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authorJosé Fonseca <jfonseca@vmware.com>2009-10-22 18:28:17 +0100
committerJosé Fonseca <jfonseca@vmware.com>2009-10-22 19:12:13 +0100
commit421507de06bd42a322c5864d887e67e385eb458c (patch)
tree206336e353276210a7f215cd7b767321d0fc49ff /src/gallium
parenta07437f8a6a863654487c5586cbd02bfc20f0a3b (diff)
llvmpipe: Factor vector packing/unpacking to a separate source file.
These functions will be needed to implement many of the 8bit operations, and they are quite complex on its own.
Diffstat (limited to 'src/gallium')
-rw-r--r--src/gallium/drivers/llvmpipe/Makefile1
-rw-r--r--src/gallium/drivers/llvmpipe/SConscript1
-rw-r--r--src/gallium/drivers/llvmpipe/lp_bld_conv.c240
-rw-r--r--src/gallium/drivers/llvmpipe/lp_bld_pack.c419
-rw-r--r--src/gallium/drivers/llvmpipe/lp_bld_pack.h95
5 files changed, 519 insertions, 237 deletions
diff --git a/src/gallium/drivers/llvmpipe/Makefile b/src/gallium/drivers/llvmpipe/Makefile
index 21aff1967a..b96ee23a99 100644
--- a/src/gallium/drivers/llvmpipe/Makefile
+++ b/src/gallium/drivers/llvmpipe/Makefile
@@ -21,6 +21,7 @@ C_SOURCES = \
lp_bld_interp.c \
lp_bld_intr.c \
lp_bld_logic.c \
+ lp_bld_pack.c \
lp_bld_sample_soa.c \
lp_bld_swizzle.c \
lp_bld_struct.c \
diff --git a/src/gallium/drivers/llvmpipe/SConscript b/src/gallium/drivers/llvmpipe/SConscript
index 13cd465838..403e4daa43 100644
--- a/src/gallium/drivers/llvmpipe/SConscript
+++ b/src/gallium/drivers/llvmpipe/SConscript
@@ -33,6 +33,7 @@ llvmpipe = env.ConvenienceLibrary(
'lp_bld_format_soa.c',
'lp_bld_interp.c',
'lp_bld_intr.c',
+ 'lp_bld_pack.c',
'lp_bld_sample_soa.c',
'lp_bld_struct.c',
'lp_bld_logic.c',
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_conv.c b/src/gallium/drivers/llvmpipe/lp_bld_conv.c
index 20c8710214..9935209437 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_conv.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_conv.c
@@ -69,6 +69,7 @@
#include "lp_bld_const.h"
#include "lp_bld_intr.h"
#include "lp_bld_arit.h"
+#include "lp_bld_pack.h"
#include "lp_bld_conv.h"
@@ -199,241 +200,6 @@ lp_build_unsigned_norm_to_float(LLVMBuilderRef builder,
/**
- * Build shuffle vectors that match PUNPCKLxx and PUNPCKHxx instructions.
- */
-static LLVMValueRef
-lp_build_const_unpack_shuffle(unsigned n, unsigned lo_hi)
-{
- LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
- unsigned i, j;
-
- assert(n <= LP_MAX_VECTOR_LENGTH);
- assert(lo_hi < 2);
-
- /* TODO: cache results in a static table */
-
- for(i = 0, j = lo_hi*n/2; i < n; i += 2, ++j) {
- elems[i + 0] = LLVMConstInt(LLVMInt32Type(), 0 + j, 0);
- elems[i + 1] = LLVMConstInt(LLVMInt32Type(), n + j, 0);
- }
-
- return LLVMConstVector(elems, n);
-}
-
-
-/**
- * Build shuffle vectors that match PACKxx instructions.
- */
-static LLVMValueRef
-lp_build_const_pack_shuffle(unsigned n)
-{
- LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
- unsigned i;
-
- assert(n <= LP_MAX_VECTOR_LENGTH);
-
- /* TODO: cache results in a static table */
-
- for(i = 0; i < n; ++i)
- elems[i] = LLVMConstInt(LLVMInt32Type(), 2*i, 0);
-
- return LLVMConstVector(elems, n);
-}
-
-
-/**
- * Expand the bit width.
- *
- * This will only change the number of bits the values are represented, not the
- * values themselves.
