llvm/tools/llvm-reduce/deltas/ReduceAliases.cpp

   1 //===- ReduceAliases.cpp - Specialized Delta Pass -------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements a function which calls the Generic Delta pass in order
  10 // to reduce aliases in the provided Module.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "ReduceAliases.h"
  15 #include "Delta.h"
  16 #include "Utils.h"
  17 #include "llvm/IR/Constants.h"
  18 #include "llvm/IR/GlobalValue.h"
  19 #include "llvm/Transforms/Utils/ModuleUtils.h"
  20
  21 using namespace llvm;
  22
  23 /// Removes all aliases aren't inside any of the
  24 /// desired Chunks.
  25 static void extractAliasesFromModule(Oracle &O, ReducerWorkItem &Program) {
  26   for (auto &GA : make_early_inc_range(Program.getModule().aliases())) {
  27     if (!O.shouldKeep()) {
  28       GA.replaceAllUsesWith(GA.getAliasee());
  29       GA.eraseFromParent();
  30     }
  31   }
  32 }
  33
  34 static void extractIFuncsFromModule(Oracle &O, ReducerWorkItem &WorkItem) {
  35   Module &Mod = WorkItem.getModule();
  36
  37   std::vector<GlobalIFunc *> IFuncs;
  38   for (GlobalIFunc &GI : Mod.ifuncs()) {
  39     if (!O.shouldKeep())
  40       IFuncs.push_back(&GI);
  41   }
  42
  43   if (!IFuncs.empty())
  44     lowerGlobalIFuncUsersAsGlobalCtor(Mod, IFuncs);
  45 }
  46
  47 void llvm::reduceAliasesDeltaPass(TestRunner &Test) {
  48   runDeltaPass(Test, extractAliasesFromModule, "Reducing Aliases");
  49 }
  50
  51 void llvm::reduceIFuncsDeltaPass(TestRunner &Test) {
  52   runDeltaPass(Test, extractIFuncsFromModule, "Reducing Ifuncs");
  53 }