draw: remove clip_vertex from vertex header

vertex header had both clip_pos and clip_vertex.
We only really need one (clip_pos) because the draw llvm shader would
overwrite the position output from the vs with the viewport transformed.
However, we don't really need the second one, which was only really used
for gl_ClipVertex - if the shader didn't have that the values were just
duplicated to both clip_pos and clip_vertex. So, just use this from the vs
output instead when we actually need it.
Also change clip debug to output both the data from clip_pos and the
clipVertex output (if available).
Makes some things more complex, some things less complex, but seems more
easy to understand what clipping actually does (and what values it uses
to do its magic).

Reviewed-by: Brian Paul <[email protected]
Reviewed-by: Jose Fonseca <[email protected]>

1 files changed, 5 insertions, 16 deletions

diff --git a/src/gallium/auxiliary/draw/draw_llvm.c b/src/gallium/auxiliary/draw/draw_llvm.c
index 934f4525381..a966e45d13f 100644
--- a/src/gallium/auxiliary/draw/draw_llvm.c
+++ b/src/gallium/auxiliary/draw/draw_llvm.c
@@ -378,14 +378,13 @@ static LLVMTypeRef
 create_jit_vertex_header(struct gallivm_state *gallivm, int data_elems)
 {
    LLVMTargetDataRef target = gallivm->target;
-   LLVMTypeRef elem_types[4];
+   LLVMTypeRef elem_types[3];
    LLVMTypeRef vertex_header;
    char struct_name[24];
 
    util_snprintf(struct_name, 23, "vertex_header%d", data_elems);
 
    elem_types[DRAW_JIT_VERTEX_VERTEX_ID]  = LLVMIntTypeInContext(gallivm->context, 32);
-   elem_types[DRAW_JIT_VERTEX_CLIP_VERTEX]  = LLVMArrayType(LLVMFloatTypeInContext(gallivm->context), 4);
    elem_types[DRAW_JIT_VERTEX_CLIP_POS]  = LLVMArrayType(LLVMFloatTypeInContext(gallivm->context), 4);
    elem_types[DRAW_JIT_VERTEX_DATA]  = LLVMArrayType(elem_types[1], data_elems);
 
@@ -407,9 +406,6 @@ create_jit_vertex_header(struct gallivm_state *gallivm, int data_elems)
       DRAW_JIT_VERTEX_VERTEX_ID);
    */
    (void) target; /* silence unused var warning for non-debug build */
-   LP_CHECK_MEMBER_OFFSET(struct vertex_header, clip_vertex,
-                          target, vertex_header,
-                          DRAW_JIT_VERTEX_CLIP_VERTEX);
    LP_CHECK_MEMBER_OFFSET(struct vertex_header, clip_pos,
                           target, vertex_header,
                           DRAW_JIT_VERTEX_CLIP_POS);
@@ -1019,7 +1015,7 @@ store_clip(struct gallivm_state *gallivm,
            const struct lp_type vs_type,
            LLVMValueRef io_ptr,
            LLVMValueRef (*outputs)[TGSI_NUM_CHANNELS],
-           boolean clip_vertex, int idx)
+           int idx)
 {
    LLVMBuilderRef builder = gallivm->builder;
    LLVMValueRef soa[4];
@@ -1046,14 +1042,8 @@ store_clip(struct gallivm_state *gallivm,
    soa[2] = LLVMBuildLoad(builder, outputs[idx][2], ""); /*z0 z1 .. zn*/
    soa[3] = LLVMBuildLoad(builder, outputs[idx][3], ""); /*w0 w1 .. wn*/
 
-   if (clip_vertex) {
-      for (i = 0; i < vs_type.length; i++) {
-         clip_ptrs[i] = draw_jit_header_clip_vertex(gallivm, io_ptrs[i]);
-      }
-   } else {
-      for (i = 0; i < vs_type.length; i++) {
-         clip_ptrs[i] = draw_jit_header_clip_pos(gallivm, io_ptrs[i]);
-      }
+   for (i = 0; i < vs_type.length; i++) {
+      clip_ptrs[i] = draw_jit_header_clip_pos(gallivm, io_ptrs[i]);
    }
 
    lp_build_transpose_aos(gallivm, vs_type, soa, soa);
@@ -1771,8 +1761,7 @@ draw_llvm_generate(struct draw_llvm *llvm, struct draw_llvm_variant *variant,
 
       if (pos != -1 && cv != -1) {
          /* store original positions in clip before further manipulation */
-         store_clip(gallivm, vs_type, io, outputs, TRUE, key->clip_user ? cv : pos);
-         store_clip(gallivm, vs_type, io, outputs, FALSE, pos);
+         store_clip(gallivm, vs_type, io, outputs, pos);
 
          /* do cliptest */
          if (enable_cliptest) {