radv/gfx10: implement NGG streamout
authorSamuel Pitoiset <samuel.pitoiset@gmail.com>
Mon, 9 Sep 2019 08:54:27 +0000 (10:54 +0200)
committerSamuel Pitoiset <samuel.pitoiset@gmail.com>
Mon, 16 Sep 2019 10:08:22 +0000 (12:08 +0200)
It's still disabled by default because transform feedback randomly
hangs and it seems like it's related to GDS (cf. RadeonSI).

Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <bas@basnieuwenhuizen.nl>
src/amd/vulkan/radv_nir_to_llvm.c

index 4454502cc31cc3f0c77948d848c22c78da575308..ee4acf7b5a787d5cbe18b676d02ac8197dc0dded 100644 (file)
@@ -2980,6 +2980,14 @@ static LLVMValueRef ngg_get_prim_cnt(struct radv_shader_context *ctx)
                            false);
 }
 
+static LLVMValueRef ngg_get_ordered_id(struct radv_shader_context *ctx)
+{
+       return ac_build_bfe(&ctx->ac, ctx->gs_tg_info,
+                           ctx->ac.i32_0,
+                           LLVMConstInt(ctx->ac.i32, 11, false),
+                           false);
+}
+
 static LLVMValueRef
 ngg_gs_get_vertex_storage(struct radv_shader_context *ctx)
 {
@@ -3125,8 +3133,436 @@ static void build_export_prim(struct radv_shader_context *ctx,
        ac_build_export(&ctx->ac, &args);
 }
 
