llvmpipe: Implement stencil export

Pretty trivial, fixes the issue that we're expected to be able to blit
stencil surfaces (as the blit just relies on util blitter code which needs
stencil export to do it).
2 piglits skip->pass, 11 fail->pass

v2: prettify, keep different stencil ref value handling out of depth/stencil
test itself.

Reviewed-by: Jose Fonseca <jfonseca@vmware.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>

diff --git a/src/gallium/drivers/llvmpipe/lp_bld_depth.c b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
index b6c32ffb979b0f216b7823f06c149e9bbc4d300e..b25e041375070a4bdc2209b2c2a722a723775bb1 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_bld_depth.c
+++ b/src/gallium/drivers/llvmpipe/lp_bld_depth.c
@@ -975,10 +975,6 @@ lp_build_depth_stencil_test(struct gallivm_state *gallivm,
                                          s_bld.int_vec_type, "");
       }
 
-      /* convert scalar stencil refs into vectors */
-      stencil_refs[0] = lp_build_broadcast_scalar(&s_bld, stencil_refs[0]);
-      stencil_refs[1] = lp_build_broadcast_scalar(&s_bld, stencil_refs[1]);
-
       s_pass_mask = lp_build_stencil_test(&s_bld, stencil,
                                           stencil_refs, stencil_vals,
                                           front_facing);

diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
index 09ac9af50ec412d2f54c7151e7a521f814257d74..47f1897c7324570457f933449e342c15f8b9b5cd 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_screen.c
+++ b/src/gallium/drivers/llvmpipe/lp_screen.c
@@ -165,7 +165,7 @@ llvmpipe_get_param(struct pipe_screen *screen, enum pipe_cap param)
    case PIPE_CAP_DEPTH_CLIP_DISABLE:
       return 1;
    case PIPE_CAP_SHADER_STENCIL_EXPORT:
-      return 0;
+      return 1;
    case PIPE_CAP_TGSI_INSTANCEID:
    case PIPE_CAP_VERTEX_ELEMENT_INSTANCE_DIVISOR:
    case PIPE_CAP_START_INSTANCE:

diff --git a/src/gallium/drivers/llvmpipe/lp_state_fs.c b/src/gallium/drivers/llvmpipe/lp_state_fs.c
index 35fe7b201810b07e37b8d9bf56ec389853bf62da..b5ce8683f1a50ccb58bf030015179eb498c1dc28 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_state_fs.c
+++ b/src/gallium/drivers/llvmpipe/lp_state_fs.c
@@ -260,7 +260,8 @@ generate_fs_loop(struct gallivm_state *gallivm,
 {
    const struct util_format_description *zs_format_desc = NULL;
    const struct tgsi_token *tokens = shader->base.tokens;
-   LLVMTypeRef vec_type;
+   struct lp_type int_type = lp_int_type(type);
+   LLVMTypeRef vec_type, int_vec_type;
    LLVMValueRef mask_ptr, mask_val;
    LLVMValueRef consts_ptr, num_consts_ptr;
    LLVMValueRef z;
@@ -295,7 +296,7 @@ generate_fs_loop(struct gallivm_state *gallivm,
       zs_format_desc = util_format_description(key->zsbuf_format);
       assert(zs_format_desc);
 
-      if (!shader->info.base.writes_z) {
+      if (!shader->info.base.writes_z && !shader->info.base.writes_stencil) {
          if (key->alpha.enabled ||
              key->blend.alpha_to_coverage ||
              shader->info.base.uses_kill) {
@@ -329,11 +330,14 @@ generate_fs_loop(struct gallivm_state *gallivm,
       depth_mode = 0;
    }
 
+   vec_type = lp_build_vec_type(gallivm, type);
+   int_vec_type = lp_build_vec_type(gallivm, int_type);
 
    stencil_refs[0] = lp_jit_context_stencil_ref_front_value(gallivm, context_ptr);
    stencil_refs[1] = lp_jit_context_stencil_ref_back_value(gallivm, context_ptr);
-
-   vec_type = lp_build_vec_type(gallivm, type);
+   /* convert scalar stencil refs into vectors */
+   stencil_refs[0] = lp_build_broadcast(gallivm, int_vec_type, stencil_refs[0]);
+   stencil_refs[1] = lp_build_broadcast(gallivm, int_vec_type, stencil_refs[1]);
 
    consts_ptr = lp_jit_context_constants(gallivm, context_ptr);
    num_consts_ptr = lp_jit_context_num_constants(gallivm, context_ptr);
@@ -462,7 +466,9 @@ generate_fs_loop(struct gallivm_state *gallivm,
       int pos0 = find_output_by_semantic(&shader->info.base,
                                          TGSI_SEMANTIC_POSITION,
                                          0);
-
+      int s_out = find_output_by_semantic(&shader->info.base,
+                                          TGSI_SEMANTIC_STENCIL,
+                                          0);
       if (pos0 != -1 && outputs[pos0][2]) {
          z = LLVMBuildLoad(builder, outputs[pos0][2], "output.z");
 
@@ -512,6 +518,15 @@ generate_fs_loop(struct gallivm_state *gallivm,
          }
       }
 
+      if (s_out != -1 && outputs[s_out][1]) {
+         /* there's only one value, and spec says to discard additional bits */
+         LLVMValueRef s_max_mask = lp_build_const_int_vec(gallivm, int_type, 255);
+         stencil_refs[0] = LLVMBuildLoad(builder, outputs[s_out][1], "output.s");
+         stencil_refs[0] = LLVMBuildBitCast(builder, stencil_refs[0], int_vec_type, "");
+         stencil_refs[0] = LLVMBuildAnd(builder, stencil_refs[0], s_max_mask, "");
+         stencil_refs[1] = stencil_refs[0];
+      }
+
       lp_build_depth_stencil_load_swizzled(gallivm, type,
                                            zs_format_desc, key->resource_1d,
                                            depth_ptr, depth_stride,

diff --git a/src/gallium/drivers/llvmpipe/lp_surface.c b/src/gallium/drivers/llvmpipe/lp_surface.c
index 08f968f7f0a4d86c36dfe501c009b7c62f949211..b985877e43e4a891ba65eaa6e8170319f7fb1b3d 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_surface.c
+++ b/src/gallium/drivers/llvmpipe/lp_surface.c
@@ -139,11 +139,6 @@ static void lp_blit(struct pipe_context *pipe,
       return; /* done */
    }
 
-   if (info.mask & PIPE_MASK_S) {
-      debug_printf("llvmpipe: cannot blit stencil, skipping\n");
-      info.mask &= ~PIPE_MASK_S;
-   }
-
    if (!util_blitter_is_blit_supported(lp->blitter, &info)) {
       debug_printf("llvmpipe: blit unsupported %s -> %s\n",
                    util_format_short_name(info.src.resource->format),