1*dc213305SDaniel Sanders========================================
2*dc213305SDaniel SandersCompiler-rt Testing Infrastructure Guide
3*dc213305SDaniel Sanders========================================
4*dc213305SDaniel Sanders
5*dc213305SDaniel Sanders.. contents::
6*dc213305SDaniel Sanders   :local:
7*dc213305SDaniel Sanders
8*dc213305SDaniel SandersOverview
9*dc213305SDaniel Sanders========
10*dc213305SDaniel Sanders
11*dc213305SDaniel SandersThis document is the reference manual for the compiler-rt modifications to the
12*dc213305SDaniel Sanderstesting infrastructure. Documentation for the infrastructure itself can be found at
13*dc213305SDaniel Sanders:ref:`llvm_testing_guide`.
14*dc213305SDaniel Sanders
15*dc213305SDaniel SandersLLVM testing infrastructure organization
16*dc213305SDaniel Sanders========================================
17*dc213305SDaniel Sanders
18*dc213305SDaniel SandersThe compiler-rt testing infrastructure contains regression tests which are run
19*dc213305SDaniel Sandersas part of the usual ``make check-all`` and are expected to always pass -- they
20*dc213305SDaniel Sandersshould be run before every commit.
21*dc213305SDaniel Sanders
22*dc213305SDaniel SandersQuick start
23*dc213305SDaniel Sanders===========
24*dc213305SDaniel Sanders
25*dc213305SDaniel SandersThe regressions tests are in the "compiler-rt" module and are normally checked
26*dc213305SDaniel Sandersout in the directory ``llvm/projects/compiler-rt/test``. Use ``make check-all``
27*dc213305SDaniel Sandersto run the regression tests after building compiler-rt.
28*dc213305SDaniel Sanders
29*dc213305SDaniel SandersREQUIRES, XFAIL, etc.
30*dc213305SDaniel Sanders---------------------
31*dc213305SDaniel Sanders
32*dc213305SDaniel SandersSometimes it is necessary to restrict a test to a specific target or mark it as
33*dc213305SDaniel Sandersan "expected fail" or XFAIL. This is normally achieved using ``REQUIRES:`` or
34*dc213305SDaniel Sanders``XFAIL:`` with a substring of LLVM's default target triple. Unfortunately, the
35*dc213305SDaniel Sandersbehaviour of this is somewhat quirky in compiler-rt. There are two main
36*dc213305SDaniel Sanderspitfalls to avoid.
37*dc213305SDaniel Sanders
38*dc213305SDaniel SandersThe first pitfall is that these directives perform a substring match on the
39*dc213305SDaniel Sanderstriple and as such ``XFAIL: mips`` affects more triples than expected. For
40*dc213305SDaniel Sandersexample, ``mips-linux-gnu``, ``mipsel-linux-gnu``, ``mips64-linux-gnu``, and
41*dc213305SDaniel Sanders``mips64el-linux-gnu`` will all match a ``XFAIL: mips`` directive. Including a
42*dc213305SDaniel Sanderstrailing ``-`` such as in ``XFAIL: mips-`` can help to mitigate this quirk but
43*dc213305SDaniel Sanderseven that has issues as described below.
44*dc213305SDaniel Sanders
45*dc213305SDaniel SandersThe second pitfall is that the default target triple is often inappropriate for
46*dc213305SDaniel Sanderscompiler-rt tests since compiler-rt tests may be compiled for multiple targets.
47*dc213305SDaniel SandersFor example, a typical build on an ``x86_64-linux-gnu`` host will often run the
48*dc213305SDaniel Sanderstests for both x86_64 and i386. In this situation ``XFAIL: x86_64`` will mark
49*dc213305SDaniel Sandersboth the x86_64 and i386 tests as an expected failure while ``XFAIL: i386``
50*dc213305SDaniel Sanderswill have no effect at all.
51*dc213305SDaniel Sanders
52*dc213305SDaniel SandersTo remedy both pitfalls, compiler-rt tests provide a feature string which can
53*dc213305SDaniel Sandersbe used to specify a single target. This string is of the form
54*dc213305SDaniel Sanders``target-is-${arch}`` where ``${arch}}`` is one of the values from the
55*dc213305SDaniel Sandersfollowing lines of the CMake output::
56*dc213305SDaniel Sanders
57*dc213305SDaniel Sanders  -- Compiler-RT supported architectures: x86_64;i386
58*dc213305SDaniel Sanders  -- Builtin supported architectures: i386;x86_64
59*dc213305SDaniel Sanders
60*dc213305SDaniel SandersSo for example ``XFAIL: target-is-x86_64`` will mark a test as expected to fail
61*dc213305SDaniel Sanderson x86_64 without also affecting the i386 test and ``XFAIL: target-is-i386``
62*dc213305SDaniel Sanderswill mark a test as expected to fail on i386 even if the default target triple
63*dc213305SDaniel Sandersis ``x86_64-linux-gnu``. Directives that use these ``target-is-${arch}`` string
64*dc213305SDaniel Sandersrequire exact matches so ``XFAIL: target-is-mips``,
65*dc213305SDaniel Sanders``XFAIL: target-is-mipsel``, ``XFAIL: target-is-mips64``, and
66*dc213305SDaniel Sanders``XFAIL: target-is-mips64el`` all refer to different MIPS targets.
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