Docs: minor fix to the benchmark code
Just realized the benchmark code was technically incorrect:
- 32-bit writes would mis-align 64-bit ones
- the storage itself was not guaranteed to be aligned
TBR: lalitm
Change-Id: Id39646a0a68c20367450672c9201f09b4c3ffe66
diff --git a/docs/design-docs/protozero.md b/docs/design-docs/protozero.md
index d77da48..fa87fe2 100644
--- a/docs/design-docs/protozero.md
+++ b/docs/design-docs/protozero.md
@@ -397,7 +397,7 @@
void Append(T x) {
// The memcpy will be elided by the compiler, which will emit just a
// 64-bit aligned mov instruction.
- memcpy(reinterpret_cast<T*>(ptr_), &x, sizeof(x));
+ memcpy(reinterpret_cast<void*>(ptr_), &x, sizeof(x));
ptr_ += sizeof(x);
}
@@ -407,7 +407,7 @@
void set_field_uint64(uint64_t x) { Append(x); }
void set_field_string(const char* str) { ptr_ = strcpy(ptr_, str); }
- char storage_[sizeof(g_fake_input_simple)];
+ alignas(uint64_t) char storage_[sizeof(g_fake_input_simple) + 8];
char* ptr_ = &storage_[0];
};
```
