I want to write a pattern that looks something like this:
def : Pat<(unalignedstore (v2f64 VR128:$src), addr:$dst),
(MOVSDmr ADD64ri8(addr:$dst, imm:8), ( SHUFPDrri (VR128:$src,
(MOVSDmr addr:$dst, FR64:$src))), imm:3)
So I want to convert an unaligned vector store to a scalar store, a shuffle
and a scalar store.
There are several question I have:
- Is the imm:3 syntax correct? Basically I want to hard-code the shuffle mask
- The first MOVSD doesn't really "feed" the SHUFPD. How do I
write the
pattern to guarantee the MOVSD happens before the SHUFPD when the scheduler
does its thing?
- How do I hard-code the immediate add that updates the store address for the
high element? Again, I don't think imm:8 is right.
Is it possible to express this kind of thing in tblgen or do I have to write
custom code?
-Dave
On Monday 17 November 2008 14:28, David Greene wrote:> I want to write a pattern that looks something like this: > > def : Pat<(unalignedstore (v2f64 VR128:$src), addr:$dst), > (MOVSDmr ADD64ri8(addr:$dst, imm:8), ( SHUFPDrri (VR128:$src, > (MOVSDmr addr:$dst, FR64:$src))), imm:3) > > So I want to convert an unaligned vector store to a scalar store, a shuffle > and a scalar store.I got a little further with this: def : Pat<(unalignedstore (v2f64 VR128:$src), addr:$dst), (MOVSDmr (ADD64ri8 (LEA64r addr:$dst), 8), (MOVPD2SDrr (SHUFPDrri (v2f64 VR128:$src), (v2f64 VR128:$src), 3)), (MOVSDmr addr:$dst, FR64: $src))>; Now tblgen (rightly) complains about MOVSDmr having too many operands. How do I specify the dependency MOVSD->SHUFPD->MOVSD? I'm a little nervous about the extra MOVPD2SDrr. It exists only to get the t typing correct. I tried forcing the output of the SHUFPD to be typed f64 but I couldn't get anything to work. As an alternative I could write a special MOVSDrr pattern that accepts a v2f64. I'm hoping the MOVPD2SDrr will just be coalesced away. The bare "3" and "8" seem to be accepted. So the only remaining problem is how to specify the dependencies. Is there an example in another target that does this sort of thing? -Dave
On Nov 17, 2008, at 3:50 PM, David Greene wrote:> On Monday 17 November 2008 14:28, David Greene wrote: >> I want to write a pattern that looks something like this: >> >> def : Pat<(unalignedstore (v2f64 VR128:$src), addr:$dst), >> (MOVSDmr ADD64ri8(addr:$dst, imm:8), ( SHUFPDrri >> (VR128:$src, >> (MOVSDmr addr:$dst, FR64:$src))), imm:3) >> >> So I want to convert an unaligned vector store to a scalar store, a >> shuffle >> and a scalar store. > > I got a little further with this: > > def : Pat<(unalignedstore (v2f64 VR128:$src), addr:$dst), > (MOVSDmr (ADD64ri8 (LEA64r addr:$dst), 8), (MOVPD2SDrr > (SHUFPDrri > (v2f64 VR128:$src), (v2f64 VR128:$src), 3)), (MOVSDmr addr:$dst, FR64: > $src))>; > > Now tblgen (rightly) complains about MOVSDmr having too many > operands. How do > I specify the dependency MOVSD->SHUFPD->MOVSD? > > I'm a little nervous about the extra MOVPD2SDrr. It exists only to > get the t > typing correct. I tried forcing the output of the SHUFPD to be > typed f64 but > I couldn't get anything to work. As an alternative I could write a > special > MOVSDrr pattern that accepts a v2f64. I'm hoping the MOVPD2SDrr will > just be coalesced away. > > The bare "3" and "8" seem to be accepted. > > So the only remaining problem is how to specify the dependencies. > Is there an > example in another target that does this sort of thing?No, there is currently no way to refer to the chain result of a node in a pattern. Patches welcome :-). Dan