1 /**************************************************************************
3 * Copyright 2009 VMware, Inc.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 **************************************************************************/
30 * Depth/stencil testing to LLVM IR translation.
32 * To be done accurately/efficiently the depth/stencil test must be done with
33 * the same type/format of the depth/stencil buffer, which implies massaging
34 * the incoming depths to fit into place. Using a more straightforward
35 * type/format for depth/stencil values internally and only convert when
36 * flushing would avoid this, but it would most likely result in depth fighting
39 * We are free to use a different pixel layout though. Since our basic
40 * processing unit is a quad (2x2 pixel block) we store the depth/stencil
41 * values tiled, a quad at time. That is, a depth buffer containing
49 * will actually be stored in memory as
51 * Z11 Z12 Z21 Z22 Z13 Z14 Z23 Z24 ...
52 * Z31 Z32 Z41 Z42 Z33 Z34 Z43 Z44 ...
53 * ... ... ... ... ... ... ... ... ...
57 * Two-sided stencil test is supported but probably not as efficient as
58 * it could be. Currently, we use if/then/else constructs to do the
59 * operations for front vs. back-facing polygons. We could probably do
60 * both the front and back arithmetic then use a Select() instruction to
61 * choose the result depending on polyon orientation. We'd have to
62 * measure performance both ways and see which is better.
64 * @author Jose Fonseca <jfonseca@vmware.com>
67 #include "pipe/p_state.h"
68 #include "util/u_format.h"
70 #include "gallivm/lp_bld_type.h"
71 #include "gallivm/lp_bld_arit.h"
72 #include "gallivm/lp_bld_bitarit.h"
73 #include "gallivm/lp_bld_const.h"
74 #include "gallivm/lp_bld_conv.h"
75 #include "gallivm/lp_bld_logic.h"
76 #include "gallivm/lp_bld_flow.h"
77 #include "gallivm/lp_bld_intr.h"
78 #include "gallivm/lp_bld_debug.h"
79 #include "gallivm/lp_bld_swizzle.h"
81 #include "lp_bld_depth.h"
84 /** Used to select fields from pipe_stencil_state */
94 * Do the stencil test comparison (compare FB stencil values against ref value).
95 * This will be used twice when generating two-sided stencil code.
96 * \param stencil the front/back stencil state
97 * \param stencilRef the stencil reference value, replicated as a vector
98 * \param stencilVals vector of stencil values from framebuffer
99 * \return vector mask of pass/fail values (~0 or 0)
102 lp_build_stencil_test_single(struct lp_build_context
*bld
,
103 const struct pipe_stencil_state
*stencil
,
104 LLVMValueRef stencilRef
,
105 LLVMValueRef stencilVals
)
107 const unsigned stencilMax
= 255; /* XXX fix */
108 struct lp_type type
= bld
->type
;
113 assert(stencil
->enabled
);
115 if (stencil
->valuemask
!= stencilMax
) {
116 /* compute stencilRef = stencilRef & valuemask */
117 LLVMValueRef valuemask
= lp_build_const_int_vec(type
, stencil
->valuemask
);
118 stencilRef
= LLVMBuildAnd(bld
->builder
, stencilRef
, valuemask
, "");
119 /* compute stencilVals = stencilVals & valuemask */
120 stencilVals
= LLVMBuildAnd(bld
->builder
, stencilVals
, valuemask
, "");
123 res
= lp_build_cmp(bld
, stencil
->func
, stencilRef
, stencilVals
);
130 * Do the one or two-sided stencil test comparison.
131 * \sa lp_build_stencil_test_single
132 * \param front_facing an integer vector mask, indicating front (~0) or back
133 * (0) facing polygon. If NULL, assume front-facing.
