[PATCH] D111996: [SVE] Fix selection failure when splitting extended masked loads

[Kerry McLaughlin via Phabricator via llvm-commits]

kmclaughlin created this revision.
kmclaughlin added reviewers: sdesmalen, david-arm, aartbik, craig.topper.
Herald added subscribers: psnobl, hiraditya, tschuett.
Herald added a reviewer: efriedma.
kmclaughlin requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

When splitting a masked load, `GetDependentSplitDestVTs` is used to get the
MemVTs of the high and low parts. If the masked load is extended, this
may return VTs with different element types which are used to create the
high & low masked load instructions.
This patch changes `GetDependentSplitDestVTs` to ensure we return VTs with
the same element type.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D111996

Files:
  llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
  llvm/test/CodeGen/AArch64/sve-masked-ldst-sext.ll
  llvm/test/CodeGen/AArch64/sve-masked-ldst-zext.ll


Index: llvm/test/CodeGen/AArch64/sve-masked-ldst-zext.ll
===================================================================
--- llvm/test/CodeGen/AArch64/sve-masked-ldst-zext.ll
+++ llvm/test/CodeGen/AArch64/sve-masked-ldst-zext.ll
@@ -76,9 +76,29 @@
   ret <vscale x 2 x i64> %ext
 }
 
+; Return type requires splitting
+define <vscale x 8 x i64> @masked_zload_nxv8i16(<vscale x 8 x i16>* %a, <vscale x 8 x i1> %mask) {
+; CHECK-LABEL: masked_zload_nxv8i16:
+; CHECK:       punpklo p1.h, p0.b
+; CHECK-NEXT:  punpkhi p0.h, p0.b
+; CHECK-NEXT:  punpklo p2.h, p1.b
+; CHECK-NEXT:  punpkhi p1.h, p1.b
+; CHECK-NEXT:  ld1h { z0.d }, p2/z, [x0]
+; CHECK-NEXT:  punpklo p2.h, p0.b
+; CHECK-NEXT:  punpkhi p0.h, p0.b
+; CHECK-NEXT:  ld1h { z1.d }, p1/z, [x0, #1, mul vl]
+; CHECK-NEXT:  ld1h { z2.d }, p2/z, [x0, #2, mul vl]
+; CHECK-NEXT:  ld1h { z3.d }, p0/z, [x0, #3, mul vl]
+; CHECK-NEXT:  ret
+  %load = call <vscale x 8 x i16> @llvm.masked.load.nxv8i16(<vscale x 8 x i16>* %a, i32 2, <vscale x 8 x i1> %mask, <vscale x 8 x i16> undef)
+  %ext = zext <vscale x 8 x i16> %load to <vscale x 8 x i64>
+  ret <vscale x 8 x i64> %ext
+}
+
 declare <vscale x 2 x i8> @llvm.masked.load.nxv2i8(<vscale x 2 x i8>*, i32, <vscale x 2 x i1>, <vscale x 2 x i8>)
 declare <vscale x 2 x i16> @llvm.masked.load.nxv2i16(<vscale x 2 x i16>*, i32, <vscale x 2 x i1>, <vscale x 2 x i16>)
 declare <vscale x 2 x i32> @llvm.masked.load.nxv2i32(<vscale x 2 x i32>*, i32, <vscale x 2 x i1>, <vscale x 2 x i32>)
 declare <vscale x 4 x i8> @llvm.masked.load.nxv4i8(<vscale x 4 x i8>*, i32, <vscale x 4 x i1>, <vscale x 4 x i8>)
 declare <vscale x 4 x i16> @llvm.masked.load.nxv4i16(<vscale x 4 x i16>*, i32, <vscale x 4 x i1>, <vscale x 4 x i16>)
 declare <vscale x 8 x i8> @llvm.masked.load.nxv8i8(<vscale x 8 x i8>*, i32, <vscale x 8 x i1>, <vscale x 8 x i8>)
+declare <vscale x 8 x i16> @llvm.masked.load.nxv8i16(<vscale x 8 x i16>*, i32, <vscale x 8 x i1>, <vscale x 8 x i16>)
Index: llvm/test/CodeGen/AArch64/sve-masked-ldst-sext.ll
===================================================================
--- llvm/test/CodeGen/AArch64/sve-masked-ldst-sext.ll
+++ llvm/test/CodeGen/AArch64/sve-masked-ldst-sext.ll
@@ -70,9 +70,29 @@
   ret <vscale x 2 x i64> %ext
 }
 
