[PATCH 2/9] intel gen4-5: simplify the bfc copy in the sf.

Olivier Galibert
2012-07-19T20:00:17Z

This patch is mostly designed to make followup patches simpler, but
it's a simplification by itself.

Signed-off-by: Olivier Galibert <galibert@pobox.com>
---
src/mesa/drivers/dri/i965/brw_sf_emit.c | 93 +++++++++++++++++--------------
1 file changed, 52 insertions(+), 41 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/brw_sf_emit.c b/src/mesa/drivers/dri/i965/brw_sf_emit.c
index ff6383b..9d8aa38 100644
--- a/src/mesa/drivers/dri/i965/brw_sf_emit.c
+++ b/src/mesa/drivers/dri/i965/brw_sf_emit.c
@@ -79,24 +79,9 @@ have_attr(struct brw_sf_compile *c, GLuint attr)
/***********************************************************************
* Twoside lighting
*/
-static void copy_bfc( struct brw_sf_compile *c,
- struct brw_reg vert )
-{
- struct brw_compile *p = &c->func;
- GLuint i;
-
- for (i = 0; i < 2; i++) {
- if (have_attr(c, VERT_RESULT_COL0+i) &&
- have_attr(c, VERT_RESULT_BFC0+i))
- brw_MOV(p,
- get_vert_result(c, vert, VERT_RESULT_COL0+i),
- get_vert_result(c, vert, VERT_RESULT_BFC0+i));
- }
-}
-
-
static void do_twoside_color( struct brw_sf_compile *c )
{
+ GLuint i, need_0, need_1;
struct brw_compile *p = &c->func;
GLuint backface_conditional = c->key.frontface_ccw ? BRW_CONDITIONAL_G : BRW_CONDITIONAL_L;

@@ -105,12 +90,14 @@ static void do_twoside_color( struct brw_sf_compile *c )
if (c->key.primitive == SF_UNFILLED_TRIS)
return;

- /* XXX: What happens if BFC isn't present? This could only happen
- * for user-supplied vertex programs, as t_vp_build.c always does
- * the right thing.
+ /* If the vertex shader provides both front and backface color, do
+ * the selection. Otherwise the generated code will pick up
+ * whichever there is.
*/
- if (!(have_attr(c, VERT_RESULT_COL0) && have_attr(c, VERT_RESULT_BFC0)) &&
- !(have_attr(c, VERT_RESULT_COL1) && have_attr(c, VERT_RESULT_BFC1)))
+ need_0 = have_attr(c, VERT_RESULT_COL0) && have_attr(c, VERT_RESULT_BFC0);
+ need_1 = have_attr(c, VERT_RESULT_COL1) && have_attr(c, VERT_RESULT_BFC1);
+
+ if (!need_0 && !need_1)
return;

/* Need to use BRW_EXECUTE_4 and also do an 4-wide compare in order
@@ -121,12 +108,15 @@ static void do_twoside_color( struct brw_sf_compile *c )
brw_push_insn_state(p);
brw_CMP(p, vec4(brw_null_reg()), backface_conditional, c->det, brw_imm_f(0));
brw_IF(p, BRW_EXECUTE_4);
- {
- switch (c->nr_verts) {
- case 3: copy_bfc(c, c->vert[2]);
- case 2: copy_bfc(c, c->vert[1]);
- case 1: copy_bfc(c, c->vert[0]);
- }
+ for (i=0; i<c->nr_verts; i++) {
+ if (need_0)
+ brw_MOV(p,
+ get_vert_result(c, c->vert[i], VERT_RESULT_COL0),
+ get_vert_result(c, c->vert[i], VERT_RESULT_BFC0));
+ if (need_1)
+ brw_MOV(p,
+ get_vert_result(c, c->vert[i], VERT_RESULT_COL1),
+ get_vert_result(c, c->vert[i], VERT_RESULT_BFC1));
}
brw_ENDIF(p);
brw_pop_insn_state(p);
@@ -139,20 +129,27 @@ static void do_twoside_color( struct brw_sf_compile *c )
*/

#define VERT_RESULT_COLOR_BITS (BITFIELD64_BIT(VERT_RESULT_COL0) | \
- BITFIELD64_BIT(VERT_RESULT_COL1))
+ BITFIELD64_BIT(VERT_RESULT_COL1))

static void copy_colors( struct brw_sf_compile *c,
struct brw_reg dst,
- struct brw_reg src)
+ struct brw_reg src,
+ int allow_twoside)
{
struct brw_compile *p = &c->func;
GLuint i;

for (i = VERT_RESULT_COL0; i <= VERT_RESULT_COL1; i++) {
- if (have_attr(c,i))
+ if (have_attr(c,i)) {
brw_MOV(p,
get_vert_result(c, dst, i),
get_vert_result(c, src, i));
+
+ } else if(allow_twoside && have_attr(c, i - VERT_RESULT_COL0 + VERT_RESULT_BFC0)) {
+ brw_MOV(p,
+ get_vert_result(c, dst, i - VERT_RESULT_COL0 + VERT_RESULT_BFC0),
+ get_vert_result(c, src, i - VERT_RESULT_COL0 + VERT_RESULT_BFC0));
+ }
}
}

