Issues

• Opt fails to eliminate redundant negated terms implied by mutually exclusive comparisons across a muxed operand

  optimizer
  Bug

  google/xls#5152 · Filter by author mikex-oss opened on Oct 15, 2026
  3

• opt fails to propagate non-absorbing or/and sibling conditions into operand fanin

  optimizer
  Bug

  google/xls#5151 · Filter by author mikex-oss opened on Oct 15, 2026

• opt_main fails to apply boolean/bitwise absorption (a & b) | a | ... => a | ... in n-ary |/& expressions

  optimizer
  Bug

  google/xls#5120 · Filter by author mikex-oss opened on Oct 12, 2026
  1

• ir_equivalence failure after resource_sharing over multiple nested branches

  bugoptimizer
  google/xls#4941 · Filter by author proppy opened on Sep 9, 2026
  1

• opt_main times out in PartialInfoQueryEngine / IntervalSet::Combine during select_simp

  bugfuzzoptimizer
  google/xls#4425 · Filter by author proppy opened on Jun 17, 2026

• Possible optimization memory issue, crasher_2026-04-03_4e72

  bugoptimizer
  google/xls#4044 · Filter by author mikex-oss opened on Apr 3, 2026
  1

• Array-slice miscompile (bad optimization)

  optimizer
  google/xls#2783 · Filter by author ericastor opened on Aug 6, 2025
  5

  

• [enhancement][opt] Fuse sign_ext(carry) + add + literal(1) into a single carry‑in adder

  enhancementoptimizer
  google/xls#2045 · Filter by author cdleary opened on Apr 21, 2025
  2

• [enhancement][long-term] Quickcheck proofs that can be leveraged by the optimizer

  enhancementformallong-term-enhancementoptimizer
  google/xls#2025 · Filter by author cdleary opened on Mar 31, 2025
  2

• Inter-proc channel operations where data is ignored

  codegenoptimizer🧦 soxstitching
  google/xls#1928 · Filter by author grebe opened on Feb 13, 2025

• [idea] For exhaustive matches, should we expose the construct to the IR?

  irlong-term-enhancementoptimizer
  google/xls#1920 · Filter by author cdleary opened on Feb 9, 2025
  2

• [enhancement] Make invoke side-effecting + make a "safe to remove side-effecting op" category

  enhancementoptimizer
  google/xls#1806 · Filter by author grebe opened on Dec 19, 2024

• Hoist operations above selects if it enables constant folding

  optimizer
  google/xls#1611 · Filter by author meheff opened on Sep 18, 2024

• Flatten arrays in proc state

  optimizerscheduler
  google/xls#1489 · Filter by author grebe opened on Jun 18, 2024
  

• [enhancement] missed optimization opportunity for duplicated logic in sel branches

  enhancementoptimizer
  google/xls#1482 · Filter by author proppy opened on Jun 14, 2024

• Assignments with if statements are not optimized

  optimizer
  google/xls#1475 · Filter by author m-torhan opened on Jun 12, 2024

• Missing priority select optimizations

  optimizer
  google/xls#1446 · Filter by author grebe opened on May 31, 2024

• [enhancement] User-specified dead_if(predicate) akin to assume(predicate) to enable clock gating

  codegenenhancementoptimizerscheduler
  google/xls#1360 · Filter by author cdleary opened on Mar 27, 2024
  1

• Look through array definition used to implement "recursive functions"

  dslxiroptimizer
  google/xls#1357 · Filter by author hongted opened on Mar 26, 2024
  1

  

• Switch range analysis to using LeafTypeTreeViews

  iroptimizer
  google/xls#1334 · Filter by author meheff opened on Mar 6, 2024

• Optimization opportunity: shift width with as result of +/- operation with constant could eliminate the add operation.

  optimizer
  google/xls#1274 · Filter by author hzeller opened on Jan 23, 2024

• [Want Test]: Good to have an integration test that can see the difference between some passes being run to fixed-point and run only once

  optimizertesting
  google/xls#1245 · Filter by author allight opened on Jan 4, 2024

• Optimization opportunity avoiding zero-expansion for single bit manipulation ?

  optimizer
  google/xls#1217 · Filter by author hzeller opened on Dec 5, 2023
  1

• Missed optimization: one_hot(decode()) only optimizes for partial-width decode

  enhancementoptimizer
  google/xls#1186 · Filter by author ericastor opened on Nov 8, 2023

• [codegen] Opportunistically make names into the originals from the user input program

  codegeniroptimizer
  google/xls#1121 · Filter by author cdleary opened on Aug 29, 2023