[llvm] [AArch64] Ensure the type of LDNP/STNP is always v2i64 (PR #150378)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-aarch64

Author: David Green (davemgreen)

<details>
<summary>Changes</summary>

I think this is OK, that we always use v2i64 for the type of a LDNP/STNP nodes. Bitcasting the type should be fine for little endian. This helps with #<!-- -->150125.

---
Full diff: https://github.com/llvm/llvm-project/pull/150378.diff


2 Files Affected:

- (modified) llvm/lib/Target/AArch64/AArch64ISelLowering.cpp (+6-5) 
- (modified) llvm/lib/Target/AArch64/AArch64InstrInfo.td (+2-2) 


``````````diff
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index 02ee517a0a9b8..01b1ffaa5491f 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -6813,7 +6813,8 @@ SDValue AArch64TargetLowering::LowerSTORE(SDValue Op,
                       DAG.getConstant(EC.getKnownMinValue() / 2, Dl, MVT::i64));
       SDValue Result = DAG.getMemIntrinsicNode(
           AArch64ISD::STNP, Dl, DAG.getVTList(MVT::Other),
-          {StoreNode->getChain(), Lo, Hi, StoreNode->getBasePtr()},
+          {StoreNode->getChain(), DAG.getBitcast(MVT::v2i64, Lo),
+           DAG.getBitcast(MVT::v2i64, Hi), StoreNode->getBasePtr()},
           StoreNode->getMemoryVT(), StoreNode->getMemOperand());
       return Result;
     }
@@ -27907,16 +27908,16 @@ void AArch64TargetLowering::ReplaceNodeResults(
          MemVT.getScalarSizeInBits() == 32u ||
          MemVT.getScalarSizeInBits() == 64u)) {
 
+      EVT HalfVT = MemVT.getHalfNumVectorElementsVT(*DAG.getContext());
       SDValue Result = DAG.getMemIntrinsicNode(
           AArch64ISD::LDNP, SDLoc(N),
-          DAG.getVTList({MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
-                         MemVT.getHalfNumVectorElementsVT(*DAG.getContext()),
-                         MVT::Other}),
+          DAG.getVTList({MVT::v2i64, MVT::v2i64, MVT::Other}),
           {LoadNode->getChain(), LoadNode->getBasePtr()},
           LoadNode->getMemoryVT(), LoadNode->getMemOperand());
 
       SDValue Pair = DAG.getNode(ISD::CONCAT_VECTORS, SDLoc(N), MemVT,
-                                 Result.getValue(0), Result.getValue(1));
+                                 DAG.getBitcast(HalfVT, Result.getValue(0)),
+                                 DAG.getBitcast(HalfVT, Result.getValue(1)));
       Results.append({Pair, Result.getValue(2) /* Chain */});
       return;
     }
diff --git a/llvm/lib/Target/AArch64/AArch64InstrInfo.td b/llvm/lib/Target/AArch64/AArch64InstrInfo.td
index 9f8a2571b076e..3b5384e1e5cd6 100644
--- a/llvm/lib/Target/AArch64/AArch64InstrInfo.td
+++ b/llvm/lib/Target/AArch64/AArch64InstrInfo.td
@@ -518,10 +518,10 @@ def SDT_AArch64uaddlp : SDTypeProfile<1, 1, [SDTCisVec<0>, SDTCisVec<1>]>;
 
 def SDT_AArch64ldp : SDTypeProfile<2, 1, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 def SDT_AArch64ldiapp : SDTypeProfile<2, 1, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
-def SDT_AArch64ldnp : SDTypeProfile<2, 1, [SDTCisVT<0, v4i32>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
+def SDT_AArch64ldnp : SDTypeProfile<2, 1, [SDTCisVT<0, v2i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 def SDT_AArch64stp : SDTypeProfile<0, 3, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 def SDT_AArch64stilp : SDTypeProfile<0, 3, [SDTCisVT<0, i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
-def SDT_AArch64stnp : SDTypeProfile<0, 3, [SDTCisVT<0, v4i32>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
+def SDT_AArch64stnp : SDTypeProfile<0, 3, [SDTCisVT<0, v2i64>, SDTCisSameAs<0, 1>, SDTCisPtrTy<2>]>;
 
 // Generates the general dynamic sequences, i.e.
 //  adrp  x0, :tlsdesc:var

``````````

</details>


https://github.com/llvm/llvm-project/pull/150378