[Lldb-commits] [lldb] 8d06ef5 - [LLDB] Check that RegisterInfo and ContextInfo are trivial

[David Spickett via lldb-commits]

Author: David Spickett
Date: 2022-10-24T10:16:29Z
New Revision: 8d06ef5658187bf6a3eda61a5ec3627c1ff33fb8

URL: https://github.com/llvm/llvm-project/commit/8d06ef5658187bf6a3eda61a5ec3627c1ff33fb8
DIFF: https://github.com/llvm/llvm-project/commit/8d06ef5658187bf6a3eda61a5ec3627c1ff33fb8.diff

LOG: [LLDB] Check that RegisterInfo and ContextInfo are trivial

RegisterInfo is often initialised with a memcpy, and ContextInfo
does not run destructors for anything within it.

This was discussed in https://reviews.llvm.org/D134041.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D136584

Added: 
    

Modified: 
    lldb/include/lldb/Core/EmulateInstruction.h
    lldb/include/lldb/lldb-private-types.h

Removed: 
    


################################################################################
diff  --git a/lldb/include/lldb/Core/EmulateInstruction.h b/lldb/include/lldb/Core/EmulateInstruction.h
index 65b7982c36a0b..64633e9cf29be 100644
--- a/lldb/include/lldb/Core/EmulateInstruction.h
+++ b/lldb/include/lldb/Core/EmulateInstruction.h
@@ -189,7 +189,7 @@ class EmulateInstruction : public PluginInterface {
 
   public:
     enum InfoType GetInfoType() const { return info_type; }
-    union {
+    union ContextInfo {
       struct RegisterPlusOffset {
         RegisterInfo reg;      // base register
         int64_t signed_offset; // signed offset added to base register
@@ -241,6 +241,8 @@ class EmulateInstruction : public PluginInterface {
 
       uint32_t isa;
     } info;
+    static_assert(std::is_trivial<ContextInfo>::value,
+                  "ContextInfo must be trivial.");
 
     Context() = default;
 

diff  --git a/lldb/include/lldb/lldb-private-types.h b/lldb/include/lldb/lldb-private-types.h
index 1b0d263e2073b..edc1c78985bdd 100644
--- a/lldb/include/lldb/lldb-private-types.h
+++ b/lldb/include/lldb/lldb-private-types.h
@@ -15,6 +15,8 @@
 
 #include "llvm/ADT/ArrayRef.h"
 
+#include <type_traits>
+
 namespace llvm {
 namespace sys {
 class DynamicLibrary;
@@ -70,6 +72,8 @@ struct RegisterInfo {
                                           byte_size);
   }
 };
+static_assert(std::is_trivial<RegisterInfo>::value,
+              "RegisterInfo must be trivial.");
 
 /// Registers are grouped into register sets
 struct RegisterSet {