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← Back to Instruction Set: Quick Reference

EQ

Equality check (a == b)

Opcodes 0x0A-0x0B (2 wire formats)

M[dstOffset] = (M[aOffset] == M[bOffset]) ? 1 : 0

Details

Compares two values for equality. Both operands must have the same type tag. The result is a Uint1 (0 or 1).

Gas Costs

Component Value Scales with
L2 Base 12 -
DA Base 0 -
L2 Addressing 3 3 L2 gas per indirect memory offset
3 L2 gas per relative memory offset

* See Gas Metering for details on how gas costs are computed and applied.

Operands

Name Type Description
aOffset Memory offset Memory offset of the first value to compare
bOffset Memory offset Memory offset of the second value to compare
dstOffset Memory offset Memory offset where the result (0 or 1) will be written

Wire Formats

See Wire Format page for an explanation of wire format variants and opcode naming (e.g., why ADD_8 vs ADD_16).

EQ_8 (Opcode 0x0A):

---
title: "EQ_8"
config:
  packet:
    bitsPerRow: 40
---
packet-beta
0-7: "Opcode (0xA)"
8-15: "Addressing modes"
16-23: "Operand: aOffset"
24-31: "Operand: bOffset"
32-39: "Operand: dstOffset"
Loading

EQ_16 (Opcode 0x0B):

---
title: "EQ_16"
config:
  packet:
    bitsPerRow: 64
---
packet-beta
0-7: "Opcode (0xB)"
8-15: "Addressing modes"
16-31: "Operand: aOffset"
32-47: "Operand: bOffset"
48-63: "Operand: dstOffset"
Loading

Addressing Modes

See Addressing page for a detailed explanation.

8-bit bitmask: 2 bits per memory offset operand (indirect flag + relative flag)

Memory offset operands (aOffset, bOffset, dstOffset) are encoded as follows:

---
title: "Addressing Mode Bitmask"
config:
  packet:
    bitWidth: 128
    bitsPerRow: 8
---
packet-beta
  0: "aOffset is indirect"
  1: "aOffset is relative"
  2: "bOffset is indirect"
  3: "bOffset is relative"
  4: "dstOffset is indirect"
  5: "dstOffset is relative"
  6: "Unused"
  7: "Unused"
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Tag Checks

  • T[aOffset] == T[bOffset]

Tag Updates

  • T[dstOffset] = UINT1

Error Conditions

  • TAG_MISMATCH: Operands have different type tags
  • MEMORY_ACCESS_OUT_OF_RANGE: Memory offset operand exceeds addressable memory

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