[llvm] [GlobalISel] Cache split LLTs in IRTranslator (PR #195267)

[Alexis Engelke via llvm-commits]

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@@ -127,19 +138,29 @@ class IRTranslator : public MachineFunctionPass {
     }
 
     OffsetListT *insertOffsets(const Value &V) {
-      assert(!TypeToOffsets.contains(V.getType()) && "Type already exists");
-
       auto *OffsetList = new (OffsetAlloc.Allocate()) OffsetListT();
-      TypeToOffsets[V.getType()] = OffsetList;
-      return OffsetList;
+      auto [It, Inserted] = TypeToOffsets.insert({V.getType(), OffsetList});
+      if (!Inserted)
+        llvm_unreachable("Type already exists");
+      return It->second;
+    }
+
+    SplitTypeListT *insertSplitTys(const Value &V) {
+      auto *SplitTyList = new (SplitTyAlloc.Allocate()) SplitTypeListT();
+      auto [It, Inserted] = TypeToSplitTys.insert({V.getType(), SplitTyList});
+      if (!Inserted)
+        llvm_unreachable("Type already exists");
+      return It->second;
     }
     SpecificBumpPtrAllocator<VRegListT> VRegAlloc;
     SpecificBumpPtrAllocator<OffsetListT> OffsetAlloc;
+    SpecificBumpPtrAllocator<SplitTypeListT> SplitTyAlloc;
 
     // We store pointers to vectors here since references may be invalidated
     // while we hold them if we stored the vectors directly.
     DenseMap<const Value *, VRegListT*> ValToVRegs;
     DenseMap<const Type *, OffsetListT*> TypeToOffsets;
+    DenseMap<const Type *, SplitTypeListT *> TypeToSplitTys;
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aengelke wrote:

Couldn't we use a single hash map for offsets+split tys?

https://github.com/llvm/llvm-project/pull/195267