llvmpipe: export the tgsi translation code to a common layer

the llvmpipe tgsi translation is a lot more complete than what was in
gallivm so replacing the latter with the former. this is needed since
the draw llvm paths will use the same code. effectively the proven
llvmpipe code becomes gallivm.

1 files changed, 418 insertions, 0 deletions

diff --git a/src/gallium/auxiliary/gallivm/lp_bld_pack.c b/src/gallium/auxiliary/gallivm/lp_bld_pack.c
new file mode 100644
index 0000000000..bc360ad77a
--- /dev/null
+++ b/src/gallium/auxiliary/gallivm/lp_bld_pack.c
@@ -0,0 +1,418 @@
+/**************************************************************************
+ *
+ * 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.width == src_type.width * 2);
+   assert(dst_type.length * 2 == src_type.length);
+
+   if(dst_type.sign && 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];
+}