+; Return type requires splitting
+define <vscale x 16 x i32> @masked_sload_nxv16i8(<vscale x 16 x i8>* %a, <vscale x 16 x i1> %mask) {
+; CHECK-LABEL: masked_sload_nxv16i8:
+; CHECK:         punpklo p1.h, p0.b
+; CHECK-NEXT:    punpkhi p0.h, p0.b
+; CHECK-NEXT:    punpklo p2.h, p1.b
+; CHECK-NEXT:    punpkhi p1.h, p1.b
+; CHECK-NEXT:    ld1sb { z0.s }, p2/z, [x0]
+; CHECK-NEXT:    punpklo p2.h, p0.b
+; CHECK-NEXT:    punpkhi p0.h, p0.b
+; CHECK-NEXT:    ld1sb { z1.s }, p1/z, [x0, #1, mul vl]
+; CHECK-NEXT:    ld1sb { z2.s }, p2/z, [x0, #2, mul vl]
+; CHECK-NEXT:    ld1sb { z3.s }, p0/z, [x0, #3, mul vl]
+; CHECK-NEXT:    ret
+  %load = call <vscale x 16 x i8> @llvm.masked.load.nxv16i8(<vscale x 16 x i8>* %a, i32 2, <vscale x 16 x i1> %mask, <vscale x 16 x i8> undef)
+  %ext = sext <vscale x 16 x i8> %load to <vscale x 16 x i32>
+  ret <vscale x 16 x i32> %ext
+}
+
 declare <vscale x 2 x i8> @llvm.masked.load.nxv2i8(<vscale x 2 x i8>*, i32, <vscale x 2 x i1>, <vscale x 2 x i8>)
 declare <vscale x 2 x i16> @llvm.masked.load.nxv2i16(<vscale x 2 x i16>*, i32, <vscale x 2 x i1>, <vscale x 2 x i16>)
 declare <vscale x 2 x i32> @llvm.masked.load.nxv2i32(<vscale x 2 x i32>*, i32, <vscale x 2 x i1>, <vscale x 2 x i32>)
 declare <vscale x 4 x i8> @llvm.masked.load.nxv4i8(<vscale x 4 x i8>*, i32, <vscale x 4 x i1>, <vscale x 4 x i8>)
 declare <vscale x 4 x i16> @llvm.masked.load.nxv4i16(<vscale x 4 x i16>*, i32, <vscale x 4 x i1>, <vscale x 4 x i16>)
 declare <vscale x 8 x i8> @llvm.masked.load.nxv8i8(<vscale x 8 x i8>*, i32, <vscale x 8 x i1>, <vscale x 8 x i8>)
+declare <vscale x 16 x i8> @llvm.masked.load.nxv16i8(<vscale x 16 x i8>*, i32, <vscale x 16 x i1>, <vscale x 16 x i8>)
Index: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
===================================================================
--- llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -10642,14 +10642,14 @@
          "Mixing fixed width and scalable vectors when enveloping a type");
   EVT LoVT, HiVT;
   if (VTNumElts.getKnownMinValue() > EnvNumElts.getKnownMinValue()) {
-    LoVT = EnvVT;
+    LoVT = EVT::getVectorVT(*getContext(), EltTp, EnvNumElts);
     HiVT = EVT::getVectorVT(*getContext(), EltTp, VTNumElts - EnvNumElts);
     *HiIsEmpty = false;
   } else {
     // Flag that hi type has zero storage size, but return split envelop type
     // (this would be easier if vector types with zero elements were allowed).
     LoVT = EVT::getVectorVT(*getContext(), EltTp, VTNumElts);
-    HiVT = EnvVT;
+    HiVT = EVT::getVectorVT(*getContext(), EltTp, EnvNumElts);
     *HiIsEmpty = true;
   }
   return std::make_pair(LoVT, HiVT);


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D111996.380392.patch
Type: text/x-patch
Size: 4929 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20211018/5578bfc5/attachment.bin>