From ec4822a316d63a45e3084753359b757d96c3917d Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Sat, 19 Feb 2011 01:05:11 -0800 Subject: [PATCH] i965/fs: Avoid register coalescing away gen6 MATH workarounds. The code that generates MATH instructions attempts to work around the hardware ignoring source modifiers (abs and negate) by emitting moves into temporaries. Unfortunately, this pass coalesced those registers, restoring the original problem. Avoid doing that. Fixes several OpenGL ES2 conformance failures on Sandybridge. NOTE: This is a candidate for the 7.10 branch. Reviewed-by: Eric Anholt (cherry picked from commit 2c2686b912de19a430aba9f5ea5fa679eabdc5c6) --- src/mesa/drivers/dri/i965/brw_fs.cpp | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index b7425a00593..eaa9ae6ac36 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -2980,6 +2980,8 @@ fs_visitor::register_coalesce() inst->dst.type != inst->src[0].type) continue; + bool has_source_modifiers = inst->src[0].abs || inst->src[0].negate; + /* Found a move of a GRF to a GRF. Let's see if we can coalesce * them: check for no writes to either one until the exit of the * program. @@ -3012,6 +3014,14 @@ fs_visitor::register_coalesce() break; } } + + /* The gen6 MATH instruction can't handle source modifiers, so avoid + * coalescing those for now. We should do something more specific. + */ + if (intel->gen == 6 && scan_inst->is_math() && has_source_modifiers) { + interfered = true; + break; + } } if (interfered) { continue;