136 lp_build_stencil_test(struct lp_build_context
*bld
,
137 const struct pipe_stencil_state stencil
[2],
138 LLVMValueRef stencilRefs
[2],
139 LLVMValueRef stencilVals
,
140 LLVMValueRef front_facing
)
144 assert(stencil
[0].enabled
);
146 /* do front face test */
147 res
= lp_build_stencil_test_single(bld
, &stencil
[0],
148 stencilRefs
[0], stencilVals
);
150 if (stencil
[1].enabled
&& front_facing
) {
151 /* do back face test */
152 LLVMValueRef back_res
;
154 back_res
= lp_build_stencil_test_single(bld
, &stencil
[1],
155 stencilRefs
[1], stencilVals
);
157 res
= lp_build_select(bld
, front_facing
, res
, back_res
);
165 * Apply the stencil operator (add/sub/keep/etc) to the given vector
167 * \return new stencil values vector
170 lp_build_stencil_op_single(struct lp_build_context
*bld
,
171 const struct pipe_stencil_state
*stencil
,
173 LLVMValueRef stencilRef
,
174 LLVMValueRef stencilVals
)
177 struct lp_type type
= bld
->type
;
179 LLVMValueRef max
= lp_build_const_int_vec(type
, 0xff);
186 stencil_op
= stencil
->fail_op
;
189 stencil_op
= stencil
->zfail_op
;
192 stencil_op
= stencil
->zpass_op
;
195 assert(0 && "Invalid stencil_op mode");
196 stencil_op
= PIPE_STENCIL_OP_KEEP
;
199 switch (stencil_op
) {
200 case PIPE_STENCIL_OP_KEEP
:
202 /* we can return early for this case */
204 case PIPE_STENCIL_OP_ZERO
:
207 case PIPE_STENCIL_OP_REPLACE
:
210 case PIPE_STENCIL_OP_INCR
:
211 res
= lp_build_add(bld
, stencilVals
, bld
->one
);
212 res
= lp_build_min(bld
, res
, max
);
214 case PIPE_STENCIL_OP_DECR
:
215 res
= lp_build_sub(bld
, stencilVals
, bld
->one
);
216 res
= lp_build_max(bld
, res
, bld
->zero
);
218 case PIPE_STENCIL_OP_INCR_WRAP
:
219 res
= lp_build_add(bld
, stencilVals
, bld
->one
);
220 res
= LLVMBuildAnd(bld
->builder
, res
, max
, "");
222 case PIPE_STENCIL_OP_DECR_WRAP
:
223 res
= lp_build_sub(bld
, stencilVals
, bld
->one
);
224 res
= LLVMBuildAnd(bld
->builder
, res
, max
, "");
226 case PIPE_STENCIL_OP_INVERT
:
227 res
= LLVMBuildNot(bld
->builder
, stencilVals
, "");
228 res
= LLVMBuildAnd(bld
->builder
, res
, max
, "");
231 assert(0 && "bad stencil op mode");
240 * Do the one or two-sided stencil test op/update.
243 lp_build_stencil_op(struct lp_build_context
*bld
,
244 const struct pipe_stencil_state stencil
[2],
246 LLVMValueRef stencilRefs
[2],
247 LLVMValueRef stencilVals
,
249 LLVMValueRef front_facing
)
254 assert(stencil
[0].enabled
);
256 /* do front face op */
257 res
= lp_build_stencil_op_single(bld
, &stencil
[0], op
,
258 stencilRefs
[0], stencilVals
);
260 if (stencil
[1].enabled
&& front_facing
) {
261 /* do back face op */
262 LLVMValueRef back_res
;
264 back_res
= lp_build_stencil_op_single(bld
, &stencil
[1], op
,
265 stencilRefs
[1], stencilVals
);
267 res
= lp_build_select(bld
, front_facing
, res
, back_res
);
270 if (stencil
->writemask
!= 0xff) {
271 /* mask &= stencil->writemask */
272 LLVMValueRef writemask
= lp_build_const_int_vec(bld
->type
, stencil
->writemask
);
273 mask
= LLVMBuildAnd(bld
->builder
, mask
, writemask
, "");
274 /* res = (res & mask) | (stencilVals & ~mask) */
275 res
= lp_build_select_bitwise(bld
, writemask
, res
, stencilVals
);
278 /* res = mask ? res : stencilVals */
279 res
= lp_build_select(bld
, mask
, res
, stencilVals
);
288 * Return a type appropriate for depth/stencil testing.
