Move the complex address expression out of DIVariable and into an extra

argument of the llvm.dbg.declare/llvm.dbg.value intrinsics.

Previously, DIVariable was a variable-length field that has an optional
reference to a Metadata array consisting of a variable number of
complex address expressions. In the case of OpPiece expressions this is
wasting a lot of storage in IR, because when an aggregate type is, e.g.,
SROA'd into all of its n individual members, the IR will contain n copies
of the DIVariable, all alike, only differing in the complex address
reference at the end.

By making the complex address into an extra argument of the
dbg.value/dbg.declare intrinsics, all of the pieces can reference the
same variable and the complex address expressions can be uniqued across
the CU, too.
Down the road, this will allow us to move other flags, such as
"indirection" out of the DIVariable, too.

The new intrinsics look like this:
declare void @llvm.dbg.declare(metadata %storage, metadata %var, metadata %expr)
declare void @llvm.dbg.value(metadata %storage, i64 %offset, metadata %var, metadata %expr)

This patch adds a new LLVM-local tag to DIExpressions, so we can detect
and pretty-print DIExpression metadata nodes.

What this patch doesn't do:

This patch does not touch the "Indirect" field in DIVariable; but moving
that into the expression would be a natural next step.

http://reviews.llvm.org/D4919
rdar://problem/17994491

Thanks to dblaikie and dexonsmith for reviewing this patch!

Note: I accidentally committed a bogus older version of this patch previously.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@218787 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Adrian Prantl
2014-10-01 18:55:02 +00:00
parent 0ad623bb0d
commit 02474a32eb
257 changed files with 1534 additions and 1377 deletions

