From 34ed61b33459c975074df0e83a2161fb76526621 Mon Sep 17 00:00:00 2001 From: Iago Toral Quiroga Date: Fri, 15 Jan 2016 14:59:13 +0100 Subject: [PATCH] i965/fs/lower_simd_width: Fix registers written for split instructions When the original instruction had a stride > 1, the combined registers written by the split instructions won't amount to the same register space written by the original instruction because the split instructions will use a stride of 1. The current code assumed otherwise and computed the number of registers written by split instructions as an equal share based on the relation between the lowered width and the original execution size of the instruction. It is only after the split, when we interleave the components of the result from the lowered instructions back into the original dst register, that the original stride takes effect and we write all the registers specified by the original instruction. Just make the number of register written the same as the vgrf space we allocate for the dst of the split instruction. Fixes crashes in fp64 tests produced as a result of assigning incorrectly the number of registers written by split instructions, which led to incorrect validation of the size of the writes against the allocated vgrf space. Reviewed-by: Francisco Jerez Reviewed-by: Kenneth Graunke --- src/mesa/drivers/dri/i965/brw_fs.cpp | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index 3d331d191b7..dcbb4bd8b84 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -4722,8 +4722,8 @@ fs_visitor::lower_simd_width() split_inst.dst = dsts[i] = lbld.vgrf(inst->dst.type, dst_size); split_inst.regs_written = - DIV_ROUND_UP(inst->regs_written * lower_width, - inst->exec_size); + DIV_ROUND_UP(type_sz(inst->dst.type) * dst_size * lower_width, + REG_SIZE); } lbld.emit(split_inst); -- 2.30.2