[PATCH] D55227: [DebugInfo] Don't drop dbg.value's of nullptr

[Vedant Kumar via Phabricator via llvm-commits]

vsk added inline comments.


================
Comment at: lib/CodeGen/SelectionDAG/InstrEmitter.cpp:739
+    } else if (isa<ConstantPointerNull>(V) &&
+               V->getType()->getPointerAddressSpace() == 0) {
+      // For now, assume null pointers are zero-valued
----------------
getValueImpl() emits a DAG.getConstant(0) regardless of which address space is used.


================
Comment at: lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp:5305
+    if (isa<ConstantInt>(V) || isa<ConstantFP>(V) || isa<UndefValue>(V) ||
+        isa<ConstantPointerNull>(V)) {
       SDV = DAG.getConstantDbgValue(Variable, Expression, V, dl, SDNodeOrder);
----------------
I'm curious what happens if V is-a Constant, but not one of these constants (e.g ConstantAggregate). It seems unlikely that V would always be in NodeMap in that case.


Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D55227/new/

https://reviews.llvm.org/D55227