INCB, INCD, INCH, INCW (scalar)

Increment scalar by multiple of predicate constraint element count

Determines the number of active elements implied by the named predicate constraint, multiplies that by an immediate in the range 1 to 16 inclusive, and then uses the result to increment the scalar destination.

The named predicate constraint limits the number of active elements in a single predicate to:

Unspecified or out of range constraint encodings generate an empty predicate or zero element count rather than Undefined Instruction exception.

It has encodings from 4 classes: Byte , Doubleword , Halfword and Word

Byte

313029282726252423222120191817161514131211109876543210
000001000011imm4111000patternRdn
size<1>size<0>D

INCB <Xdn>{, <pattern>{, MUL #<imm>}}

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 8; integer dn = UInt(Rdn); bits(5) pat = pattern; integer imm = UInt(imm4) + 1;

Doubleword

313029282726252423222120191817161514131211109876543210
000001001111imm4111000patternRdn
size<1>size<0>D

INCD <Xdn>{, <pattern>{, MUL #<imm>}}

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 64; integer dn = UInt(Rdn); bits(5) pat = pattern; integer imm = UInt(imm4) + 1;

Halfword

313029282726252423222120191817161514131211109876543210
000001000111imm4111000patternRdn
size<1>size<0>D

INCH <Xdn>{, <pattern>{, MUL #<imm>}}

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 16; integer dn = UInt(Rdn); bits(5) pat = pattern; integer imm = UInt(imm4) + 1;

Word

313029282726252423222120191817161514131211109876543210
000001001011imm4111000patternRdn
size<1>size<0>D

INCW <Xdn>{, <pattern>{, MUL #<imm>}}

if !HaveSVE() && !HaveSME() then UNDEFINED; constant integer esize = 32; integer dn = UInt(Rdn); bits(5) pat = pattern; integer imm = UInt(imm4) + 1;

Assembler Symbols

<Xdn>

Is the 64-bit name of the source and destination general-purpose register, encoded in the "Rdn" field.

<pattern>

Is the optional pattern specifier, defaulting to ALL, encoded in pattern:

pattern <pattern>
00000 POW2
00001 VL1
00010 VL2
00011 VL3
00100 VL4
00101 VL5
00110 VL6
00111 VL7
01000 VL8
01001 VL16
01010 VL32
01011 VL64
01100 VL128
01101 VL256
0111x #uimm5
101x1 #uimm5
10110 #uimm5
1x0x1 #uimm5
1x010 #uimm5
1xx00 #uimm5
11101 MUL4
11110 MUL3
11111 ALL
<imm>

Is the immediate multiplier, in the range 1 to 16, defaulting to 1, encoded in the "imm4" field.

Operation

CheckSVEEnabled(); integer count = DecodePredCount(pat, esize); constant integer VL = CurrentVL; bits(64) operand1 = X[dn, 64]; X[dn, 64] = operand1 + (count * imm);

Operational information

If FEAT_SVE2 is implemented or FEAT_SME is implemented, then if PSTATE.DIT is 1:


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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