Improve llvm.dbg.declare intrinsic by referring directly to the storage in its first argument, via function-local metadata (instead of via a bitcast).

This patch also cleans up code that expects there to be a bitcast in the first argument and testcases that call llvm.dbg.declare.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93504 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 29 deletions

diff --git a/lib/Analysis/DebugInfo.cpp b/lib/Analysis/DebugInfo.cpp
index 15ca1fae08..59ba807dd0 100644
--- a/lib/Analysis/DebugInfo.cpp
+++ b/lib/Analysis/DebugInfo.cpp
@@ -599,9 +599,7 @@ void DIVariable::dump() const {
 //===----------------------------------------------------------------------===//
 
 DIFactory::DIFactory(Module &m)
-  : M(m), VMContext(M.getContext()), DeclareFn(0) {
-  EmptyStructPtr = PointerType::getUnqual(StructType::get(VMContext));
-}
+  : M(m), VMContext(M.getContext()), DeclareFn(0) {}
 
 Constant *DIFactory::GetTagConstant(unsigned TAG) {
   assert((TAG & LLVMDebugVersionMask) == 0 &&
@@ -1034,26 +1032,22 @@ DILocation DIFactory::CreateLocation(unsigned LineNo, unsigned ColumnNo,
 /// InsertDeclare - Insert a new llvm.dbg.declare intrinsic call.
 Instruction *DIFactory::InsertDeclare(Value *Storage, DIVariable D,
                                       Instruction *InsertBefore) {
-  // Cast the storage to a {}* for the call to llvm.dbg.declare.
-  Storage = new BitCastInst(Storage, EmptyStructPtr, "", InsertBefore);
-
   if (!DeclareFn)
     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 
-  Value *Args[] = { Storage, D.getNode() };
+  Value *Elts[] = { Storage };
+  Value *Args[] = { MDNode::get(Storage->getContext(), Elts, 1), D.getNode() };
   return CallInst::Create(DeclareFn, Args, Args+2, "", InsertBefore);
 }
 
 /// InsertDeclare - Insert a new llvm.dbg.declare intrinsic call.
 Instruction *DIFactory::InsertDeclare(Value *Storage, DIVariable D,
                                       BasicBlock *InsertAtEnd) {
-  // Cast the storage to a {}* for the call to llvm.dbg.declare.
-  Storage = new BitCastInst(Storage, EmptyStructPtr, "", InsertAtEnd);
-
   if (!DeclareFn)
     DeclareFn = Intrinsic::getDeclaration(&M, Intrinsic::dbg_declare);
 
-  Value *Args[] = { Storage, D.getNode() };
+  Value *Elts[] = { Storage };
+  Value *Args[] = { MDNode::get(Storage->getContext(), Elts, 1), D.getNode() };
   return CallInst::Create(DeclareFn, Args, Args+2, "", InsertAtEnd);
 }
 
@@ -1258,25 +1252,24 @@ Value *llvm::findDbgGlobalDeclare(GlobalVariable *V) {
 
 /// Finds the llvm.dbg.declare intrinsic corresponding to this value if any.
 /// It looks through pointer casts too.
-const DbgDeclareInst *llvm::findDbgDeclare(const Value *V, bool stripCasts) {
-  if (stripCasts) {
-    V = V->stripPointerCasts();
-
-    // Look for the bitcast.
-    for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
-          I != E; ++I)
-      if (isa<BitCastInst>(I)) {
-        const DbgDeclareInst *DDI = findDbgDeclare(*I, false);
-        if (DDI) return DDI;
-      }
+const DbgDeclareInst *llvm::findDbgDeclare(const Value *V) {
+  V = V->stripPointerCasts();
+  
+  if (!isa<Instruction>(V) && !isa<Argument>(V))
     return 0;
-  }
-
-  // Find llvm.dbg.declare among uses of the instruction.
-  for (Value::use_const_iterator I = V->use_begin(), E =V->use_end();
-        I != E; ++I)
-    if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(I))
-      return DDI;
+    
+  const Function *F = NULL;
+  if (const Instruction *I = dyn_cast<Instruction>(V))
+    F = I->getParent()->getParent();
+  else if (const Argument *A = dyn_cast<Argument>(V))
+    F = A->getParent();
+  
+  for (Function::const_iterator FI = F->begin(), FE = F->end(); FI != FE; ++FI)
+    for (BasicBlock::const_iterator BI = (*FI).begin(), BE = (*FI).end();
+         BI != BE; ++BI)
+      if (const DbgDeclareInst *DDI = dyn_cast<DbgDeclareInst>(BI))
+        if (DDI->getAddress() == V)
+          return DDI;
 
   return 0;
 }