Optimize ProbMask()

unitaryfund · Feb 23, 2023 · 388b29d · 388b29d
1 parent 2867733
commit 388b29d
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Showing 2 changed files with 4 additions and 3 deletions.
diff --git a/src/pinvoke_api.cpp b/src/pinvoke_api.cpp
@@ -2050,9 +2050,6 @@ MICROSOFT_QUANTUM_DECL double PermutationProb(
 
     try {
         QInterfacePtr simulator = simulators[sid];
-        if ((simulator->GetMaxQPower() - 1U) == mask) {
-            return (double)simulator->ProbAll(perm);
-        }
         return (double)simulator->ProbMask(mask, perm);
     } catch (...) {
         simulatorErrors[sid] = 1;

diff --git a/src/qinterface/qinterface.cpp b/src/qinterface/qinterface.cpp
@@ -270,6 +270,10 @@ real1_f QInterface::ProbReg(bitLenInt start, bitLenInt length, bitCapInt permuta
 /// Returns probability of permutation of the mask
 real1_f QInterface::ProbMask(bitCapInt mask, bitCapInt permutation)
 {
+    if ((maxQPower - 1U) == mask) {
+        return ProbAll(permutation);
+    }
+
     real1 prob = ZERO_R1;
     for (bitCapInt lcv = 0U; lcv < maxQPower; ++lcv) {
         if ((lcv & mask) == permutation) {