- */
-static void
-lp_build_expand(LLVMBuilderRef builder,
- struct lp_type src_type,
- struct lp_type dst_type,
- LLVMValueRef src,
- LLVMValueRef *dst, unsigned num_dsts)
-{
- unsigned num_tmps;
- unsigned i;
-
- /* Register width must remain constant */
- assert(src_type.width * src_type.length == dst_type.width * dst_type.length);
-
- /* We must not loose or gain channels. Only precision */
- assert(src_type.length == dst_type.length * num_dsts);
-
- num_tmps = 1;
- dst[0] = src;
-
- while(src_type.width < dst_type.width) {
- struct lp_type new_type = src_type;
- LLVMTypeRef new_vec_type;
-
- new_type.width *= 2;
- new_type.length /= 2;
- new_vec_type = lp_build_vec_type(new_type);
-
- for(i = num_tmps; i--; ) {
- LLVMValueRef zero;
- LLVMValueRef shuffle_lo;
- LLVMValueRef shuffle_hi;
- LLVMValueRef lo;
- LLVMValueRef hi;
-
- zero = lp_build_zero(src_type);
- shuffle_lo = lp_build_const_unpack_shuffle(src_type.length, 0);
- shuffle_hi = lp_build_const_unpack_shuffle(src_type.length, 1);
-
- /* PUNPCKLBW, PUNPCKHBW */
- lo = LLVMBuildShuffleVector(builder, dst[i], zero, shuffle_lo, "");
- hi = LLVMBuildShuffleVector(builder, dst[i], zero, shuffle_hi, "");
-
- dst[2*i + 0] = LLVMBuildBitCast(builder, lo, new_vec_type, "");
- dst[2*i + 1] = LLVMBuildBitCast(builder, hi, new_vec_type, "");
- }
-
- src_type = new_type;
-
- num_tmps *= 2;
- }
-
- assert(num_tmps == num_dsts);
-}
-
-
-/**
- * Non-interleaved pack.
- *
- * This will move values as
- *
- * lo = __ l0 __ l1 __ l2 __.. __ ln
- * hi = __ h0 __ h1 __ h2 __.. __ hn
- * res = l0 l1 l2 .. ln h0 h1 h2 .. hn
- *
- * TODO: handle saturation consistently.
- */
-static LLVMValueRef
-lp_build_pack2(LLVMBuilderRef builder,
- struct lp_type src_type,
- struct lp_type dst_type,
- boolean clamped,
- LLVMValueRef lo,
- LLVMValueRef hi)
-{
- LLVMTypeRef src_vec_type = lp_build_vec_type(src_type);
- LLVMTypeRef dst_vec_type = lp_build_vec_type(dst_type);
- LLVMValueRef shuffle;
- LLVMValueRef res;
-
- /* Register width must remain constant */
- assert(src_type.width * src_type.length == dst_type.width * dst_type.length);
-
- /* We must not loose or gain channels. Only precision */
- assert(src_type.length * 2 == dst_type.length);
-
- assert(!src_type.floating);
- assert(!dst_type.floating);
-
- if(util_cpu_caps.has_sse2 && src_type.width * src_type.length == 128) {
- /* All X86 non-interleaved pack instructions all take signed inputs and
- * saturate them, so saturate beforehand. */
- if(!src_type.sign && !clamped) {
- struct lp_build_context bld;
- unsigned dst_bits = dst_type.sign ? dst_type.width - 1 : dst_type.width;
- LLVMValueRef dst_max = lp_build_int_const_scalar(src_type, ((unsigned long long)1 << dst_bits) - 1);
- lp_build_context_init(&bld, builder, src_type);
- lo = lp_build_min(&bld, lo, dst_max);
- hi = lp_build_min(&bld, hi, dst_max);
- }
-
- switch(src_type.width) {
- case 32:
- if(dst_type.sign || !util_cpu_caps.has_sse4_1)
- res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packssdw.128", src_vec_type, lo, hi);
- else
- /* PACKUSDW is the only instrinsic with a consistent signature */
- return lp_build_intrinsic_binary(builder, "llvm.x86.sse41.packusdw", dst_vec_type, lo, hi);
- break;
-
- case 16:
- if(dst_type.sign)
- res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packsswb.128", src_vec_type, lo, hi);
- else
- res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packuswb.128", src_vec_type, lo, hi);
- break;
-
- default:
- assert(0);
- return LLVMGetUndef(dst_vec_type);
- break;
- }
-
- res = LLVMBuildBitCast(builder, res, dst_vec_type, "");
- return res;
- }
-
- lo = LLVMBuildBitCast(builder, lo, dst_vec_type, "");
- hi = LLVMBuildBitCast(builder, hi, dst_vec_type, "");
-
- shuffle = lp_build_const_pack_shuffle(dst_type.length);
-
- res = LLVMBuildShuffleVector(builder, lo, hi, shuffle, "");
-
- return res;
-}
-
-
-/**
- * Truncate the bit width.
