Method optimize_load_global_push_null

crates/codegen/src/ir.rs:1428–1452

LOAD_GLOBAL + PUSH_NULL -> LOAD_GLOBAL , NOP

(&mut self)

    /// LOAD_GLOBAL <even> + PUSH_NULL -> LOAD_GLOBAL <odd>, NOP
    fn optimize_load_global_push_null(&mut self) {
        for block in &mut self.blocks {
            let mut i = 0;
            while i + 1 < block.instructions.len() {
                let curr = &block.instructions[i];
                let next = &block.instructions[i + 1];

                let (Some(Instruction::LoadGlobal { .. }), Some(Instruction::PushNull)) =
                    (curr.instr.real(), next.instr.real())
                else {
                    i += 1;
                    continue;
                };

                let oparg = u32::from(block.instructions[i].arg);
                if (oparg & 1) != 0 {
                    i += 1;
                    continue;
                }

                block.instructions[i].arg = OpArg::new(oparg | 1);
                block.instructions.remove(i + 1);
            }
        }
    }

    /// Convert LOAD_CONST for small integers to LOAD_SMALL_INT
    /// maybe_instr_make_load_smallint