  Symbolic quick error detection (SQED) has greatly improved efficiency in
formal chip verification. However, it has a limitation in detecting
single-instruction bugs due to its reliance on the self-consistency property.
To address this, we propose a new variant called symbolic quick error detection
by semantically equivalent program execution (SEPE-SQED), which utilizes
program synthesis techniques to find sequences with equivalent meanings to
original instructions. SEPE-SQED effectively detects single-instruction bugs by
differentiating their impact on the original instruction and its semantically
equivalent program (instruction sequence). To manage the search space
associated with program synthesis, we introduce the CEGIS based on the highest
priority first algorithm. The experimental results show that our proposed CEGIS
approach improves the speed of generating the desired set of equivalent
programs by 50% in time compared to previous methods. Compared to SQED,
SEPE-SQED offers a wider variety of instruction combinations and can provide a
shorter trace for triggering bugs in certain scenarios.
