[LLVMdev] nosegmentedstacks function attribute

[Joerg Sonnenberger]

On Sat, Feb 04, 2012 at 09:57:29AM +0100, Duncan Sands wrote:
> Hi Sanjoy,
> 
> > Now that LLVM has support for a larger attribute set, I think it is a
> > good idea to add one that stops LLVM from generating segmented stacked
> > version of a function.
> 
> why?  If some functions have segmented stacks, don't all functions called
> by it need segmented stacks too?

No, the check for stack usage can be lifted. E.g. if you have the call
graph

A -- B -- C 
  \- D -/

B can require the stack space for B, D and C and call the non-checking
versions of them.

Joerg