Jason Merrill wrote: > Jan Hubicka wrote: >> Thanks for explanation - the space optimization seems relatively >> chalenging to implement, in particular because the variables in scope >> might change in between the time abstract copy is output and the time >> the block referencing to the block via abstract pointer is output. > > The block is a lexical thing, optimizations don't change that. > >> We have origin pointers in declarations and origin pointers in blocks. >> I guess optimization willing to know all variables same from user POV >> (for lets say setting watchpoint on something in inline function) >> probably cares about origins of declarations rather than blocks. >> At what time the blocks actually matters? > > So the debugger knows which declarations are in scope at a particular PC. > >> For example if I have block that contians just single block and declare >> no new variables, can I simply remove it and replace it by the inner >> block? > > Yes. > Two more general questions 1) if i have a block A with several children C1...Cn and A does not declare any variable, can i remove A and have C1...Cn point to A's parent.
2) can you remove leaf blocks that have no declarations? > Jason >
