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VMAXNM

This instruction determines the floating-point maximum number.

It handles NaNs in consistence with the IEEE 754-2008 specification. It returns the numerical operand when one operand is numerical and the other is a quiet NaN, but otherwise the result is identical to floating-point VMAX.

This instruction is not conditional.

It has encodings from the following instruction sets: A32 ( A1 and A2 ) and T32 ( T1 and T2 ) .

A1

Decode for all variants of this encoding

if Q == '1' && (Vd[0] == '1' || Vn[0] == '1' || Vm[0] == '1') then Undefined(); end; if sz == '1' && !IsFeatureImplemented(FEAT_FP16) then Undefined(); end; let maximum : boolean = (op == '0'); let advsimd : boolean = TRUE; let esize : integer{} = 32 >> UInt(sz); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2;

A2

Decode for all variants of this encoding

if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then Undefined(); end; let advsimd : boolean = FALSE; let maximum : boolean = (op == '0'); let esize : integer{} = 8 << UInt(size); let d : integer = if size == '11' then UInt(D::Vd) else UInt(Vd::D); let n : integer = if size == '11' then UInt(N::Vn) else UInt(Vn::N); let m : integer = if size == '11' then UInt(M::Vm) else UInt(Vm::M); let regs : integer = ARBITRARY : integer; let elements : integer = ARBITRARY : integer;

T1

Decode for all variants of this encoding

if InITBlock() then UnpredictableProcedure(); end; if Q == '1' && (Vd[0] == '1' || Vn[0] == '1' || Vm[0] == '1') then Undefined(); end; if sz == '1' && !IsFeatureImplemented(FEAT_FP16) then Undefined(); end; let maximum : boolean = (op == '0'); let advsimd : boolean = TRUE; let esize : integer{} = 32 >> UInt(sz); let elements : integer = 64 DIV esize; let d : integer = UInt(D::Vd); let n : integer = UInt(N::Vn); let m : integer = UInt(M::Vm); let regs : integer = if Q == '0' then 1 else 2;

CONSTRAINED UNPREDICTABLE behavior

If 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.

T2

Decode for all variants of this encoding

if InITBlock() then UnpredictableProcedure(); end; if size == '00' || (size == '01' && !IsFeatureImplemented(FEAT_FP16)) then Undefined(); end; let advsimd : boolean = FALSE; let maximum : boolean = (op == '0'); let esize : integer{} = 8 << UInt(size); let d : integer = if size == '11' then UInt(D::Vd) else UInt(Vd::D); let n : integer = if size == '11' then UInt(N::Vn) else UInt(Vn::N); let m : integer = if size == '11' then UInt(M::Vm) else UInt(Vm::M); let regs : integer = ARBITRARY : integer; let elements : integer = ARBITRARY : integer;

CONSTRAINED UNPREDICTABLE behavior

If 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.

Assembler Symbols