[BOLT] Add function layout class

This patch adds a dedicated class to keep track of each function's
layout. It also lays the groundwork for splitting functions into
multiple fragments (as opposed to a strict hot/cold split).

Reviewed By: maksfb

Differential Revision: https://reviews.llvm.org/D129518

1 files changed, 19 insertions, 17 deletions

diff --git a/bolt/lib/Passes/ReorderAlgorithm.cpp b/bolt/lib/Passes/ReorderAlgorithm.cpp
index ba99622..0a69f71 100644
--- a/bolt/lib/Passes/ReorderAlgorithm.cpp
+++ b/bolt/lib/Passes/ReorderAlgorithm.cpp
@@ -136,10 +136,10 @@ void GreedyClusterAlgorithm::clusterBasicBlocks(const BinaryFunction &BF,
 
   // Initialize inter-cluster weights.
   if (ComputeEdges)
-    ClusterEdges.resize(BF.layout_size());
+    ClusterEdges.resize(BF.getLayout().block_size());
 
   // Initialize clusters and edge queue.
-  for (BinaryBasicBlock *BB : BF.layout()) {
+  for (BinaryBasicBlock *BB : BF.getLayout().blocks()) {
     // Create a cluster for this BB.
     uint32_t I = Clusters.size();
     Clusters.emplace_back();
@@ -169,7 +169,7 @@ void GreedyClusterAlgorithm::clusterBasicBlocks(const BinaryFunction &BF,
     LLVM_DEBUG(dbgs() << "Popped edge "; E.print(dbgs()); dbgs() << "\n");
 
     // Case 1: BBSrc and BBDst are the same. Ignore this edge
-    if (SrcBB == DstBB || DstBB == *BF.layout_begin()) {
+    if (SrcBB == DstBB || DstBB == *BF.getLayout().block_begin()) {
       LLVM_DEBUG(dbgs() << "\tIgnored (same src, dst)\n");
       continue;
     }
@@ -276,7 +276,8 @@ int64_t MinBranchGreedyClusterAlgorithm::calculateWeight(
            "overflow detected");
     // Ignore edges with same source and destination, edges that target the
     // entry block as well as the edge E itself.
-    if (SuccBB != SrcBB && SuccBB != *BF.layout_begin() && SuccBB != DstBB)
+    if (SuccBB != SrcBB && SuccBB != *BF.getLayout().block_begin() &&
+        SuccBB != DstBB)
       W -= (int64_t)BI->Count;
     ++BI;
   }
@@ -340,7 +341,7 @@ void MinBranchGreedyClusterAlgorithm::adjustQueue(std::vector<EdgeTy> &Queue,
 
     // Case 1: SrcBB and DstBB are the same or DstBB is the entry block. Ignore
     // this edge.
-    if (SrcBB == DstBB || DstBB == *BF.layout_begin()) {
+    if (SrcBB == DstBB || DstBB == *BF.getLayout().block_begin()) {
       LLVM_DEBUG(dbgs() << "\tAdjustment: Ignored edge "; E.print(dbgs());
                  dbgs() << " (same src, dst)\n");
       continue;
@@ -403,17 +404,17 @@ void TSPReorderAlgorithm::reorderBasicBlocks(const BinaryFunction &BF,
   std::vector<std::vector<uint64_t>> Weight;
   std::vector<BinaryBasicBlock *> IndexToBB;
 
-  const size_t N = BF.layout_size();
+  const size_t N = BF.getLayout().block_size();
   assert(N <= std::numeric_limits<uint64_t>::digits &&
          "cannot use TSP solution for sizes larger than bits in uint64_t");
 
   // Populating weight map and index map
-  for (BinaryBasicBlock *BB : BF.layout()) {
+  for (BinaryBasicBlock *BB : BF.getLayout().blocks()) {
     BB->setLayoutIndex(IndexToBB.size());
     IndexToBB.push_back(BB);
   }
   Weight.resize(N);
-  for (BinaryBasicBlock *BB : BF.layout()) {
+  for (BinaryBasicBlock *BB : BF.getLayout().blocks()) {
     auto BI = BB->branch_info_begin();
     Weight[BB->getLayoutIndex()].resize(N);
     for (BinaryBasicBlock *SuccBB : BB->successors()) {
@@ -495,14 +496,14 @@ void TSPReorderAlgorithm::reorderBasicBlocks(const BinaryFunction &BF,
 
   // Finalize layout with BBs that weren't assigned to the layout using the
   // input layout.
-  for (BinaryBasicBlock *BB : BF.layout())
+  for (BinaryBasicBlock *BB : BF.getLayout().blocks())
     if (Visited[BB->getLayoutIndex()] == false)
       Order.push_back(BB);
 }
 
 void OptimizeReorderAlgorithm::reorderBasicBlocks(
     const BinaryFunction &BF, BasicBlockOrder &Order) const {
-  if (BF.layout_empty())
+  if (BF.getLayout().block_empty())
     return;
 
   // Cluster basic blocks.
@@ -518,7 +519,7 @@ void OptimizeReorderAlgorithm::reorderBasicBlocks(
 
 void OptimizeBranchReorderAlgorithm::reorderBasicBlocks(
     const BinaryFunction &BF, BasicBlockOrder &Order) const {
-  if (BF.layout_empty())
+  if (BF.getLayout().block_empty())
     return;
 
   // Cluster basic blocks.
@@ -623,11 +624,12 @@ void OptimizeBranchReorderAlgorithm::reorderBasicBlocks(
 
 void OptimizeCacheReorderAlgorithm::reorderBasicBlocks(
     const BinaryFunction &BF, BasicBlockOrder &Order) const {
-  if (BF.layout_empty())
+  if (BF.getLayout().block_empty())
     return;
 
   const uint64_t ColdThreshold =
-      opts::ColdThreshold * (*BF.layout_begin())->getExecutionCount() / 1000;
+      opts::ColdThreshold *
+      (*BF.getLayout().block_begin())->getExecutionCount() / 1000;
 
   // Cluster basic blocks.
   CAlgo->clusterBasicBlocks(BF);
@@ -676,18 +678,18 @@ void OptimizeCacheReorderAlgorithm::reorderBasicBlocks(
 
 void ReverseReorderAlgorithm::reorderBasicBlocks(const BinaryFunction &BF,
                                                  BasicBlockOrder &Order) const {
-  if (BF.layout_empty())
+  if (BF.getLayout().block_empty())
     return;
 
-  BinaryBasicBlock *FirstBB = *BF.layout_begin();
+  BinaryBasicBlock *FirstBB = *BF.getLayout().block_begin();
   Order.push_back(FirstBB);
-  for (auto RLI = BF.layout_rbegin(); *RLI != FirstBB; ++RLI)
+  for (auto RLI = BF.getLayout().block_rbegin(); *RLI != FirstBB; ++RLI)
     Order.push_back(*RLI);
 }
 
 void RandomClusterReorderAlgorithm::reorderBasicBlocks(
     const BinaryFunction &BF, BasicBlockOrder &Order) const {
-  if (BF.layout_empty())
+  if (BF.getLayout().block_empty())
     return;
 
   // Cluster basic blocks.