {
            printf_s("\nThe following features are supported:\n");

            if  (bSSE3Instructions)
                printf_s("\tSSE3\n");
            if  (bMONITOR_MWAIT)
                printf_s("\tMONITOR/MWAIT\n");
            if  (bCPLQualifiedDebugStore)
                printf_s("\tCPL Qualified Debug Store\n");
            if  (bVirtualMachineExtensions)
                printf_s("\tVirtual Machine Extensions\n");
            if  (bEnhancedIntelSpeedStepTechnology)
                printf_s("\tEnhanced Intel SpeedStep Technology\n");
            if  (bThermalMonitor2)
                printf_s("\tThermal Monitor 2\n");
            if  (bSupplementalSSE3)
                printf_s("\tSupplemental Streaming SIMD Extensions 3\n");
            if  (bL1ContextID)
                printf_s("\tL1 Context ID\n");
            if  (bCMPXCHG16B)
                printf_s("\tCMPXCHG16B Instruction\n");
            if  (bxTPRUpdateControl)
                printf_s("\txTPR Update Control\n");
            if  (bPerfDebugCapabilityMSR)
                printf_s("\tPerf\\Debug Capability MSR\n");
            if  (bSSE41Extensions)
                printf_s("\tSSE4.1 Extensions\n");
            if  (bSSE42Extensions)
                printf_s("\tSSE4.2 Extensions\n");
            if  (bPOPCNT)
                printf_s("\tPPOPCNT Instruction\n");

            i = 0;
            nIds = 1;
            while (i < (sizeof(szFeatures)/sizeof(const char*)))
            {
                if  (nFeatureInfo & nIds)
                {
                    printf_s("\t");
                    printf_s(szFeatures[i]);
                    printf_s("\n");
                }

                nIds <<= 1;
                ++i;
            }
            if (bLAHF_SAHFAvailable)
                printf_s("\tLAHF/SAHF in 64-bit mode\n");
            if (bCmpLegacy)
                printf_s("\tCore multi-processing legacy mode\n");
            if (bSVM)
                printf_s("\tSecure Virtual Machine\n");
            if (bExtApicSpace)
                printf_s("\tExtended APIC Register Space\n");
            if (bAltMovCr8)
                printf_s("\tAltMovCr8\n");
            if (bLZCNT)
                printf_s("\tLZCNT instruction\n");
            if (bSSE4A)
                printf_s("\tSSE4A (EXTRQ, INSERTQ, MOVNTSD, MOVNTSS)\n");
            if (bMisalignedSSE)
                printf_s("\tMisaligned SSE mode\n");
            if (bPREFETCH)
                printf_s("\tPREFETCH and PREFETCHW Instructions\n");
            if (bSKINITandDEV)
                printf_s("\tSKINIT and DEV support\n");
            if (bSYSCALL_SYSRETAvailable)
                printf_s("\tSYSCALL/SYSRET in 64-bit mode\n");
            if (bExecuteDisableBitAvailable)
                printf_s("\tExecute Disable Bit\n");
            if (bMMXExtensions)
                printf_s("\tExtensions to MMX Instructions\n");
            if (bFFXSR)
                printf_s("\tFFXSR\n");
            if (b1GBSupport)
                printf_s("\t1GB page support\n");
            if (bRDTSCP)
                printf_s("\tRDTSCP instruction\n");
            if (b64Available)
                printf_s("\t64 bit Technology\n");
            if (b3DNowExt)
                printf_s("\t3Dnow Ext\n");
            if (b3DNow)
                printf_s("\t3Dnow! instructions\n");
            if (bNestedPaging)
                printf_s("\tNested Paging\n");
            if (bLBRVisualization)
                printf_s("\tLBR Visualization\n");
            if (bFP128)
                printf_s("\tFP128 optimization\n");
            if (bMOVOptimization)
                printf_s("\tMOVU Optimization\n");
        }
    }

    if  (nExIds >= 0x80000004)
        printf_s("\nCPU Brand String: %s\n", CPUBrandString);

    if  (nExIds >= 0x80000006)
    {
        printf_s("Cache Line Size = %d\n", nCacheLineSize);
        printf_s("L2 Associativity = %d\n", nL2Associativity);
        printf_s("Cache Size = %dK\n", nCacheSizeK);
    }


    for (i=0;;i+)
    {
        __cpuidex(CPUInfo, 0x4, i);
        if(!(CPUInfo[0] & 0xf0)) break;

        if(i == 0)
        {
            nCores = CPUInfo[0] >> 26;
            printf_s("\n\nNumber of Cores = %d\n", nCores + 1);
        }

        nCacheType = (CPUInfo[0] & 0x1f);
        nCacheLevel = (CPUInfo[0] & 0xe0) >> 5;
        bSelfInit = (CPUInfo[0] & 0x100) >> 8;
        bFullyAssociative = (CPUInfo[0] & 0x200) >> 9;
        nMaxThread = (CPUInfo[0] & 0x03ffc000) >> 14;
        nSysLineSize = (CPUInfo[1] & 0x0fff);
        nPhysicalLinePartitions = (CPUInfo[1] & 0x03ff000) >> 12;
        nWaysAssociativity = (CPUInfo[1]) >> 22;
        nNumberSets = CPUInfo[2];

