Instruction
VSTMXCSR
Stores the MXCSR register, the SSE control and status bits, to memory; the VEX form of STMXCSR.
- Extensions
- Forms
- 1 (1 VEX)
- Data
- Intel XED v2026.08.23
Forms
| Instruction | Encoding | Requires |
|---|---|---|
VSTMXCSR m32
VSTMXCSR_MEMd | VEX.LZ.NP.0F.WIG AE /3 | AVX |
Operation
What the forms do, in pseudocode that our tests run against results recorded on real processors. How to read.
dest.write(mxcsr) # the bits it lacks as zeros
Run on AMD Zen 5 (EPYC 9645): 2 cases.
Operands
| Operand | Kind | Action |
|---|---|---|
VSTMXCSR m32 | ||
m32 | explicit | write |
MXCSR | implicit | read |
Flags
None: XED records no flag that the forms test or change.
Exceptions
The exception class is XED's name for the set of exception conditions that a form follows. How to read.
- All forms
avx-type-5
CPUID and processors
Each form belongs to an XED ISA set. A form can be used when the processor reports every CPUID bit of one of its ISA set's alternatives.
| ISA set | CPUID | Processors |
|---|---|---|
AVX | AVX | Sandy Bridge, Ivy Bridge, Haswell, Broadwell, Skylake, Comet Lake, Cannon Lake, Ice Lake (client), Tiger Lake, Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Skylake-SP, Cascade Lake, Cooper Lake, Ice Lake (server), Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Sierra Forest, Clearwater Forest, Knights Landing, Knights Mill, Bulldozer, Piledriver, Zen, Zen+, Zen 2, Zen 3, Zen 4, Zen 5, Zen 6 |
More AVX instructions
- VPTEST
- VPUNPCKHBW
- VPUNPCKHDQ
- VPUNPCKHQDQ
- VPUNPCKHWD
- VPUNPCKLBW
- VPUNPCKLDQ
- VPUNPCKLQDQ
- VPUNPCKLWD
- VPXOR
- VRCPPS
- VRCPSS
- VROUNDPD
- VROUNDPS
- VROUNDSD
- VROUNDSS
- VRSQRTPS
- VRSQRTSS
- VSHUFPD
- VSHUFPS
- VSQRTPD
- VSQRTPS
- VSQRTSD
- VSQRTSS
- VSUBPD
- VSUBPS
- VSUBSD
- VSUBSS
- VTESTPD
- VTESTPS
- VUCOMISD
- VUCOMISS
- VUNPCKHPD
- VUNPCKHPS
- VUNPCKLPD
- VUNPCKLPS
- VXORPD
- VXORPS
- VZEROALL
- VZEROUPPER
Sources
- Intel XED v2026.08.23 (commit
0bcb6237345c): forms, encodings, operands, flags, exception classes, attributes, ISA sets, CPUID bits and chip model. - The CPU data of x86-64.net: Zen 3 to Zen 6, from GCC’s
-marchfeature sets and AMD’s Processor Programming References, which the page of each processor cites. - Intel 64 and IA-32 Architectures Software Developer's Manual, Volume 2 (325383-093, September 2026): Volume 2B, page 4-676 (STMXCSR)
- Intel 64 and IA-32 Architectures Software Developer's Manual, Volume 1 (253665-093, September 2026)
The tables are derived from Intel XED, Copyright Intel Corporation, licensed under the Apache License 2.0; x86-64.net converted and reformatted them. The text is our own.