+static void build_streamout_vertex(struct radv_shader_context *ctx,
+                                  LLVMValueRef *so_buffer, LLVMValueRef *wg_offset_dw,
+                                  unsigned stream, LLVMValueRef offset_vtx,
+                                  LLVMValueRef vertexptr)
+{
+       struct radv_streamout_info *so = &ctx->shader_info->so;
+       LLVMBuilderRef builder = ctx->ac.builder;
+       LLVMValueRef offset[4] = {};
+       LLVMValueRef tmp;
+
+       for (unsigned buffer = 0; buffer < 4; ++buffer) {
+               if (!wg_offset_dw[buffer])
+                       continue;
+
+               tmp = LLVMBuildMul(builder, offset_vtx,
+                                  LLVMConstInt(ctx->ac.i32, so->strides[buffer], false), "");
+               tmp = LLVMBuildAdd(builder, wg_offset_dw[buffer], tmp, "");
+               offset[buffer] = LLVMBuildShl(builder, tmp, LLVMConstInt(ctx->ac.i32, 2, false), "");
+       }
+
+       for (unsigned i = 0; i < so->num_outputs; ++i) {
+               struct radv_stream_output *output =
+                       &ctx->shader_info->so.outputs[i];
+
+               if (stream != output->stream)
+                       continue;
+
+               unsigned loc = output->location;
+               struct radv_shader_output_values out = {};
+
+               for (unsigned comp = 0; comp < 4; comp++) {
+                       tmp = ac_build_gep0(&ctx->ac, vertexptr,
+                                           LLVMConstInt(ctx->ac.i32, 4 * loc + comp, false));
+                       out.values[comp] = LLVMBuildLoad(builder, tmp, "");
+               }
+
+               radv_emit_stream_output(ctx, so_buffer, offset, output, &out);
+       }
+}
+
+struct ngg_streamout {
+       LLVMValueRef num_vertices;
+
+       /* per-thread data */
+       LLVMValueRef prim_enable[4]; /* i1 per stream */
+       LLVMValueRef vertices[3]; /* [N x i32] addrspace(LDS)* */
+
+       /* Output */
+       LLVMValueRef emit[4]; /* per-stream emitted primitives (only valid for used streams) */
+};
+
+/**
+ * Build streamout logic.
+ *
+ * Implies a barrier.
+ *
+ * Writes number of emitted primitives to gs_ngg_scratch[4:7].
+ *
+ * Clobbers gs_ngg_scratch[8:].
+ */
+static void build_streamout(struct radv_shader_context *ctx,
+                           struct ngg_streamout *nggso)
+{
+       struct radv_streamout_info *so = &ctx->shader_info->so;
+       LLVMBuilderRef builder = ctx->ac.builder;
+       LLVMValueRef buf_ptr = ctx->streamout_buffers;
+       LLVMValueRef tid = get_thread_id_in_tg(ctx);
+       LLVMValueRef cond, tmp, tmp2;
+       LLVMValueRef i32_2 = LLVMConstInt(ctx->ac.i32, 2, false);
+       LLVMValueRef i32_4 = LLVMConstInt(ctx->ac.i32, 4, false);
+       LLVMValueRef i32_8 = LLVMConstInt(ctx->ac.i32, 8, false);
+       LLVMValueRef so_buffer[4] = {};
+       unsigned max_num_vertices = 1 + (nggso->vertices[1] ? 1 : 0) +
+                                       (nggso->vertices[2] ? 1 : 0);
+       LLVMValueRef prim_stride_dw[4] = {};
+       LLVMValueRef prim_stride_dw_vgpr = LLVMGetUndef(ctx->ac.i32);
+       int stream_for_buffer[4] = { -1, -1, -1, -1 };
+       unsigned bufmask_for_stream[4] = {};
+       bool isgs = ctx->stage == MESA_SHADER_GEOMETRY;
+       unsigned scratch_emit_base = isgs ? 4 : 0;
+       LLVMValueRef scratch_emit_basev = isgs ? i32_4 : ctx->ac.i32_0;
+       unsigned scratch_offset_base = isgs ? 8 : 4;
+       LLVMValueRef scratch_offset_basev = isgs ? i32_8 : i32_4;
+
+       ac_llvm_add_target_dep_function_attr(ctx->main_function,
+                                            "amdgpu-gds-size", 256);
+
+       /* Determine the mapping of streamout buffers to vertex streams. */
+       for (unsigned i = 0; i < so->num_outputs; ++i) {
+               unsigned buf = so->outputs[i].buffer;
+               unsigned stream = so->outputs[i].stream;
+               assert(stream_for_buffer[buf] < 0 || stream_for_buffer[buf] == stream);
+               stream_for_buffer[buf] = stream;
+               bufmask_for_stream[stream] |= 1 << buf;
+       }
+
+       for (unsigned buffer = 0; buffer < 4; ++buffer) {
+               if (stream_for_buffer[buffer] == -1)
+                       continue;
+
+               assert(so->strides[buffer]);
+
+               LLVMValueRef stride_for_buffer =
+                       LLVMConstInt(ctx->ac.i32, so->strides[buffer], false);
+               prim_stride_dw[buffer] =
+                       LLVMBuildMul(builder, stride_for_buffer,
+                                    nggso->num_vertices, "");
+               prim_stride_dw_vgpr = ac_build_writelane(
+                       &ctx->ac, prim_stride_dw_vgpr, prim_stride_dw[buffer],
+                       LLVMConstInt(ctx->ac.i32, buffer, false));
+
+               LLVMValueRef offset = LLVMConstInt(ctx->ac.i32, buffer, false);
+               so_buffer[buffer] = ac_build_load_to_sgpr(&ctx->ac, buf_ptr,
+                                                         offset);
+       }
+
+       cond = LLVMBuildICmp(builder, LLVMIntEQ, get_wave_id_in_tg(ctx), ctx->ac.i32_0, "");
+       ac_build_ifcc(&ctx->ac, cond, 5200);
+       {
+               LLVMTypeRef gdsptr = LLVMPointerType(ctx->ac.i32, AC_ADDR_SPACE_GDS);
