Module stack 

Pass 5: Stack Lower – converts ANF IR to Stack IR.

The fundamental challenge: ANF uses named temporaries but Bitcoin Script operates on an anonymous stack. We maintain a “stack map” that tracks which named value lives at which stack position, then emit PICK/ROLL/DUP operations to shuttle values to the top when they are needed.

This matches the TypeScript reference compiler and aligned Go compiler:

• Private methods are inlined at call sites rather than compiled separately
• Constructor is skipped
• @ref: aliases are handled via PICK (non-consuming copy)
• @this is a compile-time placeholder (push 0)
• super() is a no-op at stack level

Structs

StackMethod

A stack-lowered method.

Enums

PushValue

Typed value for push operations.

StackOp

A single stack-machine operation.

Functions

lower_to_stack

Lower an ANF program to Stack IR. Private methods are inlined at call sites rather than compiled separately. The constructor is skipped since it’s not emitted to Bitcoin Script.