Constant Propagation Transformation: Replacing Variables with Constant Values

Part of our transformation series in emmtrix Studio

What is Constant Propagation?
An optimization that replaces variables with known constant values at compile time. Expressions containing only constants or previously propagated values are pre-evaluated and simplified.

Why use Constant Propagation?

▪️ Reduces runtime computations
▪️ Simplifies code
▪️ Improves dependency analysis and enables further optimizations

Key Parameters

• global: propagate across functions
• modify_nonstatic_functions: affects non-static functions (use with care)
• remove_dead_blocks: eliminates unreachable code

Example
The image below shows a simple before/after comparison. Constant values are propagated, and expressions are pre-computed during compilation.

Already posted articles:

• Loop Unrolling
• Loop Interchange
• Bitblast Transformation
• Pointer Resolve Transformation