291 lp_depth_type(const struct util_format_description
*format_desc
,
297 assert(format_desc
->colorspace
== UTIL_FORMAT_COLORSPACE_ZS
);
298 assert(format_desc
->block
.width
== 1);
299 assert(format_desc
->block
.height
== 1);
301 swizzle
= format_desc
->swizzle
[0];
304 memset(&type
, 0, sizeof type
);
305 type
.width
= format_desc
->block
.bits
;
307 if(format_desc
->channel
[swizzle
].type
== UTIL_FORMAT_TYPE_FLOAT
) {
308 type
.floating
= TRUE
;
309 assert(swizzle
== 0);
310 assert(format_desc
->channel
[swizzle
].size
== format_desc
->block
.bits
);
312 else if(format_desc
->channel
[swizzle
].type
== UTIL_FORMAT_TYPE_UNSIGNED
) {
313 assert(format_desc
->block
.bits
<= 32);
314 if(format_desc
->channel
[swizzle
].normalized
)
320 assert(type
.width
<= length
);
321 type
.length
= length
/ type
.width
;
328 * Compute bitmask and bit shift to apply to the incoming fragment Z values
329 * and the Z buffer values needed before doing the Z comparison.
331 * Note that we leave the Z bits in the position that we find them
332 * in the Z buffer (typically 0xffffff00 or 0x00ffffff). That lets us
333 * get by with fewer bit twiddling steps.
336 get_z_shift_and_mask(const struct util_format_description
*format_desc
,
337 unsigned *shift
, unsigned *mask
)
339 const unsigned total_bits
= format_desc
->block
.bits
;
342 unsigned padding_left
, padding_right
;
344 assert(format_desc
->colorspace
== UTIL_FORMAT_COLORSPACE_ZS
);
345 assert(format_desc
->block
.width
== 1);
346 assert(format_desc
->block
.height
== 1);
348 z_swizzle
= format_desc
->swizzle
[0];
350 if (z_swizzle
== UTIL_FORMAT_SWIZZLE_NONE
)
354 for (chan
= 0; chan
< z_swizzle
; ++chan
)
355 padding_right
+= format_desc
->channel
[chan
].size
;
358 total_bits
- (padding_right
+ format_desc
->channel
[z_swizzle
].size
);
360 if (padding_left
|| padding_right
) {
361 unsigned long long mask_left
= (1ULL << (total_bits
- padding_left
)) - 1;
362 unsigned long long mask_right
= (1ULL << (padding_right
)) - 1;
363 *mask
= mask_left
^ mask_right
;
369 *shift
= padding_left
;
376 * Compute bitmask and bit shift to apply to the framebuffer pixel values
377 * to put the stencil bits in the least significant position.
381 get_s_shift_and_mask(const struct util_format_description
*format_desc
,
382 unsigned *shift
, unsigned *mask
)
387 s_swizzle
= format_desc
->swizzle
[1];
389 if (s_swizzle
== UTIL_FORMAT_SWIZZLE_NONE
)
393 for (chan
= 0; chan
< s_swizzle
; chan
++)
394 *shift
+= format_desc
->channel
[chan
].size
;
396 sz
= format_desc
->channel
[s_swizzle
].size
;
397 *mask
= (1U << sz
) - 1U;
404 * Perform the occlusion test and increase the counter.
405 * Test the depth mask. Add the number of channel which has none zero mask
406 * into the occlusion counter. e.g. maskvalue is {-1, -1, -1, -1}.
407 * The counter will add 4.
409 * \param type holds element type of the mask vector.
410 * \param maskvalue is the depth test mask.
411 * \param counter is a pointer of the uint32 counter.
