Update DebugInfo interface to use metadata, instead of special named llvm.dbg.... global variables, to encode debugging information in llvm IR. This is mostly a mechanical change that tests metadata support very well.

This change speeds up llvm-gcc by more then 6% at "-O0 -g" (measured by compiling InstructionCombining.cpp!)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@79977 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Devang Patel
2009-08-25 05:24:07 +00:00
parent 4bda11fbda
commit 2a610c7387
47 changed files with 966 additions and 1933 deletions

View File

@ -203,167 +203,56 @@ static bool StripSymbolNames(Module &M, bool PreserveDbgInfo) {
// llvm.dbg.region.end calls, and any globals they point to if now dead.
static bool StripDebugInfo(Module &M) {
SmallPtrSet<const GlobalValue*, 8> llvmUsedValues;
findUsedValues(M.getGlobalVariable("llvm.used"), llvmUsedValues);
findUsedValues(M.getGlobalVariable("llvm.compiler.used"), llvmUsedValues);
DebugInfoFinder DbgFinder;
DbgFinder.processModule(M);
// These anchors use LinkOnce linkage so that the optimizer does not
// remove them accidently. Set InternalLinkage for all these debug
// info anchors.
for (DebugInfoFinder::iterator I = DbgFinder.compile_unit_begin(),
E = DbgFinder.compile_unit_end(); I != E; ++I)
(*I)->setLinkage(GlobalValue::InternalLinkage);
for (DebugInfoFinder::iterator I = DbgFinder.global_variable_begin(),
E = DbgFinder.global_variable_end(); I != E; ++I)
(*I)->setLinkage(GlobalValue::InternalLinkage);
for (DebugInfoFinder::iterator I = DbgFinder.subprogram_begin(),
E = DbgFinder.subprogram_end(); I != E; ++I)
(*I)->setLinkage(GlobalValue::InternalLinkage);
// Delete all dbg variables.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
GlobalVariable *GV = dyn_cast<GlobalVariable>(I);
if (!GV) continue;
if (!GV->use_empty() && llvmUsedValues.count(I) == 0) {
if (GV->getName().startswith("llvm.dbg")) {
GV->replaceAllUsesWith(UndefValue::get(GV->getType()));
}
}
}
// Remove all of the calls to the debugger intrinsics, and remove them from
// the module.
Function *FuncStart = M.getFunction("llvm.dbg.func.start");
Function *StopPoint = M.getFunction("llvm.dbg.stoppoint");
Function *RegionStart = M.getFunction("llvm.dbg.region.start");
Function *RegionEnd = M.getFunction("llvm.dbg.region.end");
Function *Declare = M.getFunction("llvm.dbg.declare");
std::vector<Constant*> DeadConstants;
// Remove all of the calls to the debugger intrinsics, and remove them from
// the module.
if (FuncStart) {
while (!FuncStart->use_empty()) {
CallInst *CI = cast<CallInst>(FuncStart->use_back());
Value *Arg = CI->getOperand(1);
assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
CI->eraseFromParent();
if (Arg->use_empty())
if (Constant *C = dyn_cast<Constant>(Arg))
DeadConstants.push_back(C);
}
FuncStart->eraseFromParent();
}
if (StopPoint) {
while (!StopPoint->use_empty()) {
CallInst *CI = cast<CallInst>(StopPoint->use_back());
Value *Arg = CI->getOperand(3);
assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
CI->eraseFromParent();
if (Arg->use_empty())
if (Constant *C = dyn_cast<Constant>(Arg))
DeadConstants.push_back(C);
}
StopPoint->eraseFromParent();
}
if (RegionStart) {
while (!RegionStart->use_empty()) {
CallInst *CI = cast<CallInst>(RegionStart->use_back());
Value *Arg = CI->getOperand(1);
assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
CI->eraseFromParent();
if (Arg->use_empty())
if (Constant *C = dyn_cast<Constant>(Arg))
DeadConstants.push_back(C);
}
RegionStart->eraseFromParent();
}
if (RegionEnd) {
while (!RegionEnd->use_empty()) {
CallInst *CI = cast<CallInst>(RegionEnd->use_back());
Value *Arg = CI->getOperand(1);
assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
CI->eraseFromParent();
if (Arg->use_empty())
if (Constant *C = dyn_cast<Constant>(Arg))
DeadConstants.push_back(C);
}
RegionEnd->eraseFromParent();
}
if (Declare) {
while (!Declare->use_empty()) {
CallInst *CI = cast<CallInst>(Declare->use_back());
Value *Arg1 = CI->getOperand(1);
Value *Arg2 = CI->getOperand(2);
assert(CI->use_empty() && "llvm.dbg intrinsic should have void result");
CI->eraseFromParent();
if (Arg1->use_empty()) {
if (Constant *C = dyn_cast<Constant>(Arg1))
DeadConstants.push_back(C);
else
RecursivelyDeleteTriviallyDeadInstructions(Arg1);
}
if (Arg2->use_empty())
if (Constant *C = dyn_cast<Constant>(Arg2))
DeadConstants.push_back(C);
}
Declare->eraseFromParent();
}
// llvm.dbg.compile_units and llvm.dbg.subprograms are marked as linkonce
// but since we are removing all debug information, make them internal now.
// FIXME: Use private linkage maybe?
if (Constant *C = M.getNamedGlobal("llvm.dbg.compile_units"))
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
GV->setLinkage(GlobalValue::InternalLinkage);
NamedMDNode *NMD = M.getNamedMetadata("llvm.dbg.gv");
if (NMD)
NMD->eraseFromParent();
if (Constant *C = M.getNamedGlobal("llvm.dbg.subprograms"))
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
GV->setLinkage(GlobalValue::InternalLinkage);
if (Constant *C = M.getNamedGlobal("llvm.dbg.global_variables"))
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C))
GV->setLinkage(GlobalValue::InternalLinkage);
// Delete all dbg variables.
for (Module::global_iterator I = M.global_begin(), E = M.global_end();
I != E; ++I) {
GlobalVariable *GV = dyn_cast<GlobalVariable>(I);
if (!GV) continue;
if (GV->use_empty() && llvmUsedValues.count(I) == 0
&& (!GV->hasSection()
|| strcmp(GV->getSection().c_str(), "llvm.metadata") == 0))
DeadConstants.push_back(GV);
}
if (DeadConstants.empty())
return false;
// Delete any internal globals that were only used by the debugger intrinsics.
while (!DeadConstants.empty()) {
Constant *C = DeadConstants.back();
DeadConstants.pop_back();
if (GlobalVariable *GV = dyn_cast<GlobalVariable>(C)) {
if (GV->hasLocalLinkage())
RemoveDeadConstant(GV);
}
else
RemoveDeadConstant(C);
}
// Remove all llvm.dbg types.
TypeSymbolTable &ST = M.getTypeSymbolTable();
for (TypeSymbolTable::iterator TI = ST.begin(), TE = ST.end(); TI != TE; ) {
if (!strncmp(TI->first.c_str(), "llvm.dbg.", 9))
ST.remove(TI++);
else
++TI;
}
// Remove dead metadata.
M.getContext().RemoveDeadMetadata();
return true;
}