Displaying 2 results from an estimated 2 matches for "truncate_i16_to_i8".
2007 Apr 23
0
[LLVMdev] Register based vector insert/extract
...L = ADDi8 CL, 42
In your case, you'd define your vector register class with 4 subregs, one
for each piece.
Unfortunately, none of this exists yet :(. To handle truncates and
extends on X86, we currently emulate this by generating machineinstrs
like:
r1024 = X86_LOADi16 ...
r1025 = TRUNCATE_i16_to_i8 r1024
r1026 = ADDi8 r1025, 42
In the asmprinter, we print TRUNCATE_i16_to_i8 as a commented out noop if
the register allocator happens to allocate 1024 and 1025 to the same
register. If not, it uses an asmprinter hack to print this as a copy
instruction. This is horrible, and doesn't p...
2007 Apr 23
2
[LLVMdev] Register based vector insert/extract
On Apr 23, 2007, at 1:43 PM, Christopher Lamb wrote:
> On Apr 23, 2007, at 1:17 PM, Christopher Lamb wrote:
>
>> On Apr 23, 2007, at 12:31 PM, Chris Lattner wrote:
>>
>>> On Mon, 23 Apr 2007, Christopher Lamb wrote:
>>>> How can one let the back end know how to insert and extract
>>>> elements of
>>>> a vector through sub-register