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Connor Abbott 94cb129d51 ir3/ra: Fix off-by-one issues with live-range extension
The intersects() function assumes that inside each instruction values
always die before they are defined, so that if the end of one range is
the same instruction as the beginning of the next then they don't
intersect. However, this isn't the case for values that become live at
the beginning of a basic block, which become live *before* the first
instruction, or instructions that die at the end of a basic block which
die after the last instruction.

For example, imagine that we have two values, A which is defined earlier
in the block and B which is defined in the last instruction of the block
and both die at the end of the basic block (e.g. are used in the next
iteration of a loop). We would compute a range for A of, say, (10, 20)
and for B of (20, 20) since each block's end_ip is the same as the ip of
the last instruction, and RA would consider them to not interfere.
There's a similar problem with values that become live at the beginning.

The fix is to offset the block's start_ip and end_ip by one so that they
don't correspond to any actual instruction. One way to think about this
is that we're adding fake instructions at the beginning and end of a
block where values become live & die. We could invert the order, so that
values consumed by each instruction are considered dead at the end of
the previous instruction, but then values that become dead at the
beginning of the basic block would incorrectly have an empty live range,
with a similar problem at the end of the basic block if we try to say
that values are defined at the beginning of the next instruction. So
the extra padding instructions are unavoidable.

This fixes an accidental infinite loop in the shader for
dEQP-VK.spirv_assembly.type.scalar.u32.switch_vert.

Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4614>
2020-04-18 17:31:56 +00:00
.appveyor Appveyor: Quickly fix meson build. 2019-11-14 21:45:23 +00:00
.gitlab/issue_templates gitlab: add bug report template 2020-03-23 17:15:42 +00:00
.gitlab-ci draw: fix user culling pipeline order. (v2) 2020-04-15 14:26:29 +10:00
bin gen_release_notes: resolve ambiguity by renaming version to previous_version and next_version to this_version 2020-03-12 12:57:11 +00:00
build-support configure: commit test files 2017-10-16 16:32:43 -07:00
docs docs: update for recently-added nvc0 features 2020-04-16 15:58:37 -04:00
doxygen doxygen: Plumb through gallium/ to automated documentation 2016-05-30 17:53:45 +01:00
include intel: Add TGL PCI ID 2020-03-21 23:49:38 -07:00
scons scons/windows: Support build with LLVM 10. 2020-04-14 08:40:56 +00:00
src ir3/ra: Fix off-by-one issues with live-range extension 2020-04-18 17:31:56 +00:00
subprojects meson: use github URL for wraps instead of completely unreliable wrapdb 2020-01-16 23:06:43 +00:00
.dir-locals.el dir-locals.el: Adds White Space support 2016-11-14 19:17:49 +02:00
.editorconfig docs: fixup indentation 2020-01-18 11:39:32 +01:00
.gitignore intel/tools: Add unit tests for assembler 2019-05-07 14:33:48 -07:00
.gitlab-ci.yml Revert "CI: Disable Windows/VS2019 builds" 2020-04-16 22:40:24 +00:00
.mailmap .mailmap: add an alias for Zhongmin Wu 2020-04-16 11:46:15 +00:00
.travis.yml travis: autodetect python version instead of hard-coding it 2019-12-21 20:23:08 +00:00
Android.common.mk android: mesa: Revert "android: mesa: revert "Enable asm unconditionally"" 2019-11-12 18:09:43 +00:00
Android.mk freedreno: android: fix build failure on android due to python version 2020-02-07 16:34:49 +00:00
appveyor.yml appveyor: Remove Meson job. 2020-04-01 01:13:21 +00:00
CleanSpec.mk CleanSpec.mk: Remove HOST_OUT_release 2018-08-02 15:42:40 -06:00
common.py scons: Print a deprecation warning about using scons on not windows 2019-10-24 18:33:50 +00:00
meson.build meson: tell flex that we support c99 2020-04-16 14:48:40 +00:00
meson_options.txt meson: Make shared-llvm into a tri-state boolean 2020-04-16 12:18:36 +00:00
README.rst docs: remove mailing list as way of submitting patches 2019-12-12 09:09:50 +11:00
REVIEWERS REVIEWERS: add VMware reviewers 2019-10-18 16:42:40 +00:00
SConstruct scons: Fix force_scons parsing. 2019-10-26 08:23:48 +01:00
VERSION VERSION: bump after 20.0 branch point 2020-02-02 06:54:14 +00:00

`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library
======================================================


Source
------

This repository lives at https://gitlab.freedesktop.org/mesa/mesa.
Other repositories are likely forks, and code found there is not supported.


Build & install
---------------

You can find more information in our documentation (`docs/install.html
<https://mesa3d.org/install.html>`_), but the recommended way is to use
Meson (`docs/meson.html <https://mesa3d.org/meson.html>`_):

.. code-block:: sh

  $ mkdir build
  $ cd build
  $ meson ..
  $ sudo ninja install


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-----------

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------------

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Note that Mesa uses gitlab for patches submission, review and discussions.