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

[Min-Yih Hsu via llvm-commits]

================
@@ -37,8 +37,16 @@ ResourcePressureView::ResourcePressureView(const llvm::MCSubtargetInfo &sti,
   }
 
   NumResourceUnits = R2VIndex;
-  ResourceUsage.resize(NumResourceUnits * (getSource().size() + 1));
-  std::fill(ResourceUsage.begin(), ResourceUsage.end(), 0.0);
+  ResourceUsage.resize(getSource().size());
+
+  ResourceReleaseAtCycles InitValue{0, 0};
+  auto Generator = [&InitValue]() {
+    auto Old = InitValue;
----------------
mshockwave wrote:

please spell out the type

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