+               LLVMValueRef gdsbase = LLVMBuildIntToPtr(builder, ctx->ac.i32_0, gdsptr, "");
+
+               /* Advance the streamout offsets in GDS. */
+               LLVMValueRef offsets_vgpr = ac_build_alloca_undef(&ctx->ac, ctx->ac.i32, "");
+               LLVMValueRef generated_by_stream_vgpr = ac_build_alloca_undef(&ctx->ac, ctx->ac.i32, "");
+
+               cond = LLVMBuildICmp(builder, LLVMIntULT, ac_get_thread_id(&ctx->ac), i32_4, "");
+               ac_build_ifcc(&ctx->ac, cond, 5210);
+               {
+                       /* Fetch the number of generated primitives and store
+                        * it in GDS for later use.
+                        */
+                       if (isgs) {
+                               tmp = ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch, tid);
+                               tmp = LLVMBuildLoad(builder, tmp, "");
+                       } else {
+                               tmp = ac_build_writelane(&ctx->ac, ctx->ac.i32_0,
+                                               ngg_get_prim_cnt(ctx), ctx->ac.i32_0);
+                       }
+                       LLVMBuildStore(builder, tmp, generated_by_stream_vgpr);
+
+                       unsigned swizzle[4];
+                       int unused_stream = -1;
+                       for (unsigned stream = 0; stream < 4; ++stream) {
+                               if (!ctx->shader_info->gs.num_stream_output_components[stream]) {
+                                       unused_stream = stream;
+                                       break;
+                               }
+                       }
+                       for (unsigned buffer = 0; buffer < 4; ++buffer) {
+                               if (stream_for_buffer[buffer] >= 0) {
+                                       swizzle[buffer] = stream_for_buffer[buffer];
+                               } else {
+                                       assert(unused_stream >= 0);
+                                       swizzle[buffer] = unused_stream;
+                               }
+                       }
+
+                       tmp = ac_build_quad_swizzle(&ctx->ac, tmp,
+                               swizzle[0], swizzle[1], swizzle[2], swizzle[3]);
+                       tmp = LLVMBuildMul(builder, tmp, prim_stride_dw_vgpr, "");
+
+                       LLVMValueRef args[] = {
+                               LLVMBuildIntToPtr(builder, ngg_get_ordered_id(ctx), gdsptr, ""),
+                               tmp,
+                               ctx->ac.i32_0, // ordering
+                               ctx->ac.i32_0, // scope
+                               ctx->ac.i1false, // isVolatile
+                               LLVMConstInt(ctx->ac.i32, 4 << 24, false), // OA index
+                               ctx->ac.i1true, // wave release
+                               ctx->ac.i1true, // wave done
+                       };
+
+                       tmp = ac_build_intrinsic(&ctx->ac, "llvm.amdgcn.ds.ordered.add",
+                                                ctx->ac.i32, args, ARRAY_SIZE(args), 0);
+
+                       /* Keep offsets in a VGPR for quick retrieval via readlane by
+                        * the first wave for bounds checking, and also store in LDS
+                        * for retrieval by all waves later. */
+                       LLVMBuildStore(builder, tmp, offsets_vgpr);
+
+                       tmp2 = LLVMBuildAdd(builder, ac_get_thread_id(&ctx->ac),
+                                           scratch_offset_basev, "");
+                       tmp2 = ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch, tmp2);
+                       LLVMBuildStore(builder, tmp, tmp2);
+               }
+               ac_build_endif(&ctx->ac, 5210);
+
+               /* Determine the max emit per buffer. This is done via the SALU, in part
+                * because LLVM can't generate divide-by-multiply if we try to do this
+                * via VALU with one lane per buffer.
+                */
+               LLVMValueRef max_emit[4] = {};
+               for (unsigned buffer = 0; buffer < 4; ++buffer) {
+                       if (stream_for_buffer[buffer] == -1)
+                               continue;
+
+                       /* Compute the streamout buffer size in DWORD. */
+                       LLVMValueRef bufsize_dw =
+                               LLVMBuildLShr(builder,
+                                       LLVMBuildExtractElement(builder, so_buffer[buffer], i32_2, ""),
+                                       i32_2, "");
+
+                       /* Load the streamout buffer offset from GDS. */
+                       tmp = LLVMBuildLoad(builder, offsets_vgpr, "");
+                       LLVMValueRef offset_dw =
+                               ac_build_readlane(&ctx->ac, tmp,
+                                               LLVMConstInt(ctx->ac.i32, buffer, false));
+
+                       /* Compute the remaining size to emit. */
+                       LLVMValueRef remaining_dw =
+                               LLVMBuildSub(builder, bufsize_dw, offset_dw, "");
+                       tmp = LLVMBuildUDiv(builder, remaining_dw,
+                                           prim_stride_dw[buffer], "");
+
+                       cond = LLVMBuildICmp(builder, LLVMIntULT,
