llvm dev - Apr 2015 - [LLVMdev] want to intercept array dereferences

Normally for int n unknown at static time, "a[n]" and
"*(a+n)" results
in an add and then a dereference.  I want instead for it to compile to
a system call that takes two arguments, a and n.  Where should I
intercept this in LLVM?

Gry

Far too late. That would need to be in Clang.

On Wed, Apr 8, 2015 at 5:36 PM, Gry Gunvor <gry.gunvor at gmail.com>
wrote:
> Normally for int n unknown at static time, "a[n]" and
"*(a+n)" results
> in an add and then a dereference.  I want instead for it to compile to
> a system call that takes two arguments, a and n.  Where should I
> intercept this in LLVM?
>
> Gry
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> LLVM Developers mailing list
> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
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If I understand correctly, LLVM is a *typed* assembly language.  Could
I just look for a pointer type plus an integer type followed by a
dereference?  That would catch both a[n] and *(a+n).
Gry


On Tue, Apr 7, 2015 at 10:46 PM, Bruce Hoult <bruce at hoult.org>
wrote:
> Far too late. That would need to be in Clang.
>
> On Wed, Apr 8, 2015 at 5:36 PM, Gry Gunvor <gry.gunvor at gmail.com>
wrote:
>>
>> Normally for int n unknown at static time, "a[n]" and
"*(a+n)" results
>> in an add and then a dereference.  I want instead for it to compile to
>> a system call that takes two arguments, a and n.  Where should I
>> intercept this in LLVM?
>>
>> Gry
>> _______________________________________________
>> LLVM Developers mailing list
>> LLVMdev at cs.uiuc.edu         http://llvm.cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev
>
>