414 lp_build_occlusion_count(LLVMBuilderRef builder
,
416 LLVMValueRef maskvalue
,
417 LLVMValueRef counter
)
419 LLVMValueRef countmask
= lp_build_const_int_vec(type
, 1);
420 LLVMValueRef countv
= LLVMBuildAnd(builder
, maskvalue
, countmask
, "countv");
421 LLVMTypeRef i8v16
= LLVMVectorType(LLVMInt8Type(), 16);
422 LLVMValueRef counti
= LLVMBuildBitCast(builder
, countv
, i8v16
, "counti");
423 LLVMValueRef maskarray
[4] = {
424 LLVMConstInt(LLVMInt32Type(), 0, 0),
425 LLVMConstInt(LLVMInt32Type(), 4, 0),
426 LLVMConstInt(LLVMInt32Type(), 8, 0),
427 LLVMConstInt(LLVMInt32Type(), 12, 0),
429 LLVMValueRef shufflemask
= LLVMConstVector(maskarray
, 4);
430 LLVMValueRef shufflev
= LLVMBuildShuffleVector(builder
, counti
, LLVMGetUndef(i8v16
), shufflemask
, "shufflev");
431 LLVMValueRef shuffle
= LLVMBuildBitCast(builder
, shufflev
, LLVMInt32Type(), "shuffle");
432 LLVMValueRef count
= lp_build_intrinsic_unary(builder
, "llvm.ctpop.i32", LLVMInt32Type(), shuffle
);
433 LLVMValueRef orig
= LLVMBuildLoad(builder
, counter
, "orig");
434 LLVMValueRef incr
= LLVMBuildAdd(builder
, orig
, count
, "incr");
435 LLVMBuildStore(builder
, incr
, counter
);
441 * Generate code for performing depth and/or stencil tests.
442 * We operate on a vector of values (typically a 2x2 quad).
444 * \param depth the depth test state
445 * \param stencil the front/back stencil state
446 * \param type the data type of the fragment depth/stencil values
447 * \param format_desc description of the depth/stencil surface
448 * \param mask the alive/dead pixel mask for the quad (vector)
449 * \param stencil_refs the front/back stencil ref values (scalar)
450 * \param z_src the incoming depth/stencil values (a 2x2 quad, float32)
451 * \param zs_dst_ptr pointer to depth/stencil values in framebuffer
452 * \param facing contains float value indicating front/back facing polygon
455 lp_build_depth_stencil_test(LLVMBuilderRef builder
,
456 const struct pipe_depth_state
*depth
,
457 const struct pipe_stencil_state stencil
[2],
458 struct lp_type z_src_type
,
459 const struct util_format_description
*format_desc
,
460 struct lp_build_mask_context
*mask
,
461 LLVMValueRef stencil_refs
[2],
463 LLVMValueRef zs_dst_ptr
,
465 LLVMValueRef
*zs_value
,
469 struct lp_build_context bld
;
470 struct lp_build_context sbld
;
471 struct lp_type s_type
;
472 LLVMValueRef zs_dst
, z_dst
= NULL
;
473 LLVMValueRef stencil_vals
= NULL
;
474 LLVMValueRef z_bitmask
= NULL
, stencil_shift
= NULL
;
475 LLVMValueRef z_pass
= NULL
, s_pass_mask
= NULL
;
476 LLVMValueRef orig_mask
= lp_build_mask_value(mask
);
477 LLVMValueRef front_facing
= NULL
;
479 /* Prototype a simpler path:
481 if (z_src_type
.floating
&&
482 format_desc
->format
== PIPE_FORMAT_X8Z24_UNORM
&&
485 LLVMValueRef zscaled
;
486 LLVMValueRef const_ffffff_float
;
487 LLVMValueRef const_8_int
;
488 LLVMTypeRef int32_vec_type
;
490 /* We know the values in z_dst are all >= 0, so allow
491 * lp_build_compare to use signed compare intrinsics:
498 type
.length
= z_src_type
.length
;
500 int32_vec_type
= LLVMVectorType(LLVMInt32Type(), z_src_type
.length
);
502 const_8_int
= lp_build_const_int_vec(type
, 8);
503 const_ffffff_float
= lp_build_const_vec(z_src_type
, (float)0xffffff);
505 zscaled
= LLVMBuildFMul(builder