- *
- * TODO: Handle saturation consistently.
- */
-static LLVMValueRef
-lp_build_pack(LLVMBuilderRef builder,
- struct lp_type src_type,
- struct lp_type dst_type,
- boolean clamped,
- const LLVMValueRef *src, unsigned num_srcs)
-{
- LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH];
- unsigned i;
-
- /* Register width must remain constant */
- assert(src_type.width * src_type.length == dst_type.width * dst_type.length);
-
- /* We must not loose or gain channels. Only precision */
- assert(src_type.length * num_srcs == dst_type.length);
-
- for(i = 0; i < num_srcs; ++i)
- tmp[i] = src[i];
-
- while(src_type.width > dst_type.width) {
- struct lp_type new_type = src_type;
-
- new_type.width /= 2;
- new_type.length *= 2;
-
- /* Take in consideration the sign changes only in the last step */
- if(new_type.width == dst_type.width)
- new_type.sign = dst_type.sign;
-
- num_srcs /= 2;
-
- for(i = 0; i < num_srcs; ++i)
- tmp[i] = lp_build_pack2(builder, src_type, new_type, clamped,
- tmp[2*i + 0], tmp[2*i + 1]);
-
- src_type = new_type;
- }
-
- assert(num_srcs == 1);
-
- return tmp[0];
-}
-
-
-/**
* Generic type conversion.
*
* TODO: Take a precision argument, or even better, add a new precision member
@@ -572,7 +338,7 @@ lp_build_conv(LLVMBuilderRef builder,
if(tmp_type.width < dst_type.width) {
assert(num_tmps == 1);
- lp_build_expand(builder, tmp_type, dst_type, tmp[0], tmp, num_dsts);
+ lp_build_unpack(builder, tmp_type, dst_type, tmp[0], tmp, num_dsts);
tmp_type.width = dst_type.width;
tmp_type.length = dst_type.length;
num_tmps = num_dsts;
@@ -692,7 +458,7 @@ lp_build_conv_mask(LLVMBuilderRef builder,
}
else if(src_type.width < dst_type.width) {
assert(num_srcs == 1);
- lp_build_expand(builder, src_type, dst_type, src[0], dst, num_dsts);
+ lp_build_unpack(builder, src_type, dst_type, src[0], dst, num_dsts);
}
else {
assert(num_srcs == num_dsts);
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_pack.c b/src/gallium/drivers/llvmpipe/lp_bld_pack.c
new file mode 100644
index 0000000000..fe82fda039
--- /dev/null
+++ b/src/gallium/drivers/llvmpipe/lp_bld_pack.c
@@ -0,0 +1,419 @@
+/**************************************************************************
+ *
+ * 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
+ * Helper functions for packing/unpacking.
+ *
+ * Pack/unpacking is necessary for conversion between types of different
+ * bit width.
+ *
+ * They are also commonly used when an computation needs higher
+ * precision for the intermediate values. For example, if one needs the
+ * function:
+ *
+ * c = compute(a, b);
+ *
+ * to use more precision for intermediate results then one should implement it
+ * as:
+ *
+ * LLVMValueRef
+ * compute(LLVMBuilderRef builder struct lp_type type, LLVMValueRef a, LLVMValueRef b)
+ * {
+ * struct lp_type wide_type = lp_wider_type(type);
+ * LLVMValueRef al, ah, bl, bh, cl, ch, c;
+ *
+ * lp_build_unpack2(builder, type, wide_type, a, &al, &ah);
+ * lp_build_unpack2(builder, type, wide_type, b, &bl, &bh);
+ *
+ * cl = compute_half(al, bl);
+ * ch = compute_half(ah, bh);
+ *
+ * c = lp_build_pack2(bld->builder, wide_type, type, cl, ch);
+ *
+ * return c;
+ * }
+ *
+ * where compute_half() would do the computation for half the elements with
+ * twice the precision.
