[LLVMdev] Is bitcast now needed in LLVM?

[James Molloy]

Hi,

sitofp has different semantics to bitcast. "bitcast i32 %a to float" would
not do int-to-float conversion, but would perform the equivalent of "f =
*&i;".

Also, bitcast is still not a no-op in AArch64 big endian - we have to do
vector shuffling still.

Cheers,

James

On Fri, 17 Apr 2015 at 09:14 Dave Pitsbawn <dpitsbawn at gmail.com> wrote:

> I always thought that bitcast was a no-op internal llvm thing to fit the
> IR type system.
>
> I currently use sitofp, but I see your point.
>
> On Fri, Apr 17, 2015 at 1:04 AM, James Molloy <james at jamesmolloy.co.uk>
> wrote:
>
>> Hi Dave,
>>
>> You can still bitcast between i32 and float, for example.
>>
>> Cheers,
>>
>> James
>>
>> On Fri, 17 Apr 2015 at 09:03 Dave Pitsbawn <dpitsbawn at gmail.com> wrote:
>>
>>> Seems like a new change in LLVM has made it so that bitcast of bitcast
>>> i8* %1 to %Foo* meaningless?
>>>
>>> If I'm correct is there any need for the bitcast anymore?
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>>
>
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