Skip to the selected question
ASIC.FYI

ASIC Interview Question Bank

1,000+ hardware interview questions.Curated and reviewed by industry engineers.1,000+ hardware questions1,000+ questionsEngineer-reviewed
Question bank1110 results
  1. Easy
  2. Easy
  3. Medium
  4. Medium
  5. Medium
  6. Hard
  7. Medium
  8. Medium
  9. Medium
  10. Medium
  11. Medium
  12. Medium
  13. Medium
  14. Medium
  15. Hard
  16. Medium
  17. Easy
  18. Easy
  19. Medium
  20. Medium
  21. Medium
  22. Hard
  23. Medium
  24. Medium
  25. Easy
  26. Medium
  27. Medium
  28. Medium
  29. Medium
  30. Medium
  31. Medium
  32. Medium
  33. Medium
  34. Hard
  35. Medium
  36. Hard
  37. Medium
  38. Hard
  39. Hard
  40. Medium
  41. Medium
  42. Medium
  43. Hard
  44. Hard
  45. Hard
  46. Medium
  47. Medium
  48. Hard
  49. Medium
  50. Medium
DescriptionQ178
Page ↗
Q178DVArchFollow-up to Q867ASIC interview problem

Release reordered responses in request order

TechniquesScoreboardReorder bufferIn-order retirement
DifficultyHard
TopicReference Models
LanguageSystemVerilog
Requirements4 checkpoints
01

Problem

Responses may arrive out of order, but completed transactions must be emitted downstream in original global request order.

Function headerSystemVerilog
function void on_req(int id, longint addr);
function bit on_rsp(int id);
function void drain_ready(ref longint released[$]);

Example input and output

Use this case to check your interpretation
Input
global requests A(id1),B(id2),C(id1); responses arrive for id2 then id1
Output
after id2 response emit []; after id1 response emit [A,B]; C remains pending
Explanation

B is complete but blocked behind A in global order; completing A releases the longest completed prefix without retiring C.

02

Requirements (4)

  • Record global request order across all IDs.
  • Assume responses remain FIFO within each ID.
  • Mark a request complete without immediately removing it from global order.
  • Emit and retire only the longest completed prefix.