extern "C" const unsigned *
brw_compile_tcs(const struct brw_compiler *compiler,
void *log_data,
void *mem_ctx,
const struct brw_tcs_prog_key *key,
struct brw_tcs_prog_data *prog_data,
const nir_shader *src_shader,
int shader_time_index,
unsigned *final_assembly_size,
char **error_str)
{
const struct gen_device_info *devinfo = compiler->devinfo;
struct brw_vue_prog_data *vue_prog_data = &prog_data->base;
const bool is_scalar = compiler->scalar_stage[MESA_SHADER_TESS_CTRL];
nir_shader *nir = nir_shader_clone(mem_ctx, src_shader);
nir->info->outputs_written = key->outputs_written;
nir->info->patch_outputs_written = key->patch_outputs_written;
struct brw_vue_map input_vue_map;
brw_compute_vue_map(devinfo, &input_vue_map, nir->info->inputs_read,
nir->info->separate_shader);
brw_compute_tess_vue_map(&vue_prog_data->vue_map,
nir->info->outputs_written,
nir->info->patch_outputs_written);
nir = brw_nir_apply_sampler_key(nir, devinfo, &key->tex, is_scalar);
brw_nir_lower_vue_inputs(nir, is_scalar, &input_vue_map);
brw_nir_lower_tcs_outputs(nir, &vue_prog_data->vue_map);
if (key->quads_workaround)
brw_nir_apply_tcs_quads_workaround(nir);
nir = brw_postprocess_nir(nir, compiler->devinfo, is_scalar);
if (is_scalar)
prog_data->instances = DIV_ROUND_UP(nir->info->tcs.vertices_out, 8);
else
prog_data->instances = DIV_ROUND_UP(nir->info->tcs.vertices_out, 2);
/* Compute URB entry size. The maximum allowed URB entry size is 32k.
* That divides up as follows:
*
* 32 bytes for the patch header (tessellation factors)
* 480 bytes for per-patch varyings (a varying component is 4 bytes and
* gl_MaxTessPatchComponents = 120)
* 16384 bytes for per-vertex varyings (a varying component is 4 bytes,
* gl_MaxPatchVertices = 32 and
* gl_MaxTessControlOutputComponents = 128)
*
* 15808 bytes left for varying packing overhead
*/
const int num_per_patch_slots = vue_prog_data->vue_map.num_per_patch_slots;
const int num_per_vertex_slots = vue_prog_data->vue_map.num_per_vertex_slots;
unsigned output_size_bytes = 0;
/* Note that the patch header is counted in num_per_patch_slots. */
output_size_bytes += num_per_patch_slots * 16;
output_size_bytes += nir->info->tcs.vertices_out * num_per_vertex_slots * 16;
assert(output_size_bytes >= 1);
if (output_size_bytes > GEN7_MAX_HS_URB_ENTRY_SIZE_BYTES)
return NULL;
/* URB entry sizes are stored as a multiple of 64 bytes. */
vue_prog_data->urb_entry_size = ALIGN(output_size_bytes, 64) / 64;
/* HS does not use the usual payload pushing from URB to GRFs,
* because we don't have enough registers for a full-size payload, and
* the hardware is broken on Haswell anyway.