View File

@ -993,15 +993,16 @@ void SelectionDAGBuilder::resolveDanglingDebugInfo(const Value *V,
DebugLoc dl = DDI.getdl();
unsigned DbgSDNodeOrder = DDI.getSDNodeOrder();
MDNode *Variable = DI->getVariable();
MDNode *Expr = DI->getExpression();
uint64_t Offset = DI->getOffset();
// A dbg.value for an alloca is always indirect.
bool IsIndirect = isa<AllocaInst>(V) || Offset != 0;
SDDbgValue *SDV;
if (Val.getNode()) {
if (!EmitFuncArgumentDbgValue(V, Variable, Offset, IsIndirect, Val)) {
SDV = DAG.getDbgValue(Variable, Val.getNode(),
Val.getResNo(), IsIndirect,
Offset, dl, DbgSDNodeOrder);
if (!EmitFuncArgumentDbgValue(V, Variable, Expr, Offset, IsIndirect,
Val)) {
SDV = DAG.getDbgValue(Variable, Expr, Val.getNode(), Val.getResNo(),
IsIndirect, Offset, dl, DbgSDNodeOrder);
DAG.AddDbgValue(SDV, Val.getNode(), false);
}
} else
@ -4603,10 +4604,11 @@ static unsigned getTruncatedArgReg(const SDValue &N) {
/// EmitFuncArgumentDbgValue - If the DbgValueInst is a dbg_value of a function
/// argument, create the corresponding DBG_VALUE machine instruction for it now.
/// At the end of instruction selection, they will be inserted to the entry BB.
bool
SelectionDAGBuilder::EmitFuncArgumentDbgValue(const Value *V, MDNode *Variable,
int64_t Offset, bool IsIndirect,
const SDValue &N) {
bool SelectionDAGBuilder::EmitFuncArgumentDbgValue(const Value *V,
MDNode *Variable,
MDNode *Expr, int64_t Offset,
bool IsIndirect,
const SDValue &N) {
const Argument *Arg = dyn_cast<Argument>(V);
if (!Arg)
return false;
@ -4658,14 +4660,16 @@ SelectionDAGBuilder::EmitFuncArgumentDbgValue(const Value *V, MDNode *Variable,
return false;
if (Op->isReg())
FuncInfo.ArgDbgValues.push_back(BuildMI(MF, getCurDebugLoc(),
TII->get(TargetOpcode::DBG_VALUE),
IsIndirect,
Op->getReg(), Offset, Variable));
FuncInfo.ArgDbgValues.push_back(
BuildMI(MF, getCurDebugLoc(), TII->get(TargetOpcode::DBG_VALUE),
IsIndirect, Op->getReg(), Offset, Variable, Expr));
else
FuncInfo.ArgDbgValues.push_back(
BuildMI(MF, getCurDebugLoc(), TII->get(TargetOpcode::DBG_VALUE))
.addOperand(*Op).addImm(Offset).addMetadata(Variable));
BuildMI(MF, getCurDebugLoc(), TII->get(TargetOpcode::DBG_VALUE))
.addOperand(*Op)
.addImm(Offset)
.addMetadata(Variable)
.addMetadata(Expr));
return true;
}
@ -4785,6 +4789,7 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
case Intrinsic::dbg_declare: {
const DbgDeclareInst &DI = cast<DbgDeclareInst>(I);
MDNode *Variable = DI.getVariable();
MDNode *Expression = DI.getExpression();
const Value *Address = DI.getAddress();
DIVariable DIVar(Variable);
assert((!DIVar || DIVar.isVariable()) &&
@ -4820,16 +4825,16 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
FrameIndexSDNode *FINode = dyn_cast<FrameIndexSDNode>(N.getNode());
if (FINode)
// Byval parameter. We have a frame index at this point.
SDV = DAG.getFrameIndexDbgValue(Variable, FINode->getIndex(),
0, dl, SDNodeOrder);
SDV = DAG.getFrameIndexDbgValue(
Variable, Expression, FINode->getIndex(), 0, dl, SDNodeOrder);
else {
// Address is an argument, so try to emit its dbg value using
// virtual register info from the FuncInfo.ValueMap.
EmitFuncArgumentDbgValue(Address, Variable, 0, false, N);
EmitFuncArgumentDbgValue(Address, Variable, Expression, 0, false, N);
return nullptr;
}
} else if (AI)
SDV = DAG.getDbgValue(Variable, N.getNode(), N.getResNo(),
SDV = DAG.getDbgValue(Variable, Expression, N.getNode(), N.getResNo(),
true, 0, dl, SDNodeOrder);
else {
// Can't do anything with other non-AI cases yet.
@ -4842,7 +4847,8 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
} else {
// If Address is an argument then try to emit its dbg value using
// virtual register info from the FuncInfo.ValueMap.
if (!EmitFuncArgumentDbgValue(Address, Variable, 0, false, N)) {
if (!EmitFuncArgumentDbgValue(Address, Variable, Expression, 0, false,
N)) {
// If variable is pinned by a alloca in dominating bb then
// use StaticAllocaMap.
if (const AllocaInst *AI = dyn_cast<AllocaInst>(Address)) {
@ -4850,7 +4856,7 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
DenseMap<const AllocaInst*, int>::iterator SI =
FuncInfo.StaticAllocaMap.find(AI);
if (SI != FuncInfo.StaticAllocaMap.end()) {
SDV = DAG.getFrameIndexDbgValue(Variable, SI->second,
SDV = DAG.getFrameIndexDbgValue(Variable, Expression, SI->second,
0, dl, SDNodeOrder);
DAG.AddDbgValue(SDV, nullptr, false);
return nullptr;
@ -4871,6 +4877,7 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
return nullptr;
MDNode *Variable = DI.getVariable();
MDNode *Expression = DI.getExpression();
uint64_t Offset = DI.getOffset();
const Value *V = DI.getValue();
if (!V)
@ -4878,7 +4885,8 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
SDDbgValue *SDV;
if (isa<ConstantInt>(V) || isa<ConstantFP>(V) || isa<UndefValue>(V)) {
SDV = DAG.getConstantDbgValue(Variable, V, Offset, dl, SDNodeOrder);
SDV = DAG.getConstantDbgValue(Variable, Expression, V, Offset, dl,
SDNodeOrder);
DAG.AddDbgValue(SDV, nullptr, false);
} else {
// Do not use getValue() in here; we don't want to generate code at
@ -4890,10 +4898,10 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
if (N.getNode()) {
// A dbg.value for an alloca is always indirect.
bool IsIndirect = isa<AllocaInst>(V) || Offset != 0;
if (!EmitFuncArgumentDbgValue(V, Variable, Offset, IsIndirect, N)) {
SDV = DAG.getDbgValue(Variable, N.getNode(),
N.getResNo(), IsIndirect,
Offset, dl, SDNodeOrder);
if (!EmitFuncArgumentDbgValue(V, Variable, Expression, Offset,
IsIndirect, N)) {
SDV = DAG.getDbgValue(Variable, Expression, N.getNode(), N.getResNo(),
IsIndirect, Offset, dl, SDNodeOrder);
DAG.AddDbgValue(SDV, N.getNode(), false);
}
} else if (!V->use_empty() ) {