meson: Add support for using cmake for finding LLVM

Meson has support for using cmake as a finder for some dependencies,
including LLVM. Using cmake has a lot of advantages: it needs less meson
maintenance to keep working (even for llvm updates); it works more
sanely for cross compiles (as llvm-config is a compiled binary not a
shell script). Meson 0.51.0 also has a new generic variable getter that
can be used to get information from either cmake, pkg-config, or
config-tools dependencies, which is needed for cmake. We continue to
support using llvm-config if you don't have cmake installed, or if cmake
cannot find a suitable version.

Fixes: 0d59459432cf077d768164091318af8fb1612500
       ("meson: Force the use of config-tool for llvm")
Reviewed-by: Eric Engestrom <[email protected]>

1 files changed, 8 insertions, 5 deletions

diff --git a/src/gallium/drivers/swr/rasterizer/jitter/meson.build b/src/gallium/drivers/swr/rasterizer/jitter/meson.build
index aced4a1b735..6885c344939 100644
--- a/src/gallium/drivers/swr/rasterizer/jitter/meson.build
+++ b/src/gallium/drivers/swr/rasterizer/jitter/meson.build
@@ -1,4 +1,4 @@
-# Copyright © 2017-2018 Intel Corporation
+# Copyright © 2017-2019 Intel Corporation
 
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -19,14 +19,17 @@
 # SOFTWARE.
 
 
+if meson.version().version_compare('>=0.51')
+  _llvm_includedir = dep_llvm.get_variable(configtool : 'includedir', cmake : 'LLVM_INCLUDE_DIR')
+else
+  _llvm_includedir = dep_llvm.get_configtool_variable('includedir')
+endif
+
 gen_builder_hpp = custom_target(
   'gen_builder.hpp',
   input : [
     swr_gen_llvm_ir_macros_py,
-    join_paths(
-      dep_llvm.get_configtool_variable('includedir'), 'llvm', 'IR',
-      'IRBuilder.h'
-    )
+    join_paths(_llvm_includedir, 'llvm', 'IR', 'IRBuilder.h')
   ],
   output : 'gen_builder.hpp',
   command : [