[llvm] [SandboxVec][BottomUpVec] Implement InstrMaps (PR #122848)

[via llvm-commits]

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@@ -0,0 +1,77 @@
+//===- InstructionMaps.h ----------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_VECTORIZE_SANDBOXVEC_PASSES_INSTRUCTIONMAPS_H
+#define LLVM_TRANSFORMS_VECTORIZE_SANDBOXVEC_PASSES_INSTRUCTIONMAPS_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/SandboxIR/Value.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace llvm::sandboxir {
+
+/// Maps the original instructions to the vectorized instrs and the reverse.
+/// For now an original instr can only map to a single vector.
+class InstrMaps {
+  /// A map from the original values that got combined into vectors, to the
+  /// vector value(s).
+  DenseMap<Value *, Value *> OrigToVectorMap;
+  /// A map from the vector value to a map of the original value to its lane.
+  /// Please note that for constant vectors, there may multiple original values
+  /// with the same lane, as they may be coming from vectorizing different
+  /// original values.
+  DenseMap<Value *, DenseMap<Value *, unsigned>> VectorToOrigLaneMap;
+
+public:
+  /// \Returns all the vector value that we got from vectorizing \p Orig, or
+  /// nullptr if not found.
+  Value *getVectorForOrig(Value *Orig) const {
+    auto It = OrigToVectorMap.find(Orig);
+    return It != OrigToVectorMap.end() ? It->second : nullptr;
+  }
+  /// \Returns the lane of \p Orig before it got vectorized into \p Vec, or
+  /// nullopt if not found.
+  std::optional<int> getOrigLane(Value *Vec, Value *Orig) const {
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vporpo wrote:

I will change it to optional<unsigned>.

https://github.com/llvm/llvm-project/pull/122848