Preserve deleted function's local variables' debug info.

Radar 8122864.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107027 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Devang Patel 2010-06-28 18:25:03 +00:00
parent 3d895b974d
commit 4a1cad673c
3 changed files with 53 additions and 0 deletions

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@ -1386,6 +1386,7 @@ static bool isSubprogramContext(const MDNode *Context) {
/// If there are global variables in this scope then create and insert
/// DIEs for these variables.
DIE *DwarfDebug::updateSubprogramScopeDIE(const MDNode *SPNode) {
ProcessedSPNodes.insert(SPNode);
CompileUnit *SPCU = getCompileUnit(SPNode);
DIE *SPDie = SPCU->getDIE(SPNode);
assert(SPDie && "Unable to find subprogram DIE!");
@ -2005,6 +2006,40 @@ void DwarfDebug::beginModule(Module *M) {
///
void DwarfDebug::endModule() {
if (!FirstCU) return;
const Module *M = MMI->getModule();
if (NamedMDNode *AllSPs = M->getNamedMetadata("llvm.dbg.sp")) {
for (unsigned SI = 0, SE = AllSPs->getNumOperands(); SI != SE; ++SI) {
if (ProcessedSPNodes.count(AllSPs->getOperand(SI)) != 0) continue;
DISubprogram SP(AllSPs->getOperand(SI));
if (!SP.Verify()) continue;
// Collect info for variables that were optimized out.
StringRef FName = SP.getLinkageName();
if (FName.empty())
FName = SP.getName();
NamedMDNode *NMD =
M->getNamedMetadata(Twine("llvm.dbg.lv.", getRealLinkageName(FName)));
if (!NMD) continue;
unsigned E = NMD->getNumOperands();
if (!E) continue;
DbgScope *Scope = new DbgScope(NULL, DIDescriptor(SP), NULL);
for (unsigned I = 0; I != E; ++I) {
DIVariable DV(NMD->getOperand(I));
if (!DV.Verify()) continue;
Scope->addVariable(new DbgVariable(DV));
}
// Construct subprogram DIE and add variables DIEs.
constructSubprogramDIE(SP);
DIE *ScopeDIE = getCompileUnit(SP)->getDIE(SP);
const SmallVector<DbgVariable *, 8> &Variables = Scope->getVariables();
for (unsigned i = 0, N = Variables.size(); i < N; ++i) {
DIE *VariableDIE = constructVariableDIE(Variables[i], Scope);
if (VariableDIE)
ScopeDIE->addChild(VariableDIE);
}
}
}
// Attach DW_AT_inline attribute with inlined subprogram DIEs.
for (SmallPtrSet<DIE *, 4>::iterator AI = InlinedSubprogramDIEs.begin(),

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@ -219,6 +219,10 @@ class DwarfDebug {
DenseMap<const MDNode *, SmallVector<InlineInfoLabels, 4> > InlineInfo;
SmallVector<const MDNode *, 4> InlinedSPNodes;
// ProcessedSPNodes - This is a collection of subprogram MDNodes that
// are processed to create DIEs.
SmallPtrSet<const MDNode *, 16> ProcessedSPNodes;
/// LabelsBeforeInsn - Maps instruction with label emitted before
/// instruction.
DenseMap<const MachineInstr *, MCSymbol *> LabelsBeforeInsn;

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@ -0,0 +1,14 @@
// RUN: %llvmgcc -S -O2 -g %s -o - | llc -O2 -o %t.s
// RUN: grep DW_TAG_structure_type %t.s | count 2
// Radar 8122864
// Code is not generated for function foo, but preserve type information of
// local variable xyz.
static foo() {
struct X { int a; int b; } xyz;
}
int bar() {
foo();
return 1;
}