-opt

Specifies code optimization options to apply to object code.

  -optkeyword [,...]   

The keyword arguments are:

off | none

Suppresses all optimizations. This is the default.

  on   

Same as -opt level=2

  all | full   

Same as -opt speed,level=2

  l[evel]=num  

Sets a specific optimization level. The options for num are:

• 0 - Suppress all optimizations
• 1 - High Level Optimizations, Branch Optimization
• 2 - Constant Propagation, Copy Propagation, Dead Code Elimination, Register Allocation, Peephole, Common Subexpression Elimination, Branch Tail Merge
• 3 - Constant Propagation, Copy Propagation, Dead Code Elimination, Register Allocation, Peephole, Common Subexpression Elimination, Branch Tail Merge

For num options 0 through 3 inclusive, the default is 0.

  [no]space   

Optimizes object code for size. Equivalent to #pragma optimize_for_size on.

  [no]speed   

Optimizes object code for speed. Equivalent to #pragma optimize_for_size off.

  [no]cse | [no]commonsubs   

Common subexpression elimination. Equivalent to #pragma opt_common_subs.

  [no]deadcode   

Removes dead code. Equivalent to #pragma opt_dead_code.

  [no]deadstore   

Removes dead assignments. Equivalent to #pragma opt_dead_assignments.

  [no]lifetimes   

Computes variable lifetimes. Equivalent to #pragma opt_lifetimes.

  [no]loop[invariants]   

Removes loop invariants. Equivalent to #pragma opt_loop_invariants.

  [no]prop[agation]   

Propagation of constant and copy assignments. Equivalent to #pragma opt_propagation.

  [no]strength   

Strength reduction. Reducing multiplication by an array index variable to addition. Equivalent to #pragma opt_strength_reduction.

  [no]dead   

Same as -opt [no]deadcode and [no]deadstore. Equivalent to #pragma opt_dead_code on|off and #pragma opt_dead_assignments.

  display | dump   

Displays complete list of active optimizations.