[MLIR] move loopUnrollJamBy*Factor to loop transforms utils

[bondhugula]

Summary

The declarations for these were already part of transforms utils, but
the definitions were left in affine transforms. Move definitions to loop
transforms utils.

Signed-off-by: Uday Bondhugula <[e-mail]>

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

LogicalResult LoopUnrollAndJam::runOnAffineForOp(AffineForOp forOp) {
   // Otherwise, unroll jam by the command-line factor if one was specified.
   if (clUnrollJamFactor.getNumOccurrences() > 0)
     return loopUnrollJamByFactor(forOp, clUnrollJamFactor);
 
   // Unroll and jam by four otherwise.
   return loopUnrollJamByFactor(forOp, kDefaultUnrollJamFactor);
 }
 
-LogicalResult mlir::loopUnrollJamUpToFactor(AffineForOp forOp,
-                                            uint64_t unrollJamFactor) {
-  Optional<uint64_t> mayBeConstantTripCount = getConstantTripCount(forOp);
-
-  if (mayBeConstantTripCount.hasValue() &&
-      mayBeConstantTripCount.getValue() < unrollJamFactor)
-    return loopUnrollJamByFactor(forOp, mayBeConstantTripCount.getValue());
-  return loopUnrollJamByFactor(forOp, unrollJamFactor);
-}
-
-/// Unrolls and jams this loop by the specified factor.
-LogicalResult mlir::loopUnrollJamByFactor(AffineForOp forOp,
-                                          uint64_t unrollJamFactor) {
-  // Gathers all maximal sub-blocks of operations that do not themselves
-  // include a for op (a operation could have a descendant for op though
-  // in its tree).  Ignore the block terminators.
-  struct JamBlockGatherer {
-    // Store iterators to the first and last op of each sub-block found.
-    std::vector<std::pair<Block::iterator, Block::iterator>> subBlocks;
-
-    // This is a linear time walk.
-    void walk(Operation *op) {
-      for (auto &region : op->getRegions())
-        for (auto &block : region)
-          walk(block);
-    }
-    void walk(Block &block) {
-      for (auto it = block.begin(), e = std::prev(block.end()); it != e;) {
-        auto subBlockStart = it;
-        while (it != e && !isa<AffineForOp>(&*it))
-          ++it;
-        if (it != subBlockStart)
-          subBlocks.push_back({subBlockStart, std::prev(it)});
-        // Process all for insts that appear next.
-        while (it != e && isa<AffineForOp>(&*it))
-          walk(&*it++);
-      }
-    }
-  };
-
-  assert(unrollJamFactor >= 1 && "unroll jam factor should be >= 1");
-
-  if (unrollJamFactor == 1)
-    return promoteIfSingleIteration(forOp);
-
-  if (forOp.getBody()->empty() ||
-      forOp.getBody()->begin() == std::prev(forOp.getBody()->end()))
-    return failure();
-
-  // Loops where both lower and upper bounds are multi-result maps won't be
-  // unrolled (since the trip can't be expressed as an affine function in
-  // general).
-  // TODO(mlir-team): this may not be common, but we could support the case
-  // where the lower bound is a multi-result map and the ub is a single result
-  // one.
-  if (forOp.getLowerBoundMap().getNumResults() != 1)
-    return failure();
-
-  Optional<uint64_t> mayBeConstantTripCount = getConstantTripCount(forOp);
