FAC<cc>

Floating-point absolute compare vectors.

Compare active absolute values of floating-point elements in the first source vector with corresponding absolute values of elements in the second source vector, and place the boolean results of the specified comparison in the corresponding elements of the destination predicate. Inactive elements in the destination predicate register are set to zero. Does not set the condition flags.

The <cc> symbol specifies one of the standard ARM condition codes: GE, GT, LE, or LT.

This instruction is used by the aliases FACLE and FACLT . See Alias Conditions below for details of when each alias is preferred.

It has encodings from 2 classes: Greater than and Greater than or equal

Greater than

313029282726252423222120191817161514131211109876543210
01100101size0Zm111PgZn1Pd

Greater than

FACGT <Pd>.<T>, <Pg>/Z, <Zn>.<T>, <Zm>.<T>

if !HaveSVE() then UNDEFINED; if size == '00' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer m = UInt(Zm); integer d = UInt(Pd); SVECmp op = Cmp_GT;

Greater than or equal

313029282726252423222120191817161514131211109876543210
01100101size0Zm110PgZn1Pd

Greater than or equal

FACGE <Pd>.<T>, <Pg>/Z, <Zn>.<T>, <Zm>.<T>

if !HaveSVE() then UNDEFINED; if size == '00' then UNDEFINED; integer esize = 8 << UInt(size); integer g = UInt(Pg); integer n = UInt(Zn); integer m = UInt(Zm); integer d = UInt(Pd); SVECmp op = Cmp_GE;

Assembler Symbols

<Pd>

Is the name of the destination scalable predicate register, encoded in the "Pd" field.

<T> Is the size specifier, encoded in size:
size <T>
00 RESERVED
01 H
10 S
11 D
<Pg>

Is the name of the governing scalable predicate register P0-P7, encoded in the "Pg" 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.

Alias Conditions

AliasIs preferred when
FACLENever
FACLTNever

Operation

CheckSVEEnabled(); integer elements = VL DIV esize; bits(PL) mask = P[g]; bits(VL) operand1 = Z[n]; bits(VL) operand2 = Z[m]; bits(PL) result; for e = 0 to elements-1 bits(esize) element1 = Elem[operand1, e, esize]; bits(esize) element2 = Elem[operand2, e, esize]; if ElemP[mask, e, esize] == '1' then case op of when Cmp_GE res = FPCompareGE(FPAbs(element1), FPAbs(element2), FPCR); when Cmp_GT res = FPCompareGT(FPAbs(element1), FPAbs(element2), FPCR); ElemP[result, e, esize] = if res then '1' else '0'; else ElemP[result, e, esize] = '0'; P[d] = result;


Release: 00rel5-manual

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