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diff --git a/src/gallium/auxiliary/gallivm/lp_bld_depth.c b/src/gallium/auxiliary/gallivm/lp_bld_depth.c
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+/**************************************************************************
+ *
+ * Copyright 2009 VMware, Inc.
+ * All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sub license, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the
+ * next paragraph) shall be included in all copies or substantial portions
+ * of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
+ * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
+ * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+ * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ *
+ **************************************************************************/
+
+/**
+ * @file
+ * Depth/stencil testing to LLVM IR translation.
+ *
+ * To be done accurately/efficiently the depth/stencil test must be done with
+ * the same type/format of the depth/stencil buffer, which implies massaging
+ * the incoming depths to fit into place. Using a more straightforward
+ * type/format for depth/stencil values internally and only convert when
+ * flushing would avoid this, but it would most likely result in depth fighting
+ * artifacts.
+ *
+ * We are free to use a different pixel layout though. Since our basic
+ * processing unit is a quad (2x2 pixel block) we store the depth/stencil
+ * values tiled, a quad at time. That is, a depth buffer containing
+ *
+ * Z11 Z12 Z13 Z14 ...
+ * Z21 Z22 Z23 Z24 ...
+ * Z31 Z32 Z33 Z34 ...
+ * Z41 Z42 Z43 Z44 ...
+ * ... ... ... ... ...
+ *
+ * will actually be stored in memory as
+ *
+ * Z11 Z12 Z21 Z22 Z13 Z14 Z23 Z24 ...
+ * Z31 Z32 Z41 Z42 Z33 Z34 Z43 Z44 ...
+ * ... ... ... ... ... ... ... ... ...
+ *
+ * FIXME: Code generate stencil test
+ *
+ * @author Jose Fonseca <jfonseca@vmware.com>
+ */
+
+#include "pipe/p_state.h"
+#include "util/u_format.h"
+
+#include "lp_bld_type.h"
+#include "lp_bld_const.h"
+#include "lp_bld_logic.h"
+#include "lp_bld_flow.h"
+#include "lp_bld_debug.h"
+#include "lp_bld_depth.h"
+
+
+/**
+ * Return a type appropriate for depth/stencil testing.
+ */
+struct lp_type
+lp_depth_type(const struct util_format_description *format_desc,
+ unsigned length)
+{
+ struct lp_type type;
+ unsigned swizzle;
+
+ assert(format_desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS);
+ assert(format_desc->block.width == 1);
+ assert(format_desc->block.height == 1);
+
+ swizzle = format_desc->swizzle[0];
+ assert(swizzle < 4);
+
+ memset(&type, 0, sizeof type);
+ type.width = format_desc->block.bits;
+
+ if(format_desc->channel[swizzle].type == UTIL_FORMAT_TYPE_FLOAT) {
+ type.floating = TRUE;
+ assert(swizzle == 0);
+ assert(format_desc->channel[swizzle].size == format_desc->block.bits);
+ }
+ else if(format_desc->channel[swizzle].type == UTIL_FORMAT_TYPE_UNSIGNED) {
+ assert(format_desc->block.bits <= 32);
+ if(format_desc->channel[swizzle].normalized)
+ type.norm = TRUE;
+ }
+ else
+ assert(0);
+
+ assert(type.width <= length);
+ type.length = length / type.width;
+
+ return type;
+}
+
+
+/**
+ * Depth test.
+ */
+void
+lp_build_depth_test(LLVMBuilderRef builder,
+ const struct pipe_depth_state *state,
+ struct lp_type type,
+ const struct util_format_description *format_desc,
+ struct lp_build_mask_context *mask,
+ LLVMValueRef src,
+ LLVMValueRef dst_ptr)
+{
+ struct lp_build_context bld;
+ unsigned z_swizzle;
+ LLVMValueRef dst;
+ LLVMValueRef z_bitmask = NULL;
+ LLVMValueRef test;
+
+ if(!state->enabled)
+ return;
+
+ assert(format_desc->colorspace == UTIL_FORMAT_COLORSPACE_ZS);
+ assert(format_desc->block.width == 1);
+ assert(format_desc->block.height == 1);
+
+ z_swizzle = format_desc->swizzle[0];
+ if(z_swizzle == UTIL_FORMAT_SWIZZLE_NONE)
+ return;
+
+ /* Sanity checking */
+ assert(z_swizzle < 4);
+ assert(format_desc->block.bits == type.width);
+ if(type.floating) {
+ assert(z_swizzle == 0);
+ assert(format_desc->channel[z_swizzle].type == UTIL_FORMAT_TYPE_FLOAT);
+ assert(format_desc->channel[z_swizzle].size == format_desc->block.bits);
+ }
+ else {
+ assert(format_desc->channel[z_swizzle].type == UTIL_FORMAT_TYPE_UNSIGNED);
+ assert(format_desc->channel[z_swizzle].normalized);
+ assert(!type.fixed);
+ assert(!type.sign);
+ assert(type.norm);
+ }
+
+ /* Setup build context */
+ lp_build_context_init(&bld, builder, type);
+
+ dst = LLVMBuildLoad(builder, dst_ptr, "");
+
+ lp_build_name(dst, "zsbuf");
+
+ /* Align the source depth bits with the destination's, and mask out any
+ * stencil or padding bits from both */
+ if(format_desc->channel[z_swizzle].size == format_desc->block.bits) {
+ assert(z_swizzle == 0);
+ /* nothing to do */
+ }
+ else {
+ unsigned padding_left;
+ unsigned padding_right;
+ unsigned chan;
+
+ assert(format_desc->layout == UTIL_FORMAT_LAYOUT_ARITH);
+ assert(format_desc->channel[z_swizzle].type == UTIL_FORMAT_TYPE_UNSIGNED);
+ assert(format_desc->channel[z_swizzle].size <= format_desc->block.bits);
+ assert(format_desc->channel[z_swizzle].normalized);
+
+ padding_right = 0;
+ for(chan = 0; chan < z_swizzle; ++chan)
+ padding_right += format_desc->channel[chan].size;
+ padding_left = format_desc->block.bits -
+ (padding_right + format_desc->channel[z_swizzle].size);
+
+ if(padding_left || padding_right) {
+ const unsigned long long mask_left = ((unsigned long long)1 << (format_desc->block.bits - padding_left)) - 1;
+ const unsigned long long mask_right = ((unsigned long long)1 << (padding_right)) - 1;
+ z_bitmask = lp_build_int_const_scalar(type, mask_left ^ mask_right);
+ }
+
+ if(padding_left)
+ src = LLVMBuildLShr(builder, src, lp_build_int_const_scalar(type, padding_left), "");
+ if(padding_right)
+ src = LLVMBuildAnd(builder, src, z_bitmask, "");
+ if(padding_left || padding_right)
+ dst = LLVMBuildAnd(builder, dst, z_bitmask, "");
+ }
+
+ lp_build_name(dst, "zsbuf.z");
+
+ test = lp_build_cmp(&bld, state->func, src, dst);
+ lp_build_mask_update(mask, test);
+
+ if(state->writemask) {
+ if(z_bitmask)
+ z_bitmask = LLVMBuildAnd(builder, mask->value, z_bitmask, "");
+ else
+ z_bitmask = mask->value;
+
+ dst = lp_build_select(&bld, z_bitmask, src, dst);
+ LLVMBuildStore(builder, dst, dst_ptr);
+ }
+}