freedreno/ir3: Implement TCS synchronization intrinsics

We add two new IR3 specific nir intrinsics that map to the new condend
and endpatch instructions.

Signed-off-by: Kristian H. Kristensen <[email protected]>
Acked-by: Eric Anholt <[email protected]>
Reviewed-by: Rob Clark <[email protected]>

2 files changed, 41 insertions, 0 deletions

diff --git a/src/compiler/nir/nir_intrinsics.py b/src/compiler/nir/nir_intrinsics.py
index 55050a9e058..4658187ea16 100644
--- a/src/compiler/nir/nir_intrinsics.py
+++ b/src/compiler/nir/nir_intrinsics.py
@@ -798,6 +798,14 @@ system_value("tess_factor_base_ir3", 2)
 system_value("tess_param_base_ir3", 2)
 system_value("tcs_header_ir3", 1)
 
+# IR3-specific intrinsics for tessellation control shaders.  cond_end_ir3 end
+# the shader when src0 is false and is used to narrow down the TCS shader to
+# just thread 0 before writing out tessellation levels.
+intrinsic("cond_end_ir3", src_comp=[1])
+# end_patch_ir3 is used just before thread 0 exist the TCS and presumably
+# signals the TE that the patch is complete and can be tessellated.
+intrinsic("end_patch_ir3")
+
 # IR3-specific load/store intrinsics. These access a buffer used to pass data
 # between geometry stages - perhaps it's explicit access to the vertex cache.
 
diff --git a/src/freedreno/ir3/ir3_compiler_nir.c b/src/freedreno/ir3/ir3_compiler_nir.c
index b2068a35466..2341c359324 100644
--- a/src/freedreno/ir3/ir3_compiler_nir.c
+++ b/src/freedreno/ir3/ir3_compiler_nir.c
@@ -1406,6 +1406,15 @@ emit_intrinsic(struct ir3_context *ctx, nir_intrinsic_instr *intr)
 		dst[2] = create_immed(b, 0);
 		break;
 
+	case nir_intrinsic_end_patch_ir3:
+		assert(ctx->so->type == MESA_SHADER_TESS_CTRL);
+		struct ir3_instruction *end = ir3_ENDPATCH(b);
+		array_insert(b, b->keeps, end);
+
+		end->barrier_class = IR3_BARRIER_EVERYTHING;
+		end->barrier_conflict = IR3_BARRIER_EVERYTHING;
+		break;
+
 	case nir_intrinsic_store_global_ir3: {
 		struct ir3_instruction *value, *addr, *offset;
 
@@ -1762,6 +1771,30 @@ emit_intrinsic(struct ir3_context *ctx, nir_intrinsic_instr *intr)
 
 		break;
 	}
+
+	case nir_intrinsic_cond_end_ir3: {
+		struct ir3_instruction *cond, *kill;
+
+		src = ir3_get_src(ctx, &intr->src[0]);
+		cond = ir3_b2n(b, src[0]);
+
+		/* NOTE: only cmps.*.* can write p0.x: */
+		cond = ir3_CMPS_S(b, cond, 0, create_immed(b, 0), 0);
+		cond->cat2.condition = IR3_COND_NE;
+
+		/* condition always goes in predicate register: */
+		cond->regs[0]->num = regid(REG_P0, 0);
+
+		kill = ir3_CONDEND(b, cond, 0);
+
+		kill->barrier_class = IR3_BARRIER_EVERYTHING;
+		kill->barrier_conflict = IR3_BARRIER_EVERYTHING;
+
+		array_insert(ctx->ir, ctx->ir->predicates, kill);
+		array_insert(b, b->keeps, kill);
+		break;
+	}
+
 	case nir_intrinsic_load_shared_ir3:
 		emit_intrinsic_load_shared_ir3(ctx, intr, dst);
 		break;