[llvm] [PGO] Add ProfileInjector and ProfileVerifier passes (PR #147388)

[Snehasish Kumar via llvm-commits]

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@@ -0,0 +1,111 @@
+//===- ProfileVerify.cpp - Verify profile info for testing ----------------===//
+//
+// 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/Utils/ProfileVerify.h"
+#include "llvm/ADT/DynamicAPInt.h"
+#include "llvm/ADT/PostOrderIterator.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/IR/Analysis.h"
+#include "llvm/IR/Dominators.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/MDBuilder.h"
+#include "llvm/IR/ProfDataUtils.h"
+#include "llvm/Support/BranchProbability.h"
+
+using namespace llvm;
+namespace {
+class ProfileInjector {
+  Function &F;
+  FunctionAnalysisManager &FAM;
+
+public:
+  static bool supportsBranchWeights(const Instruction &I) {
+    return isa<BranchInst>(&I) ||
+
+           isa<SwitchInst>(&I) ||
+
+           isa<IndirectBrInst>(&I) || isa<SelectInst>(&I) ||
+           isa<CallBrInst>(&I);
+  }
+
+  ProfileInjector(Function &F, FunctionAnalysisManager &FAM) : F(F), FAM(FAM) {}
+  bool inject();
+};
+} // namespace
+
+bool ProfileInjector::inject() {
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snehasish wrote:

Discussed offline, summarizing here. I'd like the engineering decisions (e.g. what the interface looks like, where the code resides) to be made sooner rather than later so that other contributors interested in prototyping heuristics do not have to bother. This can proceed in a separate follow patch. 

https://github.com/llvm/llvm-project/pull/147388