testsuite: introduce 'static_stats' tests

They are a particular type of perf tests. This patch introduces a
'stats_files_dir' configuration field in the testsuite driver where all
haddock timing files (and possibly others in the future) are assumed to live.
We also change both the Make and Hadrian build systems to pass respectively
$(TOP)/testsuite/tests/perf/haddock/ and
<build root>/stage1/haddock-timing-files/ as the value of that new
configuration field, and to generate the timing files in those directories
in the first place while generating documentation with haddock.

This new test type can be seen as one dedicated to examining stats files that
are generated while building a GHC distribution. This also lets us get rid of
the 'extra_files' directives in the all.T entries for haddock.base,
haddock.Cabal and haddock.compiler.

5 files changed, 19 insertions, 4 deletions

diff --git a/hadrian/src/Context.hs b/hadrian/src/Context.hs
index 7c7bb124ff..0676743ee5 100644
--- a/hadrian/src/Context.hs
+++ b/hadrian/src/Context.hs
@@ -8,7 +8,8 @@ module Context (
     -- * Paths
     contextDir, buildPath, buildDir, pkgInplaceConfig, pkgSetupConfigFile,
     pkgHaddockFile, pkgRegisteredLibraryFile, pkgLibraryFile, pkgGhciLibraryFile,
-    pkgConfFile, objectPath, contextPath, getContextPath, libPath, distDir
+    pkgConfFile, objectPath, contextPath, getContextPath, libPath, distDir,
+    haddockStatsFilesDir
     ) where
 
 import Base
diff --git a/hadrian/src/Context/Path.hs b/hadrian/src/Context/Path.hs
index 4bc9d9be34..e5a82710ab 100644
--- a/hadrian/src/Context/Path.hs
+++ b/hadrian/src/Context/Path.hs
@@ -41,3 +41,8 @@ buildPath context = buildRoot <&> (-/- buildDir context)
 -- | The expression that evaluates to the build path of the current 'Context'.
 getBuildPath :: Expr Context b FilePath
 getBuildPath = expr . buildPath =<< getContext
+
+-- | Path to the directory containing haddock timing files, used by
+--   the haddock perf tests.
+haddockStatsFilesDir :: Action FilePath
+haddockStatsFilesDir = (-/- "stage1" -/- "haddock-timing-files") <$> buildRoot
diff --git a/hadrian/src/Rules/Documentation.hs b/hadrian/src/Rules/Documentation.hs
index a70b4d5c9d..9991f01708 100644
--- a/hadrian/src/Rules/Documentation.hs
+++ b/hadrian/src/Rules/Documentation.hs
@@ -205,7 +205,12 @@ buildPackageDocumentation = do
         -- TODO: Pass the correct way from Rules via Context.
         dynamicPrograms <- dynamicGhcPrograms =<< flavour
         let haddockWay = if dynamicPrograms then dynamic else vanilla
+        statsFilesDir <- haddockStatsFilesDir
+        createDirectory statsFilesDir
         build $ target (context {way = haddockWay}) (Haddock BuildPackage) srcs [file]
+        produces [
+          statsFilesDir </> pkgName (Context.package context) <.> "t"
+          ]
 
 data PkgDocTarget = DotHaddock PackageName | HaddockPrologue PackageName
   deriving (Eq, Show)
diff --git a/hadrian/src/Settings/Builders/Haddock.hs b/hadrian/src/Settings/Builders/Haddock.hs
index 65c703160c..b01b8a2459 100644
--- a/hadrian/src/Settings/Builders/Haddock.hs
+++ b/hadrian/src/Settings/Builders/Haddock.hs
@@ -35,13 +35,13 @@ haddockBuilderArgs = mconcat
         output   <- getOutput
         pkg      <- getPackage
         root     <- getBuildRoot
-        path     <- getBuildPath
         context  <- getContext
         version  <- expr $ pkgVersion  pkg
         synopsis <- expr $ pkgSynopsis pkg
         deps     <- getContextData depNames
         haddocks <- expr $ haddockDependencies context
         hVersion <- expr $ pkgVersion haddock
+        statsDir <- expr $ haddockStatsFilesDir
         ghcOpts  <- haddockGhcArgs
         mconcat
             [ arg "--verbosity=0"
@@ -66,6 +66,6 @@ haddockBuilderArgs = mconcat
             , pure [ "--optghc=" ++ opt | opt <- ghcOpts, not ("--package-db" `isInfixOf` opt) ]
             , getInputs
             , arg "+RTS"
-            , arg $ "-t" ++ path -/- "haddock.t"
+            , arg $ "-t" ++ (statsDir -/- pkgName pkg ++ ".t")
             , arg "--machine-readable"
             , arg "-RTS" ] ]
diff --git a/hadrian/src/Settings/Builders/RunTest.hs b/hadrian/src/Settings/Builders/RunTest.hs
index 6cc11f8aef..63e3dfd6c9 100644
--- a/hadrian/src/Settings/Builders/RunTest.hs
+++ b/hadrian/src/Settings/Builders/RunTest.hs
@@ -85,11 +85,14 @@ runTestBuilderArgs = builder RunTest ? do
     wordsize    <- getTestSetting TestWORDSIZE
     top         <- expr $ topDirectory
     ghcFlags    <- expr runTestGhcFlags
-    timeoutProg <- expr buildRoot <&> (-/- timeoutPath)
     cmdrootdirs <- expr (testRootDirs <$> userSetting defaultTestArgs)
     let defaultRootdirs = ("testsuite" -/- "tests") : libTests
         rootdirs | null cmdrootdirs = defaultRootdirs
                  | otherwise        = cmdrootdirs
+    root        <- expr buildRoot
+    let timeoutProg = root -/- timeoutPath
+    statsFilesDir <- expr haddockStatsFilesDir
+
     -- See #16087
     let ghcBuiltByLlvm = False -- TODO: Implement this check
 
@@ -134,6 +137,7 @@ runTestBuilderArgs = builder RunTest ? do
 
             , arg "--config", arg $ "gs=gs"                           -- Use the default value as in test.mk
             , arg "--config", arg $ "timeout_prog=" ++ show (top -/- timeoutProg)
+            , arg "--config", arg $ "stats_files_dir=" ++ statsFilesDir
             , arg $ "--threads=" ++ show threads
             , getTestArgs -- User-provided arguments from command line.
             ]