, z_src
, const_ffffff_float
, "zscaled");
506 z_src
= LLVMBuildFPToSI(builder
, zscaled
, int32_vec_type
, "z_src");
508 /* Load current z/stencil value from z/stencil buffer */
509 z_dst
= LLVMBuildLoad(builder
, zs_dst_ptr
, "zsbufval");
510 z_dst
= LLVMBuildLShr(builder
, z_dst
, const_8_int
, "z_dst");
512 /* compare src Z to dst Z, returning 'pass' mask */
513 z_pass
= lp_build_compare(builder
,
515 depth
->func
, z_src
, z_dst
);
517 lp_build_mask_update(mask
, z_pass
);
520 lp_build_mask_check(mask
);
522 /* No need to worry about old stencil contents, just blend the
523 * old and new values and shift into the correct position for
526 if (depth
->writemask
) {
528 lp_build_context_init(&bld
, builder
, type
);
530 z_dst
= lp_build_select(&bld
, lp_build_mask_value(mask
), z_src
, z_dst
);
531 z_dst
= LLVMBuildShl(builder
, z_dst
, const_8_int
, "z_dst");
539 * Depths are expected to be between 0 and 1, even if they are stored in
540 * floats. Setting these bits here will ensure that the lp_build_conv() call
541 * below won't try to unnecessarily clamp the incoming values.
543 if(z_src_type
.floating
) {
544 z_src_type
.sign
= FALSE
;
545 z_src_type
.norm
= TRUE
;
548 assert(!z_src_type
.sign
);
549 assert(z_src_type
.norm
);
552 /* Pick the depth type. */
553 type
= lp_depth_type(format_desc
, z_src_type
.width
*z_src_type
.length
);
555 /* FIXME: Cope with a depth test type with a different bit width. */
556 assert(type
.width
== z_src_type
.width
);
557 assert(type
.length
== z_src_type
.length
);
559 /* Convert fragment Z from float to integer */
560 lp_build_conv(builder
, z_src_type
, type
, &z_src
, 1, &z_src
, 1);
562 zs_dst_ptr
= LLVMBuildBitCast(builder
,
564 LLVMPointerType(lp_build_vec_type(type
), 0), "");
568 /* Sanity checking */
570 const unsigned z_swizzle
= format_desc
->swizzle
[0];
571 const unsigned s_swizzle
= format_desc
->swizzle
[1];
573 assert(z_swizzle
!= UTIL_FORMAT_SWIZZLE_NONE
||
574 s_swizzle
!= UTIL_FORMAT_SWIZZLE_NONE
);
576 assert(depth
->enabled
|| stencil
[0].enabled
);
578 assert(format_desc
->colorspace
== UTIL_FORMAT_COLORSPACE_ZS
);
579 assert(format_desc
->block
.width
== 1);
580 assert(format_desc
->block
.height
== 1);
582 if (stencil
[0].enabled
) {
583 assert(format_desc
->format
== PIPE_FORMAT_Z24_UNORM_S8_USCALED
||
584 format_desc
->format
== PIPE_FORMAT_S8_USCALED_Z24_UNORM
);
587 assert(z_swizzle
< 4);
588 assert(format_desc
->block
.bits
== type
.width
);
590 assert(z_swizzle
== 0);
591 assert(format_desc
->channel
[z_swizzle
].type
==
592 UTIL_FORMAT_TYPE_FLOAT
);
593 assert(format_desc
->channel
[z_swizzle
].size
==
594 format_desc
->block
.bits
);
597 assert(format_desc
->channel
[z_swizzle
].type
==
598 UTIL_FORMAT_TYPE_UNSIGNED
);
599 assert(format_desc
->channel
[z_swizzle
].normalized
);
607 /* Setup build context for Z vals */
608 lp_build_context_init(&bld
, builder
, type
);
610 /* Setup build context for stencil vals */
611 s_type
= lp_type_int_vec(type
.width
);
612 lp_build_context_init(&sbld
, builder
, s_type
);
614 /* Load current z/stencil value from z/stencil buffer */
615 zs_dst
= LLVMBuildLoad(builder
, zs_dst_ptr
, "");
617 lp_build_name(zs_dst
, "zsbufval");
620 /* Compute and apply the Z/stencil bitmasks and shifts.