+ *
+ * @author Jose Fonseca <jfonseca@vmware.com>
+ */
+
+
+#include "util/u_debug.h"
+#include "util/u_math.h"
+#include "util/u_cpu_detect.h"
+
+#include "lp_bld_type.h"
+#include "lp_bld_const.h"
+#include "lp_bld_intr.h"
+#include "lp_bld_arit.h"
+#include "lp_bld_pack.h"
+
+
+/**
+ * Build shuffle vectors that match PUNPCKLxx and PUNPCKHxx instructions.
+ */
+static LLVMValueRef
+lp_build_const_unpack_shuffle(unsigned n, unsigned lo_hi)
+{
+ LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
+ unsigned i, j;
+
+ assert(n <= LP_MAX_VECTOR_LENGTH);
+ assert(lo_hi < 2);
+
+ /* TODO: cache results in a static table */
+
+ for(i = 0, j = lo_hi*n/2; i < n; i += 2, ++j) {
+ elems[i + 0] = LLVMConstInt(LLVMInt32Type(), 0 + j, 0);
+ elems[i + 1] = LLVMConstInt(LLVMInt32Type(), n + j, 0);
+ }
+
+ return LLVMConstVector(elems, n);
+}
+
+
+/**
+ * Build shuffle vectors that match PACKxx instructions.
+ */
+static LLVMValueRef
+lp_build_const_pack_shuffle(unsigned n)
+{
+ LLVMValueRef elems[LP_MAX_VECTOR_LENGTH];
+ unsigned i;
+
+ assert(n <= LP_MAX_VECTOR_LENGTH);
+
+ /* TODO: cache results in a static table */
+
+ for(i = 0; i < n; ++i)
+ elems[i] = LLVMConstInt(LLVMInt32Type(), 2*i, 0);
+
+ return LLVMConstVector(elems, n);
+}
+
+
+/**
+ * Interleave vector elements.
+ *
+ * Matches the PUNPCKLxx and PUNPCKHxx SSE instructions.
+ */
+LLVMValueRef
+lp_build_interleave2(LLVMBuilderRef builder,
+ struct lp_type type,
+ LLVMValueRef a,
+ LLVMValueRef b,
+ unsigned lo_hi)
+{
+ LLVMValueRef shuffle;
+
+ shuffle = lp_build_const_unpack_shuffle(type.length, lo_hi);
+
+ return LLVMBuildShuffleVector(builder, a, b, shuffle, "");
+}
+
+
+/**
+ * Double the bit width.
+ *
+ * This will only change the number of bits the values are represented, not the
+ * values themselves.
+ */
+void
+lp_build_unpack2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef src,
+ LLVMValueRef *dst_lo,
+ LLVMValueRef *dst_hi)
+{
+ LLVMValueRef msb;
+ LLVMTypeRef dst_vec_type;
+
+ assert(!src_type.floating);
+ assert(!dst_type.floating);
+ assert(dst_type.sign == src_type.sign);
+ assert(dst_type.width == src_type.width * 2);
+ assert(dst_type.length * 2 == src_type.length);
+
+ if(src_type.sign) {
+ /* Replicate the sign bit in the most significant bits */
+ msb = LLVMBuildAShr(builder, src, lp_build_int_const_scalar(src_type, src_type.width - 1), "");
+ }
+ else
+ /* Most significant bits always zero */
+ msb = lp_build_zero(src_type);
+
+ /* Interleave bits */
+ if(util_cpu_caps.little_endian) {
+ *dst_lo = lp_build_interleave2(builder, src_type, src, msb, 0);
+ *dst_hi = lp_build_interleave2(builder, src_type, src, msb, 1);
+ }
+ else {
+ *dst_lo = lp_build_interleave2(builder, src_type, msb, src, 0);
+ *dst_hi = lp_build_interleave2(builder, src_type, msb, src, 1);
+ }
+
+ /* Cast the result into the new type (twice as wide) */
+
+ dst_vec_type = lp_build_vec_type(dst_type);
+
+ *dst_lo = LLVMBuildBitCast(builder, *dst_lo, dst_vec_type, "");
+ *dst_hi = LLVMBuildBitCast(builder, *dst_hi, dst_vec_type, "");
+}
+
+
+/**
+ * Expand the bit width.
