llvm dev - Aug 2013 - [LLVMdev] unique id for a llvm Instruction‏

what if another pointer points to the same instruction?
 Is this possible to happen?

Eirini
 		 	   		  
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>
>
> what if another pointer points to the same instruction?
>
You can have many pointers to the same instruction. However, the address in
memory where that instruction lives is unique. Instruction pointers (or
Value pointers) are thus commonly used as keys in hash tables or similar.
Instructions or Values are almost never copied, so that you won't find the
same instruction at different addresses in memory.

Jonas


On Thu, Aug 29, 2013 at 2:57 PM, Eirini Psallida <eirini_dit at
windowslive.com
> wrote:
>  what if another pointer points to the same instruction?
> Is this possible to happen?
>
> Eirini
>
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On 8/29/2013 8:45 AM, Jonas Wagner wrote:
>
> You can have many pointers to the same instruction. However, the address
> in memory where that instruction lives is unique. Instruction pointers
> (or Value pointers) are thus commonly used as keys in hash tables or
> similar. Instructions or Values are almost never copied, so that you
> won't find the same instruction at different addresses in memory.
There can be a "reverse" situation: if an instruction is deleted, and 
another one is created, it can get the same address.

-K

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