1 files changed, 104 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/Transforms/Utils/MatrixUtils.cpp b/contrib/llvm-project/llvm/lib/Transforms/Utils/MatrixUtils.cpp
new file mode 100644
index 000000000000..6a137630deeb
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/Transforms/Utils/MatrixUtils.cpp
@@ -0,0 +1,104 @@
+//===- MatrixUtils.cpp - Utilities to lower matrix intrinsics ---*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// Utilities for generating tiled loops for matrix operations.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Utils/MatrixUtils.h"
+#include "llvm/Analysis/DomTreeUpdater.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/IRBuilder.h"
+#include "llvm/IR/Type.h"
+
+using namespace llvm;
+
+BasicBlock *TileInfo::CreateLoop(BasicBlock *Preheader, BasicBlock *Exit,
+                                 Value *Bound, Value *Step, StringRef Name,
+                                 IRBuilderBase &B, DomTreeUpdater &DTU, Loop *L,
+                                 LoopInfo &LI) {
+  LLVMContext &Ctx = Preheader->getContext();
+  BasicBlock *Header = BasicBlock::Create(
+      Preheader->getContext(), Name + ".header", Preheader->getParent(), Exit);
+  BasicBlock *Body = BasicBlock::Create(Header->getContext(), Name + ".body",
+                                        Header->getParent(), Exit);
+  BasicBlock *Latch = BasicBlock::Create(Header->getContext(), Name + ".latch",
+                                         Header->getParent(), Exit);
+
+  Type *I32Ty = Type::getInt64Ty(Ctx);
+  BranchInst::Create(Body, Header);
+  BranchInst::Create(Latch, Body);
+  PHINode *IV =
+      PHINode::Create(I32Ty, 2, Name + ".iv", Header->getTerminator());
+  IV->addIncoming(ConstantInt::get(I32Ty, 0), Preheader);
+
+  B.SetInsertPoint(Latch);
+  Value *Inc = B.CreateAdd(IV, Step, Name + ".step");
+  Value *Cond = B.CreateICmpNE(Inc, Bound, Name + ".cond");
+  BranchInst::Create(Header, Exit, Cond, Latch);
+  IV->addIncoming(Inc, Latch);
+
+  BranchInst *PreheaderBr = cast<BranchInst>(Preheader->getTerminator());
+  BasicBlock *Tmp = PreheaderBr->getSuccessor(0);
+  PreheaderBr->setSuccessor(0, Header);
+  DTU.applyUpdatesPermissive({
+      {DominatorTree::Delete, Preheader, Tmp},
+      {DominatorTree::Insert, Header, Body},
+      {DominatorTree::Insert, Body, Latch},
+      {DominatorTree::Insert, Latch, Header},
+      {DominatorTree::Insert, Latch, Exit},
+      {DominatorTree::Insert, Preheader, Header},
+  });
+
+  L->addBasicBlockToLoop(Header, LI);
+  L->addBasicBlockToLoop(Body, LI);
+  L->addBasicBlockToLoop(Latch, LI);
+  return Body;
+}
+
+// Creates the following loop nest skeleton:
+//  for C = 0; C < NumColumns; C += TileSize
+//    for R = 0; R < NumRows; R += TileSize
+//      for K = 0; K < Inner ; K += TileSize
+BasicBlock *TileInfo::CreateTiledLoops(BasicBlock *Start, BasicBlock *End,
+                                       IRBuilderBase &B, DomTreeUpdater &DTU,
+                                       LoopInfo &LI) {
+  Loop *ColLoop = LI.AllocateLoop();
+  Loop *RowLoop = LI.AllocateLoop();
+  Loop *InnerLoop = LI.AllocateLoop();
+  RowLoop->addChildLoop(InnerLoop);
+  ColLoop->addChildLoop(RowLoop);
+  if (Loop *ParentL = LI.getLoopFor(Start))
+    ParentL->addChildLoop(ColLoop);
+  else
+    LI.addTopLevelLoop(ColLoop);
+
+  BasicBlock *ColBody =
+      CreateLoop(Start, End, B.getInt64(NumColumns), B.getInt64(TileSize),
+                 "cols", B, DTU, ColLoop, LI);
+  BasicBlock *ColLatch = ColBody->getSingleSuccessor();
+  BasicBlock *RowBody =
+      CreateLoop(ColBody, ColLatch, B.getInt64(NumRows), B.getInt64(TileSize),
+                 "rows", B, DTU, RowLoop, LI);
+  RowLoopLatch = RowBody->getSingleSuccessor();
+
+  BasicBlock *InnerBody =
+      CreateLoop(RowBody, RowLoopLatch, B.getInt64(NumInner),
+                 B.getInt64(TileSize), "inner", B, DTU, InnerLoop, LI);
+  InnerLoopLatch = InnerBody->getSingleSuccessor();
+  ColumnLoopHeader = ColBody->getSinglePredecessor();
+  RowLoopHeader = RowBody->getSinglePredecessor();
+  InnerLoopHeader = InnerBody->getSinglePredecessor();
+  CurrentRow = &*RowLoopHeader->begin();
+  CurrentCol = &*ColumnLoopHeader->begin();
+  CurrentK = &*InnerLoopHeader->begin();
+
+  return InnerBody;
+}