[PATCH] D128302: [AArch64][CostModel] Detects that ExtractElement at index is not free in AArch64 when result is used as integer.

[David Li via Phabricator via llvm-commits]

davidxl added inline comments.


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Comment at: llvm/include/llvm/Analysis/TargetTransformInfo.h:1155
 
   /// \return The expected cost of vector Insert and Extract.
   /// Use -1 to indicate that there is no information on the index value.
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Perhaps document this that this is used when the instruction is not available.


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Comment at: llvm/include/llvm/Analysis/TargetTransformInfo.h:1161
+  /// \return The expected cost of vector Insert and Extract.
+  /// Caller guarantees that 'I' is not nullptr.
+  ///
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Mention that this interface is used when I is available (and the interface implementation asserts it is not nullptr).


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Comment at: llvm/lib/Analysis/TargetTransformInfo.cpp:869
+  // callers, but never asserted upon.
+  assert((Opcode == Instruction::ExtractElement ||
+          Opcode == Instruction::InsertElement) &&
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probably submit this as a NFC patch seperately?


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Comment at: llvm/lib/Target/AArch64/AArch64TargetTransformInfo.h:176
 
+  using BaseT::getVectorInstrCost;
   InstructionCost getVectorInstrCost(unsigned Opcode, Type *Val,
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what is the purpose of the using statement here?


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  https://reviews.llvm.org/D128302/new/

https://reviews.llvm.org/D128302