This is a collection of Intel®’ IA32® Software Developer's Manuals (URL of the day) and AMD' AMD64 Architecture Programmer's Manual together with the related specifications, application notes, white papers, and change logs. The collection aims to keep all available revisions. It was originally created by Michal Necasek, see OS/2 Museum.

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VSQRT

Square Root calculates the square root of the value in a floating-point register and writes the result to another floating-point register.

Depending on settings in the CPACR, NSACR, HCPTR, and FPEXC registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be UNDEFINED, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.

It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .

A1

Decode for all variants of this encoding

if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then Undefined(); end; if size == '01' && cond != '1110' then UnpredictableProcedure(); end; if FPSCR().Len != '000' || FPSCR().Stride != '00' then Undefined(); end; let esize : integer{} = 8 << UInt(size); let d : integer = if size == '11' then UInt(D::Vd) else UInt(Vd::D); let m : integer = if size == '11' then UInt(M::Vm) else UInt(Vm::M);

CONSTRAINED UNPREDICTABLE behavior

If size == '01' && cond != '1110', then one of the following behaviors must occur:

• The instruction is undefined.
• The instruction executes as if it passes the Condition code check.
• The instruction executes as NOP. This means it behaves as if it fails the Condition code check.

T1

Decode for all variants of this encoding

if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then Undefined(); end; if size == '01' && InITBlock() then UnpredictableProcedure(); end; if FPSCR().Len != '000' || FPSCR().Stride != '00' then Undefined(); end; let esize : integer{} = 8 << UInt(size); let d : integer = if size == '11' then UInt(D::Vd) else UInt(Vd::D); let m : integer = if size == '11' then UInt(M::Vm) else UInt(Vm::M);

CONSTRAINED UNPREDICTABLE behavior

If size == '01' && InITBlock(), then one of the following behaviors must occur:

• The instruction is undefined.
• The instruction executes as if it passes the Condition code check.
• The instruction executes as NOP. This means it behaves as if it fails the Condition code check.