[llvm] [MCA] Optimize memory consumption in resource pressure view (NFC) (PR #124904)

[Min-Yih Hsu via llvm-commits]

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@@ -180,17 +212,24 @@ json::Value ResourcePressureView::toJSON() const {
   // non-zero values.
   ArrayRef<llvm::MCInst> Source = getSource();
   const unsigned Executions = LastInstructionIdx / Source.size() + 1;
-  for (const auto &R : enumerate(ResourceUsage)) {
-    const ReleaseAtCycles &RU = R.value();
-    if (RU.getNumerator() == 0)
-      continue;
-    unsigned InstructionIndex = R.index() / NumResourceUnits;
-    unsigned ResourceIndex = R.index() % NumResourceUnits;
-    double Usage = RU / Executions;
+
+  auto AddToJSON = [&ResourcePressureInfo, Executions](
+                       const ResourceReleaseAtCycles &RU, unsigned InstIndex) {
+    assert(RU.Cycles.getNumerator() != 0);
+    double Usage = RU.Cycles / Executions;
     ResourcePressureInfo.push_back(
-        json::Object({{"InstructionIndex", InstructionIndex},
-                      {"ResourceIndex", ResourceIndex},
+        json::Object({{"InstructionIndex", InstIndex},
+                      {"ResourceIndex", RU.ResourceIdx},
                       {"ResourceUsage", Usage}}));
+  };
+  for (const auto &R : enumerate(ResourceUsage)) {
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mshockwave wrote:

nit: We can use `const auto &[..., ...] : enumerate(ResourceUsage)` now.

https://github.com/llvm/llvm-project/pull/124904