From: Kenneth Graunke Date: Mon, 1 Sep 2014 08:36:43 +0000 (-0700) Subject: i965: Restore a lost comment about TXF offset bugs. X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a2c3cfbb4d9547f2faa44df4ca996095ce852b9e;p=mesa.git i965: Restore a lost comment about TXF offset bugs. Eric's original code to work around TXF offset bugs contained a comment explaining the problem, which was lost when Chris generalized it to an IR transformation (in commit 598ca510b8a118c3c7e18b5d031a2b116120e0a6). This commit adds the original comment to the newer code. Signed-off-by: Kenneth Graunke Reviewed-by: Chris Forbes --- diff --git a/src/mesa/drivers/dri/i965/brw_lower_unnormalized_offset.cpp b/src/mesa/drivers/dri/i965/brw_lower_unnormalized_offset.cpp index c95d7f3cac7..8c59b9e415b 100644 --- a/src/mesa/drivers/dri/i965/brw_lower_unnormalized_offset.cpp +++ b/src/mesa/drivers/dri/i965/brw_lower_unnormalized_offset.cpp @@ -66,6 +66,11 @@ brw_lower_unnormalized_offset_visitor::visit_leave(ir_texture *ir) void *mem_ctx = ralloc_parent(ir); if (ir->op == ir_txf) { + /* It appears that the ld instruction used for txf does its + * address bounds check before adding in the offset. To work + * around this, just add the integer offset to the integer texel + * coordinate, and don't put the offset in the header. + */ ir_variable *var = new(mem_ctx) ir_variable(ir->coordinate->type, "coordinate", ir_var_temporary);