-  // If the trip count is lower than the unroll jam factor, no unroll jam.
-  if (mayBeConstantTripCount.hasValue() &&
-      mayBeConstantTripCount.getValue() < unrollJamFactor)
-    return failure();
-
-  auto *forInst = forOp.getOperation();
-
-  // Gather all sub-blocks to jam upon the loop being unrolled.
-  JamBlockGatherer jbg;
-  jbg.walk(forInst);
-  auto &subBlocks = jbg.subBlocks;
-
-  // Generate the cleanup loop if trip count isn't a multiple of
-  // unrollJamFactor.
-  if (getLargestDivisorOfTripCount(forOp) % unrollJamFactor != 0) {
-    // Insert the cleanup loop right after 'forOp'.
-    OpBuilder builder(forInst->getBlock(), std::next(Block::iterator(forInst)));
-    auto cleanupAffineForOp = cast<AffineForOp>(builder.clone(*forInst));
-    // Adjust the lower bound of the cleanup loop; its upper bound is the same
-    // as the original loop's upper bound.
-    AffineMap cleanupMap;
-    SmallVector<Value, 4> cleanupOperands;
-    getCleanupLoopLowerBound(forOp, unrollJamFactor, &cleanupMap,
-                             &cleanupOperands, builder);
-    cleanupAffineForOp.setLowerBound(cleanupOperands, cleanupMap);
-
-    // Promote the cleanup loop if it has turned into a single iteration loop.
-    promoteIfSingleIteration(cleanupAffineForOp);
-
-    // Adjust the upper bound of the original loop - it will be the same as the
-    // cleanup loop's lower bound. Its lower bound remains unchanged.
-    forOp.setUpperBound(cleanupOperands, cleanupMap);
-  }
-
-  // Scale the step of loop being unroll-jammed by the unroll-jam factor.
-  int64_t step = forOp.getStep();
-  forOp.setStep(step * unrollJamFactor);
-
-  auto forOpIV = forOp.getInductionVar();
-  // Unroll and jam (appends unrollJamFactor - 1 additional copies).
-  for (unsigned i = unrollJamFactor - 1; i >= 1; --i) {
-    // Operand map persists across all sub-blocks.
-    BlockAndValueMapping operandMapping;
-    for (auto &subBlock : subBlocks) {
-      // Builder to insert unroll-jammed bodies. Insert right at the end of
-      // sub-block.
-      OpBuilder builder(subBlock.first->getBlock(), std::next(subBlock.second));
-
-      // If the induction variable is used, create a remapping to the value for
-      // this unrolled instance.
-      if (!forOpIV.use_empty()) {
-        // iv' = iv + i, i = 1 to unrollJamFactor-1.
-        auto d0 = builder.getAffineDimExpr(0);
-        auto bumpMap = AffineMap::get(1, 0, {d0 + i * step});
-        auto ivUnroll =
-            builder.create<AffineApplyOp>(forInst->getLoc(), bumpMap, forOpIV);
-        operandMapping.map(forOpIV, ivUnroll);
-      }
-      // Clone the sub-block being unroll-jammed.
-      for (auto it = subBlock.first; it != std::next(subBlock.second); ++it) {
-        builder.clone(*it, operandMapping);
-      }
-    }
-  }
-
-  // Promote the loop body up if this has turned into a single iteration loop.
-  promoteIfSingleIteration(forOp);
-  return success();
-}
-
 static PassRegistration<LoopUnrollAndJam> pass("affine-loop-unroll-jam",
                                                "Unroll and jam loops");