623 unsigned z_shift
, z_mask
;
624 unsigned s_shift
, s_mask
;
626 if (get_z_shift_and_mask(format_desc
, &z_shift
, &z_mask
)) {
628 LLVMValueRef shift
= lp_build_const_int_vec(type
, z_shift
);
629 z_src
= LLVMBuildLShr(builder
, z_src
, shift
, "");
632 if (z_mask
!= 0xffffffff) {
633 LLVMValueRef mask
= lp_build_const_int_vec(type
, z_mask
);
634 z_src
= LLVMBuildAnd(builder
, z_src
, mask
, "");
635 z_dst
= LLVMBuildAnd(builder
, zs_dst
, mask
, "");
636 z_bitmask
= mask
; /* used below */
642 lp_build_name(z_dst
, "zsbuf.z");
645 if (get_s_shift_and_mask(format_desc
, &s_shift
, &s_mask
)) {
647 LLVMValueRef shift
= lp_build_const_int_vec(type
, s_shift
);
648 stencil_vals
= LLVMBuildLShr(builder
, zs_dst
, shift
, "");
649 stencil_shift
= shift
; /* used below */
652 stencil_vals
= zs_dst
;
655 if (s_mask
!= 0xffffffff) {
656 LLVMValueRef mask
= lp_build_const_int_vec(type
, s_mask
);
657 stencil_vals
= LLVMBuildAnd(builder
, stencil_vals
, mask
, "");
660 lp_build_name(stencil_vals
, "stencil");
664 if (stencil
[0].enabled
) {
667 LLVMValueRef zero
= LLVMConstReal(LLVMFloatType(), 0.0);
669 /* front_facing = face > 0.0 ? ~0 : 0 */
670 front_facing
= LLVMBuildFCmp(builder
, LLVMRealUGT
, face
, zero
, "");
671 front_facing
= LLVMBuildSExt(builder
, front_facing
,
672 LLVMIntType(bld
.type
.length
*bld
.type
.width
),
674 front_facing
= LLVMBuildBitCast(builder
, front_facing
,
675 bld
.int_vec_type
, "");
678 /* convert scalar stencil refs into vectors */
679 stencil_refs
[0] = lp_build_broadcast_scalar(&bld
, stencil_refs
[0]);
680 stencil_refs
[1] = lp_build_broadcast_scalar(&bld
, stencil_refs
[1]);
682 s_pass_mask
= lp_build_stencil_test(&sbld
, stencil
,
683 stencil_refs
, stencil_vals
,
686 /* apply stencil-fail operator */
688 LLVMValueRef s_fail_mask
= lp_build_andnot(&bld
, orig_mask
, s_pass_mask
);
689 stencil_vals
= lp_build_stencil_op(&sbld
, stencil
, S_FAIL_OP
,
690 stencil_refs
, stencil_vals
,
691 s_fail_mask
, front_facing
);
695 if (depth
->enabled
) {
696 /* compare src Z to dst Z, returning 'pass' mask */
697 z_pass
= lp_build_cmp(&bld
, depth
->func
, z_src
, z_dst
);
699 if (!stencil
[0].enabled
) {
700 /* We can potentially skip all remaining operations here, but only
701 * if stencil is disabled because we still need to update the stencil
702 * buffer values. Don't need to update Z buffer values.
