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Alive: Automatic LLVM's Instcombine Verifier

Alive is a tool that can prove the correctness of InstCombine optimizations specified in a high-level language.

NOTE: Alive is in maintenance mode; no new features are planned. Please try Alive2 instead.


Alive requires Python 2.7.x and Z3 4.3.2 (or later), which can be obtained from (use the unstable branch)


./ file.opt

The 'tests' directory has multiple examples of optimizations.

More Information

Please see this paper for more details about Alive:

Online Version

Alive is also available online at:

Generating Benchmarks

Alive will automatically generate benchmarks in SMT-LIB 2 format when the 'bench' directory exists and when python is run in non-optimized mode (the default). These benchmarks are over the bit-vector theory and may or may not have quantifiers.