Nearly all of our lldb-server tests have two flavours (lldb-server and
debugserver). Each of them is tagged with an appropriate decorator, and
each of them starts with a call to a matching "init" method. The init
calls are mandatory, and it's not possible to meaningfully combine them
with a different decorator.
This patch leverages the existing decorators to also tag the tests with
the appropriate debug server tag, similar to how we do with debug info
flavours. This allows us to make the "init" calls from inside the common
setUp method.
XFAIL nodefaultlib.cpp on darwin - the test does not pass there
XFAIL TestGdbRemoteMemoryAllocation on windows - memory is allocated
with incorrect permissions
This patch adds support for the _M and _m gdb-remote packets, which
(de)allocate memory in the inferior. This works by "injecting" a
m(un)map syscall into the inferior. This consists of:
- finding an executable page of memory
- writing the syscall opcode to it
- setting up registers according to the os syscall convention
- single stepping over the syscall
The advantage of this approach over calling the mmap function is that
this works even in case the mmap function is buggy or unavailable. The
disadvantage is it is more platform-dependent, which is why this patch
only works on X86 (_32 and _64) right now. Adding support for other
linux architectures should be easy and consist of defining the
appropriate syscall constants. Adding support for other OSes depends on
the its ability to do a similar trick.
Differential Revision: https://reviews.llvm.org/D89124
Pavel Labath