forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			89 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			89 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C++
		
	
	
	
//===-- ResetMachineFunctionPass.cpp - Reset Machine Function ----*- C++ -*-==//
 | 
						|
//
 | 
						|
//                     The LLVM Compiler Infrastructure
 | 
						|
//
 | 
						|
// This file is distributed under the University of Illinois Open Source
 | 
						|
// License. See LICENSE.TXT for details.
 | 
						|
//
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
/// \file
 | 
						|
/// This file implements a pass that will conditionally reset a machine
 | 
						|
/// function as if it was just created. This is used to provide a fallback
 | 
						|
/// mechanism when GlobalISel fails, thus the condition for the reset to
 | 
						|
/// happen is that the MachineFunction has the FailedISel property.
 | 
						|
//===----------------------------------------------------------------------===//
 | 
						|
 | 
						|
#include "llvm/ADT/ScopeExit.h"
 | 
						|
#include "llvm/ADT/Statistic.h"
 | 
						|
#include "llvm/CodeGen/MachineFunction.h"
 | 
						|
#include "llvm/CodeGen/MachineFunctionPass.h"
 | 
						|
#include "llvm/CodeGen/MachineRegisterInfo.h"
 | 
						|
#include "llvm/CodeGen/StackProtector.h"
 | 
						|
#include "llvm/CodeGen/Passes.h"
 | 
						|
#include "llvm/IR/DiagnosticInfo.h"
 | 
						|
#include "llvm/Support/Debug.h"
 | 
						|
using namespace llvm;
 | 
						|
 | 
						|
#define DEBUG_TYPE "reset-machine-function"
 | 
						|
 | 
						|
STATISTIC(NumFunctionsReset, "Number of functions reset");
 | 
						|
 | 
						|
namespace {
 | 
						|
  class ResetMachineFunction : public MachineFunctionPass {
 | 
						|
    /// Tells whether or not this pass should emit a fallback
 | 
						|
    /// diagnostic when it resets a function.
 | 
						|
    bool EmitFallbackDiag;
 | 
						|
    /// Whether we should abort immediately instead of resetting the function.
 | 
						|
    bool AbortOnFailedISel;
 | 
						|
 | 
						|
  public:
 | 
						|
    static char ID; // Pass identification, replacement for typeid
 | 
						|
    ResetMachineFunction(bool EmitFallbackDiag = false,
 | 
						|
                         bool AbortOnFailedISel = false)
 | 
						|
        : MachineFunctionPass(ID), EmitFallbackDiag(EmitFallbackDiag),
 | 
						|
          AbortOnFailedISel(AbortOnFailedISel) {}
 | 
						|
 | 
						|
    StringRef getPassName() const override { return "ResetMachineFunction"; }
 | 
						|
 | 
						|
    void getAnalysisUsage(AnalysisUsage &AU) const override {
 | 
						|
      AU.addPreserved<StackProtector>();
 | 
						|
      MachineFunctionPass::getAnalysisUsage(AU);
 | 
						|
    }
 | 
						|
 | 
						|
    bool runOnMachineFunction(MachineFunction &MF) override {
 | 
						|
      // No matter what happened, whether we successfully selected the function
 | 
						|
      // or not, nothing is going to use the vreg types after us. Make sure they
 | 
						|
      // disappear.
 | 
						|
      auto ClearVRegTypesOnReturn =
 | 
						|
          make_scope_exit([&MF]() { MF.getRegInfo().clearVirtRegTypes(); });
 | 
						|
 | 
						|
      if (MF.getProperties().hasProperty(
 | 
						|
              MachineFunctionProperties::Property::FailedISel)) {
 | 
						|
        if (AbortOnFailedISel)
 | 
						|
          report_fatal_error("Instruction selection failed");
 | 
						|
        LLVM_DEBUG(dbgs() << "Resetting: " << MF.getName() << '\n');
 | 
						|
        ++NumFunctionsReset;
 | 
						|
        MF.reset();
 | 
						|
        if (EmitFallbackDiag) {
 | 
						|
          const Function &F = MF.getFunction();
 | 
						|
          DiagnosticInfoISelFallback DiagFallback(F);
 | 
						|
          F.getContext().diagnose(DiagFallback);
 | 
						|
        }
 | 
						|
        return true;
 | 
						|
      }
 | 
						|
      return false;
 | 
						|
    }
 | 
						|
 | 
						|
  };
 | 
						|
} // end anonymous namespace
 | 
						|
 | 
						|
char ResetMachineFunction::ID = 0;
 | 
						|
INITIALIZE_PASS(ResetMachineFunction, DEBUG_TYPE,
 | 
						|
                "Reset machine function if ISel failed", false, false)
 | 
						|
 | 
						|
MachineFunctionPass *
 | 
						|
llvm::createResetMachineFunctionPass(bool EmitFallbackDiag = false,
 | 
						|
                                     bool AbortOnFailedISel = false) {
 | 
						|
  return new ResetMachineFunction(EmitFallbackDiag, AbortOnFailedISel);
 | 
						|
}
 |