+ *
+ * This will only change the number of bits the values are represented, not the
+ * values themselves.
+ */
+void
+lp_build_unpack(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef src,
+ LLVMValueRef *dst, unsigned num_dsts)
+{
+ unsigned num_tmps;
+ unsigned i;
+
+ /* Register width must remain constant */
+ assert(src_type.width * src_type.length == dst_type.width * dst_type.length);
+
+ /* We must not loose or gain channels. Only precision */
+ assert(src_type.length == dst_type.length * num_dsts);
+
+ num_tmps = 1;
+ dst[0] = src;
+
+ while(src_type.width < dst_type.width) {
+ struct lp_type tmp_type = src_type;
+
+ tmp_type.width *= 2;
+ tmp_type.length /= 2;
+
+ for(i = num_tmps; i--; ) {
+ lp_build_unpack2(builder, src_type, tmp_type, dst[i], &dst[2*i + 0], &dst[2*i + 1]);
+ }
+
+ src_type = tmp_type;
+
+ num_tmps *= 2;
+ }
+
+ assert(num_tmps == num_dsts);
+}
+
+
+/**
+ * Non-interleaved pack.
+ *
+ * This will move values as
+ *
+ * lo = __ l0 __ l1 __ l2 __.. __ ln
+ * hi = __ h0 __ h1 __ h2 __.. __ hn
+ * res = l0 l1 l2 .. ln h0 h1 h2 .. hn
+ *
+ * This will only change the number of bits the values are represented, not the
+ * values themselves.
+ *
+ * It is assumed the values are already clamped into the destination type range.
+ * Values outside that range will produce undefined results. Use
+ * lp_build_packs2 instead.
+ */
+LLVMValueRef
+lp_build_pack2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef lo,
+ LLVMValueRef hi)
+{
+ LLVMTypeRef src_vec_type = lp_build_vec_type(src_type);
+ LLVMTypeRef dst_vec_type = lp_build_vec_type(dst_type);
+ LLVMValueRef shuffle;
+ LLVMValueRef res;
+
+ dst_vec_type = lp_build_vec_type(dst_type);
+
+ assert(!src_type.floating);
+ assert(!dst_type.floating);
+ assert(src_type.width == dst_type.width * 2);
+ assert(src_type.length * 2 == dst_type.length);
+
+ if(util_cpu_caps.has_sse2 && src_type.width * src_type.length == 128) {
+ switch(src_type.width) {
+ case 32:
+ if(dst_type.sign) {
+ res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packssdw.128", src_vec_type, lo, hi);
+ }
+ else {
+ if (util_cpu_caps.has_sse4_1) {
+ /* PACKUSDW is the only instrinsic with a consistent signature */
+ return lp_build_intrinsic_binary(builder, "llvm.x86.sse41.packusdw", dst_vec_type, lo, hi);
+ }
+ else {
+ assert(0);
+ return LLVMGetUndef(dst_vec_type);
+ }
+ }
+ break;
+
+ case 16:
+ if(dst_type.sign)
+ res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packsswb.128", src_vec_type, lo, hi);
+ else
+ res = lp_build_intrinsic_binary(builder, "llvm.x86.sse2.packuswb.128", src_vec_type, lo, hi);
+ break;
+
+ default:
+ assert(0);
+ return LLVMGetUndef(dst_vec_type);
+ break;
+ }
+
+ res = LLVMBuildBitCast(builder, res, dst_vec_type, "");
+ return res;
+ }
+
+ lo = LLVMBuildBitCast(builder, lo, dst_vec_type, "");
+ hi = LLVMBuildBitCast(builder, hi, dst_vec_type, "");
+
+ shuffle = lp_build_const_pack_shuffle(dst_type.length);
+
+ res = LLVMBuildShuffleVector(builder, lo, hi, shuffle, "");
+
+ return res;
+}
+
+
+
+/**
+ * Non-interleaved pack and saturate.
+ *
+ * Same as lp_build_pack2 but will saturate values so that they fit into the
+ * destination type.
