llvm/lib/Analysis/PtrUseVisitor.cpp

   1 //===- PtrUseVisitor.cpp - InstVisitors over a pointers uses --------------===//
   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 /// \file
  10 /// Implementation of the pointer use visitors.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/Analysis/PtrUseVisitor.h"
  15 #include "llvm/IR/Instruction.h"
  16 #include "llvm/IR/Instructions.h"
  17
  18 using namespace llvm;
  19
  20 void detail::PtrUseVisitorBase::enqueueUsers(Value &I) {
  21   for (Use &U : I.uses()) {
  22     if (VisitedUses.insert(&U).second) {
  23       UseToVisit NewU = {
  24         UseToVisit::UseAndIsOffsetKnownPair(&U, IsOffsetKnown),
  25         Offset
  26       };
  27       Worklist.push_back(std::move(NewU));
  28     }
  29   }
  30 }
  31
  32 bool detail::PtrUseVisitorBase::adjustOffsetForGEP(GetElementPtrInst &GEPI) {
  33   if (!IsOffsetKnown)
  34     return false;
  35
  36   APInt TmpOffset(DL.getIndexTypeSizeInBits(GEPI.getType()), 0);
  37   if (GEPI.accumulateConstantOffset(DL, TmpOffset)) {
  38     Offset += TmpOffset.sextOrTrunc(Offset.getBitWidth());
  39     return true;
  40   }
  41
  42   return false;
  43 }