d3d12: Enable texture gather

The CI changes are because WARP fails really hard at gather,
with crashes when doing it on a 1x1 or Nx1 texture, and incorrectly
applying swizzling to the result vector instead of the actual texture
accesses.

Reviewed-by: Sil Vilerino <sivileri@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14161>

src/gallium/drivers/d3d12/ci/d3d12-quick_shader.txt

@@ -71,7 +71,6 @@ spec/amd_shader_trinary_minmax/execution/built-in-functions/tcs-min3-uvec4-uvec4
 spec/amd_shader_trinary_minmax/execution/built-in-functions/tcs-min3-vec2-vec2-vec2: skip
 spec/amd_shader_trinary_minmax/execution/built-in-functions/tcs-min3-vec3-vec3-vec3: skip
 spec/amd_shader_trinary_minmax/execution/built-in-functions/tcs-min3-vec4-vec4-vec4: skip
-spec/amd_texture_texture4/execution/texture4: skip
 spec/arb_arrays_of_arrays/execution/image_store/basic-imagestore-const-uniform-index: skip
 spec/arb_arrays_of_arrays/execution/image_store/basic-imagestore-mixed-const-non-const-uniform-index: skip
 spec/arb_arrays_of_arrays/execution/image_store/basic-imagestore-mixed-const-non-const-uniform-index2: skip
@@ -5755,7 +5754,6 @@ spec/arb_tessellation_shader/linker/no-vs: skip
 spec/arb_tessellation_shader/linker/tcs-no-vs: skip
 spec/arb_tessellation_shader/linker/tcs-output-size-declared-in-other-shader: skip
 spec/arb_tessellation_shader/linker/tes-no-vs: skip
-spec/arb_texture_gather/execution/miplevels: skip
 spec/arb_texture_query_lod/execution/fs-texturequerylod-linear: crash
 spec/arb_texture_query_lod/execution/fs-texturequerylod-nearest: crash
 spec/arb_texture_query_lod/execution/fs-texturequerylod-nearest-biased: crash
@@ -13046,7 +13044,7 @@ summary:
        pass:     7204
        fail:       58
       crash:       27
-       skip:    12932
+       skip:    12930
     timeout:        0
        warn:       25
  incomplete:        0
@@ -13055,4 +13053,4 @@ summary:
     changes:        0
       fixes:        0
 regressions:        0
-      total:    20246
+      total:    20244

src/gallium/drivers/d3d12/ci/gitlab-ci.yml

@@ -38,3 +38,5 @@ test-d3d12-quick_shader:
   variables:
     PIGLIT_PROFILE: quick_shader
     PIGLIT_RESULTS: "d3d12-quick_shader"
+    # These tests crash WARP causing the test suite to timeout
+    PIGLIT_TESTS: -x amd_texture_texture4 -x arb_texture_gather

src/gallium/drivers/d3d12/d3d12_screen.cpp

@@ -209,10 +209,8 @@ d3d12_get_param(struct pipe_screen *pscreen, enum pipe_cap param)
    case PIPE_CAP_MIXED_FRAMEBUFFER_SIZES:
       return 1;
 
-#if 0 /* TODO: Enable me. Enables ARB_texture_gather */
    case PIPE_CAP_MAX_TEXTURE_GATHER_COMPONENTS:
       return 4;
-#endif
 
    case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
    case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:

src/microsoft/compiler/dxil_function.c

@@ -59,6 +59,7 @@ static struct  predefined_func_descr predefined_funcs[] = {
 {"dx.op.sampleCmp", "R", "i@@ffffiiiff", DXIL_ATTR_KIND_READ_ONLY},
 {"dx.op.sampleCmpLevelZero", "R", "i@@ffffiiif", DXIL_ATTR_KIND_READ_ONLY},
 {"dx.op.textureLoad", "R", "i@iiiiiii", DXIL_ATTR_KIND_READ_ONLY},
+{"dx.op.textureGather", "R", "i@@ffffiii", DXIL_ATTR_KIND_READ_ONLY},
 {"dx.op.discard", "v", "ib", DXIL_ATTR_KIND_READ_NONE},
 {"dx.op.sampleIndex", "i", "i", DXIL_ATTR_KIND_READ_NONE},
 {"dx.op.emitStream", "v", "ic", DXIL_ATTR_KIND_NONE},

src/microsoft/compiler/nir_to_dxil.c

@@ -235,6 +235,7 @@ enum dxil_intr {
    DXIL_INTR_BUFFER_STORE = 69,
 
    DXIL_INTR_TEXTURE_SIZE = 72,
+   DXIL_INTR_TEXTURE_GATHER = 73,
 
    DXIL_INTR_ATOMIC_BINOP = 78,
    DXIL_INTR_ATOMIC_CMPXCHG = 79,
@@ -3872,6 +3873,29 @@ emit_texture_lod(struct ntd_context *ctx, struct texop_parameters *params)
    return dxil_emit_call(&ctx->mod, func, args, ARRAY_SIZE(args));
 }
 
+static const struct dxil_value *
+emit_texture_gather(struct ntd_context *ctx, struct texop_parameters *params, unsigned component)
+{
+   const struct dxil_func *func = dxil_get_function(&ctx->mod, "dx.op.textureGather", params->overload);
+   if (!func)
+      return false;
+
+   const struct dxil_value *args[] = {
+      dxil_module_get_int32_const(&ctx->mod, DXIL_INTR_TEXTURE_GATHER),
+      params->tex,
+      params->sampler,
+      params->coord[0],
+      params->coord[1],
+      params->coord[2],
+      params->coord[3],
+      params->offset[0],
+      params->offset[1],
+      dxil_module_get_int32_const(&ctx->mod, component)
+   };
+
+   return dxil_emit_call(&ctx->mod, func, args, ARRAY_SIZE(args));
+}
+
 static bool
 emit_tex(struct ntd_context *ctx, nir_tex_instr *instr)
 {
@@ -4031,6 +4055,10 @@ emit_tex(struct ntd_context *ctx, nir_tex_instr *instr)
       sample = emit_texture_size(ctx, &params);
       break;
 
+   case nir_texop_tg4:
+      sample = emit_texture_gather(ctx, &params, instr->component);
+      break;
+
    case nir_texop_lod:
       sample = emit_texture_lod(ctx, &params);
       store_dest(ctx, &instr->dest, 0, sample, nir_alu_type_get_base_type(instr->dest_type));