+ */
+LLVMValueRef
+lp_build_packs2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef lo,
+ LLVMValueRef hi)
+{
+ boolean clamp;
+
+ assert(!src_type.floating);
+ assert(!dst_type.floating);
+ assert(src_type.sign == dst_type.sign);
+ assert(src_type.width == dst_type.width * 2);
+ assert(src_type.length * 2 == dst_type.length);
+
+ clamp = TRUE;
+
+ /* All X86 SSE non-interleaved pack instructions take signed inputs and
+ * saturate them, so no need to clamp for those cases. */
+ if(util_cpu_caps.has_sse2 &&
+ src_type.width * src_type.length == 128 &&
+ src_type.sign)
+ clamp = FALSE;
+
+ if(clamp) {
+ struct lp_build_context bld;
+ unsigned dst_bits = dst_type.sign ? dst_type.width - 1 : dst_type.width;
+ LLVMValueRef dst_max = lp_build_int_const_scalar(src_type, ((unsigned long long)1 << dst_bits) - 1);
+ lp_build_context_init(&bld, builder, src_type);
+ lo = lp_build_min(&bld, lo, dst_max);
+ hi = lp_build_min(&bld, hi, dst_max);
+ /* FIXME: What about lower bound? */
+ }
+
+ return lp_build_pack2(builder, src_type, dst_type, lo, hi);
+}
+
+
+/**
+ * Truncate the bit width.
+ *
+ * TODO: Handle saturation consistently.
+ */
+LLVMValueRef
+lp_build_pack(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ boolean clamped,
+ const LLVMValueRef *src, unsigned num_srcs)
+{
+ LLVMValueRef (*pack2)(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef lo,
+ LLVMValueRef hi);
+ LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH];
+ unsigned i;
+
+
+ /* Register width must remain constant */
+ assert(src_type.width * src_type.length == dst_type.width * dst_type.length);
+
+ /* We must not loose or gain channels. Only precision */
+ assert(src_type.length * num_srcs == dst_type.length);
+
+ if(clamped)
+ pack2 = &lp_build_pack2;
+ else
+ pack2 = &lp_build_packs2;
+
+ for(i = 0; i < num_srcs; ++i)
+ tmp[i] = src[i];
+
+ while(src_type.width > dst_type.width) {
+ struct lp_type tmp_type = src_type;
+
+ tmp_type.width /= 2;
+ tmp_type.length *= 2;
+
+ /* Take in consideration the sign changes only in the last step */
+ if(tmp_type.width == dst_type.width)
+ tmp_type.sign = dst_type.sign;
+
+ num_srcs /= 2;
+
+ for(i = 0; i < num_srcs; ++i)
+ tmp[i] = pack2(builder, src_type, tmp_type, tmp[2*i + 0], tmp[2*i + 1]);
+
+ src_type = tmp_type;
+ }
+
+ assert(num_srcs == 1);
+
+ return tmp[0];
+}
diff --git a/src/gallium/drivers/llvmpipe/lp_bld_pack.h b/src/gallium/drivers/llvmpipe/lp_bld_pack.h
new file mode 100644
index 0000000000..fb2a34984a
--- /dev/null
+++ b/src/gallium/drivers/llvmpipe/lp_bld_pack.h
@@ -0,0 +1,95 @@
+/**************************************************************************
+ *
+ * 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
+ * Helper functions for packing/unpacking conversions.
+ *
+ * @author Jose Fonseca <jfonseca@vmware.com>
+ */
+
+
+#ifndef LP_BLD_PACK_H
+#define LP_BLD_PACK_H
+
+
+#include <llvm-c/Core.h>
+
+
+struct lp_type;
+
+
+LLVMValueRef
+lp_build_interleave2(LLVMBuilderRef builder,
+ struct lp_type type,
+ LLVMValueRef a,
+ LLVMValueRef b,
+ unsigned lo_hi);
+
+
+void
+lp_build_unpack2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef src,
+ LLVMValueRef *dst_lo,
+ LLVMValueRef *dst_hi);
+
+
+void
+lp_build_unpack(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef src,
+ LLVMValueRef *dst, unsigned num_dsts);
+
+
+LLVMValueRef
+lp_build_packs2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef lo,
+ LLVMValueRef hi);
+
+
+LLVMValueRef
+lp_build_pack2(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ LLVMValueRef lo,
+ LLVMValueRef hi);
+
+
+LLVMValueRef
+lp_build_pack(LLVMBuilderRef builder,
+ struct lp_type src_type,
+ struct lp_type dst_type,
+ boolean clamped,
+ const LLVMValueRef *src, unsigned num_srcs);
+
+
+#endif /* !LP_BLD_PACK_H */