+                                            bufsize_dw, offset_dw, "");
+                       max_emit[buffer] = LLVMBuildSelect(builder, cond,
+                                                          ctx->ac.i32_0, tmp, "");
+               }
+
+               /* Determine the number of emitted primitives per stream and fixup the
+                * GDS counter if necessary.
+                *
+                * This is complicated by the fact that a single stream can emit to
+                * multiple buffers (but luckily not vice versa).
+                */
+               LLVMValueRef emit_vgpr = ctx->ac.i32_0;
+
+               for (unsigned stream = 0; stream < 4; ++stream) {
+                       if (!ctx->shader_info->gs.num_stream_output_components[stream])
+                               continue;
+
+                       /* Load the number of generated primitives from GDS and
+                        * determine that number for the given stream.
+                        */
+                       tmp = LLVMBuildLoad(builder, generated_by_stream_vgpr, "");
+                       LLVMValueRef generated =
+                               ac_build_readlane(&ctx->ac, tmp,
+                                                 LLVMConstInt(ctx->ac.i32, stream, false));
+
+
+                       /* Compute the number of emitted primitives. */
+                       LLVMValueRef emit = generated;
+                       for (unsigned buffer = 0; buffer < 4; ++buffer) {
+                               if (stream_for_buffer[buffer] == stream)
+                                       emit = ac_build_umin(&ctx->ac, emit, max_emit[buffer]);
+                       }
+
+                       /* Store the number of emitted primitives for that
+                        * stream.
+                        */
+                       emit_vgpr = ac_build_writelane(&ctx->ac, emit_vgpr, emit,
+                                                      LLVMConstInt(ctx->ac.i32, stream, false));
+
+                       /* Fixup the offset using a plain GDS atomic if we overflowed. */
+                       cond = LLVMBuildICmp(builder, LLVMIntULT, emit, generated, "");
+                       ac_build_ifcc(&ctx->ac, cond, 5221); /* scalar branch */
+                       tmp = LLVMBuildLShr(builder,
+                                           LLVMConstInt(ctx->ac.i32, bufmask_for_stream[stream], false),
+                                           ac_get_thread_id(&ctx->ac), "");
+                       tmp = LLVMBuildTrunc(builder, tmp, ctx->ac.i1, "");
+                       ac_build_ifcc(&ctx->ac, tmp, 5222);
+                       {
+                               tmp = LLVMBuildSub(builder, generated, emit, "");
+                               tmp = LLVMBuildMul(builder, tmp, prim_stride_dw_vgpr, "");
+                               tmp2 = LLVMBuildGEP(builder, gdsbase, &tid, 1, "");
+                               LLVMBuildAtomicRMW(builder, LLVMAtomicRMWBinOpSub, tmp2, tmp,
+                                                  LLVMAtomicOrderingMonotonic, false);
+                       }
+                       ac_build_endif(&ctx->ac, 5222);
+                       ac_build_endif(&ctx->ac, 5221);
+               }
+
+               /* Store the number of emitted primitives to LDS for later use. */
+               cond = LLVMBuildICmp(builder, LLVMIntULT, ac_get_thread_id(&ctx->ac), i32_4, "");
+               ac_build_ifcc(&ctx->ac, cond, 5225);
+               {
+                       tmp = LLVMBuildAdd(builder, ac_get_thread_id(&ctx->ac),
+                                          scratch_emit_basev, "");
+                       tmp = ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch, tmp);
+                       LLVMBuildStore(builder, emit_vgpr, tmp);
+               }
+               ac_build_endif(&ctx->ac, 5225);
+       }
+       ac_build_endif(&ctx->ac, 5200);
+
+       /* Determine the workgroup-relative per-thread / primitive offset into
+        * the streamout buffers */
+       struct ac_wg_scan primemit_scan[4] = {};
+
+       if (isgs) {
+               for (unsigned stream = 0; stream < 4; ++stream) {
+                       if (!ctx->shader_info->gs.num_stream_output_components[stream])
+                               continue;
+
+                       primemit_scan[stream].enable_exclusive = true;
+                       primemit_scan[stream].op = nir_op_iadd;
+                       primemit_scan[stream].src = nggso->prim_enable[stream];
+                       primemit_scan[stream].scratch =
+                               ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch,
+                                       LLVMConstInt(ctx->ac.i32, 12 + 8 * stream, false));
+                       primemit_scan[stream].waveidx = get_wave_id_in_tg(ctx);
+                       primemit_scan[stream].numwaves = get_tgsize(ctx);
+                       primemit_scan[stream].maxwaves = 8;
+                       ac_build_wg_scan_top(&ctx->ac, &primemit_scan[stream]);
+               }
+       }
+
+       ac_build_s_barrier(&ctx->ac);
+
+       /* Fetch the per-buffer offsets and per-stream emit counts in all waves. */
+       LLVMValueRef wgoffset_dw[4] = {};
+
+       {
