llvm-project/lldb/packages/Python/lldbsuite/test/make/pseudo_barrier.h

#include <atomic>

// Note that although hogging the CPU while waiting for a variable to change
// would be terrible in production code, it's great for testing since it
// avoids a lot of messy context switching to get multiple threads synchronized.

typedef std::atomic<int> pseudo_barrier_t;
#define pseudo_barrier_wait(barrier)        \
    do                                      \
    {                                       \
        --(barrier);                        \
        while ((barrier).load() > 0)        \
            ;                               \
    } while (0)

#define pseudo_barrier_init(barrier, count) \
    do                                      \
    {                                       \
        (barrier) = (count);                \
    } while (0)
Centralize libc++ test skipping logic Summary: This aims to replace the different decorators we've had on each libc++ test with a single solution. Each libc++ will be assigned to the "libc++" category and a single central piece of code will decide whether we are actually able to run libc++ test in the given configuration by enabling or disabling the category (while giving the user the opportunity to override this). I started this effort because I wanted to get libc++ tests running on android, and none of the existing decorators worked for this use case: - skipIfGcc - incorrect, we can build libc++ executables on android with gcc (in fact, after this, we can now do it on linux as well) - lldbutil.skip_if_library_missing - this checks whether libc++.so is loaded in the proces, which fails in case of a statically linked libc++ (this makes copying executables to the remote target easier to manage). To make this work I needed to split out the pseudo_barrier code from the force-included file, as libc++'s atomic does not play well with gcc on linux, and this made every test fail, even though we need the code only in the threading tests. So far, I am only annotating one of the tests with this category. If this does not break anything, I'll proceed to update the rest. Reviewers: jingham, zturner, EricWF Subscribers: srhines, lldb-commits Differential Revision: https://reviews.llvm.org/D30984 llvm-svn: 299028 2017-03-30 05:01:14 +08:00			`#include <atomic>`

			`// Note that although hogging the CPU while waiting for a variable to change`
			`// would be terrible in production code, it's great for testing since it`
			`// avoids a lot of messy context switching to get multiple threads synchronized.`

			`typedef std::atomic<int> pseudo_barrier_t;`
			`#define pseudo_barrier_wait(barrier) \`
			`do \`
			`{ \`
			`--(barrier); \`
			`while ((barrier).load() > 0) \`
			`; \`
			`} while (0)`

			`#define pseudo_barrier_init(barrier, count) \`
			`do \`
			`{ \`
			`(barrier) = (count); \`
			`} while (0)`