[PATCH] D24131: Add NewAddressDescription, which can describe any type of address.

[Vitaly Buka via llvm-commits]

vitalybuka requested changes to this revision.
This revision now requires changes to proceed.

================
Comment at: lib/asan/asan_debugging.cc:87
@@ +86,3 @@
+  if (name && name_size > 0) name[0] = 0;
+  switch (descr.kind) {
+    case kAddressKindWild:
----------------
filcab wrote:
> If we add the default case, we get a clang warning, though. I can add a check that we have one of those, before the switch, but it will end up ugly:
> 
> `CHECK(descr.kind == kAddressKindWild || descr.kind == kAddressKindShadow || ...);`
> Should we also fix places like PrintHeapChunkAccess in asan_descriptions.cc, which does the same thing (not have a default case)?
> 
We have another internal switch so assert(region_kind) just before return should cover both

================
Comment at: lib/asan/asan_debugging.cc:108
@@ +107,3 @@
+      region_kind = "heap";
+      if (name && name_size > 0) name[0] = 0;
+      region_address = descr.heap.chunk_access.chunk_begin;
----------------
name[0] = 0; is already done at entry

================
Comment at: lib/asan/asan_debugging.cc:115
@@ +114,3 @@
+      if (!descr.stack.frame_descr) {
+        if (name && name_size > 0) name[0] = 0;
+        // region_{address,size} are already 0
----------------
name[0] = 0; is already done at entry

================
Comment at: lib/asan/asan_descriptions.h:185
@@ +184,3 @@
+  // We should be able to do without this struct after we deprecate VS2013.
+  AddressKind kind;
+  union {
----------------
I see.
How about following?


```
struct AddressDescriptionData {
 AddressKind kind;
 union {
    ShadowAddressDescription shadow;
    HeapAddressDescription heap;
    StackAddressDescription stack;
    GlobalAddressDescription global;
    uptr addr;
  };
  // No methods.
}

class AddressDescription {
 private:
  AddressDescriptionData data;

 public:
  AddressDescription() {
    ...
  }
   uptr Address() const ;
   uptr Print() const ;
   const ShadowAddressDescription* AsShadowAddress() const { 
      return "kind is ShadowAddress" ? &shadow : nullptr;
   };
}


```


https://reviews.llvm.org/D24131