1 files changed, 24 insertions, 12 deletions
diff --git a/testsuite/tests/perf/haddock/all.T b/testsuite/tests/perf/haddock/all.T
index fca30366f9..929a7fd972 100644
--- a/testsuite/tests/perf/haddock/all.T
+++ b/testsuite/tests/perf/haddock/all.T
@@ -1,27 +1,39 @@
+# Note [Haddock runtime stats files]
+#
+# When one of the build systems builds a complete GHC distribution,
+# haddock gets built and then used to generate .haddock files for each
+# library. For that last step, both build systems pass an extra
+# `+RTS -t<some path>.t` to record runtime statistics to the given path.
+#
+# Those .t files are then used by a few haddock perf tests (which all live
+# under testsuite/tests/perf/haddock/). Since each build system needs to produce
+# those files in different places, the testsuite driver takes the directory
+# under which those files are placed as a configuration parameter,
+# `config.stats_files_dir`. Each individual test then specifies the name of
+# the (runtime statistics) file against which some checks are to be performed,
+# in addition to declaring the test's type to be `static_stats`.
+
 # We do not add peak_megabytes_allocated and max_bytes_used to these tests, as
 # they are somewhat unreliable, and it is harder to re-run these numbers to
 # detect outliers, as described in Note [residency]. See #9556.
 
 test('haddock.base',
-     [extra_files(['../../../../libraries/base/dist-install/haddock.t']),
-      unless(in_tree_compiler(), skip), req_haddock
+     [unless(in_tree_compiler(), skip), req_haddock
      ,collect_stats('bytes allocated',5)
       ],
-     stats,
-     ['haddock.t'])
+     static_stats,
+     ['base.t'])
 
 test('haddock.Cabal',
-     [extra_files(['../../../../libraries/Cabal/Cabal/dist-install/haddock.t']),
-      unless(in_tree_compiler(), skip), req_haddock
+     [unless(in_tree_compiler(), skip), req_haddock
      ,collect_stats('bytes allocated',5)
       ],
-     stats,
-     ['haddock.t'])
+     static_stats,
+     ['Cabal.t'])
 
 test('haddock.compiler',
-     [extra_files(['../../../../compiler/stage2/haddock.t']),
-      unless(in_tree_compiler(), skip), req_haddock
+     [unless(in_tree_compiler(), skip), req_haddock
      ,collect_stats('bytes allocated',10)
       ],
-     stats,
-     ['haddock.t'])
+     static_stats,
+     ['ghc.t'])