[Hexagon] Ensure proper ordering of instructions in HVC::AlignVectors

The shuffle reduction creates a dependency chain. Make sure that the
inputs to the next instruction are placed ahead of the instruction itself.

diff --git a/llvm/lib/Target/Hexagon/HexagonVectorCombine.cpp b/llvm/lib/Target/Hexagon/HexagonVectorCombine.cpp
index 3d9a297..2629b54 100644 (file)
--- a/llvm/lib/Target/Hexagon/HexagonVectorCombine.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonVectorCombine.cpp
@@ -982,15 +982,27 @@ auto AlignVectors::realignLoadGroup(IRBuilderBase &Builder,
     Value *Accum = UndefValue::get(HVC.getByteTy(B.Seg.Size));
     Builder.SetInsertPoint(cast<Instruction>(B.Seg.Val));
 
+    // We're generating a reduction, where each instruction depends on
+    // the previous one, so we need to order them according to the position
+    // of their inputs in the code.
+    std::vector<ByteSpan::Block *> ABlocks;
     for (ByteSpan::Block &S : ASection) {
-      if (S.Seg.Val == nullptr)
-        continue;
+      if (S.Seg.Val != nullptr)
+        ABlocks.push_back(&S);
+    }
+    llvm::sort(ABlocks,
+               [&](const ByteSpan::Block *A, const ByteSpan::Block *B) {
+                 return isEarlier(cast<Instruction>(A->Seg.Val),
+                                  cast<Instruction>(B->Seg.Val));
+               });
+    for (ByteSpan::Block *S : ABlocks) {
       // The processing of the data loaded by the aligned loads
       // needs to be inserted after the data is available.
-      Instruction *SegI = cast<Instruction>(S.Seg.Val);
+      Instruction *SegI = cast<Instruction>(S->Seg.Val);
       Builder.SetInsertPoint(&*std::next(SegI->getIterator()));
-      Value *Pay = HVC.vbytes(Builder, getPayload(S.Seg.Val));
-      Accum = HVC.insertb(Builder, Accum, Pay, S.Seg.Start, S.Seg.Size, S.Pos);
+      Value *Pay = HVC.vbytes(Builder, getPayload(S->Seg.Val));
+      Accum =
+          HVC.insertb(Builder, Accum, Pay, S->Seg.Start, S->Seg.Size, S->Pos);
     }
     // Instead of casting everything to bytes for the vselect, cast to the
     // original value type. This will avoid complications with casting masks.

diff --git a/llvm/test/CodeGen/Hexagon/autohvx/vector-align-order.ll b/llvm/test/CodeGen/Hexagon/autohvx/vector-align-order.ll
new file mode 100644 (file)
index 0000000..f8bf0e9
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/autohvx/vector-align-order.ll
@@ -0,0 +1,65 @@
+; RUN: llc -march=hexagon < %s | FileCheck %s
+
+; Check that this doesn't crash.
+; CHECK: vmem
+
+target datalayout = "e-m:e-p:32:32:32-a:0-n16:32-i64:64:64-i32:32:32-i16:16:16-i1:8:8-f32:32:32-f64:64:64-v32:32:32-v64:64:64-v512:512:512-v1024:1024:1024-v2048:2048:2048"
+target triple = "hexagon"
+
+@g0 = external dllexport local_unnamed_addr global ptr, align 4
+@g1 = external dllexport local_unnamed_addr global ptr, align 4
+
+define dso_local fastcc void @f0(ptr %a0, i32 %a1) unnamed_addr #0 {
+b0:
+  %v0 = load ptr, ptr @g1, align 4
+  %v1 = tail call ptr %v0(i32 16, i32 %a1, i64 2400, i32 0, i32 32)
+  br i1 poison, label %b2, label %b1
+
+b1:                                               ; preds = %b0
+  %v2 = load <64 x i8>, ptr poison, align 64
+  %v3 = zext <64 x i8> %v2 to <64 x i32>
+  %v4 = load <128 x i8>, ptr poison, align 64
+  %v5 = zext <128 x i8> %v4 to <128 x i32>
+  %v6 = load <128 x i8>, ptr poison, align 64
+  %v7 = zext <128 x i8> %v6 to <128 x i32>
+  %v8 = getelementptr i8, ptr %a0, i32 576
+  %v9 = getelementptr i8, ptr %v8, i32 -64
+  %v10 = load <64 x i8>, ptr %v9, align 64
+  %v11 = sext <64 x i8> %v10 to <64 x i32>
+  %v12 = add nsw <64 x i32> %v11, <i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128>
+  %v13 = mul nuw nsw <64 x i32> %v12, %v3
+  %v14 = extractelement <64 x i32> %v13, i32 0
+  store i32 %v14, ptr %v1, align 8, !tbaa !0
+  %v15 = getelementptr i8, ptr %v8, i32 384
+  %v16 = load <128 x i8>, ptr %v15, align 64, !tbaa !3
+  %v17 = sext <128 x i8> %v16 to <128 x i32>
+  %v18 = add nsw <128 x i32> %v17, <i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128>
+  %v19 = mul nuw nsw <128 x i32> %v18, %v5
+  %v20 = getelementptr i8, ptr %v8, i32 256
+  %v21 = load <128 x i8>, ptr %v20, align 64, !tbaa !3
+  %v22 = sext <128 x i8> %v21 to <128 x i32>
+  %v23 = add nsw <128 x i32> %v22, <i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128, i32 128>
+  %v24 = mul nuw nsw <128 x i32> %v23, %v7
+  %v25 = add nsw <128 x i32> %v19, %v24
+  %v26 = extractelement <128 x i32> %v25, i32 0
+  %v27 = insertelement <64 x i32> <i32 poison, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0, i32 0>, i32 %v26, i64 0
+  %v28 = extractelement <64 x i32> %v27, i32 0
+  %v29 = getelementptr i8, ptr %v1, i32 4
+  store i32 %v28, ptr %v29, align 4
+  %v30 = load ptr, ptr @g0, align 4
+  %v31 = call i32 %v30(ptr nonnull @f1, ptr nonnull poison, i32 0)
+  unreachable
+
+b2:                                               ; preds = %b0
+  ret void
+}
+
+declare dso_local i32 @f1(i32, ptr, ptr) #0
+
+attributes #0 = { "target-features"="+hvxv68,+hvx-length128b,+hvx-qfloat,-hvx-ieee-fp" }
+
+!0 = !{!1, !1, i64 0}
+!1 = !{!"0x555e886c7bc0", !2, i64 0}
+!2 = !{!"tvm-tbaa"}
+!3 = !{!4, !4, i64 0}
+!4 = !{!"0x555e88cb2ce0", !2, i64 0}