Compiler Optimization

The optimizer is a tool for improving performance and reducing resource consumption. In this context, the terms performance and resource can apply across multiple dimensions, including but not limited to: compiled code size, scratch slot usage, opcode cost, etc.

Optimizer Usage

The compiler determines which optimizations to apply based on the provided OptimizeOptions object as shown in the code block below. Both compileTeal as well as the Router.compile_program method can receive an optimize parameter of type OptimizeOptions.

# optimize scratch slots for all program versions (shown is version 4)
optimize_options = OptimizeOptions(scratch_slots=True)
compileTeal(approval_program(), mode=Mode.Application, version=4, optimize=optimize_options)

Optimization Flag	Description	Default
scratch_slots	A boolean describing whether or not scratch slot optimization should be applied.	False

Default Behavior

The OptimizeOptions constructor receives keyword arguments representing flags for particular optimizations. If an argument is not provided to the constructor of OptimizeOptions, a default program version dependent optimization behavior is used in its place according to the table below.

Optimization Flag	Value	Interpretation	Program Version	Behavior
scratch_slots	None	Default	≥ 9	Scratch slot optimization is applied
	None	Default	≤ 8	Scratch slot optimization is not applied
	True	Enable	any	Scratch slot optimization is applied
	False	Disable	any	Scratch slot optimization is not applied
frame_pointers	None	Default	≥ 8	Frame pointers available and are therefore applied
	None	Default	≤ 7	Frame pointers not available and not applied
	True	Enable	≥ 8	Frame pointers available and applied
	True	attempt	≤ 7	An error occurs when attempting to compile as frame pointers are not available
	False	Disable	any	Frame pointers not applied

When the optimize parameter is omitted in compileTeal or Router.compile_program, all parameters conform to program version dependent defaults as defined in the above table. For example:

# apply default optimization behavior by NOT providing `OptimizeOptions`
# for version 9 as shown next, this is equivalent to passing in
# optimize=OptimizeOptions(scratch_slots=True, frame_pointers=True)

compileTeal(approval_program(), mode=Mode.Application, version=9)

# for version 8 as shown next, this is equivalent to passing in
# optimize=OptimizeOptions(scratch_slots=False, frame_pointers=True)

compileTeal(approval_program(), mode=Mode.Application, version=8)