[asan] Remove unneeded VirtualQuery from exception handler
We don't use the result of the query, and all tests pass if I remove it.
During startup, ASan spends a fair amount of time in this handler, and
the query is much more expensive than the call to commit the memory.
@@ -265,11 +265,6 @@ ShadowExceptionHandler(PEXCEPTION_POINTERS exception_pointers) {
// Determine the address of the page that is being accessed.
uptr page = RoundDownTo(addr, page_size);
- // Query the existing page.
- MEMORY_BASIC_INFORMATION mem_info = {};
- if (::VirtualQuery((LPVOID)page, &mem_info, sizeof(mem_info)) == 0)
- return EXCEPTION_CONTINUE_SEARCH;
-
// Commit the page.
uptr result =
(uptr)::VirtualAlloc((LPVOID)page, page_size, MEM_COMMIT, PAGE_READWRITE);
