[llvm] [SandboxVec][Scheduler] Boilerplate and initial implementation. (PR #112449)

[Sriraman Tallam via llvm-commits]

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@@ -0,0 +1,161 @@
+//===- Scheduler.cpp ------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Transforms/Vectorize/SandboxVectorizer/Scheduler.h"
+
+namespace llvm::sandboxir {
+
+// TODO: Check if we can cache top/bottom to reduce compile-time.
+DGNode *SchedBundle::getTop() const {
+  DGNode *TopN = Nodes.front();
+  for (auto *N : drop_begin(Nodes)) {
+    if (N->getInstruction()->comesBefore(TopN->getInstruction()))
+      TopN = N;
+  }
+  return TopN;
+}
+
+DGNode *SchedBundle::getBot() const {
+  DGNode *BotN = Nodes.front();
+  for (auto *N : drop_begin(Nodes)) {
+    if (BotN->getInstruction()->comesBefore(N->getInstruction()))
+      BotN = N;
+  }
+  return BotN;
+}
+
+void SchedBundle::cluster(BasicBlock::iterator Where) {
+  for (auto *N : Nodes) {
+    auto *I = N->getInstruction();
+    if (I->getIterator() == Where)
+      ++Where; // Try to maintain bundle order.
+    I->moveBefore(*Where.getNodeParent(), Where);
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tmsri wrote:

Ignore this, I get why I am wrong.

https://github.com/llvm/llvm-project/pull/112449