SSA and implicit uses.

[Sanjiv Kumar Gupta]

For statements like;
  a = 0;
  a++;
  a++;

My compiler generates SSA form like below:
  r200 = 0;
  r201 = r200 + 1;
  r202 = r201 + 1;

now all of r200, r201 and r202 are independent live
ranges and may get assigned different hard regs.
How can I use the m/c insns like "incr hardreg" in a
situation like this?

Do I need to generate "mov" insns before "incr"
and then get rid of them by peephole or coalescing?

How this situation is dealt with in GCC?

Thanks for any pointers.

--Sanjiv
  
  




		
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