[llvm] [SandboxVec][DAG] Build actual dependencies (PR #111094)

[Sriraman Tallam via llvm-commits]

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@@ -20,13 +26,35 @@ using namespace llvm;
 struct DependencyGraphTest : public testing::Test {
   LLVMContext C;
   std::unique_ptr<Module> M;
+  std::unique_ptr<AssumptionCache> AC;
+  std::unique_ptr<DominatorTree> DT;
+  std::unique_ptr<BasicAAResult> BAA;
+  std::unique_ptr<AAResults> AA;
 
   void parseIR(LLVMContext &C, const char *IR) {
     SMDiagnostic Err;
     M = parseAssemblyString(IR, Err, C);
     if (!M)
       Err.print("DependencyGraphTest", errs());
   }
+
+  AAResults &getAA(llvm::Function &LLVMF) {
+    TargetLibraryInfoImpl TLII;
+    TargetLibraryInfo TLI(TLII);
+    AA = std::make_unique<AAResults>(TLI);
+    AC = std::make_unique<AssumptionCache>(LLVMF);
+    DT = std::make_unique<DominatorTree>(LLVMF);
+    BAA = std::make_unique<BasicAAResult>(M->getDataLayout(), LLVMF, TLI, *AC,
+                                          DT.get());
+    AA->addAAResult(*BAA);
+    return *AA;
+  }
+  /// \Returns true if there is a dependency: SrcN->DstN.
+  bool dependency(sandboxir::DGNode *SrcN, sandboxir::DGNode *DstN) {
+    const auto &Preds = DstN->memPreds();
+    auto It = find(Preds, SrcN);
+    return It != Preds.end();
+  }
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tmsri wrote:

Why not add this as a member function to DGNode?

https://github.com/llvm/llvm-project/pull/111094