CodeGen: Assert that inlined-at locations agree

As a follow-up to r234021, assert that a debug info intrinsic variable's
`MDLocalVariable::getInlinedAt()` always matches the
`MDLocation::getInlinedAt()` of its `!dbg` attachment.

The goal here is to get rid of `MDLocalVariable::getInlinedAt()`
entirely (PR22778), but I'll let these assertions bake for a while
first.

If you have an out-of-tree backend that just broke, you're probably
attaching the wrong `DebugLoc` to a `DBG_VALUE` instruction.  The one
you want is the location that was attached to the corresponding
`@llvm.dbg.declare` or `@llvm.dbg.value` call that you started with.

llvm-svn: 234038

1 files changed, 4 insertions, 13 deletions

diff --git a/llvm/lib/CodeGen/LiveDebugVariables.cpp b/llvm/lib/CodeGen/LiveDebugVariables.cpp
index e3791be..69869fd 100644
--- a/llvm/lib/CodeGen/LiveDebugVariables.cpp
+++ b/llvm/lib/CodeGen/LiveDebugVariables.cpp
@@ -269,12 +269,6 @@ public:
   void emitDebugValues(VirtRegMap *VRM,
                        LiveIntervals &LIS, const TargetInstrInfo &TRI);
 
-  /// findDebugLoc - Return DebugLoc used for this DBG_VALUE instruction. A
-  /// variable may have more than one corresponding DBG_VALUE instructions.
-  /// Only first one needs DebugLoc to identify variable's lexical scope
-  /// in source file.
-  DebugLoc findDebugLoc();
-
   /// getDebugLoc - Return DebugLoc of this UserValue.
   DebugLoc getDebugLoc() { return dl;}
   void print(raw_ostream &, const TargetRegisterInfo *);
@@ -942,11 +936,6 @@ findInsertLocation(MachineBasicBlock *MBB, SlotIndex Idx,
                               std::next(MachineBasicBlock::iterator(MI));
 }
 
-DebugLoc UserValue::findDebugLoc() {
-  DebugLoc D = dl;
-  dl = DebugLoc();
-  return D;
-}
 void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx,
                                  unsigned LocNo,
                                  LiveIntervals &LIS,
@@ -955,11 +944,13 @@ void UserValue::insertDebugValue(MachineBasicBlock *MBB, SlotIndex Idx,
   MachineOperand &Loc = locations[LocNo];
   ++NumInsertedDebugValues;
 
+  assert(DIVariable(Variable)->isValidLocationForIntrinsic(getDebugLoc()) &&
+         "Expected inlined-at fields to agree");
   if (Loc.isReg())
-    BuildMI(*MBB, I, findDebugLoc(), TII.get(TargetOpcode::DBG_VALUE),
+    BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE),
             IsIndirect, Loc.getReg(), offset, Variable, Expression);
   else
-    BuildMI(*MBB, I, findDebugLoc(), TII.get(TargetOpcode::DBG_VALUE))
+    BuildMI(*MBB, I, getDebugLoc(), TII.get(TargetOpcode::DBG_VALUE))
         .addOperand(Loc)
         .addImm(offset)
         .addMetadata(Variable)