        printf_s("\n");

        printf_s("ECX Index %d\n", i);
        switch (nCacheType)
        {
            case 0:
                printf_s("   Type: Null\n");
                break;
            case 1:
                printf_s("   Type: Data Cache\n");
                break;
            case 2:
                printf_s("   Type: Instruction Cache\n");
                break;
            case 3:
                printf_s("   Type: Unified Cache\n");
                break;
            default:
                 printf_s("   Type: Unknown\n");
        }

        printf_s("   Level = %d\n", nCacheLevel + 1); 
        if (bSelfInit)
        {
            printf_s("   Self Initializing\n");
        }
        else
        {
            printf_s("   Not Self Initializing\n");
        }
        if (bFullyAssociative)
        {
            printf_s("   Is Fully Associatve\n");
        }
        else
        {
            printf_s("   Is Not Fully Associatve\n");
        }
        printf_s("   Max Threads = %d\n", 
            nMaxThread+1);
        printf_s("   System Line Size = %d\n", 
            nSysLineSize+1);
        printf_s("   Physical Line Partions = %d\n", 
            nPhysicalLinePartitions+1);
        printf_s("   Ways of Associativity = %d\n", 
            nWaysAssociativity+1);
        printf_s("   Number of Sets = %d\n", 
            nNumberSets+1);
    }

    return  nRet;
}

For InfoType 0 CPUInfo[0] = 0x5 CPUInfo[1] = 0x756e6547 CPUInfo[2] = 0x6c65746e CPUInfo[3] = 0x49656e69 For InfoType 1 CPUInfo[0] = 0xf4a CPUInfo[1] = 0x1020800 CPUInfo[2] = 0x659d CPUInfo[3] = 0xbfebfbff For InfoType 2 CPUInfo[0] = 0x605b5001 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x7d7040 For InfoType 3 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 4 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 5 CPUInfo[0] = 0x40 CPUInfo[1] = 0x40 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 80000000 CPUInfo[0] = 0x80000008 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 80000001 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x1 CPUInfo[3] = 0x20100000 For InfoType 80000002 CPUInfo[0] = 0x20202020 CPUInfo[1] = 0x20202020 CPUInfo[2] = 0x20202020 CPUInfo[3] = 0x6e492020 For InfoType 80000003 CPUInfo[0] = 0x286c6574 CPUInfo[1] = 0x50202952 CPUInfo[2] = 0x69746e65 CPUInfo[3] = 0x52286d75 For InfoType 80000004 CPUInfo[0] = 0x20342029 CPUInfo[1] = 0x20555043 CPUInfo[2] = 0x30362e33 CPUInfo[3] = 0x7a4847 For InfoType 80000005 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 80000006 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x8006040 CPUInfo[3] = 0x0 For InfoType 80000007 CPUInfo[0] = 0x0 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 For InfoType 80000008 CPUInfo[0] = 0x3024 CPUInfo[1] = 0x0 CPUInfo[2] = 0x0 CPUInfo[3] = 0x0 CPU String: GenuineIntel Stepping ID = 10 Model = 4 Family = 15 CLFLUSH cache line size = 64 Logical Processor Count = 2 APIC Physical ID = 1 The following features are supported: SSE3 MONITOR/MWAIT CPL Qualified Debug Store Enhanced Intel SpeedStep Technology Thermal Monitor 2 L1 Context ID CMPXCHG16B Instruction xTPR Update Control x87 FPU On Chip Virtual-8086 Mode Enhancement Debugging Extensions Page Size Extensions Time Stamp Counter RDMSR and WRMSR Support Physical Address Extensions Machine Check Exception CMPXCHG8B Instruction APIC On Chip SYSENTER and SYSEXIT Memory Type Range Registers PTE Global Bit Machine Check Architecture Conditional Move/Compare Instruction Page Attribute Table 36-bit Page Size Extension CFLUSH Extension Debug Store Thermal Monitor and Clock Ctrl MMX Technology FXSAVE/FXRSTOR SSE Extensions SSE2 Extensions Self Snoop Multithreading Technology Thermal Monitor Pending Break Enable LAHF/SAHF in 64-bit mode 64 bit Technology CPU Brand String: Intel(R) Pentium(R) 4 CPU 3.60GHz Cache Line Size = 64 L2 Associativity = 6 Cache Size = 2048K Number of Cores = 1 ECX Index 0 Type: Data Cache Level = 2 Self Initializing Is Not Fully Associatve Max Threads = 2 System Line Size = 64 Physical Line Partions = 1 Ways of Associativity = 8 Number of Sets = 32 ECX Index 1 Type: Unified Cache Level = 3 Self Initializing Is Not Fully Associatve Max Threads = 2 System Line Size = 64 Physical Line Partions = 2 Ways of Associativity = 8 Number of Sets = 2048

See Also

Reference

Compiler Intrinsics

Change History

Date

History

Reason

July 2008

Added information about the new intrinsic __cpuidex.

SP1 feature change.