Fix PARI test fails for A077849 and improve IE for memory operations (#633)

Author: loader3229

src/eval/evaluator_inc.cpp

@@ -319,27 +319,35 @@ void IncrementalEvaluator::computeStatefulCells() {
   std::set<int64_t> write;
   stateful_cells.clear();
   for (const auto& op : simple_loop.body.ops) {
-    if (op.type == Operation::Type::CLR || op.type == Operation::Type::FIL ||
+    const auto target = op.target.value.asInt();
+    if (op.type == Operation::Type::CLR || op.type == Operation::Type::FIL || 
         op.type == Operation::Type::ROL || op.type == Operation::Type::ROR) {
-      // Set all cells affected by memory ops as stateful.
       auto bounds = ProgramUtil::getTargetMemoryRange(op);
       if (bounds.first == Number::INF || bounds.second == Number::INF) {
         continue;
       }
+      if (op.type == Operation::Type::FIL) {
+        read.insert(target);
+      }
       int64_t left = bounds.first.asInt();
       int64_t right = bounds.second.asInt();
       for (int64_t i = left; i < right; i++) {
-        read.insert(i);
-        write.insert(i);
-        stateful_cells.insert(i);
+        if (op.type == Operation::Type::ROL || op.type == Operation::Type::ROR) {
+          read.insert(i);
+        }
+        if (write.find(i) == write.end()) {
+          if (read.find(i) != read.end()) {
+            stateful_cells.insert(i);
+          }
+          write.insert(i);
+        }
       }
       continue;
     }
     const auto& meta = Operation::Metadata::get(op.type);
     if (meta.num_operands == 0) {
       continue;
     }
-    const auto target = op.target.value.asInt();
     if (target == simple_loop.counter) {
       continue;
     }
@@ -358,6 +366,11 @@ void IncrementalEvaluator::computeStatefulCells() {
       write.insert(target);
     }
   }
+  for (const auto& cell : read) {
+    if (write.find(cell) == write.end() && cell != simple_loop.counter) {
+      stateful_cells.insert(cell);
+    }
+  }
 }
 
 void IncrementalEvaluator::computeLoopCounterDependentCells() {

tests/formula/formula.txt

@@ -97,6 +97,7 @@ A054965: a(n) = logint(10^(n+1),3)
 A062815: a(n) = b(n+1), b(n) = n*n^n+b(n-1), b(0) = 0
 A060508: a(n) = logint(2^n,n)
 A060576: a(n) = n!=1
+A077849: a(n) = c(n+2), b(n) = 2*b(n-1)+b(n-2)+b(n-3)+d(n-1), b(3) = 8, b(2) = 3, b(1) = 1, b(0) = 0, c(n) = b(n-1), c(3) = 3, c(2) = 1, c(1) = 0, c(0) = 0, d(n) = d(n-1), d(3) = 1, d(2) = 1, d(1) = 1, d(0) = 1
 A078013: a(n) = -a(n-3)+a(n-1), a(4) = -1, a(3) = -1, a(2) = 0, a(1) = 0, a(0) = 1
 A080099: a(n) = bitand(-binomial(floor((sqrtint(8*n+1)+1)/2),2)+n,floor((sqrtint(8*n+1)+1)/2)-1)
 A092242: a(n) = 2*bitxor(3*n-3,1)+3

tests/formula/pari-function.txt

@@ -6,3 +6,4 @@ A000247: a(n) = 2^n-n-2
 A001286: a(n) = floor(((n-1)*n!)/2)
 A001715: (a(n) = truncate(b(n)/6)); (b(n) = if(n==0,1,n*b(n-1)))
 A006430: a(n) = truncate((floor(((-(1==n)+n)*(-(1==n)+n+1)*(-(1==n)+n+2)*(-(1==n)+n+3))/(-(1==n)+n+1))*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*((-(1==n)+n)*(23*n-23*(1==n)+963)+17544)+147952)+481675)-1052153)-7850914)-2900162)+60869272)+37067400)-179920800))/79833600)
+A077849: (a(n) = c(n+2)); (b(n) = if(n==3,8,if(n==2,3,if(n==1,1,if(n==0,0,2*b(n-1)+b(n-2)+b(n-3)+d(n-1)))))); (c(n) = if(n==3,3,if(n==2,1,if(n==1,0,if(n==0,0,b(n-1)))))); (d(n) = if(n==3,1,if(n==2,1,if(n==1,1,if(n==0,1,d(n-1))))))

tests/programs/oeis/077/A077849.asm

@@ -0,0 +1,14 @@
+; A077849: Expansion of (1-x)^(-1)/(1 - 2*x - x^2 - x^3).
+; 1,3,8,21,54,138,352,897,2285,5820,14823,37752,96148,244872,623645,1588311,4045140,10302237,26237926,66823230,170186624,433434405,1103878665,2811378360,7160069791,18235396608,46442241368,118279949136,301237536249,767197263003
+
+mov $4,1
+add $0,2
+lpb $0
+  sub $0,1
+  ror $1,3
+  add $1,$3
+  add $1,$2
+  add $1,$2
+  add $1,$4
+lpe
+mov $0,$2