Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

## SHA512H2

SHA512 Hash update part 2 takes the values from the three 128-bit source SIMD&FP registers and produces a 128-bit output value that combines the sigma0 and majority functions of two iterations of the SHA512 computation. It returns this value to the destination SIMD&FP register.

This instruction is implemented only when FEAT_SHA512 is implemented.

### Advanced SIMD
(FEAT_SHA512)

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 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | Rm | 1 | 0 | 0 | 0 | 0 | 1 | Rn | Rd

####

SHA512H2 <Qd>, <Qn>, <Vm>.2D

if !IsFeatureImplemented(FEAT_SHA512) then UNDEFINED; integer d = UInt(Rd); integer n = UInt(Rn); integer m = UInt(Rm);

### Assembler Symbols

<Qd> | Is the 128-bit name of the SIMD&FP source and destination register, encoded in the "Rd" field.

<Qn> | Is the 128-bit name of the second SIMD&FP source register, encoded in the "Rn" field.

<Vm> | Is the name of the third SIMD&FP source register, encoded in the "Rm" field.

### Operation

AArch64.CheckFPAdvSIMDEnabled(); bits(128) Vtmp; bits(64) NSigma0; bits(128) x = V[n, 128]; bits(128) y = V[m, 128]; bits(128) w = V[d, 128]; NSigma0 = ROR(y<63:0>, 28) EOR ROR(y<63:0>, 34) EOR ROR(y<63:0>, 39); Vtmp<127:64> = (x<63:0> AND y<127:64>) EOR (x<63:0> AND y<63:0>) EOR (y<127:64> AND y<63:0>); Vtmp<127:64> = (Vtmp<127:64> + NSigma0 + w<127:64>); NSigma0 = ROR(Vtmp<127:64>, 28) EOR ROR(Vtmp<127:64>, 34) EOR ROR(Vtmp<127:64>, 39); Vtmp<63:0> = ((Vtmp<127:64> AND y<63:0>) EOR (Vtmp<127:64> AND y<127:64>) EOR (y<127:64> AND y<63:0>)); Vtmp<63:0> = (Vtmp<63:0> + NSigma0 + w<63:0>); V[d, 128] = Vtmp;

### Operational information

If PSTATE.DIT is 1:

- The execution time of this instruction is independent of:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.
- The response of this instruction to asynchronous exceptions does not vary based on:
  - The values of the data supplied in any of its registers.
  - The values of the NZCV flags.

Base Instructions | SIMD&FP Instructions | SVE Instructions | SME Instructions | Index by Encoding | Shared Pseudocode | Proprietary Notice

Internal version only: isa v33.74, AdvSIMD v29.23, pseudocode v2023-09_rel, sve v2023-09_rc3 ; Build timestamp: 2023-09-27T17:06

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