[clang-tools-extra] [MLIR][Presburger] Define matrix inverse for rational matrices (PR #67382)

[Arjun P via cfe-commits]

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@@ -102,7 +102,7 @@ inline bool operator>=(const Fraction &x, const Fraction &y) {
 inline Fraction reduce(const Fraction &f) {
   if (f == Fraction(0))
     return Fraction(0, 1);
-  MPInt g = gcd(f.num, f.den);
+  MPInt g = gcd(abs(f.num), abs(f.den));
   return Fraction(f.num / g, f.den / g);
 }
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Superty wrote:

If this is a bug fix please submit it as a separate patch along with a test case.

https://github.com/llvm/llvm-project/pull/67382