[lit] Improve tool substitution in lit.

This addresses two sources of inconsistency in test configuration
files.

1. Substitution boundaries.  Previously you would specify a
   substitution, such as 'lli', and then additionally a set
   of characters that should fail to match before and after
   the tool.  This was used, for example, so that matches that
   are parts of full paths would not be replaced.  But not all
   tools did this, and those that did would often re-invent
   the set of characters themselves, leading to inconsistency.
   Now, every tool substitution defaults to using a sane set
   of reasonable defaults and you have to explicitly opt out
   of it.  This actually fixed a few latent bugs that were
   never being surfaced, but only on accident.

2. There was no standard way for the system to decide how to
   locate a tool.  Sometimes you have an explicit path, sometimes
   we would search for it and build up a path ourselves, and
   sometimes we would build up a full command line.  Furthermore,
   there was no standardized way to handle missing tools.  Do we
   warn, fail, ignore, etc?  All of this is now encapsulated in
   the ToolSubst class.  You either specify an exact command to
   run, or an instance of FindTool('<tool-name>') and everything
   else just works.  Furthermore, you can specify an action to
   take if the tool cannot be resolved.

Differential Revision: https://reviews.llvm.org/D38565

llvm-svn: 315085

1 files changed, 52 insertions, 67 deletions

diff --git a/llvm/test/lit.cfg.py b/llvm/test/lit.cfg.py
index 26a394f7878..7b935c19558 100644
--- a/llvm/test/lit.cfg.py
+++ b/llvm/test/lit.cfg.py
@@ -11,7 +11,8 @@ import subprocess
 import lit.util
 import lit.formats
 from lit.llvm import llvm_config
-from lit.llvm import ToolFilter
+from lit.llvm.subst import FindTool
+from lit.llvm.subst import ToolSubst
 
 # name: The name of this test suite.
 config.name = 'LLVM'
@@ -82,31 +83,30 @@ def get_asan_rtlib():
     return found_dylibs[0]
 
 
-lli = 'lli'
+llvm_config.use_default_substitutions()
+
+# Add site-specific substitutions.
+config.substitutions.append(('%llvmshlibdir', config.llvm_shlib_dir))
+config.substitutions.append(('%shlibext', config.llvm_shlib_ext))
+config.substitutions.append(('%exeext', config.llvm_exe_ext))
+config.substitutions.append(('%host_cc', config.host_cc))
+
+
+lli_args = []
 # The target triple used by default by lli is the process target triple (some
 # triple appropriate for generating code for the current process) but because
 # we don't support COFF in MCJIT well enough for the tests, force ELF format on
 # Windows.  FIXME: the process target triple should be used here, but this is
 # difficult to obtain on Windows.
 if re.search(r'cygwin|mingw32|windows-gnu|windows-msvc|win32', config.host_triple):
-    lli += ' -mtriple=' + config.host_triple + '-elf'
-config.substitutions.append(('%lli', lli))
+    lli_args = ['-mtriple=' + config.host_triple + '-elf']
+
+llc_args = []
 
 # Similarly, have a macro to use llc with DWARF even when the host is win32.
-llc_dwarf = 'llc'
 if re.search(r'win32', config.target_triple):
-    llc_dwarf += ' -mtriple=' + \
-        config.target_triple.replace('-win32', '-mingw32')
-config.substitutions.append(('%llc_dwarf', llc_dwarf))
-
-# Add site-specific substitutions.
-config.substitutions.append(('%gold', config.gold_executable))
-config.substitutions.append(('%go', config.go_executable))
-config.substitutions.append(('%llvmshlibdir', config.llvm_shlib_dir))
-config.substitutions.append(('%shlibext', config.llvm_shlib_ext))
-config.substitutions.append(('%exeext', config.llvm_exe_ext))
-config.substitutions.append(('%python', config.python_executable))
-config.substitutions.append(('%host_cc', config.host_cc))
+    llc_args = [' -mtriple=' +
+                config.target_triple.replace('-win32', '-mingw32')]
 
 # Provide the path to asan runtime lib if available. On darwin, this lib needs
 # to be loaded via DYLD_INSERT_LIBRARIES before libLTO.dylib in case the files
@@ -115,36 +115,28 @@ ld64_cmd = config.ld64_executable
 asan_rtlib = get_asan_rtlib()
 if asan_rtlib:
     ld64_cmd = 'DYLD_INSERT_LIBRARIES={} {}'.format(asan_rtlib, ld64_cmd)
-config.substitutions.append(('%ld64', ld64_cmd))
 
