[llvm] [LLVM][CodeGen][SVE] Add isel patterns for abs-diff partial reductions. (PR #212800)

[Ricardo Jesus via llvm-commits]

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@@ -4215,6 +4215,20 @@ let Predicates = [HasSVE2_or_SME] in {
   defm UABALB_ZZZ : sve2_int_absdiff_accum_long<0b10, "uabalb", int_aarch64_sve_uabalb>;
   defm UABALT_ZZZ : sve2_int_absdiff_accum_long<0b11, "uabalt", int_aarch64_sve_uabalt>;
 
+  def : Pat<(nxv8i16 (partial_reduce_umla nxv8i16:$Acc, (AArch64sabd_p (SVEAnyPredicate), nxv16i8:$Op1, nxv16i8:$Op2), (nxv16i8 (splat_vector (i32 1))))),
+            (SABALT_ZZZ_H (SABALB_ZZZ_H $Acc, $Op1, $Op2), $Op1, $Op2)>;
+  def : Pat<(nxv4i32 (partial_reduce_umla nxv4i32:$Acc, (AArch64sabd_p (SVEAnyPredicate), nxv8i16:$Op1, nxv8i16:$Op2), (nxv8i16 (splat_vector (i32 1))))),
+            (SABALT_ZZZ_S (SABALB_ZZZ_S $Acc, $Op1, $Op2), $Op1, $Op2)>;
+  def : Pat<(nxv2i64 (partial_reduce_umla nxv2i64:$Acc, (AArch64sabd_p (SVEAnyPredicate), nxv4i32:$Op1, nxv4i32:$Op2), (nxv4i32 (splat_vector (i32 1))))),
+            (SABALT_ZZZ_D (SABALB_ZZZ_D $Acc, $Op1, $Op2), $Op1, $Op2)>;
+
+  def : Pat<(nxv8i16 (partial_reduce_umla nxv8i16:$Acc, (AArch64uabd_p (SVEAnyPredicate), nxv16i8:$Op1, nxv16i8:$Op2), (nxv16i8 (splat_vector (i32 1))))),
+            (UABALT_ZZZ_H (UABALB_ZZZ_H $Acc, $Op1, $Op2), $Op1, $Op2)>;
+  def : Pat<(nxv4i32 (partial_reduce_umla nxv4i32:$Acc, (AArch64uabd_p (SVEAnyPredicate), nxv8i16:$Op1, nxv8i16:$Op2), (nxv8i16 (splat_vector (i32 1))))),
+            (UABALT_ZZZ_S (UABALB_ZZZ_S $Acc, $Op1, $Op2), $Op1, $Op2)>;
+  def : Pat<(nxv2i64 (partial_reduce_umla nxv2i64:$Acc, (AArch64uabd_p (SVEAnyPredicate), nxv4i32:$Op1, nxv4i32:$Op2), (nxv4i32 (splat_vector (i32 1))))),
+            (UABALT_ZZZ_D (UABALB_ZZZ_D $Acc, $Op1, $Op2), $Op1, $Op2)>;
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rj-jesus wrote:

Thank you for looking into it, and apologies for bringing it up late - the new code only came up recently when looking at other widening reductions.

https://github.com/llvm/llvm-project/pull/212800