[Lldb-commits] [PATCH] D73860: [lldb/StringPrinter] Avoid reading garbage in uninitialized strings

[Shafik Yaghmour via Phabricator via lldb-commits]

shafik added inline comments.


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Comment at: lldb/packages/Python/lldbsuite/test/functionalities/data-formatter/data-formatter-stl/libcxx/string/main.cpp:23
+};
+static struct {
+  uint64_t cap = 5;
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This is much nicer then the previous raw arrays and self-documents with the fields, nice!


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Comment at: lldb/source/DataFormatters/StringPrinter.cpp:144
+    return retval;
+  if (!llvm::checkedAdd(reinterpret_cast<intptr_t>(buffer),
+                        static_cast<intptr_t>(utf8_encoded_len)))
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Wouldn't we want `checkedAddUnsigned`? This would also mean casting to `uintptr_t`.


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Comment at: lldb/source/DataFormatters/StringPrinter.cpp:474
       uint8_t *next_data = nullptr;
       auto printable = escaping_callback(data, data_end, next_data);
       auto printable_bytes = printable.GetBytes();
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Not your code but these `auto` seem unnecessary.  Especially `printable` is that just a `bool`?  Same comment in similar code above.


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Comment at: lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp:530
+
+    // When the small-string optimization takes place, the data must fit in the
+    // inline string buffer (23 bytes on x86_64/Darwin). If it doesn't, it's
----------------
So `short_mode` means SSO? 


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Comment at: lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp:555
+    size = size_vo->GetValueAsUnsigned(LLDB_INVALID_OFFSET);
+    const uint64_t cap = cap_vo->GetValueAsUnsigned(LLDB_INVALID_OFFSET);
+    if (size == LLDB_INVALID_OFFSET || cap == LLDB_INVALID_OFFSET || cap < size)
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What does `cap` represent? It is not obvious in this context.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D73860/new/

https://reviews.llvm.org/D73860