Vector Compare Greater Than takes each element in a vector, and compares it with the corresponding element of a second vector. If the first is greater than the second, the corresponding element in the destination vector is set to all ones. Otherwise, it is set to all zeros.
The operand vector elements are the same type, and are signed integers, unsigned integers, or floating-point numbers. The result vector elements are fields the same size as the operand vector elements.
Depending on settings in the CPACR, NSACR, and HCPTR registers, and the Security state and PE mode in which the instruction is executed, an attempt to execute the instruction might be undefined, or trapped to Hyp mode. For more information see Enabling Advanced SIMD and floating-point support.
This instruction is used by the pseudo-instruction VCLT (register).
It has encodings from the following instruction sets: A32 ( A1 and A2 ) and T32 ( T1 and T2 ) .
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | 1 | 0 | 0 | 1 | U | 0 | D | size | Vn | Vd | 0 | 0 | 1 | 1 | N | Q | M | 0 | Vm | ||||||||||
if Q == '1' && (Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1') then UNDEFINED; if size == '11' then UNDEFINED; vtype = if U == '1' then VCGTtype_unsigned else VCGTtype_signed; esize = 8 << UInt(size); elements = 64 DIV esize; d = UInt(D:Vd); n = UInt(N:Vn); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;
| 31 | 30 | 29 | 28 | 27 | 26 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 18 | 17 | 16 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | D | 1 | sz | Vn | Vd | 1 | 1 | 1 | 0 | N | Q | M | 0 | Vm | |||||||||
if Q == '1' && (Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1') then UNDEFINED; if sz == '1' && !HaveFP16Ext() then UNDEFINED; vtype = VCGTtype_fp; integer esize; integer elements; case sz of when '0' esize = 32; elements = 2; when '1' esize = 16; elements = 4; d = UInt(D:Vd); n = UInt(N:Vn); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | U | 1 | 1 | 1 | 1 | 0 | D | size | Vn | Vd | 0 | 0 | 1 | 1 | N | Q | M | 0 | Vm | ||||||||||
if Q == '1' && (Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1') then UNDEFINED; if size == '11' then UNDEFINED; vtype = if U == '1' then VCGTtype_unsigned else VCGTtype_signed; esize = 8 << UInt(size); elements = 64 DIV esize; d = UInt(D:Vd); n = UInt(N:Vn); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;
| 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 | 15 | 14 | 13 | 12 | 11 | 10 | 9 | 8 | 7 | 6 | 5 | 4 | 3 | 2 | 1 | 0 |
| 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | D | 1 | sz | Vn | Vd | 1 | 1 | 1 | 0 | N | Q | M | 0 | Vm | |||||||||
if Q == '1' && (Vd<0> == '1' || Vn<0> == '1' || Vm<0> == '1') then UNDEFINED; if sz == '1' && !HaveFP16Ext() then UNDEFINED; if sz == '1' && InITBlock() then UNPREDICTABLE; vtype = VCGTtype_fp; integer esize; integer elements; case sz of when '0' esize = 32; elements = 2; when '1' esize = 16; elements = 4; d = UInt(D:Vd); n = UInt(N:Vn); m = UInt(M:Vm); regs = if Q == '0' then 1 else 2;
If sz == '1' && InITBlock(), then one of the following behaviors must occur:
| <c> |
For encoding A1 and A2: see Standard assembler syntax fields. This encoding must be unconditional. |
|
For encoding T1 and T2: see Standard assembler syntax fields. |
| <q> |
| <Qd> |
Is the 128-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field as <Qd>*2. |
| <Qn> |
Is the 128-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field as <Qn>*2. |
| <Qm> |
Is the 128-bit name of the second SIMD&FP source register, encoded in the "M:Vm" field as <Qm>*2. |
| <Dd> |
Is the 64-bit name of the SIMD&FP destination register, encoded in the "D:Vd" field. |
| <Dn> |
Is the 64-bit name of the first SIMD&FP source register, encoded in the "N:Vn" field. |
| <Dm> |
Is the 64-bit name of the second SIMD&FP source register, encoded in the "M:Vm" field. |
if ConditionPassed() then EncodingSpecificOperations(); CheckAdvSIMDEnabled(); for r = 0 to regs-1 for e = 0 to elements-1 op1 = Elem[D[n+r],e,esize]; op2 = Elem[D[m+r],e,esize]; boolean test_passed; case vtype of when VCGTtype_signed test_passed = (SInt(op1) > SInt(op2)); when VCGTtype_unsigned test_passed = (UInt(op1) > UInt(op2)); when VCGTtype_fp test_passed = FPCompareGT(op1, op2, StandardFPSCRValue()); Elem[D[d+r],e,esize] = if test_passed then Ones(esize) else Zeros(esize);
If CPSR.DIT is 1 and this instruction passes its condition execution check and is operating only on integer vector elements, then the following apply:
Internal version only: isa v01_31, pseudocode v2023-06_rel, sve v2023-06_rel ; Build timestamp: 2023-07-04T18:06
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