[Mlir-commits] [mlir] [MLIR][Presburger] Implement computation of generating function for unimodular cones (PR #77235)

[Bharathi Ramana Joshi]

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@@ -63,3 +63,71 @@ MPInt mlir::presburger::detail::getIndex(ConeV cone) {
 
   return cone.determinant();
 }
+
+/// Compute the generating function for a unimodular cone.
+GeneratingFunction mlir::presburger::detail::unimodularConeGeneratingFunction(
+    ParamPoint vertex, int sign, ConeH cone) {
+  // `cone` is assumed to be unimodular.
+  assert(getIndex(getDual(cone)) == 1 && "input cone is not unimodular!");
+
+  unsigned numVar = cone.getNumVars();
+  unsigned numIneq = cone.getNumInequalities();
+
+  // Thus its ray matrix, U, is the inverse of the
+  // transpose of its inequality matrix, `cone`.
+  FracMatrix transp(numVar, numIneq);
+  for (unsigned i = 0; i < numVar; i++)
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iambrj wrote:

Use preincrements `++i` everywhere

https://github.com/llvm/llvm-project/pull/77235