"features" in ARM Linux's /proc/cpuinfo

32-bit ARM

26bit	Program Counter is 26-bit long
crunch	MaverickCrunch instructoin extension. Now obsolete.
edsp	DSP Enhancement instructions
evtstrm	Virtual event stream
fastmult	Fast multiplication
fpa	Floating Point Accelerator instructions. Now obsolete.
half	?
idiv	Integer divide instructions available in both ARM and Thumb
idiva	Integer divide instructions available in ARM only
idivt	Integer divide instructions available in Thumb only
iwmmxt	Intel Wireless MMX Technology, an implementation of MMX on embedded processors.
java	Jazelle technology
lpae	Atomic ldrd/strd instructions
neon	NEON SIMD instructions
swp	SWP (SWaP) instruction, which is used to implement a binary semaphore (mutex)
thumb	Thumb instructions
thumbee	Thumb Execution Environment
tls	Thread local storage
vfp	Vector Floating Point instruction extension
vfpv3	Vector Floating Point instruction extension version 3, with 32 double-precision registers
vfpv3d16	Vector Floating Point instruction extension version 3, with 16 double-precision registers
vfpv4	Vector Floating Point instruction extension version 4

64-bit ARM

aes	ARMv8-a AES crypto extension
afp	Alternate floating-point behavior
asimd	Advanced SIMD instructions
asimddp	Advanced SIMD dot product instructions
asimdfhm	Half-precision floating-point FMLAL (Fused Multiply-Add to accumulator) instruction
asimdhp
asimdrdm	Rounding double multiply accumulate
atomics
bf16	Brain half-precision floating-point instructions
bti	Branch target identification
cpuid
crc32	CRC extension
dcpodp	DC CVADP instruction
dcpop	DC CVAP (Data or unified Cache line Clean by VA to PoP) instruction
dgh	Data Gathering Hint instruction
dit	Data Independent Timing instructions
ebf16	Extended brain half-precision floating-point instructions
ecv	Enhanced counter virtualization
evtstrm
fcma	Complex number addition and multiplication
flagm	Condition flag manipulation instructions
flagm2	Condition flag manipulation instructions version 2
fp	Floating-point instructions
fphp	Half-precision floating-point
frint	Floating-point Round to Integer instructions
i8mm	8-bit Integer Matrix Multiply instruction
ilrcpc
jscvt	Suport for JavaScript conversion from double precision floating point values to integers
lrcpc	Load-acquire RCpc instructions
mte	ARMv8.5-A Memory Tagging Extension
mte3
paca	Pointer authentication (for address authentication)
pacg	Pointer authentication (for generic authentication)
pmull	ARMv8-A Polynomial Multiply Long crypto extension
rng	ARMv8.5-A Random Number instruction
rpres	Increased precision of Reciprocal Estimate and Reciprocal Square Root Estimate
sb	Speculation Barrier instruction
sha1	ARMv8-a SHA1 crypto extension
sha2	ARMv8-a SHA2 crypto extension
sha3	ARMv8.2-A SHA3 crypto extension
sha512	ARMv8.2-A SHA512 crypto extension
sm3	ARMv8.2-A SM3 crypto extension
sm4	ARMv8.2-A SM4 crypto extension
sme
sme_b16f32
sme_f16f32
sme_f32f32
sme_f64f64
sme_fa64
sme_i16i64
sme_i8i32
ssbs	Speculative Store Bypass Safe instruction
sve	Scalable Vector Extension
sve2	ARMv8-A Scalable Vector Extension 2
sveaes	SVE AES instruction
svebf16	SVE brain half-precision floating-point instructions
svebitperm	SVE bitperm instruction
svef32mm	SVE single-precision floating-point matrix multiply instruction
svef64mm	SVE double-precision floating-point matrix multiply instruction
svei8mm	SVE 8-bit Integer Matrix Multiply instruction
svepmull	Polynomial Multiply Long crypto extension
svesha3	SHA512 and SHA3 crypto extension
svesm4	SM4 crypto extension
uscat
wfxt	WFET (Wait For Event with Timeout) and WFIT (Wait For Interrupt with Timeout) instructions

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