codeql: detect wrong metrics groups

exactly finds #7408

Author: two-heart

contrib/codeql/nightly/WrongMetricsGroup.ql

@@ -0,0 +1,49 @@
+/**
+ * @name Wrong metrics group in tile
+ * @description Metrics accessed in a tile should belong to that tile
+ * @kind problem
+ * @problem.severity warning
+ * @precision medium
+ * @id asymmetric-research/metrics-wrong-group
+ */
+
+import cpp
+
+
+class Tile extends File {
+  Tile() { this.getBaseName().matches("%_tile.%") }
+
+  string getName() {
+    exists(GlobalVariable v | v.getType().getName() = "fd_topo_run_tile_t" |
+      v.getLocation().getFile() = this.getFile() and
+      exists(Field f | f.hasName("name") |
+        v.getInitializer()
+            .getExpr()
+            .(ClassAggregateLiteral)
+            .getAFieldExpr(f)
+            .(StringLiteral)
+            .getValue() = result
+      )
+    )
+  }
+
+  string metricsName() {
+    /* Account for renames in topology.c */
+    if this.getLocation().getFile().getRelativePath() = "src/discof/resolv/fd_resolv_tile.c"
+    then result = "resolf"
+    else
+      if this.getLocation().getFile().getRelativePath() = "src/discof/bank/fd_bank_tile.c"
+      then result = "bankf"
+      else result = this.getName()
+  }
+}
+
+from ArrayExpr arrayAccess, MacroAccess ma, Tile t, string metricsGroup
+where
+  arrayAccess.getArrayBase().toString() = "fd_metrics_tl" and
+  inmacroexpansion(arrayAccess.getArrayOffset(), ma) and
+  ma.getMacroName().matches("FD_METRICS_%") and
+  arrayAccess.getFile() = t.getLocation().getFile() and
+  metricsGroup = ma.getMacroName().splitAt("_", 3) and
+  metricsGroup.toLowerCase() != t.metricsName()
+select arrayAccess, "Metrics group " + metricsGroup + " unexpected for tile " + t.getName()