Merge pull request #11728 from github/rdmarsh2/parameterize-range-analysis

C++: Parameterize the semantic range analysis

Author: MathiasVP

cpp/ql/lib/experimental/semmle/code/cpp/semantic/analysis/FloatDelta.qll

@@ -0,0 +1,29 @@
+private import RangeAnalysisStage
+
+module FloatDelta implements DeltaSig {
+  class Delta = float;
+
+  bindingset[d]
+  bindingset[result]
+  float toFloat(Delta d) { result = d }
+
+  bindingset[d]
+  bindingset[result]
+  int toInt(Delta d) { result = d }
+
+  bindingset[n]
+  bindingset[result]
+  Delta fromInt(int n) { result = n }
+
+  bindingset[f]
+  Delta fromFloat(float f) {
+    result =
+      min(float diff, float res |
+        diff = (res - f) and res = f.ceil()
+        or
+        diff = (f - res) and res = f.floor()
+      |
+        res order by diff
+      )
+  }
+}