Principal Design Verification Engineer – CPU Core Frontend

As the pioneers who introduced RISC-V to the world, SiFive is transforming the future of compute by bringing the limitless potential of RISC-V to the highest performance and most data-intensive applications. Our unrivaled compute platforms enable leading technology companies to innovate across markets including artificial intelligence, machine learning, automotive, data center, mobile, and consumer. We collaborate to develop groundbreaking solutions that impact lives globally.

About the role

SiFive is looking for a Principal Design Verification Engineer to lead verification strategy and execution for the CPU Core Frontend in a high-performance out-of-order core. This senior tech-lead role involves defining architecture-aware verification strategies, identifying microarchitectural risks, solving complex frontend verification challenges, and improving verification quality across the broader CPU DV organization. The primary focus is on frontend verification, including branch prediction, instruction fetch, frontend redirects and recovery, prediction training/update behavior, fetch correctness, and interface interactions across the frontend pipeline. The role requires close partnership with architecture, RTL, performance, and verification teams to ensure design intent is captured and signoff quality is achieved.

Responsibilities

• Lead verification planning and execution for CPU frontend functionality in a high-performance out-of-order core, with ownership spanning branch prediction and instruction fetch behavior.
• Define verification strategy, test plans, checkers, scoreboards, assertions, stimulus strategies, and coverage models for frontend microarchitecture and its corner cases.
• Drive verification of branch prediction structures and flows, including direction prediction, indirect target prediction, return prediction, predictor update/training behavior, redirect generation, recovery, and interaction with global history or related predictor state.
• Drive verification of instruction fetch behavior, including fetch packet correctness, PC sequencing, fetch ordering, ITLB/translation interactions, exception reporting, cache-related fetch behavior, and redirect handling after misprediction or flush conditions.
• Partner with architects and designers from early feature-definition stages to review specifications, identify ambiguity, and improve frontend debugability and verification completeness.
• Drive block-level and core-level verification closure for frontend features, including coverage analysis, gap identification, bug triage, and signoff readiness.
• Apply the right verification method for the problem, including simulation, formal techniques, and emulation where appropriate for high-risk or hard-to-observe frontend behaviors.
• Mentor engineers across the organization and shape reusable verification approaches, infrastructure, and methodology for future CPU core generations.
• Work on verification challenges of memory management units reused across several core generations, including hypervisor, virtualization, and guest virtualization.

Requirements

• BS, MS, or PhD in Electrical Engineering, Computer Engineering, Computer Science, or a related field.
• 12+ years of relevant experience in CPU/core or SoC functional verification, with substantial experience in high-performance CPU verification.
• Direct experience with out-of-order CPU core verification and strong understanding of CPU microarchitecture.
• Deep expertise in CPU frontend verification, especially branch prediction and instruction fetch verification.
• Strong knowledge of verification flow methodology, including test planning, stimulus generation, failure analysis, coverage analysis, and coverage closure.
• Strong debug skills and the ability to translate architectural intent into an effective verification strategy and execution plan.
• Strong software and scripting fundamentals for building scalable DV infrastructure, automation, and analysis workflows.
• 8+ years of direct experience in memory management verification.
• Seasoned developer using object-oriented programming principles.

Preferred Qualifications

• Experience verifying advanced frontend architectures or decoupled fetch/prediction pipelines in high-performance CPU cores.
• Experience with branch prediction microarchitecture such as BTB-style structures, target prediction, return prediction, global-history-based prediction, predictor training, and misprediction recovery.
• Experience using formal verification to target bounded, control-heavy, or interface-sensitive frontend problems.
• Experience using emulation or other acceleration techniques to improve turnaround on large CPU verification workloads.
• Experience collaborating across architecture, performance, compiler, system verification, and software teams to close verification gaps from multiple perspectives.
• Demonstrated technical leadership through mentoring, methodology influence, and cross-team execution on complex CPU verification efforts.

What Success Looks Like

• Frontend verification plans capture real architectural and microarchitectural risks early and completely.
• Difficult branch prediction, fetch, redirect, and recovery bugs are found early, debugged efficiently, and closed with durable solutions.
• Verification quality improves across the broader CPU DV organization through stronger methodology, reusable infrastructure, and clear technical leadership.
• Architecture, design, and DV teams rely on this engineer to solve the most complex frontend verification challenges in high-performance CPU development.

Benefits

In addition to base pay, this role may be eligible for variable/incentive compensation and/or equity. It also includes a comprehensive, competitive benefits package which may include healthcare and retirement plans, paid time off, and more.