Done so far is:
-- TGSI -> LLVM fragment shader translation
- - same level of support as the TGSI SSE2 exec machine
- - texture sampling via an intrinsic call
- - done in SoA
- - input interpolation also code generated
+ - the whole fragment pipeline is code generated in a single function
+
+ - input interpolation
+
+ - depth testing
+
+ - texture sampling (not all state/formats are supported)
+
+ - fragment shader TGSI translation
+ - same level of support as the TGSI SSE2 exec machine, with the exception
+ we don't fallback to TGSI interpretation when an unsupported opcode is
+ found, but just ignore it
+ - done in SoA layout
+ - input interpolation also code generated
+
+ - alpha testing
+
+ - blend (including logic ops)
+ - both in SoA and AoS layouts, but only the former used for now
+
+ - code is generic
+ - intermediates can be vectors of floats, ubytes, fixed point, etc, and of
+ any width and length
+ - not all operations are implemented for these types yet though
-- blend -> LLVM (including logic ops)
- - SoA and AoS, but only the former used
+Most mesa/progs/demos/* work.
-- code is generic
- - intermediates can be vectors of floats, ubytes, fixed point, etc, and of
- any width and length
- - not all operations are implemented for these types yet though
+To do (probably by this order):
-Most mesa/progs/demos/* work. Speed is on par with Keith's softpipe-opt branch,
-which includes hand written fast implementations for common cases.
+ - code generate stipple and stencil testing
-To do (probably by this order):
-- code generate the rest of the fragment pipeline, namely the
- depth/alpha/stencil state
-- concatenate the fragment pipeline (shader + depth/stencil/alpha + blend) in a
- single function
-- code generate texture sampling
-- translate TGSI control flow instructions
-- code generate the triangle setup and rasterization
+ - translate the remaining bits of texture sampling state
+
+ - translate TGSI control flow instructions, and all other remaining opcodes
+
+ - integrate with the draw module for VS code generation
+
+ - code generate the triangle setup and rasterization
Requirements
instructions. This is necessary because we emit several SSE intrinsics for
convenience. See /proc/cpuinfo to know what your CPU supports.
- - scons (although it should be straightforward to fix the Makefiles as well)
+ - scons
Building
scons debug=yes statetrackers=mesa drivers=llvmpipe winsys=xlib dri=false -k
+Alternatively, you can build it with GNU make, if you prefer, by invoking it as
+
+ make linux-llvm
+
+but the rest of these instructions assume that scons is used.
+
Using
=====
Building will create a drop-in alternative for libGL.so. To use it set the
environment variables:
- export LD_LIBRARY_PATH=$PWD/build/linux-x86-debug/lib:$LD_LIBRARY_PATH
export LD_LIBRARY_PATH=$PWD/build/linux-x86_64-debug/lib:$LD_LIBRARY_PATH
+or
+
+ export LD_LIBRARY_PATH=$PWD/build/linux-x86-debug/lib:$LD_LIBRARY_PATH
+
+For performance evaluation pass debug=no to scons, and use the corresponding
+lib directory without the "-debug" suffix.
+
Unit testing
============
- lp_test_conv: SIMD vector conversion
- lp_test_format: pixel unpacking/packing
-Some of this tests can output results and benchmarks to a tab-seperated-file
+Some of this tests can output results and benchmarks to a tab-separated-file
for posterior analysis, e.g.:
- build/linux-x86_64/gallium/drivers/llvmpipe/lp_test_blend -o blend.tsv
+ build/linux-x86_64-debug/gallium/drivers/llvmpipe/lp_test_blend -o blend.tsv
Development Notes
=================
+- When looking to this code by the first time start in lp_state_fs.c, and
+ then skim through the lp_bld_* functions called in there, and the comments
+ at the top of the lp_bld_*.c functions.
+
+- All lp_bld_*.[ch] are isolated from the rest of the driver, and could/may be
+ put in a stand-alone Gallium state -> LLVM IR translation module.
+
- We use LLVM-C bindings for now. They are not documented, but follow the C++
interfaces very closely, and appear to be complete enough for code
generation. See
http://npcontemplation.blogspot.com/2008/06/secret-of-llvm-c-bindings.html
- for a standalone example.
+ for a stand-alone example.
projects / mesa.git / blobdiff