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.

llvm-svn: 93504

include/llvm/Analysis/DebugInfo.h

@@ -491,7 +491,6 @@ namespace llvm {
     Module &M;
     LLVMContext& VMContext;
 
-    const Type *EmptyStructPtr; // "{}*".
     Function *DeclareFn;     // llvm.dbg.declare
     Function *ValueFn;       // llvm.dbg.value
 
@@ -659,7 +658,7 @@ namespace llvm {
 
   /// Finds the dbg.declare intrinsic corresponding to this value if any.
   /// It looks through pointer casts too.
-  const DbgDeclareInst *findDbgDeclare(const Value *V, bool stripCasts = true);
+  const DbgDeclareInst *findDbgDeclare(const Value *V);
 
   /// Find the debug info descriptor corresponding to this global variable.
   Value *findDbgGlobalDeclare(GlobalVariable *V);

include/llvm/IntrinsicInst.h

@@ -25,6 +25,7 @@
 #define LLVM_INTRINSICINST_H
 
 #include "llvm/Constants.h"
+#include "llvm/Metadata.h"
 #include "llvm/Function.h"
 #include "llvm/Instructions.h"
 #include "llvm/Intrinsics.h"
@@ -82,7 +83,12 @@ namespace llvm {
   ///
   class DbgDeclareInst : public DbgInfoIntrinsic {
   public:
-    Value *getAddress()  const { return getOperand(1); }
+    Value *getAddress() const {
+      if (MDNode* MD = dyn_cast<MDNode>(getOperand(1)))
+      	return MD->getOperand(0);
+      else
+      	return NULL;
+    }
     MDNode *getVariable() const { return cast<MDNode>(getOperand(2)); }
 
     // Methods for support type inquiry through isa, cast, and dyn_cast:

include/llvm/Intrinsics.td

@@ -283,7 +283,7 @@ let Properties = [IntrNoMem] in {
 // places.
 let Properties = [IntrNoMem] in {
   def int_dbg_declare      : Intrinsic<[llvm_void_ty],
-                                       [llvm_descriptor_ty, llvm_metadata_ty]>;
+                                       [llvm_metadata_ty, llvm_metadata_ty]>;
   def int_dbg_value  	   : Intrinsic<[llvm_void_ty],
                                        [llvm_metadata_ty, llvm_i64_ty,
                                         llvm_metadata_ty]>;

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;
 }

lib/CodeGen/SelectionDAG/FastISel.cpp

@@ -332,8 +332,6 @@ bool FastISel::SelectCall(User *I) {
       return true;
 
     Value *Address = DI->getAddress();
-    if (BitCastInst *BCI = dyn_cast<BitCastInst>(Address))
-      Address = BCI->getOperand(0);
     AllocaInst *AI = dyn_cast<AllocaInst>(Address);
     // Don't handle byval struct arguments or VLAs, for example.
     if (!AI) break;

lib/VMCore/Verifier.cpp

@@ -1590,9 +1590,10 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
   default:
     break;
   case Intrinsic::dbg_declare:  // llvm.dbg.declare
-    if (Constant *C = dyn_cast<Constant>(CI.getOperand(1)))
-      Assert1(C && !isa<ConstantPointerNull>(C),
-              "invalid llvm.dbg.declare intrinsic call", &CI);
+    if (MDNode *MD = dyn_cast<MDNode>(CI.getOperand(1)))
+      if (Constant *C = dyn_cast<Constant>(MD->getOperand(0)))
+        Assert1(C && !isa<ConstantPointerNull>(C),
+                "invalid llvm.dbg.declare intrinsic call", &CI);
     break;
   case Intrinsic::memcpy:
   case Intrinsic::memmove:

test/Assembler/functionlocal-metadata.ll

@@ -5,23 +5,21 @@ entry:
   %0 = add i32 %a, 1                              ; <i32> [#uses=1]
   %two = add i32 %b, %0                           ; <i32> [#uses=0]
   %1 = alloca i32                                 ; <i32*> [#uses=1]
-  %three = bitcast i32* %1 to { }*                ; <{ }*> [#uses=6]
 
