scons: Tool for LLVM. Gracefully disable llvmpipe if LLVM not found.

scons/llvm.py

@@ -0,0 +1,81 @@
+"""llvm
+
+Tool-specific initialization for LLVM
+
+"""
+
+#
+# Copyright (c) 2009 VMware, Inc.
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and associated documentation files (the
+# "Software"), to deal in the Software without restriction, including
+# without limitation the rights to use, copy, modify, merge, publish,
+# distribute, sublicense, and/or sell copies of the Software, and to
+# permit persons to whom the Software is furnished to do so, subject to
+# the following conditions:
+#
+# The above copyright notice and this permission notice shall be included
+# in all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+#
+
+import os
+import os.path
+import subprocess
+
+import SCons.Action
+import SCons.Errors
+import SCons.Util
+
+
+def generate(env):
+    try:
+        llvm_dir = os.environ['LLVM']
+    except KeyError:
+        # Do nothing -- use the system headers/libs
+        pass
+    else:
+        if not os.path.isdir(llvm_dir):
+            raise SCons.Errors.InternalError, "Specified LLVM directory not found"
+
+        if env['debug']:
+            llvm_subdir = 'Debug'
+        else:
+            llvm_subdir = 'Release'
+
+        llvm_bin_dir = os.path.join(llvm_dir, llvm_subdir, 'bin')
+        if not os.path.isdir(llvm_bin_dir):
+            raise SCons.Errors.InternalError, "LLVM build directory not found"
+
+        env.PrependENVPath('PATH', llvm_bin_dir)
+
+    if env.Detect('llvm-config'):
+        pipe = SCons.Action._subproc(env, 
+                                     ['llvm-config', '--version'],
+                                     stdin = 'devnull',
+                                     stderr = 'devnull',
+                                     stdout = subprocess.PIPE)
+        if pipe.wait() != 0:
+            return
+        line = pipe.stdout.read().strip()
+        if not line:
+            return
+        env['LLVM_VERSION'] = line
+
+        env.ParseConfig('llvm-config --cppflags')
+        env.ParseConfig('llvm-config --libs jit interpreter nativecodegen bitwriter')
+        env.ParseConfig('llvm-config --ldflags')
+        env['LINK'] = env['CXX']
+
+def exists(env):
+    return True
+
+# vim:set ts=4 sw=4 et:

src/gallium/drivers/llvmpipe/SConscript

@@ -2,8 +2,12 @@ Import('*')
 
 env = env.Clone()
 
+env.Tool('llvm')
+if 'LLVM_VERSION' not in env:
+    print 'warning: LLVM not found: not building llvmpipe'
+    Return()
+
 env.Tool('udis86')
-env.ParseConfig('llvm-config --cppflags')
 
 llvmpipe = env.ConvenienceLibrary(
 	target = 'llvmpipe',
@@ -57,8 +61,6 @@ llvmpipe = env.ConvenienceLibrary(
 
 env = env.Clone()
 
-env['LINK'] = env['CXX']
-env.ParseConfig('llvm-config --libs jit interpreter nativecodegen bitwriter')
 env.Prepend(LIBS = [llvmpipe] + auxiliaries)
 
 env.Program(

src/gallium/winsys/xlib/SConscript

@@ -30,12 +30,12 @@ if env['platform'] == 'linux' \
         drivers += [softpipe]
 
     if 'llvmpipe' in env['drivers']:
-        env.Append(CPPDEFINES = 'GALLIUM_LLVMPIPE')
-        env.Tool('udis86')
-        env.ParseConfig('llvm-config --libs jit interpreter nativecodegen')
-        env['LINK'] = env['CXX']
-        sources += ['xlib_llvmpipe.c']
-        drivers += [llvmpipe]
+        env.Tool('llvm')
+        if 'LLVM_VERSION' in env:
+            env.Append(CPPDEFINES = 'GALLIUM_LLVMPIPE')
+            env.Tool('udis86')
+            sources += ['xlib_llvmpipe.c']
+            drivers += [llvmpipe]
 
     if 'i965simple' in env['drivers']:
         env.Append(CPPDEFINES = 'GALLIUM_I965SIMPLE')