On 04/14/2016 06:52 PM, Eduardo Lima Mitev wrote: > Hi, > > This is a series adding a new NIR pass that will combine redundant SSBO, > shared variable and image load instructions. It is based on a previous series > that Iago Toral [1] sent a few months ago, which I have updated to account > for changes in NIR since then, and also added support for shared variables > and image load/store. > > Currently, the emitted load instructions for these types of variables are > highly redundant. For example, assuming 'value' is an SSBO float, doing: > > float next = value + 1.0; > float prev = value - 1.0; > > will generate two redundant load_ssbo instructions. The extreme case of this > is: > > mat4 mult = ssbo_mat4 * ssbo_mat4; > > which will spwan 16 load_ssbo instructions. > > Compute shader's shared variables and image loads (from ARB_image_load_store) > suffer from the same problem. This pass coaleses the redundant loads, and is > also able to combine a load with a previous store to the same address. > > I'm still working on a piglit test series that tied up the different corner > cases, but it doesn't hurt to get a few eyes on this already. The WIP piglit > branch is at: > https://github.com/Igalia/piglit/commits/nir-opt-load-combine-rc1 > You can see there a test example for the matrix multiplication cases: > https://github.com/Igalia/piglit/commit/b7ea6d2553891c7eec993c39352a10925ebcefbc. > This pass is able to reduce the emitted instructions from 210 to 134 (~64%), > comparing to Mesa master. >
On a gen7 (HSW GT2). And there are only 5 patches, not 6. The last one in the branch was a debug-only patch that was removed. Eduardo _______________________________________________ mesa-dev mailing list [email protected] https://lists.freedesktop.org/mailman/listinfo/mesa-dev