+               LLVMValueRef scratch_vgpr;
+
+               tmp = ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch, ac_get_thread_id(&ctx->ac));
+               scratch_vgpr = LLVMBuildLoad(builder, tmp, "");
+
+               for (unsigned buffer = 0; buffer < 4; ++buffer) {
+                       if (stream_for_buffer[buffer] >= 0) {
+                               wgoffset_dw[buffer] = ac_build_readlane(
+                                       &ctx->ac, scratch_vgpr,
+                                       LLVMConstInt(ctx->ac.i32, scratch_offset_base + buffer, false));
+                       }
+               }
+
+               for (unsigned stream = 0; stream < 4; ++stream) {
+                       if (ctx->shader_info->gs.num_stream_output_components[stream]) {
+                               nggso->emit[stream] = ac_build_readlane(
+                                       &ctx->ac, scratch_vgpr,
+                                       LLVMConstInt(ctx->ac.i32, scratch_emit_base + stream, false));
+                       }
+               }
+       }
+
+       /* Write out primitive data */
+       for (unsigned stream = 0; stream < 4; ++stream) {
+               if (!ctx->shader_info->gs.num_stream_output_components[stream])
+                       continue;
+
+               if (isgs) {
+                       ac_build_wg_scan_bottom(&ctx->ac, &primemit_scan[stream]);
+               } else {
+                       primemit_scan[stream].result_exclusive = tid;
+               }
+
+               cond = LLVMBuildICmp(builder, LLVMIntULT,
+                                   primemit_scan[stream].result_exclusive,
+                                   nggso->emit[stream], "");
+               cond = LLVMBuildAnd(builder, cond, nggso->prim_enable[stream], "");
+               ac_build_ifcc(&ctx->ac, cond, 5240);
+               {
+                       LLVMValueRef offset_vtx =
+                               LLVMBuildMul(builder, primemit_scan[stream].result_exclusive,
+                                            nggso->num_vertices, "");
+
+                       for (unsigned i = 0; i < max_num_vertices; ++i) {
+                               cond = LLVMBuildICmp(builder, LLVMIntULT,
+                                                   LLVMConstInt(ctx->ac.i32, i, false),
+                                                   nggso->num_vertices, "");
+                               ac_build_ifcc(&ctx->ac, cond, 5241);
+                               build_streamout_vertex(ctx, so_buffer, wgoffset_dw,
+                                                      stream, offset_vtx, nggso->vertices[i]);
+                               ac_build_endif(&ctx->ac, 5241);
+                               offset_vtx = LLVMBuildAdd(builder, offset_vtx, ctx->ac.i32_1, "");
+                       }
+               }
+               ac_build_endif(&ctx->ac, 5240);
+       }
+}
+
+static unsigned ngg_nogs_vertex_size(struct radv_shader_context *ctx)
+{
+       unsigned lds_vertex_size = 0;
+
+       if (ctx->shader_info->so.num_outputs)
+               lds_vertex_size = 4 * ctx->shader_info->so.num_outputs + 1;
+
+       return lds_vertex_size;
+}
+
+/**
+ * Returns an `[N x i32] addrspace(LDS)*` pointing at contiguous LDS storage
+ * for the vertex outputs.
+ */
+static LLVMValueRef ngg_nogs_vertex_ptr(struct radv_shader_context *ctx,
+                                       LLVMValueRef vtxid)
+{
+       /* The extra dword is used to avoid LDS bank conflicts. */
+       unsigned vertex_size = ngg_nogs_vertex_size(ctx);
+       LLVMTypeRef ai32 = LLVMArrayType(ctx->ac.i32, vertex_size);
+       LLVMTypeRef pai32 = LLVMPointerType(ai32, AC_ADDR_SPACE_LDS);
+       LLVMValueRef tmp = LLVMBuildBitCast(ctx->ac.builder, ctx->esgs_ring, pai32, "");
+       return LLVMBuildGEP(ctx->ac.builder, tmp, &vtxid, 1, "");
+}
+
+static void
+handle_ngg_outputs_post_1(struct radv_shader_context *ctx)
+{
+       LLVMBuilderRef builder = ctx->ac.builder;
+       LLVMValueRef vertex_ptr = NULL;
+       LLVMValueRef tmp, tmp2;
+
+       assert((ctx->stage == MESA_SHADER_VERTEX ||
+               ctx->stage == MESA_SHADER_TESS_EVAL) && !ctx->is_gs_copy_shader);
+
+       if (!ctx->shader_info->so.num_outputs)
+               return;
+
+       vertex_ptr = ngg_nogs_vertex_ptr(ctx, get_thread_id_in_tg(ctx));
+
+       for (unsigned i = 0; i < AC_LLVM_MAX_OUTPUTS; ++i) {
+               if (!(ctx->output_mask & (1ull << i)))
+                       continue;
+
+               for (unsigned j = 0; j < 4; j++) {
+                       tmp = ac_build_gep0(&ctx->ac, vertex_ptr,
+                                           LLVMConstInt(ctx->ac.i32, 4 * i + j, false));
+                       tmp2 = LLVMBuildLoad(builder,
+                                            ctx->abi.outputs[4 * i + j], "");
+                       tmp2 = ac_to_integer(&ctx->ac, tmp2);
+                       LLVMBuildStore(builder, tmp2, tmp);
+               }
+       }
+}
+
 static void
-handle_ngg_outputs_post(struct radv_shader_context *ctx)
+handle_ngg_outputs_post_2(struct radv_shader_context *ctx)
 {
        LLVMBuilderRef builder = ctx->ac.builder;
        LLVMValueRef tmp;
@@ -3148,8 +3584,10 @@ handle_ngg_outputs_post(struct radv_shader_context *ctx)
 
