Re: GIMPLE tuples document uploaded to wiki

[Jan Hubicka <hubicka at ucw dot cz>]

> 
> I have added the design document and links to most of the discussions
> we've had so far.  Aldy updated the document to reflect the latest thread.
> 
> http://gcc.gnu.org/wiki/tuples

Looks great, still I think "locus" and "block" could be both merged into
single integer, like RTL land has INSN_LOCATOR.
After gimplification, only place where we are modifying blocks but not
locators is inliner.  While doing the gimplification, we probably can
keep track of line numbers and blocks in parallel.

Also ssa_operands structures should be somewhere in the header and uid
would be handy for on-side datastructures.

In CFG  getting rid of labels in GS_COND woulsd actually save us
noticeable amount of memory by avoiding the need for labels.  Perhaps we
can simply define "true branch target"/"false branch target" to point to
label or BB depending on CFG presence or to be NULL after CFG conversion
and rely on CFG edges. GS_SWITCH would be harder, since association with
CFG edges is not so direct.

Honza