[llvm-branch-commits] [llvm] [BOLT] Match blocks with pseudo probes (PR #99891)

[Davide Italiano via llvm-branch-commits]

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@@ -266,6 +313,65 @@ class StaleMatcher {
     }
     return BestBlock;
   }
+  // Uses pseudo probe information to attach the profile to the appropriate
+  // block.
+  const FlowBlock *matchWithPseudoProbes(
+      BlendedBlockHash BlendedHash,
+      const std::vector<yaml::bolt::PseudoProbeInfo> &PseudoProbes) const {
+    if (!YamlBFGUID)
+      return nullptr;
+
+    if (opts::Verbosity >= 3)
+      outs() << "BOLT-INFO: attempting to match block with pseudo probes\n";
+
+    // Searches for the pseudo probe attached to the matched function's block,
+    // ignoring pseudo probes attached to function calls and inlined functions'
+    // blocks.
+    std::vector<const yaml::bolt::PseudoProbeInfo *> BlockPseudoProbes;
+    for (const auto &PseudoProbe : PseudoProbes) {
+      // Ensures that pseudo probe information belongs to the appropriate
+      // function and not an inlined function.
+      if (PseudoProbe.GUID != YamlBFGUID)
+        continue;
+      // Skips pseudo probes attached to function calls.
+      if (PseudoProbe.Type != static_cast<uint8_t>(PseudoProbeType::Block))
+        continue;
+
+      BlockPseudoProbes.push_back(&PseudoProbe);
+    }
+    // Returns nullptr if there is not a 1:1 mapping of the yaml block pseudo
+    // probe and binary pseudo probe.
+    if (BlockPseudoProbes.size() == 0) {
+      if (opts::Verbosity >= 3)
+        errs() << "BOLT-WARNING: no pseudo probes in profile block\n";
+      return nullptr;
+    }
+    if (BlockPseudoProbes.size() > 1) {
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dcci wrote:

you can probably hoist the computation of size and compute it only once.

https://github.com/llvm/llvm-project/pull/99891