src/glsl/tests/lower_jumps

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#include "util/u_debug.h"

#include "lp_bld_type.h"
#include "lp_bld_const.h"
#include "lp_bld_swizzle.h"


LLVMValueRef
lp_build_broadcast_scalar(struct lp_build_context *bld,
                          LLVMValueRef scalar)
{
   const union lp_type type = bld->type;
   LLVMValueRef res;
   unsigned i;

   res = bld->undef;
   for(i = 0; i < type.length; ++i) {
      LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0);
      res = LLVMBuildInsertElement(bld->builder, res, scalar, index, "");
   }

   return res;
}


LLVMValueRef
lp_build_broadcast_aos(struct lp_build_context *bld,
                       LLVMValueRef a,
                       unsigned channel)
{
   const union lp_type type = bld->type;
   const unsigned n = type.length;
   unsigned i, j;

   if(a == bld->undef || a == bld->zero || a == bld->one)
      return a;

   /* XXX: SSE3 has PSHUFB which should be better than bitmasks, but forcing
    * using shuffles here actually causes worst results. More investigation is
    * needed. */
   if (n <= 4) {
      /*
       * Shuffle.
       */
      LLVMTypeRef elem_type = LLVMInt32Type();
      LLVMValueRef shuffles[LP_MAX_VECTOR_LENGTH];

      for(j = 0; j < n; j += 4)
         for(i = 0; i < 4; ++i)
            shuffles[j + i] = LLVMConstInt(elem_type, j + channel, 0);

      return LLVMBuildShuffleVector(bld->builder, a, bld->undef, LLVMConstVector(shuffles, n), "");
   }
   else {
      /*
       * Bit mask and recursive shifts
       *
       *   XYZW XYZW .... XYZW  <= input
       *   0Y00 0Y00 .... 0Y00
       *   YY00 YY00 .... YY00
       *   YYYY YYYY .... YYYY  <= output
       */
      union lp_type type4 = type;
      const char shifts[4][2] = {
         { 1,  2},
         {-1,  2},
         { 1, -2},
         {-1, -2}
      };
      boolean cond[4];
      unsigned i;

      memset(cond, 0, sizeof cond);
      cond[channel] = 1;

      a = LLVMBuildAnd(bld->builder, a, lp_build_const_mask_aos(type, cond), "");

      type4.width *= 4;
      type4.length /= 4;

      a = LLVMBuildBitCast(bld->builder, a, lp_build_vec_type(type4), "");

      for(i = 0; i < 2; ++i) {
         LLVMValueRef tmp = NULL;
         int shift = shifts[channel][i];

#ifdef PIPE_ARCH_LITTLE_ENDIAN
         shift = -shift;
#endif

         if(shift > 0)
            tmp = LLVMBuildLShr(bld->builder, a, lp_build_int_const_uni(type4, shift*type.width), "");
         if(shift < 0)
            tmp = LLVMBuildShl(bld->builder, a, lp_build_int_const_uni(type4, -shift*type.width), "");

         assert(tmp);
         if(tmp)
            a = LLVMBuildOr(bld->builder, a, tmp, "");
      }

      return LLVMBuildBitCast(bld->builder, a, lp_build_vec_type(type), "");
   }
}


LLVMValueRef
lp_build_select(struct lp_build_context *bld,
                LLVMValueRef mask,
                LLVMValueRef a,
                LLVMValueRef b)
{
   union lp_type type = bld->type;
   LLVMValueRef res;

   if(a == b)
      return a;

   if(type.floating) {
      LLVMTypeRef int_vec_type = lp_build_int_vec_type(type);
      a = LLVMBuildBitCast(bld->builder, a, int_vec_type, "");
      b = LLVMBuildBitCast(bld->builder, b, int_vec_type, "");
   }

   /* TODO: On SSE4 we could do this with a single instruction -- PBLENDVB */

   a = LLVMBuildAnd(bld->builder, a, mask, "");

   /* This often gets translated to PANDN, but sometimes the NOT is
    * pre-computed and stored in another constant. The best strategy depends
    * on available registers, so it is not a big deal -- hopefully LLVM does
    * the right decision attending the rest of the program.
    */
   b = LLVMBuildAnd(bld->builder, b, LLVMBuildNot(bld->builder, mask, ""), "");

   res = LLVMBuildOr(bld->builder, a, b, "");

   if(type.floating) {
      LLVMTypeRef vec_type = lp_build_vec_type(type);
      res = LLVMBuildBitCast(bld->builder, res, vec_type, "");
   }

   return res;
}


LLVMValueRef
lp_build_select_aos(struct lp_build_context *bld,
                    LLVMValueRef a,
                    LLVMValueRef b,
                    boolean cond[4])
{
   const union lp_type type = bld->type;
   const unsigned n = type.length;
   unsigned i, j;

   if(a == b)
      return a;
   if(cond[0] && cond[1] && cond[2] && cond[3])
      return a;
   if(!cond[0] && !cond[1] && !cond[2] && !cond[3])
      return b;
   if(a == bld->undef || b == bld->undef)
      return bld->undef;

   /*
    * There are three major ways of accomplishing this:
Mode	Name	Size
-rw-r--r--	.gitignore	28	log stats plain
-rw-r--r--	create_test_cases.py	25472	log stats plain