pan/bi: Implement store_output for fragment shaders

Corresponds to a BLEND instruction, possibly preceded by an ATEST
instruction.

Signed-off-by: Alyssa Rosenzweig <[email protected]>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/4097>

1 files changed, 32 insertions, 0 deletions

diff --git a/src/panfrost/bifrost/bifrost_compile.c b/src/panfrost/bifrost/bifrost_compile.c
index 6a57adc4e53..922591279c5 100644
--- a/src/panfrost/bifrost/bifrost_compile.c
+++ b/src/panfrost/bifrost/bifrost_compile.c
@@ -89,6 +89,31 @@ bi_emit_ld_vary(bi_context *ctx, nir_intrinsic_instr *instr)
 }
 
 static void
+bi_emit_frag_out(bi_context *ctx, nir_intrinsic_instr *instr)
+{
+        if (!ctx->emitted_atest) {
+                bi_instruction ins = {
+                        .type = BI_ATEST
+                };
+
+                bi_emit(ctx, ins);
+                bi_schedule_barrier(ctx);
+                ctx->emitted_atest = true;
+        }
+
+        bi_instruction blend = {
+                .type = BI_BLEND,
+                .blend_location = nir_intrinsic_base(instr),
+                .src = {
+                        bir_src_index(&instr->src[0])
+                }
+        };
+
+        bi_emit(ctx, blend);
+        bi_schedule_barrier(ctx);
+}
+
+static void
 emit_intrinsic(bi_context *ctx, nir_intrinsic_instr *instr)
 {
 
@@ -99,6 +124,13 @@ emit_intrinsic(bi_context *ctx, nir_intrinsic_instr *instr)
         case nir_intrinsic_load_interpolated_input:
                 bi_emit_ld_vary(ctx, instr);
                 break;
+        case nir_intrinsic_store_output:
+                if (ctx->stage == MESA_SHADER_FRAGMENT)
+                        bi_emit_frag_out(ctx, instr);
+                else {
+                        /* TODO */
+                }
+                break;
         default:
                 /* todo */
                 break;