@@ -167,9 +164,19 @@ static void do_flatshade_triangle( struct brw_sf_compile *c )
struct brw_compile *p = &c->func;
struct intel_context *intel = &p->brw->intel;
struct brw_reg ip = brw_ip_reg();
- GLuint nr = _mesa_bitcount_64(c->key.attrs & VERT_RESULT_COLOR_BITS);
GLuint jmpi = 1;

+ GLuint nr;
+
+ if (c->key.do_twoside_color) {
+ nr = ((c->key.attrs & (BITFIELD64_BIT(VERT_RESULT_COL0) | BITFIELD64_BIT(VERT_RESULT_BFC0))) != 0) +
+ ((c->key.attrs & (BITFIELD64_BIT(VERT_RESULT_COL1) | BITFIELD64_BIT(VERT_RESULT_BFC1))) != 0);
+
+ } else {
+ nr = ((c->key.attrs & BITFIELD64_BIT(VERT_RESULT_COL0)) != 0) +
+ ((c->key.attrs & BITFIELD64_BIT(VERT_RESULT_COL1)) != 0);
+ }
+
if (!nr)
return;

@@ -186,16 +193,16 @@ static void do_flatshade_triangle( struct brw_sf_compile *c )
brw_MUL(p, c->pv, c->pv, brw_imm_d(jmpi*(nr*2+1)));
brw_JMPI(p, ip, ip, c->pv);

- copy_colors(c, c->vert[1], c->vert[0]);
- copy_colors(c, c->vert[2], c->vert[0]);
+ copy_colors(c, c->vert[1], c->vert[0], c->key.do_twoside_color);
+ copy_colors(c, c->vert[2], c->vert[0], c->key.do_twoside_color);
brw_JMPI(p, ip, ip, brw_imm_d(jmpi*(nr*4+1)));

- copy_colors(c, c->vert[0], c->vert[1]);
- copy_colors(c, c->vert[2], c->vert[1]);
+ copy_colors(c, c->vert[0], c->vert[1], c->key.do_twoside_color);
+ copy_colors(c, c->vert[2], c->vert[1], c->key.do_twoside_color);
brw_JMPI(p, ip, ip, brw_imm_d(jmpi*nr*2));

- copy_colors(c, c->vert[0], c->vert[2]);
- copy_colors(c, c->vert[1], c->vert[2]);
+ copy_colors(c, c->vert[0], c->vert[2], c->key.do_twoside_color);
+ copy_colors(c, c->vert[1], c->vert[2], c->key.do_twoside_color);

brw_pop_insn_state(p);
}
@@ -224,10 +231,10 @@ static void do_flatshade_line( struct brw_sf_compile *c )

brw_MUL(p, c->pv, c->pv, brw_imm_d(jmpi*(nr+1)));
brw_JMPI(p, ip, ip, c->pv);
- copy_colors(c, c->vert[1], c->vert[0]);
+ copy_colors(c, c->vert[1], c->vert[0], 0);

brw_JMPI(p, ip, ip, brw_imm_ud(jmpi*nr));
- copy_colors(c, c->vert[0], c->vert[1]);
+ copy_colors(c, c->vert[0], c->vert[1], 0);

brw_pop_insn_state(p);
}
@@ -337,13 +344,17 @@ calculate_masks(struct brw_sf_compile *c,
if (c->key.do_flat_shading)
persp_mask = c->key.attrs & ~(BITFIELD64_BIT(VERT_RESULT_HPOS) |
BITFIELD64_BIT(VERT_RESULT_COL0) |
- BITFIELD64_BIT(VERT_RESULT_COL1));
+ BITFIELD64_BIT(VERT_RESULT_COL1) |
+ BITFIELD64_BIT(VERT_RESULT_BFC0) |
+ BITFIELD64_BIT(VERT_RESULT_BFC1));
else
persp_mask = c->key.attrs & ~(BITFIELD64_BIT(VERT_RESULT_HPOS));

if (c->key.do_flat_shading)
linear_mask = c->key.attrs & ~(BITFIELD64_BIT(VERT_RESULT_COL0) |
- BITFIELD64_BIT(VERT_RESULT_COL1));
+ BITFIELD64_BIT(VERT_RESULT_COL1) |
+ BITFIELD64_BIT(VERT_RESULT_BFC0) |
+ BITFIELD64_BIT(VERT_RESULT_BFC1));
else
linear_mask = c->key.attrs;

--
1.7.10.280.gaa39