[mlir][Affine] Use stable sorting to prevent non-determinism

[tpopp]

Pass container instead of begin/end to sort

mlir/lib/Dialect/Affine/Transforms/DecomposeAffineOps.cpp

void mlir::reorderOperandsByHoistability(RewriterBase &rewriter,
   SmallVector<int64_t> numInvariant = llvm::to_vector(
       llvm::map_range(op->getOpOperands(), [&](OpOperand &operand) {
         return numEnclosingInvariantLoops(operand);
       }));
 
   int64_t numOperands = op.getNumOperands();
   SmallVector<int64_t> operandPositions =
       llvm::to_vector(llvm::seq<int64_t>(0, numOperands));
-  std::sort(operandPositions.begin(), operandPositions.end(),
+  llvm::stable_sort(operandPositions.begin(), operandPositions.end(),
                     [&numInvariant](size_t i1, size_t i2) {
                       return numInvariant[i1] > numInvariant[i2];
                     });
 
   SmallVector<AffineExpr> replacements(numOperands);
   SmallVector<Value> operands(numOperands);
   for (int64_t i = 0; i < numOperands; ++i) {
     operands[i] = op.getOperand(operandPositions[i]);
     replacements[operandPositions[i]] = getAffineSymbolExpr(i, op.getContext());
   }
 
FailureOr<AffineApplyOp> mlir::decompose(RewriterBase &rewriter,
   // This however won't be able to split expression that cannot be reassociated
   // such as ones that involve divs and multiple symbols.
   auto getMaxSymbol = [&](AffineExpr e) -> int64_t {
     for (int64_t i = m.getNumSymbols(); i >= 0; --i)
       if (e.isFunctionOfSymbol(i))
         return i;
     return -1;
   };
-  std::sort(subExpressions.begin(), subExpressions.end(),
+  llvm::stable_sort(subExpressions.begin(), subExpressions.end(),
                     [&](AffineExpr e1, AffineExpr e2) {
                       return getMaxSymbol(e1) < getMaxSymbol(e2);
                     });
   LLVM_DEBUG(
       llvm::interleaveComma(subExpressions, DBGS() << "--sorted subexprs: ");
       llvm::dbgs() << "\n");
 
   // 4. Merge sorted subExpressions iteratively, thus achieving reassociation.
   auto s0 = getAffineSymbolExpr(0, ctx);
   auto s1 = getAffineSymbolExpr(1, ctx);
   AffineMap binMap = AffineMap::get(