Move Top writes an immediate value to the top halfword of the destination register. It does not affect the contents of the bottom halfword.
It has encodings from the following instruction sets: A32 ( A1 ) and T32 ( T1 ) .
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 |
!= 1111 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 0 | imm4 | Rd | imm12 | ||||||||||||||||||||
cond |
d = UInt(Rd); imm16 = imm4:imm12; if d == 15 then UNPREDICTABLE;
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 | 0 | i | 1 | 0 | 1 | 1 | 0 | 0 | imm4 | 0 | imm3 | Rd | imm8 |
d = UInt(Rd); imm16 = imm4:i:imm3:imm8; if d == 15 then UNPREDICTABLE; // ARMv8-A removes UNPREDICTABLE for R13
For more information about the constrained unpredictable behavior of this instruction, see Architectural Constraints on UNPREDICTABLE behaviors.
<c> |
<q> |
<Rd> |
Is the general-purpose destination register, encoded in the "Rd" field. |
if ConditionPassed() then EncodingSpecificOperations(); R[d]<31:16> = imm16; // R[d]<15:0> unchanged
Internal version only: isa v00_79, pseudocode v34.2 ; Build timestamp: 2017-12-19T15:42
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