llvm-build: Add --configure-target-def-file option.

 - Can be used to generate the substitution values we currently use for the various target related .def files.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144345 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 115 insertions, 9 deletions

diff --git a/utils/llvm-build/llvmbuild/configutil.py b/utils/llvm-build/llvmbuild/configutil.py
new file mode 100644
index 0000000000..b5582c34de
--- /dev/null
+++ b/utils/llvm-build/llvmbuild/configutil.py
@@ -0,0 +1,66 @@
+"""
+Defines utilities useful for performing standard "configuration" style tasks.
+"""
+
+import re
+import os
+
+def configure_file(input_path, output_path, substitutions):
+    """configure_file(input_path, output_path, substitutions) -> bool
+
+    Given an input and output path, "configure" the file at the given input path
+    by replacing variables in the file with those given in the substitutions
+    list. Returns true if the output file was written.
+
+    The substitutions list should be given as a list of tuples (regex string,
+    replacement), where the regex and replacement will be used as in 're.sub' to
+    execute the variable replacement.
+
+    The output path's parent directory need not exist (it will be created).
+
+    If the output path does exist and the configured data is not different than
+    it's current contents, the output file will not be modified. This is
+    designed to limit the impact of configured files on build dependencies.
+    """
+
+    # Read in the input data.
+    f = open(input_path, "rb")
+    try:
+        data = f.read()
+    finally:
+        f.close()
+
+    # Perform the substitutions.
+    for regex_string,replacement in substitutions:
+        regex = re.compile(regex_string)
+        data = regex.sub(replacement, data)
+
+    # Ensure the output parent directory exists.
+    output_parent_path = os.path.dirname(os.path.abspath(output_path))
+    if not os.path.exists(output_parent_path):
+        os.makedirs(output_parent_path)
+
+    # If the output path exists, load it and compare to the configured contents.
+    if os.path.exists(output_path):
+        current_data = None
+        try:
+            f = open(output_path, "rb")
+            try:
+                current_data = f.read()
+            except:
+                current_data = None
+            f.close()
+        except:
+            current_data = None
+
+        if current_data is not None and current_data == data:
+            return False
+
+    # Write the output contents.
+    f = open(output_path, "wb")
+    try:
+        f.write(data)
+    finally:
+        f.close()
+
+    return True
diff --git a/utils/llvm-build/llvmbuild/main.py b/utils/llvm-build/llvmbuild/main.py
index 51923ebad7..fa76aa5d8e 100644
--- a/utils/llvm-build/llvmbuild/main.py
+++ b/utils/llvm-build/llvmbuild/main.py
@@ -2,6 +2,7 @@ import os
 import sys
 
 import componentinfo
+import configutil
 
 from util import *
 
@@ -616,6 +617,9 @@ def main():
                      help=(
             "If given, an alternate path to search for LLVMBuild.txt files"),
                      action="store", default=None, metavar="PATH")
+    group.add_option("", "--build-root", dest="build_root", metavar="PATH",
+                      help="Path to the build directory (if needed) [%default]",
+                      action="store", default=None)
     parser.add_option_group(group)
 
     group = OptionGroup(parser, "Output Options")
@@ -637,6 +641,14 @@ def main():
                       dest="write_make_fragment", metavar="PATH",
                      help="Write the Makefile project information to PATH",
                      action="store", default=None)
+    group.add_option("", "--configure-target-def-file",
+                     dest="configure_target_def_files",
+                     help="""Configure the given file at SUBPATH (relative to
+the inferred or given source root, and with a '.in' suffix) by replacing certain
+substitution variables with lists of targets that support certain features (for
+example, targets with AsmPrinters) and write the result to the build root (as
+given by --build-root) at the same SUBPATH""",
+                     metavar="SUBPATH", action="append", default=None)
     parser.add_option_group(group)
 
     group = OptionGroup(parser, "Configuration Options")
@@ -701,5 +713,40 @@ def main():
     if opts.write_cmake_fragment:
         project_info.write_cmake_fragment(opts.write_cmake_fragment)
 
+    # Configure target definition files, if requested.
+    if opts.configure_target_def_files:
+        # Verify we were given a build root.
+        if not opts.build_root:
+            parser.error("must specify --build-root when using "
+                         "--configure-target-def-file")
+
+        # Create the substitution list.
+        available_targets = [ci for ci in project_info.component_infos
+                             if ci.type_name == 'TargetGroup']
+        substitutions = [
+            ("@LLVM_ENUM_TARGETS@",
+             ' '.join('LLVM_TARGET(%s)' % ci.name
+                      for ci in available_targets)),
+            ("@LLVM_ENUM_ASM_PRINTERS@",
+             ' '.join('LLVM_ASM_PRINTER(%s)' % ci.name
+                      for ci in available_targets
+                      if ci.has_asmprinter)),
+            ("@LLVM_ENUM_ASM_PARSERS@",
+             ' '.join('LLVM_ASM_PARSER(%s)' % ci.name
+                      for ci in available_targets
+                      if ci.has_asmparser)),
+            ("@LLVM_ENUM_DISASSEMBLERS@",
+             ' '.join('LLVM_DISASSEMBLER(%s)' % ci.name
+                      for ci in available_targets
+                      if ci.has_disassembler))]
+
+        # Configure the given files.
+        for subpath in opts.configure_target_def_files:
+            inpath = os.path.join(source_root, subpath + '.in')
+            outpath = os.path.join(opts.build_root, subpath)
+            result = configutil.configure_file(inpath, outpath, substitutions)
+            if not result:
+                note("configured file %r hasn't changed" % outpath)
+
 if __name__=='__main__':
     main()
diff --git a/utils/llvm-build/llvmbuild/util.py b/utils/llvm-build/llvmbuild/util.py
index cf6fa28573..e581af23d4 100644
--- a/utils/llvm-build/llvmbuild/util.py
+++ b/utils/llvm-build/llvmbuild/util.py
@@ -1,16 +1,9 @@
-import inspect
 import os
 import sys
 
 def _write_message(kind, message):
-    # Get the file/line where this message was generated.
-    f = inspect.currentframe()
-    # Step out of _write_message, and then out of wrapper.
-    f = f.f_back.f_back
-    file,line,_,_,_ = inspect.getframeinfo(f)
-    location = '%s:%d' % (os.path.basename(file), line)
-
-    print >>sys.stderr, '%s: %s: %s' % (location, kind, message)
+    program = os.path.basename(sys.argv[0])
+    print >>sys.stderr, '%s: %s: %s' % (program, kind, message)
 
 note = lambda message: _write_message('note', message)
 warning = lambda message: _write_message('warning', message)