[LLVMdev] ptrtoint

[reed kotler]

Technically I don't need C/C++ code for it.

I'm not really very good at writing LLVM assembly code by hand
(but I should be - lol ).

I'm working on fast-isel and I want to have executable tests for all of this
and not just make check tests.

It's easier for me to do that in C/C++ and then save the .ll and morph 
it into
a make check test.

I'm going through the fast-isel tests for x86 now and adapting them for 
Mips.
(will do the same for AArch64 and other ports).

I want an executable variant for all of them.

On 09/29/2014 03:11 PM, Duncan P. N. Exon Smith wrote:
>> On Sep 29, 2014, at 2:29 PM, reed kotler <rkotler at mips.com> wrote:
>>
>> Thanks.
>>
>> So what about a fragment like this: (taken from fast-isel.ll in X86 )
>>
>> define void @ptrtoint_i1(i8* %p, i1* %q) nounwind {
>>   %t = ptrtoint i8* %p to i1
>>   store i1 %t, i1* %q
>>   ret void
>> }
> Intuitively, this looks like:
>
>      void ptrtoint_i1(char *p, bool *q) { *q = (bool)p; }
>
> However, `q` needs to be addressable in C/C++, so it's left as an `i8`.
>
> `git log` suggests this particular testcase evolved incrementally out
> of hand-written IR.
>
> Why do you need C/C++ code for it?  Just interested?
>
>> TIA.
>>
>> On 09/29/2014 02:16 PM, Duncan P. N. Exon Smith wrote:
>>>> On Sep 29, 2014, at 1:51 PM, reed kotler <rkotler at mips.com> wrote:
>>>>
>>>> What kind of C or C++ code will emit a "ptrtoint" op?
>>> This C code:
>>>
>>>      long ptrtoint(void *p) { return (long)p; }
>>>
>>> gives:
>>>
>>>      define i64 @ptrtoint(i8* %p) {
>>>        %1 = ptrtoint i8* %p to i64
>>>        ret i64 %1
>>>      }
>>>
>>>
>>>> Also, what causes i1 to be emitted?
>>> This C++ code:
>>>
>>>      bool i1() { return false; }
>>>
>>> gives:
>>>
>>>      define zeroext i1 @_Z2i1v() {
>>>        ret i1 false
>>>      }
>>>
>>>
>>>> Tia.
>>>>
>>>> Reed
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