704 lp_build_mask_update(mask
, z_pass
);
707 lp_build_mask_check(mask
);
712 if (depth
->writemask
) {
713 LLVMValueRef zselectmask
= lp_build_mask_value(mask
);
715 /* mask off bits that failed Z test */
716 zselectmask
= LLVMBuildAnd(builder
, zselectmask
, z_pass
, "");
718 /* mask off bits that failed stencil test */
720 zselectmask
= LLVMBuildAnd(builder
, zselectmask
, s_pass_mask
, "");
723 /* if combined Z/stencil format, mask off the stencil bits */
725 zselectmask
= LLVMBuildAnd(builder
, zselectmask
, z_bitmask
, "");
728 /* Mix the old and new Z buffer values.
729 * z_dst[i] = (zselectmask[i] & z_src[i]) | (~zselectmask[i] & z_dst[i])
731 z_dst
= lp_build_select_bitwise(&bld
, zselectmask
, z_src
, z_dst
);
734 if (stencil
[0].enabled
) {
735 /* update stencil buffer values according to z pass/fail result */
736 LLVMValueRef z_fail_mask
, z_pass_mask
;
738 /* apply Z-fail operator */
739 z_fail_mask
= lp_build_andnot(&bld
, orig_mask
, z_pass
);
740 stencil_vals
= lp_build_stencil_op(&sbld
, stencil
, Z_FAIL_OP
,
741 stencil_refs
, stencil_vals
,
742 z_fail_mask
, front_facing
);
744 /* apply Z-pass operator */
745 z_pass_mask
= LLVMBuildAnd(bld
.builder
, orig_mask
, z_pass
, "");
746 stencil_vals
= lp_build_stencil_op(&sbld
, stencil
, Z_PASS_OP
,
747 stencil_refs
, stencil_vals
,
748 z_pass_mask
, front_facing
);
752 /* No depth test: apply Z-pass operator to stencil buffer values which
753 * passed the stencil test.
755 s_pass_mask
= LLVMBuildAnd(bld
.builder
, orig_mask
, s_pass_mask
, "");
756 stencil_vals
= lp_build_stencil_op(&sbld
, stencil
, Z_PASS_OP
,
757 stencil_refs
, stencil_vals
,
758 s_pass_mask
, front_facing
);
761 /* The Z bits are already in the right place but we may need to shift the
762 * stencil bits before ORing Z with Stencil to make the final pixel value.
764 if (stencil_vals
&& stencil_shift
)
765 stencil_vals
= LLVMBuildShl(bld
.builder
, stencil_vals
,
768 /* Finally, merge/store the z/stencil values */
769 if ((depth
->enabled
&& depth
->writemask
) ||
770 (stencil
[0].enabled
&& stencil
[0].writemask
)) {
772 if (z_dst
&& stencil_vals
)
773 zs_dst
= LLVMBuildOr(bld
.builder
, z_dst
, stencil_vals
, "");
777 zs_dst
= stencil_vals
;
783 lp_build_mask_update(mask
, s_pass_mask
);
785 if (depth
->enabled
&& stencil
[0].enabled
)
786 lp_build_mask_update(mask
, z_pass
);
789 lp_build_mask_check(mask
);
796 lp_build_deferred_depth_write(LLVMBuilderRef builder
,
797 struct lp_type z_src_type
,
798 const struct util_format_description
*format_desc
,
799 struct lp_build_mask_context
*mask
,
800 LLVMValueRef zs_dst_ptr
,
801 LLVMValueRef zs_value
)
804 struct lp_build_context bld
;
807 /* XXX: pointlessly redo type logic:
809 type
= lp_depth_type(format_desc
, z_src_type
.width
*z_src_type
.length
);
810 lp_build_context_init(&bld
, builder
, type
);
812 z_dst
= LLVMBuildLoad(builder
, zs_dst_ptr
, "zsbufval");
813 z_dst
= lp_build_select(&bld
, lp_build_mask_value(mask
), zs_value
, z_dst
);
815 LLVMBuildStore(builder
, z_dst
, zs_dst_ptr
);