tango.core.tools.Cpuid

Identify the characteristics of the host CPU, providing information about cache sizes and assembly optimisation hints.
Some of this information was extremely difficult to track down. Some of the documents below were found only in cached versions stored by search engines! This code relies on information found in:

Authors:

Don Clugston, Tomas Lindquist Olsen

Bugs:

Currently only works on x86 CPUs. Many processors have bugs in their microcode for the CPUID instruction, so sometimes the cache information may be incorrect.
struct CacheInfo [public] #
Cache size and behaviour.
uint size #
Size of the cache, in kilobytes, per CPU. For L1 unified (data + code) caches, this size is half the physical size. (we don't halve it for larger sizes, since normally data size is much greater than code size for critical loops).
ubyte associativity #
Number of ways of associativity, eg:
1 = direct mapped
2 = 2-way set associative
3 = 3-way set associative
ubyte.max = fully associative
uint lineSize #
Number of bytes read into the cache when a cache miss occurs.
char[] vendor() [public] #
Returns vendor string, for display purposes only. Do NOT use this to determine features! Note that some CPUs have programmable vendorIDs.
char[] processor() [public] #
Returns processor string, for display purposes only
CacheInfo[5] datacache [public] #
The data caches. If there are fewer than 5 physical caches levels, the remaining levels are set to uint.max (== entire memory space)
bool x87onChip() [public] #
Does it have an x87 FPU on-chip?
bool mmx() [public] #
Is MMX supported?
bool sse() [public] #
Is SSE supported?
bool sse2() [public] #
Is SSE2 supported?
bool sse3() [public] #
Is SSE3 supported?
bool ssse3() [public] #
Is SSSE3 supported?
bool sse41() [public] #
Is SSE4.1 supported?
bool sse42() [public] #
Is SSE4.2 supported?
bool sse4a() [public] #
Is SSE4a supported?
bool amd3dnow() [public] #
Is AMD 3DNOW supported?
bool amd3dnowExt() [public] #
Is AMD 3DNOW Ext supported?
bool amdMmx() [public] #
Are AMD extensions to MMX supported?
bool hasFxsr() [public] #
Is fxsave/fxrstor supported?
bool hasCmov() [public] #
Is cmov supported?
bool hasRdtsc() [public] #
Is rdtsc supported?
bool hasCmpxchg8b() [public] #
Is cmpxchg8b supported?
bool hasCmpxchg16b() [public] #
Is cmpxchg8b supported?
bool hasSysEnterSysExit() [public] #
Is SYSENTER/SYSEXIT supported?
bool has3dnowPrefetch() [public] #
Is 3DNow prefetch supported?
bool hasLahfSahf() [public] #
Are LAHF and SAHF supported in 64-bit mode?
bool hasPopcnt() [public] #
Is POPCNT supported?
bool hasLzcnt() [public] #
Is LZCNT supported?
bool isX86_64() [public] #
Is this an Intel64 or AMD 64?
bool isItanium() [public] #
Is this an IA64 (Itanium) processor?
bool hyperThreading() [public] #
Is hyperthreading supported?
uint threadsPerCPU() [public] #
Returns number of threads per CPU
uint coresPerCPU() [public] #
Returns number of cores in CPU
bool preferAthlon() [public] #
Optimisation hints for assembly code. For forward compatibility, the CPU is compared against different microarchitectures. For 32-bit X86, comparisons are made against the Intel PPro/PII/PIII/PM family.
The major 32-bit x86 microarchitecture 'dynasties' have been: (1) Intel P6 (PentiumPro, PII, PIII, PM, Core, Core2). (2) AMD Athlon (K7, K8, K10). (3) Intel NetBurst (Pentium 4, Pentium D). (4) In-order Pentium (Pentium1, PMMX, Atom) Other early CPUs (Nx586, AMD K5, K6, Centaur C3, Transmeta, Cyrix, Rise) were mostly in-order. Some new processors do not fit into the existing categories: Intel Atom 230/330 (family 6, model 0x1C) is an in-order core. Centaur Isiah = VIA Nano (family 6, model F) is an out-of-order core.

Within each dynasty, the optimisation techniques are largely identical (eg, use instruction pairing for group 4). Major instruction set improvements occur within each dynasty. Does this CPU perform better on AMD K7 code than PentiumPro..Core2 code?

bool preferPentium4() [public] #
Does this CPU perform better on Pentium4 code than PentiumPro..Core2 code?
bool preferPentium1() [public] #
Does this CPU perform better on Pentium I code than Pentium Pro code?
uint stepping [public] #
uint model [public] #
uint family [public] #
Processor type (vendor-dependent). This should be visible ONLY for display purposes.