if (x < array1_size) lfence(); // prevents speculation past here y = array2[ array1[x] * 4096 ];
$ spectre-meltdown-checker --variant 1 | Factor | Impact | |--------|--------| | Requires precise timing | Mitigated by reducing timer resolution | | Depends on branch predictor state | Can be flushed by OS, but not on all CPUs | | Noisy cache channel | Needs many samples (~10k–1M) per byte | | No architectural state leak | Only cache side channel | 10. Conclusion Spectre fundamentally breaks the abstraction that speculative execution is invisible to software. By training branch predictors and measuring cache latencies, an attacker can read arbitrary memory from the same address space. It affects nearly all high‑performance CPUs and requires a combination of hardware fixes, compiler mitigations, and OS isolation to fully contain. spectre 10