        /* Determine the number of vertices per primitive. */
        unsigned num_vertices;
+       LLVMValueRef num_vertices_val;
 
        if (ctx->stage == MESA_SHADER_VERTEX) {
+               num_vertices_val = LLVMConstInt(ctx->ac.i32, 1, false);
                num_vertices = 3; /* TODO: optimize for points & lines */
        } else {
                assert(ctx->stage == MESA_SHADER_TESS_EVAL);
@@ -3160,16 +3598,30 @@ handle_ngg_outputs_post(struct radv_shader_context *ctx)
                        num_vertices = 2;
                else
                        num_vertices = 3;
+
+               num_vertices_val = LLVMConstInt(ctx->ac.i32, num_vertices, false);
        }
 
-       /* TODO: streamout */
+       /* Streamout */
+       if (ctx->shader_info->so.num_outputs) {
+               struct ngg_streamout nggso = {};
+
+               nggso.num_vertices = num_vertices_val;
+               nggso.prim_enable[0] = is_gs_thread;
+
+               for (unsigned i = 0; i < num_vertices; ++i)
+                       nggso.vertices[i] = ngg_nogs_vertex_ptr(ctx, vtxindex[i]);
+
+               build_streamout(ctx, &nggso);
+       }
 
        /* Copy Primitive IDs from GS threads to the LDS address corresponding
         * to the ES thread of the provoking vertex.
         */
        if (ctx->stage == MESA_SHADER_VERTEX &&
            ctx->options->key.vs_common_out.export_prim_id) {
-               /* TODO: streamout */
+               if (ctx->shader_info->so.num_outputs)
+                       ac_build_s_barrier(&ctx->ac);
 
                ac_build_ifcc(&ctx->ac, is_gs_thread, 5400);
                /* Extract the PROVOKING_VTX_INDEX field. */
@@ -3341,6 +3793,30 @@ static void gfx10_ngg_gs_emit_epilogue_1(struct radv_shader_context *ctx)
 
                ac_build_endloop(&ctx->ac, 5100);
        }
+
+       /* Accumulate generated primitives counts across the entire threadgroup. */
+       for (unsigned stream = 0; stream < 4; ++stream) {
+               unsigned num_components;
+
+               num_components =
+                       ctx->shader_info->gs.num_stream_output_components[stream];
+               if (!num_components)
+                       continue;
+
+               LLVMValueRef numprims =
+                       LLVMBuildLoad(builder, ctx->gs_generated_prims[stream], "");
+               numprims = ac_build_reduce(&ctx->ac, numprims, nir_op_iadd, ctx->ac.wave_size);
+
+               tmp = LLVMBuildICmp(builder, LLVMIntEQ, ac_get_thread_id(&ctx->ac), ctx->ac.i32_0, "");
+               ac_build_ifcc(&ctx->ac, tmp, 5105);
+               {
+                       LLVMBuildAtomicRMW(builder, LLVMAtomicRMWBinOpAdd,
+                                          ac_build_gep0(&ctx->ac, ctx->gs_ngg_scratch,
+                                                        LLVMConstInt(ctx->ac.i32, stream, false)),
+                                          numprims, LLVMAtomicOrderingMonotonic, false);
+               }
+               ac_build_endif(&ctx->ac, 5105);
+       }
 }
 
 static void gfx10_ngg_gs_emit_epilogue_2(struct radv_shader_context *ctx)
@@ -3354,7 +3830,38 @@ static void gfx10_ngg_gs_emit_epilogue_2(struct radv_shader_context *ctx)
        const LLVMValueRef tid = get_thread_id_in_tg(ctx);
        LLVMValueRef num_emit_threads = ngg_get_prim_cnt(ctx);
 
