From 217af32c2d6afab5e1907cc16fb4b6feb982abe7 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Mon, 3 Aug 2009 17:12:43 -0700 Subject: [PATCH] i965: Even if no VS inputs are set, still load some amount of URB as required. See comment on Vertex URB Entry Read Length for VS_STATE. This, combined with the previous three commits, fixes #22945. (cherry picked from commit e340d4f9866db4bae391288e83a630a310b0dd2b) --- src/mesa/drivers/dri/i965/brw_vs_emit.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/src/mesa/drivers/dri/i965/brw_vs_emit.c b/src/mesa/drivers/dri/i965/brw_vs_emit.c index 6792c3a..b95079a 100644 --- a/src/mesa/drivers/dri/i965/brw_vs_emit.c +++ b/src/mesa/drivers/dri/i965/brw_vs_emit.c @@ -124,6 +124,11 @@ static void brw_vs_alloc_regs( struct brw_vs_compile *c ) reg++; } } + /* If there are no inputs, we'll still be reading one attribute's worth + * because it's required -- see urb_read_length setting. + */ + if (c->nr_inputs == 0) + reg++; /* Allocate outputs: TODO: could organize the non-position outputs * to go straight into message regs. @@ -201,6 +206,12 @@ static void brw_vs_alloc_regs( struct brw_vs_compile *c ) * vertex urb, so is half the amount: */ c->prog_data.urb_read_length = (c->nr_inputs + 1) / 2; + /* Setting this field to 0 leads to undefined behavior according to the + * the VS_STATE docs. Our VUEs will always have at least one attribute + * sitting in them, even if it's padding. + */ + if (c->prog_data.urb_read_length == 0) + c->prog_data.urb_read_length = 1; /* The VS VUEs are shared by VF (outputting our inputs) and VS, so size * them to fit the biggest thing they need to. -- 2.7.4