FMAXNMP (scalar)

Floating-point maximum number of pair of elements (scalar)

This instruction compares two vector elements in the source SIMD&FP register and writes the largest of the floating-point values as a scalar to the destination SIMD&FP register.

Regardless of the value of FPCR.AH, the behavior is as follows for each pairwise operation:

• Negative zero compares less than positive zero.
• If one element is numeric and the other is a quiet NaN, the result is the numeric value.
• When FPCR.DN is 0, if either element is a signaling NaN or if both elements are NaNs, the result is a quiet NaN.
• When FPCR.DN is 1, if either element is a signaling NaN or if both elements are NaNs, the result is Default NaN.

This instruction can generate a floating-point exception. Depending on the settings in FPCR, the exception results in either a flag being set in FPSR or a synchronous exception being generated. For more information, see Floating-point exceptions and exception traps.

Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.

It has encodings from 2 classes: Half-precision and Single-precision and double-precision

Half-precision
(FEAT_AdvSIMD && FEAT_FP16)

Decode for this encoding

if !IsFeatureImplemented(FEAT_AdvSIMD) || !IsFeatureImplemented(FEAT_FP16) then EndOfDecode(Decode_UNDEF); end; if sz == '1' then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let esize : integer{} = 16; let datasize : integer{} = 32;

Single-precision and double-precision
(FEAT_AdvSIMD)

Decode for this encoding

if !IsFeatureImplemented(FEAT_AdvSIMD) then EndOfDecode(Decode_UNDEF); end; let d : integer{} = UInt(Rd); let n : integer{} = UInt(Rn); let esize : integer{} = 32 << UInt(sz); let datasize : integer{} = esize * 2;