freedreno/ir3: sample-shading support

The compiler support for:

  OES_sample_shading
  OES_sample_variables
  OES_shader_multisample_interpolation

Signed-off-by: Rob Clark <robdclark@chromium.org>

diff --git a/src/freedreno/ir3/ir3.h b/src/freedreno/ir3/ir3.h
index 5b3544c..f3c25ea 100644 (file)
--- a/src/freedreno/ir3/ir3.h
+++ b/src/freedreno/ir3/ir3.h
@@ -1311,6 +1311,9 @@ INSTR1(SQRT)
 /* cat5 instructions: */
 INSTR1(DSX)
 INSTR1(DSY)
+INSTR1F(3D, DSX)
+INSTR1F(3D, DSY)
+INSTR1(RGETPOS)
 
 static inline struct ir3_instruction *
 ir3_SAM(struct ir3_block *block, opc_t opc, type_t type,

diff --git a/src/freedreno/ir3/ir3_compiler_nir.c b/src/freedreno/ir3/ir3_compiler_nir.c
index 73e7dd6..34fb7b0 100644 (file)
--- a/src/freedreno/ir3/ir3_compiler_nir.c
+++ b/src/freedreno/ir3/ir3_compiler_nir.c
@@ -1127,6 +1127,55 @@ static void add_sysval_input(struct ir3_context *ctx, gl_system_value slot,
        add_sysval_input_compmask(ctx, slot, 0x1, instr);
 }
 
+static struct ir3_instruction *
+get_barycentric_centroid(struct ir3_context *ctx)
+{
+       if (!ctx->ij_centroid) {
+               struct ir3_instruction *xy[2];
+               struct ir3_instruction *ij;
+
+               ij = create_input_compmask(ctx, 0, 0x3);
+               ir3_split_dest(ctx->block, xy, ij, 0, 2);
+
+               ctx->ij_centroid = ir3_create_collect(ctx, xy, 2);
+
+               add_sysval_input_compmask(ctx,
+                               SYSTEM_VALUE_BARYCENTRIC_CENTROID,
+                               0x3, ij);
+       }
+
+       return ctx->ij_centroid;
+}
+
+static struct ir3_instruction *
+get_barycentric_sample(struct ir3_context *ctx)
+{
+       if (!ctx->ij_sample) {
+               struct ir3_instruction *xy[2];
+               struct ir3_instruction *ij;
+
+               ij = create_input_compmask(ctx, 0, 0x3);
+               ir3_split_dest(ctx->block, xy, ij, 0, 2);
+
+               ctx->ij_sample = ir3_create_collect(ctx, xy, 2);
+
+               add_sysval_input_compmask(ctx,
+                               SYSTEM_VALUE_BARYCENTRIC_SAMPLE,
+                               0x3, ij);
+       }
+
+       return ctx->ij_sample;
+}
+
+static struct ir3_instruction  *
+get_barycentric_pixel(struct ir3_context *ctx)
+{
+       /* TODO when tgsi_to_nir supports "new-style" FS inputs switch
+        * this to create ij_pixel only on demand:
+        */
+       return ctx->ij_pixel;
+}
+
 static void
 emit_intrinsic(struct ir3_context *ctx, nir_intrinsic_instr *intr)
 {
@@ -1168,13 +1217,40 @@ emit_intrinsic(struct ir3_context *ctx, nir_intrinsic_instr *intr)
        case nir_intrinsic_load_ubo:
                emit_intrinsic_load_ubo(ctx, intr, dst);
                break;
+       case nir_intrinsic_load_sample_pos_from_id: {
+               /* NOTE: blob seems to always use TYPE_F16 and then cov.f16f32,
+                * but that doesn't seem necessary.
+                */
+               struct ir3_instruction *offset =
+                       ir3_RGETPOS(b, ir3_get_src(ctx, &intr->src[0])[0], 0);
+               offset->regs[0]->wrmask = 0x3;
+               offset->cat5.type = TYPE_F32;
+
+               ir3_split_dest(b, dst, offset, 0, 2);
+
+               break;
+       }
+       case nir_intrinsic_load_size_ir3:
+               if (!ctx->ij_size) {
+                       ctx->ij_size = create_input(ctx, 0);
+
+                       add_sysval_input(ctx, SYSTEM_VALUE_BARYCENTRIC_SIZE,
+                                       ctx->ij_size);
+               }
+               dst[0] = ctx->ij_size;
+               break;
        case nir_intrinsic_load_barycentric_centroid:
+               ir3_split_dest(b, dst, get_barycentric_centroid(ctx), 0, 2);
+               break;
+       case nir_intrinsic_load_barycentric_sample:
+               if (ctx->so->key.msaa) {
+                       ir3_split_dest(b, dst, get_barycentric_sample(ctx), 0, 2);
+               } else {
+                       ir3_split_dest(b, dst, get_barycentric_pixel(ctx), 0, 2);
+               }
+               break;
        case nir_intrinsic_load_barycentric_pixel:
-               /* NOTE: we still pre-create ij_pixel just to keep things working with
-                * nir producers that create "old style" frag shader inputs (ie. just
-                * load_input, vs load_barycentric_* + load_interpolated_input)
-                */
-               ir3_split_dest(b, dst, ctx->ij_pixel, 0, 2);
+               ir3_split_dest(b, dst, get_barycentric_pixel(ctx), 0, 2);
                break;
        case nir_intrinsic_load_interpolated_input:
                idx = nir_intrinsic_base(intr);
@@ -1345,6 +1421,8 @@ emit_intrinsic(struct ir3_context *ctx, nir_intrinsic_instr *intr)
                dst[0] = ctx->instance_id;
                break;
        case nir_intrinsic_load_sample_id:
+               ctx->so->per_samp = true;
+               /* fall-thru */
        case nir_intrinsic_load_sample_id_no_per_sample:
                if (!ctx->samp_id) {
                        ctx->samp_id = create_input(ctx, 0);
@@ -2282,6 +2360,12 @@ setup_input(struct ir3_context *ctx, nir_variable *in)
        so->inputs[n].interpolate = in->data.interpolation;
 
