[llvm] [AArch64] Optimize vector slide shuffles with zeros to use shift instructions (PR #185170)

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git-clang-format --diff origin/main HEAD --extensions cpp -- llvm/lib/Target/AArch64/AArch64ISelLowering.cpp --diff_from_common_commit
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``````````diff
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
index cf1a1a7ca..4a01cf867 100644
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -14587,7 +14587,6 @@ static bool isEXTMask(ArrayRef<int> M, EVT VT, bool &ReverseEXT,
   return true;
 }
 
-
 /// Flag slide shuffle patterns where one operand is zeros.
 /// Left slide: shufflevector %v, zeros, <1,2,3,...> -> ushr
 /// Right slide: shufflevector zeros, %v, <N-1,N,N+1,...> -> shl
@@ -14658,7 +14657,6 @@ static bool isSlideWithZerosMask(ArrayRef<int> M, EVT VT, SDValue V1,
   return false;
 }
 
-
 /// isZIP_v_undef_Mask - Special case of isZIPMask for canonical form of
 /// "vector_shuffle v, v", i.e., "vector_shuffle v, undef".
 /// Mask is e.g., <0, 0, 1, 1> instead of <0, 4, 1, 5>.

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https://github.com/llvm/llvm-project/pull/185170