Fix UBSAN warnings in masm

Change-Id: Ie86307fe55fce957adf48e9861022fddfa3d7374
Reviewed-by: Simon Hausmann <simon.hausmann@qt.io>

2 files changed, 19 insertions, 3 deletions

diff --git a/src/3rdparty/masm/assembler/AssemblerBuffer.h b/src/3rdparty/masm/assembler/AssemblerBuffer.h
index 277ec1043c..45874235b6 100644
--- a/src/3rdparty/masm/assembler/AssemblerBuffer.h
+++ b/src/3rdparty/masm/assembler/AssemblerBuffer.h
@@ -102,7 +102,7 @@ namespace JSC {
         void putIntegralUnchecked(IntegralType value)
         {
             ASSERT(isAvailable(sizeof(IntegralType)));
-            *reinterpret_cast_ptr<IntegralType*>(m_buffer + m_index) = value;
+            memcpy(m_buffer + m_index, &value, sizeof(IntegralType));
             m_index += sizeof(IntegralType);
         }
 
diff --git a/src/3rdparty/masm/assembler/X86Assembler.h b/src/3rdparty/masm/assembler/X86Assembler.h
index b71cf290f8..6fa66e0dd7 100644
--- a/src/3rdparty/masm/assembler/X86Assembler.h
+++ b/src/3rdparty/masm/assembler/X86Assembler.h
@@ -1892,9 +1892,18 @@ public:
         ASSERT(to.isSet());
 
         char* code = reinterpret_cast<char*>(m_formatter.data());
-        ASSERT(!reinterpret_cast<int32_t*>(code + from.m_offset)[-1]);
+        ASSERT(!loadPossiblyUnaligned<int32_t>(code, from.m_offset, -1));
         setRel32(code + from.m_offset, code + to.m_offset);
     }
+
+    template<typename T>
+    T loadPossiblyUnaligned(char *ptr, size_t offset, int idx)
+    {
+        T *t_ptr = &reinterpret_cast<T*>(ptr + offset)[idx];
+        T val;
+        memcpy(&val, t_ptr, sizeof(T));
+        return val;
+    }
     
     static void linkJump(void* code, AssemblerLabel from, void* to)
     {
@@ -2095,7 +2104,14 @@ private:
 
     static void setInt32(void* where, int32_t value)
     {
-        reinterpret_cast<int32_t*>(where)[-1] = value;
+        storePossiblyUnaligned<int32_t>(where, -1, value);
+    }
+
+    template <typename T>
+    static void storePossiblyUnaligned(void *where, int idx, T value)
+    {
+        T *ptr = &reinterpret_cast<T*>(where)[idx];
+        memcpy(ptr, &value, sizeof(T));
     }
     
     static void setInt8(void* where, int8_t value)