With an awful O(n^2) algorithm that searches previous instructions for dead writes.
total instructions in shared programs: 805582 -> 788074 (-2.17%) instructions in affected programs: 144561 -> 127053 (-12.11%)
9cd51bb i965/vec4: Eliminate writes that are never read.
src/mesa/drivers/dri/i965/brw_vec4.cpp | 46 ++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
Upstream: cgit.freedesktop.org