On Sat, Jan 30, 2021 at 9:45 AM Chris Wilson chris@chris-wilson.co.uk wrote:
Quoting Vinicius Tinti (2021-01-30 12:34:11)
On Fri, Jan 29, 2021 at 08:55:54PM +0000, Chris Wilson wrote:
Quoting Vinicius Tinti (2021-01-29 18:15:19)
By enabling -Wunreachable-code-aggressive on Clang the following code paths are unreachable.
That code exists as commentary and, especially for sdvo, library functions that we may need in future.
I would argue that this code could be removed since it is in git history. It can be restored when needed.
This will make the code cleaner.
It doesn't change the control flow, so no complexity argument. It removes documentation from the code, so I have the opposite opinion.
The last change in sdvo related to this function is from commit ce22c320b8ca ("drm/i915/sdvo: convert to encoder disable/enable"), which dates from 2012.
It has not been used or changed for a long time. I think it could be converted to a block comment. This will preserve the documentation purpose. What do you think?
All this will avoid having "if (0)".
The ivb-gt1 case => as we now set the gt level for ivb, should we not enable the optimisation for ivb unaffected by the w/a? Just no one has taken the time to see if it causes a regression.
I don't know. I just found out that the code is unreachable.
For error state, the question remains whether we should revert to uncompressed data if the compressed stream is larger than the original.
I don't know too.
In this last two cases the code could be commented and the decisions and problems explained in the comment section.
They already are, that is the point.
I meant making them a block comment. For example:
/* * Enabling HiZ Raw Stall Optimization, at this point, causes corruption. * * Calling wa_masked_dis with the arguments wal, CACHE_MODE_0_GEN7, * HIZ_RAW_STALL_OPT_DISABLE will cause an HiZ corruption on ivb:g1. */
/* * Should fallback to uncompressed if we increase size * (zstream->total_out > zstream->total_in) by returning -E2BIG? */
-Chris