From d4a19a396d06ba327838d7ebd936c9d4829bca78 Mon Sep 17 00:00:00 2001
From: "Duncan P. N. Exon Smith" <dexonsmith@apple.com>
Date: Tue, 21 Apr 2015 18:24:23 +0000
Subject: [PATCH] DebugInfo: Assert dbg.declare/value insts are valid

Remove early returns for when `getVariable()` is null, and just assert
that it never happens.  The Verifier already confirms that there's a
valid variable on these intrinsics, so we should assume the debug info
isn't broken.  I also updated a check for a `!dbg` attachment, which the
Verifier similarly guarantees.

llvm-svn: 235400
---
 llvm/lib/CodeGen/SelectionDAG/FastISel.cpp             | 4 ++--
 llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp | 5 +++--
 llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp  | 8 +++-----
 llvm/lib/Transforms/Utils/Local.cpp                    | 9 +++------
 4 files changed, 11 insertions(+), 15 deletions(-)

diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
index 5ffb826..dafbc63 100644
--- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -1088,8 +1088,8 @@ bool FastISel::selectIntrinsicCall(const IntrinsicInst *II) {
   }
   case Intrinsic::dbg_declare: {
     const DbgDeclareInst *DI = cast<DbgDeclareInst>(II);
-    DIVariable DIVar = DI->getVariable();
-    if (!DIVar || !FuncInfo.MF->getMMI().hasDebugInfo()) {
+    assert(DI->getVariable() && "Missing variable");
+    if (!FuncInfo.MF->getMMI().hasDebugInfo()) {
       DEBUG(dbgs() << "Dropping debug info for " << *DI << "\n");
       return true;
     }
diff --git a/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp b/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
index bb40326..b788232 100644
--- a/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp
@@ -202,8 +202,9 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf,
       // during the initial isel pass through the IR so that it is done
       // in a predictable order.
       if (const DbgDeclareInst *DI = dyn_cast<DbgDeclareInst>(I)) {
-        DIVariable DIVar = DI->getVariable();
-        if (MMI.hasDebugInfo() && DIVar && DI->getDebugLoc()) {
+        assert(DI->getVariable() && "Missing variable");
+        assert(DI->getDebugLoc() && "Missing location");
+        if (MMI.hasDebugInfo()) {
           // Don't handle byval struct arguments or VLAs, for example.
           // Non-byval arguments are handled here (they refer to the stack
           // temporary alloca at this point).
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index 32d2aae..49ea4b4 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -4650,8 +4650,8 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
     MDLocalVariable *Variable = DI.getVariable();
     MDExpression *Expression = DI.getExpression();
     const Value *Address = DI.getAddress();
-    DIVariable DIVar = Variable;
-    if (!Address || !DIVar) {
+    assert(Variable && "Missing variable");
+    if (!Address) {
       DEBUG(dbgs() << "Dropping debug info for " << DI << "\n");
       return nullptr;
     }
@@ -4728,9 +4728,7 @@ SelectionDAGBuilder::visitIntrinsicCall(const CallInst &I, unsigned Intrinsic) {
   }
   case Intrinsic::dbg_value: {
     const DbgValueInst &DI = cast<DbgValueInst>(I);
-    DIVariable DIVar = DI.getVariable();
-    if (!DIVar)
-      return nullptr;
+    assert(DI.getVariable() && "Missing variable");
 
     MDLocalVariable *Variable = DI.getVariable();
     MDExpression *Expression = DI.getExpression();
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 1c9760e..5672a36 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -1000,8 +1000,7 @@ bool llvm::ConvertDebugDeclareToDebugValue(DbgDeclareInst *DDI,
                                            StoreInst *SI, DIBuilder &Builder) {
   DIVariable DIVar = DDI->getVariable();
   DIExpression DIExpr = DDI->getExpression();
-  if (!DIVar)
-    return false;
+  assert(DIVar && "Missing variable");
 
   if (LdStHasDebugValue(DIVar, SI))
     return true;
@@ -1028,8 +1027,7 @@ bool llvm::ConvertDebugDeclareToDebugValue(DbgDeclareInst *DDI,
                                            LoadInst *LI, DIBuilder &Builder) {
   DIVariable DIVar = DDI->getVariable();
   DIExpression DIExpr = DDI->getExpression();
-  if (!DIVar)
-    return false;
+  assert(DIVar && "Missing variable");
 
   if (LdStHasDebugValue(DIVar, LI))
     return true;
@@ -1107,8 +1105,7 @@ bool llvm::replaceDbgDeclareForAlloca(AllocaInst *AI, Value *NewAllocaAddress,
   DebugLoc Loc = DDI->getDebugLoc();
   DIVariable DIVar = DDI->getVariable();
   DIExpression DIExpr = DDI->getExpression();
-  if (!DIVar)
-    return false;
+  assert(DIVar && "Missing variable");
 
   if (Deref) {
     // Create a copy of the original DIDescriptor for user variable, prepending
-- 
2.7.4