[llvm] Adding Matching and Inference Functionality to Propeller-PR2 (PR #162963)

[Rahman Lavaee via llvm-commits]

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@@ -0,0 +1,123 @@
+//===- llvm/CodeGen/MachineBlockHashInfo.cpp---------------------*- 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Compute the hashes of basic blocks.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/MachineBlockHashInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/InitializePasses.h"
+#include "llvm/Target/TargetMachine.h"
+
+using namespace llvm;
+
+using OperandHashFuncTy =
+    function_ref<uint64_t(uint64_t &, const MachineOperand &)>;
+
+uint64_t hashBlock(const MachineBasicBlock &MBB,
+                   OperandHashFuncTy OperandHashFunc) {
+  uint64_t Hash = 0;
+  for (const MachineInstr &MI : MBB) {
+    if (MI.isMetaInstruction())
+      continue;
+    // Ignore terminator instruction
+    if (MI.isTerminator())
+      continue;
+    Hash = hashing::detail::hash_16_bytes(Hash, MI.getOpcode());
+    for (unsigned i = 0; i < MI.getNumOperands(); i++) {
+      Hash = OperandHashFunc(Hash, MI.getOperand(i));
+    }
+  }
+  return Hash;
+}
+
+/// Hashing a 64-bit integer to a 16-bit one.
+uint16_t hash_64_to_16(const uint64_t Hash) {
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rlavaee wrote:

Suggestion for a better name: `fold_hash_64_to_16`.

https://github.com/llvm/llvm-project/pull/162963