llvm/lib/Target/AMDGPU/AMDGPUFixFunctionBitcasts.cpp

   1 //===-- AMDGPUFixFunctionBitcasts.cpp - Fix function bitcasts -------------===//
   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 /// Promote indirect (bitcast) calls to direct calls when they are statically
  11 /// known to be direct. Required when InstCombine is not run (e.g. at OptNone)
  12 /// because AMDGPU does not support indirect calls.
  13 ///
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "AMDGPU.h"
  17 #include "llvm/IR/InstVisitor.h"
  18 #include "llvm/Pass.h"
  19 #include "llvm/Transforms/Utils/CallPromotionUtils.h"
  20
  21 using namespace llvm;
  22
  23 #define DEBUG_TYPE "amdgpu-fix-function-bitcasts"
  24
  25 namespace {
  26 class AMDGPUFixFunctionBitcasts final
  27     : public ModulePass,
  28       public InstVisitor<AMDGPUFixFunctionBitcasts> {
  29
  30   bool runOnModule(Module &M) override;
  31
  32   bool Modified;
  33
  34 public:
  35   void visitCallBase(CallBase &CB) {
  36     if (CB.getCalledFunction())
  37       return;
  38     auto *Callee =
  39         dyn_cast<Function>(CB.getCalledOperand()->stripPointerCasts());
  40     if (Callee && isLegalToPromote(CB, Callee)) {
  41       promoteCall(CB, Callee);
  42       Modified = true;
  43     }
  44   }
  45
  46   static char ID;
  47   AMDGPUFixFunctionBitcasts() : ModulePass(ID) {}
  48 };
  49 } // End anonymous namespace
  50
  51 char AMDGPUFixFunctionBitcasts::ID = 0;
  52 char &llvm::AMDGPUFixFunctionBitcastsID = AMDGPUFixFunctionBitcasts::ID;
  53 INITIALIZE_PASS(AMDGPUFixFunctionBitcasts, DEBUG_TYPE,
  54                 "Fix function bitcasts for AMDGPU", false, false)
  55
  56 ModulePass *llvm::createAMDGPUFixFunctionBitcastsPass() {
  57   return new AMDGPUFixFunctionBitcasts();
  58 }
  59
  60 bool AMDGPUFixFunctionBitcasts::runOnModule(Module &M) {
  61   Modified = false;
  62   visit(M);
  63   return Modified;
  64 }