Module llhd::opt::uvd

Unused value deletion.

This optimization pass removes all instructions whose value is never used.

Algorithm

• Iterate over every instruction. If the instruction has no users, add it to the set of pending removals.
• Pop the next instruction off the set and remove it from its parent.
• For every operand to the instruction, if it has no users, add it to the set of pending removals.
• Repeat until the set becomes empty.