LDR (literal, SIMD&FP)

Load SIMD&FP Register (PC-relative literal). This instruction loads a SIMD&FP register from memory. The address that is used for the load is calculated from the PC value and an immediate offset.

Depending on the settings in the CPACR_EL1, CPTR_EL2, and CPTR_EL3 registers, and the current Security state and Exception level, an attempt to execute the instruction might be trapped.

313029282726252423222120191817161514131211109876543210
opc011100imm19Rt

32-bit (opc == 00)

LDR <St>, <label>

64-bit (opc == 01)

LDR <Dt>, <label>

128-bit (opc == 10)

LDR <Qt>, <label>

integer t = UInt(Rt); integer size; bits(64) offset; case opc of when '00' size = 4; when '01' size = 8; when '10' size = 16; when '11' UNDEFINED; offset = SignExtend(imm19:'00', 64); boolean tag_checked = FALSE;

Assembler Symbols

<Dt>

Is the 64-bit name of the SIMD&FP register to be loaded, encoded in the "Rt" field.

<Qt>

Is the 128-bit name of the SIMD&FP register to be loaded, encoded in the "Rt" field.

<St>

Is the 32-bit name of the SIMD&FP register to be loaded, encoded in the "Rt" field.

<label>

Is the program label from which the data is to be loaded. Its offset from the address of this instruction, in the range +/-1MB, is encoded as "imm19" times 4.

Operation

bits(64) address = PC[] + offset; bits(size*8) data; if HaveMTE2Ext() then SetTagCheckedInstruction(tag_checked); CheckFPEnabled64(); data = Mem[address, size, AccType_VEC]; V[t] = data;

Operational information

If PSTATE.DIT is 1, the timing of this instruction is insensitive to the value of the data being loaded or stored.


Internal version only: isa v33.11seprel, AdvSIMD v29.05, pseudocode v2021-09_rel, sve v2021-09_rc3d ; Build timestamp: 2021-10-06T11:41

Copyright © 2010-2021 Arm Limited or its affiliates. All rights reserved. This document is Non-Confidential.