[llvm] [DAG]SimplifyDemandedVectorElts-add ISD::AVGCEILS/AVGCEILU/AVGFLOORS/AVGFLOORU nodes (PR #86284)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-aarch64

Author: aniplcc (aniplcc)

<details>
<summary>Changes</summary>

Fixes #<!-- -->84768 

---
Full diff: https://github.com/llvm/llvm-project/pull/86284.diff


2 Files Affected:

- (modified) llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp (+4) 
- (modified) llvm/test/CodeGen/AArch64/hadd-combine.ll (+52) 


``````````diff
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
index da29b1d5b312f8..58d9394feb1237 100644
--- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp
@@ -3524,6 +3524,10 @@ bool TargetLowering::SimplifyDemandedVectorElts(
     }
     [[fallthrough]];
   }
+  case ISD::AVGCEILS:
+  case ISD::AVGCEILU:
+  case ISD::AVGFLOORS:
+  case ISD::AVGFLOORU:
   case ISD::OR:
   case ISD::XOR:
   case ISD::SUB:
diff --git a/llvm/test/CodeGen/AArch64/hadd-combine.ll b/llvm/test/CodeGen/AArch64/hadd-combine.ll
index e12502980790da..7c1c089839edc5 100644
--- a/llvm/test/CodeGen/AArch64/hadd-combine.ll
+++ b/llvm/test/CodeGen/AArch64/hadd-combine.ll
@@ -879,6 +879,58 @@ define <8 x i16> @uhadd_fixedwidth_v4i32(<8 x i16> %a0, <8 x i16> %a1)  {
   ret <8 x i16> %res
 }
 
+define <8 x i16> @shadd_demandedelts(<8 x i16> %a0, <8 x i16> %a1) {
+; CHECK-LABEL: shadd_demandedelts:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    shadd v0.8h, v0.8h, v1.8h
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    ret
+  %s0 = shufflevector <8 x i16> %a0, <8 x i16> undef, <8 x i32> zeroinitializer
+  %op = call <8 x i16> @llvm.aarch64.neon.shadd.v8i16(<8 x i16> %s0, <8 x i16> %a1)
+  %r0 = shufflevector <8 x i16> %op, <8 x i16> undef, <8 x i32> zeroinitializer
+  ret <8 x i16> %r0
+}
+
+define <8 x i16> @srhadd_demandedelts(<8 x i16> %a0, <8 x i16> %a1) {
+; CHECK-LABEL: srhadd_demandedelts:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    srhadd v0.8h, v0.8h, v1.8h
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    ret
+  %s0 = shufflevector <8 x i16> %a0, <8 x i16> undef, <8 x i32> zeroinitializer
+  %op = call <8 x i16> @llvm.aarch64.neon.srhadd.v8i16(<8 x i16> %s0, <8 x i16> %a1)
+  %r0 = shufflevector <8 x i16> %op, <8 x i16> undef, <8 x i32> zeroinitializer
+  ret <8 x i16> %r0
+}
+
+define <8 x i16> @uhadd_demandedelts(<8 x i16> %a0, <8 x i16> %a1) {
+; CHECK-LABEL: uhadd_demandedelts:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    uhadd v0.8h, v0.8h, v1.8h
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    ret
+  %s0 = shufflevector <8 x i16> %a0, <8 x i16> undef, <8 x i32> zeroinitializer
+  %op = call <8 x i16> @llvm.aarch64.neon.uhadd.v8i16(<8 x i16> %s0, <8 x i16> %a1)
+  %r0 = shufflevector <8 x i16> %op, <8 x i16> undef, <8 x i32> zeroinitializer
+  ret <8 x i16> %r0
+}
+
+define <8 x i16> @urhadd_demandedelts(<8 x i16> %a0, <8 x i16> %a1) {
+; CHECK-LABEL: urhadd_demandedelts:
+; CHECK:       // %bb.0:
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    urhadd v0.8h, v0.8h, v1.8h
+; CHECK-NEXT:    dup v0.8h, v0.h[0]
+; CHECK-NEXT:    ret
+  %s0 = shufflevector <8 x i16> %a0, <8 x i16> undef, <8 x i32> zeroinitializer
+  %op = call <8 x i16> @llvm.aarch64.neon.urhadd.v8i16(<8 x i16> %s0, <8 x i16> %a1)
+  %r0 = shufflevector <8 x i16> %op, <8 x i16> undef, <8 x i32> zeroinitializer
+  ret <8 x i16> %r0
+}
+
 declare <8 x i8> @llvm.aarch64.neon.shadd.v8i8(<8 x i8>, <8 x i8>)
 declare <4 x i16> @llvm.aarch64.neon.shadd.v4i16(<4 x i16>, <4 x i16>)
 declare <2 x i32> @llvm.aarch64.neon.shadd.v2i32(<2 x i32>, <2 x i32>)

``````````

</details>


https://github.com/llvm/llvm-project/pull/86284