mlir/lib/Transforms/Utils/LoopUtils.cpp

for (unsigned i = 1; i < unrollFactor; i++) {
     }
   }
 
   // Promote the loop body up if this has turned into a single iteration loop.
   promoteIfSingleIteration(forOp);
   return success();
 }
 
+LogicalResult mlir::loopUnrollJamUpToFactor(AffineForOp forOp,
+                                            uint64_t unrollJamFactor) {
+  Optional<uint64_t> mayBeConstantTripCount = getConstantTripCount(forOp);
+
+  if (mayBeConstantTripCount.hasValue() &&
+      mayBeConstantTripCount.getValue() < unrollJamFactor)
+    return loopUnrollJamByFactor(forOp, mayBeConstantTripCount.getValue());
+  return loopUnrollJamByFactor(forOp, unrollJamFactor);
+}
+
+/// Unrolls and jams this loop by the specified factor.
+LogicalResult mlir::loopUnrollJamByFactor(AffineForOp forOp,
+                                          uint64_t unrollJamFactor) {
+  // Gathers all maximal sub-blocks of operations that do not themselves
+  // include a for op (a operation could have a descendant for op though
+  // in its tree).  Ignore the block terminators.
+  struct JamBlockGatherer {
+    // Store iterators to the first and last op of each sub-block found.
+    std::vector<std::pair<Block::iterator, Block::iterator>> subBlocks;
+
+    // This is a linear time walk.
+    void walk(Operation *op) {
+      for (auto &region : op->getRegions())
+        for (auto &block : region)
+          walk(block);
+    }
+    void walk(Block &block) {
+      for (auto it = block.begin(), e = std::prev(block.end()); it != e;) {
+        auto subBlockStart = it;
+        while (it != e && !isa<AffineForOp>(&*it))
+          ++it;
+        if (it != subBlockStart)
+          subBlocks.push_back({subBlockStart, std::prev(it)});
+        // Process all for insts that appear next.
+        while (it != e && isa<AffineForOp>(&*it))
+          walk(&*it++);
+      }
+    }
+  };
+
+  assert(unrollJamFactor >= 1 && "unroll jam factor should be >= 1");
+
+  if (unrollJamFactor == 1)
+    return promoteIfSingleIteration(forOp);
+
+  if (forOp.getBody()->empty() ||
+      forOp.getBody()->begin() == std::prev(forOp.getBody()->end()))
+    return failure();
+
+  // Loops where both lower and upper bounds are multi-result maps won't be
+  // unrolled (since the trip can't be expressed as an affine function in
+  // general).
+  // TODO(mlir-team): this may not be common, but we could support the case
+  // where the lower bound is a multi-result map and the ub is a single result
+  // one.
+  if (forOp.getLowerBoundMap().getNumResults() != 1)
+    return failure();
+
+  Optional<uint64_t> mayBeConstantTripCount = getConstantTripCount(forOp);
+  // If the trip count is lower than the unroll jam factor, no unroll jam.
+  if (mayBeConstantTripCount.hasValue() &&
+      mayBeConstantTripCount.getValue() < unrollJamFactor)
+    return failure();
+
+  auto *forInst = forOp.getOperation();
+
+  // Gather all sub-blocks to jam upon the loop being unrolled.
+  JamBlockGatherer jbg;
+  jbg.walk(forInst);
+  auto &subBlocks = jbg.subBlocks;
+
+  // Generate the cleanup loop if trip count isn't a multiple of
+  // unrollJamFactor.
+  if (getLargestDivisorOfTripCount(forOp) % unrollJamFactor != 0) {
+    // Insert the cleanup loop right after 'forOp'.
+    OpBuilder builder(forInst->getBlock(), std::next(Block::iterator(forInst)));
+    auto cleanupAffineForOp = cast<AffineForOp>(builder.clone(*forInst));
+    // Adjust the lower bound of the cleanup loop; its upper bound is the same
+    // as the original loop's upper bound.
+    AffineMap cleanupMap;
+    SmallVector<Value, 4> cleanupOperands;
+    getCleanupLoopLowerBound(forOp, unrollJamFactor, &cleanupMap,
+                             &cleanupOperands, builder);
+    cleanupAffineForOp.setLowerBound(cleanupOperands, cleanupMap);
+
+    // Promote the cleanup loop if it has turned into a single iteration loop.
+    promoteIfSingleIteration(cleanupAffineForOp);
+
+    // Adjust the upper bound of the original loop - it will be the same as the
+    // cleanup loop's lower bound. Its lower bound remains unchanged.
+    forOp.setUpperBound(cleanupOperands, cleanupMap);
+  }
+
+  // Scale the step of loop being unroll-jammed by the unroll-jam factor.
+  int64_t step = forOp.getStep();
+  forOp.setStep(step * unrollJamFactor);
+
+  auto forOpIV = forOp.getInductionVar();
+  // Unroll and jam (appends unrollJamFactor - 1 additional copies).
+  for (unsigned i = unrollJamFactor - 1; i >= 1; --i) {
+    // Operand map persists across all sub-blocks.
+    BlockAndValueMapping operandMapping;
+    for (auto &subBlock : subBlocks) {
+      // Builder to insert unroll-jammed bodies. Insert right at the end of
+      // sub-block.
+      OpBuilder builder(subBlock.first->getBlock(), std::next(subBlock.second));
+
+      // If the induction variable is used, create a remapping to the value for
+      // this unrolled instance.
+      if (!forOpIV.use_empty()) {
+        // iv' = iv + i, i = 1 to unrollJamFactor-1.
+        auto d0 = builder.getAffineDimExpr(0);
+        auto bumpMap = AffineMap::get(1, 0, {d0 + i * step});
+        auto ivUnroll =
+            builder.create<AffineApplyOp>(forInst->getLoc(), bumpMap, forOpIV);
+        operandMapping.map(forOpIV, ivUnroll);
+      }
+      // Clone the sub-block being unroll-jammed.
+      for (auto it = subBlock.first; it != std::next(subBlock.second); ++it) {
+        builder.clone(*it, operandMapping);
+      }
+    }
+  }
+
+  // Promote the loop body up if this has turned into a single iteration loop.
+  promoteIfSingleIteration(forOp);
+  return success();
+}
+
 /// Performs loop interchange on 'forOpA' and 'forOpB', where 'forOpB' is
 /// nested within 'forOpA' as the only non-terminator operation in its block.
 void mlir::interchangeLoops(AffineForOp forOpA, AffineForOp forOpB) {
   auto *forOpAInst = forOpA.getOperation();
 
   assert(&*forOpA.getBody()->begin() == forOpB.getOperation());
   auto &forOpABody = forOpA.getBody()->getOperations();
   auto &forOpBBody = forOpB.getBody()->getOperations();