-       /* TODO: streamout */
+       /* Streamout */
+       if (ctx->shader_info->so.num_outputs) {
+               struct ngg_streamout nggso = {};
+
+               nggso.num_vertices = LLVMConstInt(ctx->ac.i32, verts_per_prim, false);
+
+               LLVMValueRef vertexptr = ngg_gs_vertex_ptr(ctx, tid);
+               for (unsigned stream = 0; stream < 4; ++stream) {
+                       if (!ctx->shader_info->gs.num_stream_output_components[stream])
+                               continue;
+
+                       LLVMValueRef gep_idx[3] = {
+                               ctx->ac.i32_0, /* implicit C-style array */
+                               ctx->ac.i32_1, /* second value of struct */
+                               LLVMConstInt(ctx->ac.i32, stream, false),
+                       };
+                       tmp = LLVMBuildGEP(builder, vertexptr, gep_idx, 3, "");
+                       tmp = LLVMBuildLoad(builder, tmp, "");
+                       tmp = LLVMBuildTrunc(builder, tmp, ctx->ac.i1, "");
+                       tmp2 = LLVMBuildICmp(builder, LLVMIntULT, tid, num_emit_threads, "");
+                       nggso.prim_enable[stream] = LLVMBuildAnd(builder, tmp, tmp2, "");
+               }
+
+               for (unsigned i = 0; i < verts_per_prim; ++i) {
+                       tmp = LLVMBuildSub(builder, tid,
+                                          LLVMConstInt(ctx->ac.i32, verts_per_prim - i - 1, false), "");
+                       tmp = ngg_gs_vertex_ptr(ctx, tmp);
+                       nggso.vertices[i] = ac_build_gep0(&ctx->ac, tmp, ctx->ac.i32_0);
+               }
+
+               build_streamout(ctx, &nggso);
+       }
 
        /* TODO: culling */
 
@@ -3911,7 +4418,7 @@ handle_shader_outputs_post(struct ac_shader_abi *abi, unsigned max_outputs,
                else if (ctx->options->key.vs_common_out.as_es)
                        handle_es_outputs_post(ctx, &ctx->shader_info->vs.es_info);
                else if (ctx->options->key.vs_common_out.as_ngg)
-                       break; /* handled outside of the shader body */
+                       handle_ngg_outputs_post_1(ctx);
                else
                        handle_vs_outputs_post(ctx, ctx->options->key.vs_common_out.export_prim_id,
                                               ctx->options->key.vs_common_out.export_clip_dists,
@@ -3930,7 +4437,7 @@ handle_shader_outputs_post(struct ac_shader_abi *abi, unsigned max_outputs,
                if (ctx->options->key.vs_common_out.as_es)
                        handle_es_outputs_post(ctx, &ctx->shader_info->tes.es_info);
                else if (ctx->options->key.vs_common_out.as_ngg)
-                       break; /* handled outside of the shader body */
+                       handle_ngg_outputs_post_1(ctx);
                else
                        handle_vs_outputs_post(ctx, ctx->options->key.vs_common_out.export_prim_id,
                                               ctx->options->key.vs_common_out.export_clip_dists,
@@ -4349,7 +4856,7 @@ LLVMModuleRef ac_translate_nir_to_llvm(struct ac_llvm_compiler *ac_llvm,
                if (is_pre_gs_stage(shaders[i]->info.stage) &&
                    ctx.options->key.vs_common_out.as_ngg &&
                    i == shader_count - 1) {
-                       handle_ngg_outputs_post(&ctx);
+                       handle_ngg_outputs_post_2(&ctx);
                } else if (shaders[i]->info.stage == MESA_SHADER_GEOMETRY &&
                           ctx.options->key.vs_common_out.as_ngg) {
                        gfx10_ngg_gs_emit_epilogue_2(&ctx);