freedreno/a3xx/compiler: new compiler

Graphics / Mesa 3D Graphics Library / Mesa - Rob Clark [freedesktop.org] - 3 February 2014 17:26 EST

The new compiler generates a dependency graph of instructions, including a few meta-instructions to handle PHI and preserve some extra information needed for register assignment, etc.

The depth pass assigned a weight/depth to each node (based on sum of instruction cycles of a given node and all it's dependent nodes), which is used to schedule instructions. The scheduling takes into account the minimum number of cycles/slots between dependent instructions, etc. Which was something that could not be handled properly with the original compiler (which was more of a naive TGSI translator than an actual compiler).

The register assignment is currently split out as a standalone pass. I expect that it will be replaced at some point, once I figure out what to do about relative addressing (which is currently the only thing that should cause fallback to old compiler).

There are a couple new debug options for FD_MESA_DEBUG env var:

optmsgs - enable debug prints in optimizer optdump - dump instruction graph in .dot format, for example:

http://people.freedesktop.org/~robclark/a3xx/frag-0000.dot.png http://people.freedesktop.org/~robclark/a3xx/frag-0000.dot

At this point, thanks to proper handling of instruction scheduling, the new compiler fixes a lot of things that were broken before, and does not appear to break anything that was working before[1]. So even though it is not finished, it seems useful to merge it in it's current state.

[1] Not merged in this commit, because I'm not sure if it really belongs in mesa tree, but the following commit implements a simple shader emulator, which I've used to compare the output of the new compiler to the original compiler (ie. run it on all the TGSI shaders dumped out via ST_DEBUG=tgsi with various games/apps):

https://github.com/freedreno/mesa/commit/163b6306b1660e05ece2f00d264a8393d99b6f12

554f1ac freedreno/a3xx/compiler: new compiler
src/gallium/drivers/freedreno/Makefile.sources | 6 +
src/gallium/drivers/freedreno/a3xx/disasm-a3xx.c | 8 +
src/gallium/drivers/freedreno/a3xx/fd3_compiler.c | 912 ++++++++++++++++----
.../drivers/freedreno/a3xx/fd3_compiler_old.c | 17 -
src/gallium/drivers/freedreno/a3xx/fd3_program.c | 4 +-
src/gallium/drivers/freedreno/a3xx/instr-a3xx.h | 33 +
src/gallium/drivers/freedreno/a3xx/ir3.c | 2 +-
src/gallium/drivers/freedreno/a3xx/ir3.h | 110 ++-
src/gallium/drivers/freedreno/a3xx/ir3_cp.c | 155 ++++
src/gallium/drivers/freedreno/a3xx/ir3_depth.c | 156 ++++
src/gallium/drivers/freedreno/a3xx/ir3_dump.c | 416 +++++++++
src/gallium/drivers/freedreno/a3xx/ir3_flatten.c | 140 +++
src/gallium/drivers/freedreno/a3xx/ir3_ra.c | 580 +++++++++++++
src/gallium/drivers/freedreno/a3xx/ir3_sched.c | 289 +++++++
src/gallium/drivers/freedreno/a3xx/ir3_visitor.h | 154 ++++
src/gallium/drivers/freedreno/freedreno_screen.c | 2 +
src/gallium/drivers/freedreno/freedreno_util.h | 2 +
17 files changed, 2777 insertions(+), 209 deletions(-)

Upstream: cgit.freedesktop.org


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