BFCLAMP

BFloat16 floating-point clamp to minimum/maximum number

Clamp each BFloat16 element in the destination vector to between the BFloat16 minimum value in the corresponding element of the first source vector and the BFloat16 maximum value in the corresponding element of the second source vector and destructively place the clamped results in the corresponding elements of the destination vector.

Regardless of the value of FPCR.AH, the behavior is as follows for each minimum number and maximum number operation:

This instruction follows SVE2.1 non-widening BFloat16 numerical behaviors.

This instruction is unpredicated.

ID_AA64ZFR0_EL1.B16B16 indicates whether this instruction is implemented.

SVE2
(FEAT_SVE_B16B16)

313029282726252423222120191817161514131211109876543210
01100100001Zm001001ZnZd
size<1>size<0>

BFCLAMP <Zd>.H, <Zn>.H, <Zm>.H

if (!HaveSVE2() && !HaveSME2()) || !IsFeatureImplemented(FEAT_SVE_B16B16) then UNDEFINED; integer n = UInt(Zn); integer m = UInt(Zm); integer d = UInt(Zd);

Assembler Symbols

<Zd>

Is the name of the destination scalable vector register, encoded in the "Zd" field.

<Zn>

Is the name of the first source scalable vector register, encoded in the "Zn" field.

<Zm>

Is the name of the second source scalable vector register, encoded in the "Zm" field.

Operation

CheckSVEEnabled(); constant integer VL = CurrentVL; constant integer PL = VL DIV 8; constant integer elements = VL DIV 16; bits(VL) result; bits(VL) operand1 = Z[n, VL]; bits(VL) operand2 = Z[m, VL]; bits(VL) operand3 = Z[d, VL]; for e = 0 to elements-1 bits(16) element1 = Elem[operand1, e, 16]; bits(16) element2 = Elem[operand2, e, 16]; bits(16) element3 = Elem[operand3, e, 16]; Elem[result, e, 16] = BFMinNum(BFMaxNum(element1, element3, FPCR), element2, FPCR); Z[d, VL] = result;

Operational information

This instruction might be immediately preceded in program order by a MOVPRFX instruction. The MOVPRFX instruction must conform to all of the following requirements, otherwise the behavior of the MOVPRFX and this instruction is unpredictable:


Internal version only: aarchmrs v2023-12_rel, pseudocode v2023-12_rel, sve v2023-12_rel ; Build timestamp: 2023-12-15T16:46

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