[Mesa-dev] [RFC] opencl: mega-cl

[Rob Clark]

This is a sort of workaround for an issue encountered with the ongoing
work for clover clc->spirv->nir work for supporting OpenCL with drivers
that support consuming nir instead of llvm-ir.  The problem is that
libnir (and therefore glsl_types) ends up statically linked into both
clover and the pipe driver it dynamically loads.  Which causes *much*
hillarity.

An easy solution is to statically link the drivers into clover.  In fact
I'm not even really sure what other solution there is, but maybe there
is some linker magic I am not aware of.

(Note, if mesa state tracker ever used libpipe_loader_dynamic, I think
it would hit the same problem.  If we still support that config, we
should drop it ASAP.)

The down side is we end up statically linking in drivers and other
things that don't make sense (ie. only support TGSI or don't support
compute shaders, etc).  I'm thinking a sane option here is to have for
each driver, "driver_${name}" plus "driver_${name}_stub", the stub
containing an entry point that just returns an error.  (Maybe also do
similar for winsys and some other things?)  This way, a target like
opencl can pick either the real driver or the stub as needed.

Btw, I'm kinda thinking we should drop libpipe_loader_dynamic
completely, only only use libpipe_loader_static, and use the stub
drivers to avoid pulling in stuff that doesn't make sense.  (I noticed,
for example, the omx target statically links a bunch of drivers that
don't support the video related gallium APIs.. this stub driver approach
would help there too.)

Signed-off-by: Rob Clark <robdclark at gmail.com>
---
 src/gallium/targets/opencl/meson.build | 18 +++++++++++++++---
 src/gallium/targets/opencl/target.c    |  2 ++
 2 files changed, 17 insertions(+), 3 deletions(-)
 create mode 100644 src/gallium/targets/opencl/target.c

diff --git a/src/gallium/targets/opencl/meson.build b/src/gallium/targets/opencl/meson.build
index bebe0547d45..8d5fd81b55e 100644
--- a/src/gallium/targets/opencl/meson.build
+++ b/src/gallium/targets/opencl/meson.build
@@ -35,13 +35,19 @@ opencl_libname = with_opencl_icd ? 'MesaOpenCL' : 'OpenCL'
 
 libopencl = shared_library(
   opencl_libname,
-  [],
+  ['target.c'],
+  include_directories : [
+    inc_common, inc_util, inc_gallium_winsys, inc_gallium_drivers,
+  ],
   link_args : [ld_args_gc_sections, opencl_link_args],
   link_depends : opencl_link_deps,
   link_whole : libclover,
-  link_with : [libpipe_loader_dynamic, libgallium, libmesa_util],
+  link_with : [
+    libpipe_loader_static, libgallium, libmesa_util,
+    libgalliumvl, libws_null, libwsw, libswdri, libswkmsdri,
+  ],
   dependencies : [
-    dep_thread, dep_clock, dep_dl, dep_unwind, dep_elf, dep_expat,
+    dep_libdrm, dep_thread, dep_clock, dep_dl, dep_unwind, dep_elf, dep_expat,
     cpp.find_library('clangCodeGen', dirs : llvm_libdir),
     cpp.find_library('clangFrontendTool', dirs : llvm_libdir),
     cpp.find_library('clangFrontend', dirs : llvm_libdir),
@@ -54,6 +60,12 @@ libopencl = shared_library(
     cpp.find_library('clangEdit', dirs : llvm_libdir),
     cpp.find_library('clangLex', dirs : llvm_libdir),
     cpp.find_library('clangBasic', dirs : llvm_libdir),
+    # TODO only a small subset of these makes sense, but libpipe_loader_static
+    # depends on all.. maybe there is a way to have stub versions for the
+    # drivers which don't support OpenCL?
+    driver_swrast, driver_r300, driver_r600, driver_radeonsi, driver_nouveau,
+    driver_pl111, driver_vc4, driver_vc5, driver_freedreno, driver_etnaviv,
+    driver_imx, driver_i915, driver_svga, driver_virgl, driver_swr,
   ],
   version : opencl_version,
   install : true,
diff --git a/src/gallium/targets/opencl/target.c b/src/gallium/targets/opencl/target.c
new file mode 100644
index 00000000000..308e23bb4a0
--- /dev/null
+++ b/src/gallium/targets/opencl/target.c
@@ -0,0 +1,2 @@
+#include "target-helpers/drm_helper.h"
+#include "target-helpers/sw_helper.h"
-- 
2.14.3