nir: add mediump flag to IO semantics

Reviewed-by: Alyssa Rosenzweig <alyssa.rosenzweig@collabora.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/6621>

diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 30c298c..22d6e6c 100644 (file)
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -1784,7 +1784,8 @@ typedef struct {
    unsigned dual_source_blend_index:1;
    unsigned fb_fetch_output:1; /* for GL_KHR_blend_equation_advanced */
    unsigned gs_streams:8; /* xxyyzzww: 2-bit stream index for each component */
-   unsigned _pad:9;
+   unsigned medium_precision:1; /* GLSL mediump qualifier */
+   unsigned _pad:8;
 } nir_io_semantics;
 
 #define NIR_INTRINSIC_MAX_INPUTS 5

diff --git a/src/compiler/nir/nir_lower_io.c b/src/compiler/nir/nir_lower_io.c
index fbe8e51..52c22ad 100644 (file)
--- a/src/compiler/nir/nir_lower_io.c
+++ b/src/compiler/nir/nir_lower_io.c
@@ -309,6 +309,9 @@ emit_load(struct lower_io_state *state,
       semantics.location = var->data.location;
       semantics.num_slots = get_number_of_slots(state, var);
       semantics.fb_fetch_output = var->data.fb_fetch_output;
+      semantics.medium_precision =
+         var->data.precision == GLSL_PRECISION_MEDIUM ||
+         var->data.precision == GLSL_PRECISION_LOW;
       nir_intrinsic_set_io_semantics(load, semantics);
    }
 
@@ -431,6 +434,9 @@ emit_store(struct lower_io_state *state, nir_ssa_def *data,
    semantics.num_slots = get_number_of_slots(state, var);
    semantics.dual_source_blend_index = var->data.index;
    semantics.gs_streams = gs_streams;
+   semantics.medium_precision =
+      var->data.precision == GLSL_PRECISION_MEDIUM ||
+      var->data.precision == GLSL_PRECISION_LOW;
    nir_intrinsic_set_io_semantics(store, semantics);
 
    nir_builder_instr_insert(b, &store->instr);
@@ -562,6 +568,9 @@ lower_interpolate_at(nir_intrinsic_instr *intrin, struct lower_io_state *state,
    nir_io_semantics semantics = {0};
    semantics.location = var->data.location;
    semantics.num_slots = get_number_of_slots(state, var);
+   semantics.medium_precision =
+      var->data.precision == GLSL_PRECISION_MEDIUM ||
+      var->data.precision == GLSL_PRECISION_LOW;
    nir_intrinsic_set_io_semantics(load, semantics);
 
    load->src[0] = nir_src_for_ssa(&bary_setup->dest.ssa);

diff --git a/src/compiler/nir/nir_print.c b/src/compiler/nir/nir_print.c
index 810d3ce..bfc35d9 100644 (file)
--- a/src/compiler/nir/nir_print.c
+++ b/src/compiler/nir/nir_print.c
@@ -982,6 +982,10 @@ print_intrinsic_instr(nir_intrinsic_instr *instr, print_state *state)
                }
                fprintf(fp, ")");
             }
+            if (state->shader->info.stage == MESA_SHADER_FRAGMENT &&
+                nir_intrinsic_io_semantics(instr).medium_precision) {
+               fprintf(fp, " mediump");
+            }
          }
          break;