-# OCaml substitutions.
-# Support tests for both native and bytecode builds.
-config.substitutions.append(('%ocamlc',
-                             '%s ocamlc -cclib -L%s %s' %
-                             (config.ocamlfind_executable, config.llvm_lib_dir, config.ocaml_flags)))
+ocamlc_command = '%s ocamlc -cclib -L%s %s' % (
+    config.ocamlfind_executable, config.llvm_lib_dir, config.ocaml_flags)
+ocamlopt_command = 'true'
 if config.have_ocamlopt:
-    config.substitutions.append(('%ocamlopt',
-                                 '%s ocamlopt -cclib -L%s -cclib -Wl,-rpath,%s %s' %
-                                 (config.ocamlfind_executable, config.llvm_lib_dir, config.llvm_lib_dir, config.ocaml_flags)))
-else:
-    config.substitutions.append(('%ocamlopt', 'true'))
-
-# For each occurrence of an llvm tool name as its own word, replace it
-# with the full path to the build directory holding that tool.  This
-# ensures that we are testing the tools just built and not some random
-# tools that might happen to be in the user's PATH.  Thus this list
-# includes every tool placed in $(LLVM_OBJ_ROOT)/$(BuildMode)/bin
-# (llvm_tools_dir in lit parlance).
-
-# Avoid matching RUN line fragments that are actually part of
-# path names or options or whatever.
-# The regex is a pre-assertion to avoid matching a preceding
-# dot, hyphen, carat, or slash (.foo, -foo, etc.).  Some patterns
-# also have a post-assertion to not match a trailing hyphen (foo-).
-JUNKCHARS = r".-^/<"
-
-required_tools = [
-    'lli', 'llvm-ar', 'llvm-as', 'llvm-bcanalyzer', 'llvm-config', 'llvm-cov',
+    ocamlopt_command = '%s ocamlopt -cclib -L%s -cclib -Wl,-rpath,%s %s' % (
+        config.ocamlfind_executable, config.llvm_lib_dir, config.llvm_lib_dir, config.ocaml_flags)
+
+
+tools = [
+    ToolSubst('%lli', FindTool('lli'), post='.', extra_args=lli_args),
+    ToolSubst('%llc_dwarf', FindTool('llc'), extra_args=llc_args),
+    ToolSubst('%go', config.go_executable, unresolved='ignore'),
+    ToolSubst('%gold', config.gold_executable, unresolved='ignore'),
+    ToolSubst('%ld64', ld64_cmd, unresolved='ignore'),
+    ToolSubst('%ocamlc', ocamlc_command, unresolved='ignore'),
+    ToolSubst('%ocamlopt', ocamlopt_command, unresolved='ignore'),
+]
+
+# FIXME: Why do we have both `lli` and `%lli` that do slightly different things?
+tools.extend([
+    'lli', 'lli-child-target', 'llvm-ar', 'llvm-as', 'llvm-bcanalyzer', 'llvm-config', 'llvm-cov',
     'llvm-cxxdump', 'llvm-cvtres', 'llvm-diff', 'llvm-dis', 'llvm-dsymutil',
     'llvm-dwarfdump', 'llvm-extract', 'llvm-isel-fuzzer', 'llvm-lib',
     'llvm-link', 'llvm-lto', 'llvm-lto2', 'llvm-mc', 'llvm-mcmarkup',
@@ -152,28 +144,21 @@ required_tools = [
     'llvm-pdbutil', 'llvm-profdata', 'llvm-ranlib', 'llvm-readobj',
     'llvm-rtdyld', 'llvm-size', 'llvm-split', 'llvm-strings', 'llvm-tblgen',
     'llvm-c-test', 'llvm-cxxfilt', 'llvm-xray', 'yaml2obj', 'obj2yaml',
-    'FileCheck', 'yaml-bench', 'verify-uselistorder',
-    ToolFilter('bugpoint', post='-'),
-    ToolFilter('llc', pre=JUNKCHARS),
-    ToolFilter('llvm-symbolizer', pre=JUNKCHARS),
-    ToolFilter('opt', JUNKCHARS),
-    ToolFilter('sancov', pre=JUNKCHARS),
-    ToolFilter('sanstats', pre=JUNKCHARS),
-    # Handle these specially as they are strings searched for during testing.
-    ToolFilter(r'\| \bcount\b', verbatim=True),
-    ToolFilter(r'\| \bnot\b', verbatim=True)]
-
-llvm_config.add_tool_substitutions(required_tools, config.llvm_tools_dir)
-
-# For tools that are optional depending on the config, we won't warn
-# if they're missing.
-
-optional_tools = [
-    'llvm-go', 'llvm-mt', 'Kaleidoscope-Ch3', 'Kaleidoscope-Ch4',
-    'Kaleidoscope-Ch5', 'Kaleidoscope-Ch6', 'Kaleidoscope-Ch7',
-    'Kaleidoscope-Ch8']
-llvm_config.add_tool_substitutions(optional_tools, config.llvm_tools_dir,
-                                   warn_missing=False)
+    'yaml-bench', 'verify-uselistorder',
+    'bugpoint', 'llc', 'llvm-symbolizer', 'opt', 'sancov', 'sanstats'])
+
+# The following tools are optional
+tools.extend([
+    ToolSubst('llvm-go', unresolved='ignore'),
+    ToolSubst('llvm-mt', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch3', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch4', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch5', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch6', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch7', unresolved='ignore'),
+    ToolSubst('Kaleidoscope-Ch8', unresolved='ignore')])
+
+llvm_config.add_tool_substitutions(tools, config.llvm_tools_dir)
 
 # Targets