bolt/lib/Passes/FixRISCVCallsPass.cpp

   1 //===- bolt/Passes/FixRISCVCallsPass.cpp ------------------------*- C++ -*-===//
   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 #include "bolt/Passes/FixRISCVCallsPass.h"
  10 #include "bolt/Core/ParallelUtilities.h"
  11
  12 #include <iterator>
  13
  14 using namespace llvm;
  15
  16 namespace llvm {
  17 namespace bolt {
  18
  19 void FixRISCVCallsPass::runOnFunction(BinaryFunction &BF) {
  20   auto &BC = BF.getBinaryContext();
  21   auto &MIB = BC.MIB;
  22   auto *Ctx = BC.Ctx.get();
  23
  24   for (auto &BB : BF) {
  25     for (auto II = BB.begin(); II != BB.end();) {
  26       if (MIB->isCall(*II) && !MIB->isIndirectCall(*II)) {
  27         auto *Target = MIB->getTargetSymbol(*II);
  28         assert(Target && "Cannot find call target");
  29
  30         MCInst OldCall = *II;
  31         auto L = BC.scopeLock();
  32
  33         if (MIB->isTailCall(*II))
  34           MIB->createTailCall(*II, Target, Ctx);
  35         else
  36           MIB->createCall(*II, Target, Ctx);
  37
  38         MIB->moveAnnotations(std::move(OldCall), *II);
  39         ++II;
  40         continue;
  41       }
  42
  43       auto NextII = std::next(II);
  44
  45       if (NextII == BB.end())
  46         break;
  47
  48       if (MIB->isRISCVCall(*II, *NextII)) {
  49         auto *Target = MIB->getTargetSymbol(*II);
  50         assert(Target && "Cannot find call target");
  51
  52         MCInst OldCall = *NextII;
  53         auto L = BC.scopeLock();
  54
  55         if (MIB->isTailCall(*NextII))
  56           MIB->createTailCall(*II, Target, Ctx);
  57         else
  58           MIB->createCall(*II, Target, Ctx);
  59
  60         MIB->moveAnnotations(std::move(OldCall), *II);
  61
  62         // The original offset was set on the jalr of the auipc+jalr pair. Since
  63         // the whole pair is replaced by a call, adjust the offset by -4 (the
  64         // size of a auipc).
  65         if (std::optional<uint32_t> Offset = MIB->getOffset(*II)) {
  66           assert(*Offset >= 4 && "Illegal jalr offset");
  67           MIB->setOffset(*II, *Offset - 4);
  68         }
  69
  70         II = BB.eraseInstruction(NextII);
  71         continue;
  72       }
  73
  74       ++II;
  75     }
  76   }
  77 }
  78
  79 Error FixRISCVCallsPass::runOnFunctions(BinaryContext &BC) {
  80   if (!BC.isRISCV() || !BC.HasRelocations)
  81     return Error::success();
  82
  83   ParallelUtilities::WorkFuncTy WorkFun = [&](BinaryFunction &BF) {
  84     runOnFunction(BF);
  85   };
  86
  87   ParallelUtilities::runOnEachFunction(
  88       BC, ParallelUtilities::SchedulingPolicy::SP_INST_LINEAR, WorkFun, nullptr,
  89       "FixRISCVCalls");
  90
  91   return Error::success();
  92 }
  93
  94 } // namespace bolt
  95 } // namespace llvm