        if (ctx->so->type == MESA_SHADER_FRAGMENT) {
+
+               /* if any varyings have 'sample' qualifer, that triggers us
+                * to run in per-sample mode:
+                */
+               so->per_samp |= in->data.sample;
+
                for (int i = 0; i < ncomp; i++) {
                        struct ir3_instruction *instr = NULL;
                        unsigned idx = (n * 4) + i + frac;
@@ -2457,6 +2541,9 @@ setup_output(struct ir3_context *ctx, nir_variable *out)
                case FRAG_RESULT_COLOR:
                        so->color0_mrt = 1;
                        break;
+               case FRAG_RESULT_SAMPLE_MASK:
+                       so->writes_smask = true;
+                       break;
                default:
                        if (slot >= FRAG_RESULT_DATA0)
                                break;

diff --git a/src/freedreno/ir3/ir3_context.h b/src/freedreno/ir3/ir3_context.h
index 8c1dc45..c3e16ba 100644 (file)
--- a/src/freedreno/ir3/ir3_context.h
+++ b/src/freedreno/ir3/ir3_context.h
@@ -65,7 +65,7 @@ struct ir3_context {
         * inputs.  So we do all the input tracking normally and fix
         * things up after compile_instructions()
         */
-       struct ir3_instruction *ij_pixel;
+       struct ir3_instruction *ij_pixel, *ij_sample, *ij_centroid, *ij_size;
 
        /* for fragment shaders, for gl_FrontFacing and gl_FragCoord: */
        struct ir3_instruction *frag_face, *frag_coord;

diff --git a/src/freedreno/ir3/ir3_shader.c b/src/freedreno/ir3/ir3_shader.c
index fa4f432..3f8e8ab 100644 (file)
--- a/src/freedreno/ir3/ir3_shader.c
+++ b/src/freedreno/ir3/ir3_shader.c
@@ -262,8 +262,15 @@ ir3_shader_from_nir(struct ir3_compiler *compiler, nir_shader *nir)
        NIR_PASS_V(nir, nir_lower_io, nir_var_all, ir3_glsl_type_size,
                           (nir_lower_io_options)0);
 
-       if (nir->info.stage == MESA_SHADER_FRAGMENT)
+       if (nir->info.stage == MESA_SHADER_FRAGMENT) {
+               /* NOTE: lower load_barycentric_at_sample first, since it
+                * produces load_barycentric_at_offset:
+                */
+               NIR_PASS_V(nir, ir3_nir_lower_load_barycentric_at_sample);
+               NIR_PASS_V(nir, ir3_nir_lower_load_barycentric_at_offset);
+
                NIR_PASS_V(nir, ir3_nir_move_varying_inputs);
+       }
 
        NIR_PASS_V(nir, nir_lower_io_arrays_to_elements_no_indirects, false);
 
@@ -409,6 +416,10 @@ ir3_shader_disasm(struct ir3_shader_variant *so, uint32_t *bin, FILE *out)
        case MESA_SHADER_FRAGMENT:
                dump_reg(out, "pos (ij_pixel)",
                        ir3_find_sysval_regid(so, SYSTEM_VALUE_BARYCENTRIC_PIXEL));
+               dump_reg(out, "pos (ij_centroid)",
+                       ir3_find_sysval_regid(so, SYSTEM_VALUE_BARYCENTRIC_CENTROID));
+               dump_reg(out, "pos (ij_size)",
+                       ir3_find_sysval_regid(so, SYSTEM_VALUE_BARYCENTRIC_SIZE));
                dump_output(out, so, FRAG_RESULT_DEPTH, "posz");
                if (so->color0_mrt) {
                        dump_output(out, so, FRAG_RESULT_COLOR, "color");

diff --git a/src/freedreno/ir3/ir3_shader.h b/src/freedreno/ir3/ir3_shader.h
index b3481c1..7f09ee5 100644 (file)
--- a/src/freedreno/ir3/ir3_shader.h
+++ b/src/freedreno/ir3/ir3_shader.h
@@ -154,6 +154,8 @@ struct ir3_shader_key {
                        /*
                         * Fragment shader variant parameters:
                         */
+                       unsigned sample_shading : 1;
+                       unsigned msaa           : 1;
                        unsigned color_two_side : 1;
                        unsigned half_precision : 1;
                        /* used when shader needs to handle flat varyings (a4xx)
@@ -389,7 +391,7 @@ struct ir3_shader_variant {
                uint8_t slot;
                uint8_t regid;
        } outputs[16 + 2];  /* +POSITION +PSIZE */
-       bool writes_pos, writes_psize;
+       bool writes_pos, writes_smask, writes_psize;
 
        /* attributes (VS) / varyings (FS):
         * Note that sysval's should come *after* normal inputs.
@@ -439,6 +441,8 @@ struct ir3_shader_variant {
        /* do we have kill, image write, etc (which prevents early-z): */
        bool no_earlyz;
 
+       bool per_samp;
+
        /* Layout of constant registers, each section (in vec4). Pointer size
         * is 32b (a3xx, a4xx), or 64b (a5xx+), which effects the size of the
         * UBO and stream-out consts.