-  call void @llvm.dbg.declare({ }* %three, metadata !{i32* %1})
-; CHECK: metadata !{i32* %1}
-  call void @llvm.dbg.declare({ }* %three, metadata !{{ }* %three})
-  call void @llvm.dbg.declare({ }* %three, metadata !{i32 %0})
-  call void @llvm.dbg.declare({ }* %three, metadata !{{ }* %three, i32 %0})
-  call void @llvm.dbg.declare({ }* %three, metadata !{i32 %b, i32 %0})
-  call void @llvm.dbg.declare({ }* %three, metadata !{i32 %a, metadata !"foo"})
+  call void @llvm.dbg.declare(metadata !{i32* %1}, metadata !{i32* %1})
+; CHECK: metadata !{i32* %1}, metadata !{i32* %1}
+  call void @llvm.dbg.declare(metadata !{i32 %two}, metadata !{i32 %0})
+  call void @llvm.dbg.declare(metadata !{i32 %0}, metadata !{i32* %1, i32 %0})
+  call void @llvm.dbg.declare(metadata !{i32* %1}, metadata !{i32 %b, i32 %0})
+  call void @llvm.dbg.declare(metadata !{i32 %a}, metadata !{i32 %a, metadata !"foo"})
 ; CHECK: metadata !{i32 %a, metadata !"foo"}
-  call void @llvm.dbg.declare({ }* %three, metadata !{metadata !0, i32 %two})
+  call void @llvm.dbg.declare(metadata !{i32 %b}, metadata !{metadata !0, i32 %two})
 
   call void @llvm.dbg.value(metadata !{ i32 %a }, i64 0, metadata !1)
   call void @llvm.dbg.value(metadata !{ i32 %0 }, i64 25, metadata !0)
   call void @llvm.dbg.value(metadata !{ i32* %1 }, i64 16, metadata !"foo")
 ; CHECK: call void @llvm.dbg.value(metadata !{i32* %1}, i64 16, metadata !"foo")
-  call void @llvm.dbg.value(metadata !{ { }* %three }, i64 12, metadata !"bar")
+  call void @llvm.dbg.value(metadata !"foo", i64 12, metadata !"bar")
 
   ret void, !foo !0, !bar !1
 ; CHECK: ret void, !foo !0, !bar !1
@@ -30,7 +28,7 @@ entry:
 !0 = metadata !{i32 662302, i32 26, metadata !1, null}
 !1 = metadata !{i32 4, metadata !"foo"}
 
-declare void @llvm.dbg.declare({ }*, metadata) nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 declare void @llvm.dbg.value(metadata, i64, metadata) nounwind readnone
 
 !foo = !{ !0 }

test/DebugInfo/2009-10-16-Scope.ll

@@ -9,8 +9,7 @@ entry:
   br label %do.body, !dbg !0
 
 do.body:                                          ; preds = %entry
-  %0 = bitcast i32* %count_ to { }*               ; <{ }*> [#uses=1]
-  call void @llvm.dbg.declare({ }* %0, metadata !4)
+  call void @llvm.dbg.declare(metadata !{i32* %count_}, metadata !4)
   %conv = ptrtoint i32* %count_ to i32, !dbg !0   ; <i32> [#uses=1]
   %call = call i32 @foo(i32 %conv) ssp, !dbg !0   ; <i32> [#uses=0]
   br label %do.end, !dbg !0
@@ -19,7 +18,7 @@ do.end:                                           ; preds = %do.body
   ret void, !dbg !7
 }
 
-declare void @llvm.dbg.declare({ }*, metadata) nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 
 declare i32 @foo(i32) ssp
 

test/DebugInfo/printdbginfo2.ll

@@ -19,11 +19,11 @@ entry:
   call void @llvm.dbg.stoppoint(i32 6, i32 3, metadata !1)
   call void @llvm.dbg.stoppoint(i32 7, i32 3, metadata !1)
   %0 = bitcast %struct.foo* %b to { }*            ; <{ }*> [#uses=1]
-  call void @llvm.dbg.declare({ }* %0, metadata !4)
+  call void @llvm.dbg.declare(metadata !{%struct.foo* %b}, metadata !4)
 ; CHECK:; %0 is variable b of type foo declared at x.c:7
   call void @llvm.dbg.stoppoint(i32 8, i32 3, metadata !1)
   %1 = bitcast [4 x i32]* %a to { }*              ; <{ }*> [#uses=1]
-  call void @llvm.dbg.declare({ }* %1, metadata !8)
+  call void @llvm.dbg.declare(metadata !{[4 x i32]* %a}, metadata !8)
 ; CHECK:; %1 is variable a of type  declared at x.c:8
   call void @llvm.dbg.stoppoint(i32 9, i32 3, metadata !1)
   %tmp = getelementptr inbounds %struct.foo* %b, i32 0, i32 0 ; <i32*> [#uses=1]
@@ -46,7 +46,7 @@ declare void @llvm.dbg.func.start(metadata) nounwind readnone
 
 declare void @llvm.dbg.stoppoint(i32, i32, metadata) nounwind readnone
 
-declare void @llvm.dbg.declare({ }*, metadata) nounwind readnone
+declare void @llvm.dbg.declare(metadata, metadata) nounwind readnone
 
 declare void @llvm.dbg.region.end(metadata) nounwind readnone