Flatten is an optimization pass for the SSA IntermediateLanguage, invoked from SSASimplify.

Description

This pass flattens arguments to SSA constructors, blocks, and functions.

If a tuple is explicitly available at all uses of a function (resp. block), then:

• The formals and call sites are changed so that the components of the tuple are passed.

• The tuple is reconstructed at the beginning of the body of the function (resp. block).

Similarly, if a tuple is explicitly available at all uses of a constructor, then:

• The constructor argument datatype is changed to flatten the tuple type.

• The tuple is passed flat at each ConApp.

• The tuple is reconstructed at each Case transfer target.

Implementation

flatten.sig flatten.fun

Details and Notes