llvm-project/llvm/lib/CodeGen/MachineStripDebug.cpp

112 lines
3.8 KiB
C++

//===- MachineStripDebug.cpp - Strip debug info ---------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file This removes debug info from everything. It can be used to ensure
/// tests can be debugified without affecting the output MIR.
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/Passes.h"
#include "llvm/IR/DebugInfo.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Transforms/Utils/Debugify.h"
#define DEBUG_TYPE "mir-strip-debug"
using namespace llvm;
namespace {
cl::opt<bool>
OnlyDebugifiedDefault("mir-strip-debugify-only",
cl::desc("Should mir-strip-debug only strip debug "
"info from debugified modules by default"),
cl::init(true));
struct StripDebugMachineModule : public ModulePass {
bool runOnModule(Module &M) override {
if (OnlyDebugified) {
NamedMDNode *DebugifyMD = M.getNamedMetadata("llvm.debugify");
if (!DebugifyMD) {
LLVM_DEBUG(dbgs() << "Not stripping debug info"
" (debugify metadata not found)?\n");
return false;
}
}
MachineModuleInfo &MMI =
getAnalysis<MachineModuleInfoWrapperPass>().getMMI();
bool Changed = false;
for (Function &F : M.functions()) {
MachineFunction *MaybeMF = MMI.getMachineFunction(F);
if (!MaybeMF)
continue;
MachineFunction &MF = *MaybeMF;
for (MachineBasicBlock &MBB : MF) {
for (MachineBasicBlock::iterator I = MBB.begin(), E = MBB.end();
I != E;) {
if (I->isDebugInstr()) {
// FIXME: We should remove all of them. However, AArch64 emits an
// invalid `DBG_VALUE $lr` with only one operand instead of
// the usual three and has a test that depends on it's
// preservation. Preserve it for now.
if (I->getNumOperands() > 1) {
LLVM_DEBUG(dbgs() << "Removing debug instruction " << *I);
I = MBB.erase(I);
Changed |= true;
continue;
}
}
if (I->getDebugLoc()) {
LLVM_DEBUG(dbgs() << "Removing location " << *I);
I->setDebugLoc(DebugLoc());
Changed |= true;
++I;
continue;
}
LLVM_DEBUG(dbgs() << "Keeping " << *I);
++I;
}
}
}
Changed |= stripDebugifyMetadata(M);
return Changed;
}
StripDebugMachineModule() : StripDebugMachineModule(OnlyDebugifiedDefault) {}
StripDebugMachineModule(bool OnlyDebugified)
: ModulePass(ID), OnlyDebugified(OnlyDebugified) {}
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<MachineModuleInfoWrapperPass>();
AU.addPreserved<MachineModuleInfoWrapperPass>();
AU.setPreservesCFG();
}
static char ID; // Pass identification.
protected:
bool OnlyDebugified;
};
char StripDebugMachineModule::ID = 0;
} // end anonymous namespace
INITIALIZE_PASS_BEGIN(StripDebugMachineModule, DEBUG_TYPE,
"Machine Strip Debug Module", false, false)
INITIALIZE_PASS_END(StripDebugMachineModule, DEBUG_TYPE,
"Machine Strip Debug Module", false, false)
ModulePass *llvm::createStripDebugMachineModulePass(bool OnlyDebugified) {
return new StripDebugMachineModule(OnlyDebugified);
}