llvmpipe: Factor out and optimize the input interpolation.

Special attention is given to the interpolation of side by side quads.
Multiplications are made only for the first quad. Interpolation of
inputs for posterior quads are done exclusively with additions, and
perspective divide if necessary.

1 files changed, 8 insertions, 98 deletions

diff --git a/src/gallium/drivers/llvmpipe/lp_bld_tgsi_soa.c b/src/gallium/drivers/llvmpipe/lp_bld_tgsi_soa.c
index 60cf5e9af7..1335ba862e 100644
--- a/src/gallium/drivers/llvmpipe/lp_bld_tgsi_soa.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_tgsi_soa.c
@@ -83,19 +83,12 @@ struct lp_build_tgsi_soa_context
 {
    struct lp_build_context base;
 
-   LLVMValueRef x, y, w;
-   LLVMValueRef a0_ptr;
-   LLVMValueRef dadx_ptr;
-   LLVMValueRef dady_ptr;
-
    LLVMValueRef consts_ptr;
+   const LLVMValueRef *pos;
+   const LLVMValueRef (*inputs)[NUM_CHANNELS];
    LLVMValueRef (*outputs)[NUM_CHANNELS];
    LLVMValueRef samplers_ptr;
 
-   LLVMValueRef oow;
-
-   LLVMValueRef inputs[PIPE_MAX_SHADER_INPUTS][NUM_CHANNELS];
-
    LLVMValueRef immediates[LP_MAX_IMMEDIATES][NUM_CHANNELS];
    LLVMValueRef temps[LP_MAX_TEMPS][NUM_CHANNELS];
 
@@ -1350,93 +1343,16 @@ emit_instruction(
    return 1;
 }
 
-static void
-emit_declaration(
-   struct lp_build_tgsi_soa_context *bld,
-   struct tgsi_full_declaration *decl )
-{
-   if( decl->Declaration.File == TGSI_FILE_INPUT ) {
-      LLVMBuilderRef builder = bld->base.builder;
-      unsigned first, last, mask;
-      unsigned attrib, chan;
-
-      first = decl->DeclarationRange.First;
-      last = decl->DeclarationRange.Last;
-      mask = decl->Declaration.UsageMask;
-
-      for( attrib = first; attrib <= last; attrib++ ) {
-         for( chan = 0; chan < NUM_CHANNELS; chan++ ) {
-            LLVMValueRef input = bld->base.undef;
-
-            if( mask & (1 << chan) ) {
-               LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), (1 + attrib)*NUM_CHANNELS + chan, 0);
-               LLVMValueRef a0;
-               LLVMValueRef dadx;
-               LLVMValueRef dady;
-
-               switch( decl->Declaration.Interpolate ) {
-               case TGSI_INTERPOLATE_PERSPECTIVE:
-                  /* fall-through */
-
-               case TGSI_INTERPOLATE_LINEAR: {
-                  LLVMValueRef dadx_ptr = LLVMBuildGEP(builder, bld->dadx_ptr, &index, 1, "");
-                  LLVMValueRef dady_ptr = LLVMBuildGEP(builder, bld->dady_ptr, &index, 1, "");
-                  dadx = LLVMBuildLoad(builder, dadx_ptr, "");
-                  dady = LLVMBuildLoad(builder, dady_ptr, "");
-                  dadx = lp_build_broadcast_scalar(&bld->base, dadx);
-                  dady = lp_build_broadcast_scalar(&bld->base, dady);
-                  lp_build_name(dadx, "dadx_%u.%c", attrib, "xyzw"[chan]);
-                  lp_build_name(dady, "dady_%u.%c", attrib, "xyzw"[chan]);
-                  /* fall-through */
-               }
-
-               case TGSI_INTERPOLATE_CONSTANT: {
-                  LLVMValueRef a0_ptr = LLVMBuildGEP(builder, bld->a0_ptr, &index, 1, "");
-                  a0 = LLVMBuildLoad(builder, a0_ptr, "");
-                  a0 = lp_build_broadcast_scalar(&bld->base, a0);
-                  lp_build_name(a0, "a0_%u.%c", attrib, "xyzw"[chan]);
-                  break;
-               }
-
-               default:
-                  assert(0);
-                  break;
-               }
-
-               input = a0;
-
-               if (decl->Declaration.Interpolate != TGSI_INTERPOLATE_CONSTANT) {
-                  input = lp_build_add(&bld->base, input, lp_build_mul(&bld->base, bld->x, dadx));
-                  input = lp_build_add(&bld->base, input, lp_build_mul(&bld->base, bld->y, dady));
-               }
-
-               if (decl->Declaration.Interpolate == TGSI_INTERPOLATE_PERSPECTIVE) {
-                  if(!bld->oow)
-                     bld->oow = lp_build_rcp(&bld->base, bld->w);
-                  input = lp_build_mul(&bld->base, input, bld->oow);
-               }
-
-               lp_build_name(input, "input%u.%c", attrib, "xyzw"[chan]);
-            }
-
-            bld->inputs[attrib][chan] = input;
-         }
-      }
-   }
-}
-
 
 void
 lp_build_tgsi_soa(LLVMBuilderRef builder,
                   const struct tgsi_token *tokens,
                   union lp_type type,
                   struct lp_build_mask_context *mask,
-                  LLVMValueRef *pos,
-                  LLVMValueRef a0_ptr,
-                  LLVMValueRef dadx_ptr,
-                  LLVMValueRef dady_ptr,
                   LLVMValueRef consts_ptr,
-                  LLVMValueRef (*outputs)[4],
+                  const LLVMValueRef *pos,
+                  const LLVMValueRef (*inputs)[NUM_CHANNELS],
+                  LLVMValueRef (*outputs)[NUM_CHANNELS],
                   LLVMValueRef samplers_ptr)
 {
    struct lp_build_tgsi_soa_context bld;
@@ -1448,12 +1364,8 @@ lp_build_tgsi_soa(LLVMBuilderRef builder,
    memset(&bld, 0, sizeof bld);
    lp_build_context_init(&bld.base, builder, type);
    bld.mask = mask;
-   bld.x = pos[0];
-   bld.y = pos[1];
-   bld.w = pos[3];
-   bld.a0_ptr = a0_ptr;
-   bld.dadx_ptr = dadx_ptr;
-   bld.dady_ptr = dady_ptr;
+   bld.pos = pos;
+   bld.inputs = inputs;
    bld.outputs = outputs;
    bld.consts_ptr = consts_ptr;
    bld.samplers_ptr = samplers_ptr;
@@ -1465,9 +1377,7 @@ lp_build_tgsi_soa(LLVMBuilderRef builder,
 
       switch( parse.FullToken.Token.Type ) {
       case TGSI_TOKEN_TYPE_DECLARATION:
-         if (parse.FullHeader.Processor.Processor == TGSI_PROCESSOR_FRAGMENT) {
-            emit_declaration( &bld, &parse.FullToken.FullDeclaration );
-         }
+         /* Input already interpolated */
          break;
 
       case TGSI_TOKEN_TYPE_INSTRUCTION: