[llvm] [X86][CostModel] Free a clean narrow zext used as a GEP index (PR #216256)

[Simon Pilgrim via llvm-commits]

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@@ -51,12 +51,14 @@
 #include "X86TargetTransformInfo.h"
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
+#include "llvm/Analysis/ValueTracking.h"
 #include "llvm/CodeGen/Analysis.h"
 #include "llvm/CodeGen/BasicTTIImpl.h"
 #include "llvm/CodeGen/CostTable.h"
 #include "llvm/CodeGen/TargetLowering.h"
 #include "llvm/IR/InstIterator.h"
 #include "llvm/IR/IntrinsicInst.h"
+#include "llvm/Support/KnownBits.h"
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RKSimon wrote:

are these necessary? we already have KnownBits and computeKnownBits uses in this file and its likely a future iwyu pass will just remove them again.

https://github.com/llvm/llvm-project/pull/216256