Proof: Byte 1 Stays the Same 1

Let's prove the following theorem:

if the following are true:
  • instruction #1 is addi dst=2 src=0 imm=1
  • the PC at time 1 = 1
  • value of cell 1 at time 1 = 0

then value of cell 1 at time 2 = 0

Instructions
Memory Cells
Program Counter Time
0 0
LW Computer Simulator

Proof:

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Given
1 instruction #1 is addi dst=2 src=0 imm=1
2 the PC at time 1 = 1
3 value of cell 1 at time 1 = 0
Proof Table
# Claim Reason
1 not (1 = 2) not (1 = 2)
2 value of cell 1 at time (1 + 1) = value of cell 1 at time 1 if instruction #1 is addi dst=2 src=0 imm=1 and the PC at time 1 = 1 and not (1 = 2), then value of cell 1 at time (1 + 1) = value of cell 1 at time 1
3 1 + 1 = 2 1 + 1 = 2
4 value of cell 1 at time (1 + 1) = value of cell 1 at time 2 if 1 + 1 = 2, then value of cell 1 at time (1 + 1) = value of cell 1 at time 2
5 value of cell 1 at time 2 = value of cell 1 at time 1 if value of cell 1 at time (1 + 1) = value of cell 1 at time 2 and value of cell 1 at time (1 + 1) = value of cell 1 at time 1, then value of cell 1 at time 2 = value of cell 1 at time 1
6 value of cell 1 at time 2 = 0 if value of cell 1 at time 2 = value of cell 1 at time 1 and value of cell 1 at time 1 = 0, then value of cell 1 at time 2 = 0

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