[LLVMdev] how to code a loop in llvm assembly

[Simon Burton]

Hi,

I've read over the "LLVM Language Reference Manual"
a few times, and writing some ll code, but i'm stuck at
a very basic point. How to decrement a counter variable ?

int %count(int %n) {
EntryBlock:
  %cond = seteq int %n, 0
  br bool %cond, label %Exit, label %Next
Next:
; how to decrement n ?
  %new_n = sub int %n, 1
  br label %EntryBlock
Exit:
  ret int 0
}

I guess I could malloc a variable and use store/load. Is that the right way ?

Also the above code is invalid:
Entry block to function must not have predecessors!
label %EntryBlock
Broken module found, compilation aborted!

thanks for any hints,

Simon.

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Simon Burton, B.Sc.
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