[llvm] [MemProf] Prune unneeded non-cold contexts (PR #124823)

[Teresa Johnson via llvm-commits]

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@@ -220,6 +221,48 @@ declare dso_local noalias noundef i8* @malloc(i64 noundef)
   EXPECT_EQ(Call4->getFnAttr("memprof").getValueAsString(), "notcold");
 }
 
+// TODO: Use this matcher in existing tests.
+// ExpectedVals should be a vector of expected MIBs and their allocation type
+// and stack id contents in order, of type:
+//  std::vector<std::pair<AllocationType, std::vector<unsigned>>>
+MATCHER_P(MemprofMetadataEquals, ExpectedVals, "Matching !memprof contents") {
+  auto PrintAndFail = [&]() {
+    std::string Buffer;
+    llvm::raw_string_ostream OS(Buffer);
+    OS << "Expected:\n";
+    for (auto &[ExpectedAllocType, ExpectedStackIds] : ExpectedVals) {
+      OS << "\t" << getAllocTypeAttributeString(ExpectedAllocType) << " { ";
+      for (auto Id : ExpectedStackIds)
+        OS << Id << " ";
+      OS << "}\n";
+    }
+    OS << "Got:\n";
+    arg->printTree(OS);
+    *result_listener << "!memprof metadata differs!\n" << Buffer;
+    return false;
+  };
+
+  if (ExpectedVals.size() != arg->getNumOperands())
+    return PrintAndFail();
+
+  for (size_t I = 0; I < ExpectedVals.size(); I++) {
+    const auto &[ExpectedAllocType, ExpectedStackIds] = ExpectedVals[I];
+    MDNode *MIB = dyn_cast<MDNode>(arg->getOperand(I));
+    if (getMIBAllocType(MIB) != ExpectedAllocType)
+      return PrintAndFail();
+    MDNode *StackMD = getMIBStackNode(MIB);
+    EXPECT_NE(StackMD, nullptr);
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teresajohnson wrote:

I had ASSERT_NE here first but I get a compiler error:

llvm/unittests/Analysis/MemoryProfileInfoTest.cpp:254:5: error: cannot initialize return object of type 'bool' with an rvalue of type 'void'
    ASSERT_NE(StackMD, nullptr);


https://github.com/llvm/llvm-project/pull/124823