*/
vue_prog_data->urb_read_length = 0;
if (unlikely(INTEL_DEBUG & DEBUG_TCS)) {
fprintf(stderr, "TCS Input ");
brw_print_vue_map(stderr, &input_vue_map);
fprintf(stderr, "TCS Output ");
brw_print_vue_map(stderr, &vue_prog_data->vue_map);
}
if (is_scalar) {
fs_visitor v(compiler, log_data, mem_ctx, (void *) key,
&prog_data->base.base, NULL, nir, 8,
shader_time_index, &input_vue_map);
if (!v.run_tcs_single_patch()) {
if (error_str)
*error_str = ralloc_strdup(mem_ctx, v.fail_msg);
return NULL;
}
prog_data->base.base.dispatch_grf_start_reg = v.payload.num_regs;
prog_data->base.dispatch_mode = DISPATCH_MODE_SIMD8;
fs_generator g(compiler, log_data, mem_ctx, (void *) key,
&prog_data->base.base, v.promoted_constants, false,
MESA_SHADER_TESS_CTRL);
if (unlikely(INTEL_DEBUG & DEBUG_TCS)) {
g.enable_debug(ralloc_asprintf(mem_ctx,
"%s tessellation control shader %s",
nir->info->label ? nir->info->label
: "unnamed",
nir->info->name));
}
g.generate_code(v.cfg, 8);
return g.get_assembly(final_assembly_size);
} else {
vec4_tcs_visitor v(compiler, log_data, key, prog_data,
nir, mem_ctx, shader_time_index, &input_vue_map);
if (!v.run()) {
if (error_str)
*error_str = ralloc_strdup(mem_ctx, v.fail_msg);
return NULL;
}
if (unlikely(INTEL_DEBUG & DEBUG_TCS))
v.dump_instructions();
return brw_vec4_generate_assembly(compiler, log_data, mem_ctx, nir,
&prog_data->base, v.cfg,
final_assembly_size);
}
}
extern "C" const unsigned *
brw_compile_gs(const struct brw_compiler *compiler, void *log_data,
void *mem_ctx,
const struct brw_gs_prog_key *key,
struct brw_gs_prog_data *prog_data,
const nir_shader *src_shader,
struct gl_shader_program *shader_prog,
int shader_time_index,
unsigned *final_assembly_size,
char **error_str)
{
struct brw_gs_compile c;
memset(&c, 0, sizeof(c));
c.key = *key;
const bool is_scalar = compiler->scalar_stage[MESA_SHADER_GEOMETRY];
nir_shader *shader = nir_shader_clone(mem_ctx, src_shader);
/* The GLSL linker will have already matched up GS inputs and the outputs
* of prior stages. The driver does extend VS outputs in some cases, but
* only for legacy OpenGL or Gen4-5 hardware, neither of which offer
* geometry shader support. So we can safely ignore that.
*
* For SSO pipelines, we use a fixed VUE map layout based on variable
* locations, so we can rely on rendezvous-by-location making this work.
*/
GLbitfield64 inputs_read = shader->info->inputs_read;
brw_compute_vue_map(compiler->devinfo,
&c.input_vue_map, inputs_read,
shader->info->separate_shader);
shader = brw_nir_apply_sampler_key(shader, compiler->devinfo, &key->tex,
is_scalar);
brw_nir_lower_vue_inputs(shader, is_scalar, &c.input_vue_map);
brw_nir_lower_vue_outputs(shader, is_scalar);
shader = brw_postprocess_nir(shader, compiler->devinfo, is_scalar);
prog_data->base.clip_distance_mask =
((1 << shader->info->clip_distance_array_size) - 1);
prog_data->base.cull_distance_mask =
((1 << shader->info->cull_distance_array_size) - 1) <<
shader->info->clip_distance_array_size;
prog_data->include_primitive_id =
(shader->info->system_values_read & (1 << SYSTEM_VALUE_PRIMITIVE_ID)) != 0;
prog_data->invocations = shader->info->gs.invocations;
if (compiler->devinfo->gen >= 8)
prog_data->static_vertex_count = nir_gs_count_vertices(shader);
if (compiler->devinfo->gen >= 7) {
if (shader->info->gs.output_primitive == GL_POINTS) {
/* When the output type is points, the geometry shader may output data
* to multiple streams, and EndPrimitive() has no effect. So we
* configure the hardware to interpret the control data as stream ID.
*/
prog_data->control_data_format = GEN7_GS_CONTROL_DATA_FORMAT_GSCTL_SID;
/* We only have to emit control bits if we are using streams */
if (shader_prog && shader_prog->Geom.UsesStreams)
c.control_data_bits_per_vertex = 2;
else
c.control_data_bits_per_vertex = 0;
} else {
/* When the output type is triangle_strip or line_strip, EndPrimitive()
* may be used to terminate the current strip and start a new one
* (similar to primitive restart), and outputting data to multiple
* streams is not supported. So we configure the hardware to interpret
* the control data as EndPrimitive information (a.k.a. "cut bits").
*/
prog_data->control_data_format = GEN7_GS_CONTROL_DATA_FORMAT_GSCTL_CUT;
/* We only need to output control data if the shader actually calls
* EndPrimitive().
*/
c.control_data_bits_per_vertex =
shader->info->gs.uses_end_primitive ? 1 : 0;
}
} else {
/* There are no control data bits in gen6. */
c.control_data_bits_per_vertex = 0;
/* If it is using transform feedback, enable it */
if (shader->info->has_transform_feedback_varyings)
prog_data->gen6_xfb_enabled = true;
else
prog_data->gen6_xfb_enabled = false;
}
c.control_data_header_size_bits =
shader->info->gs.vertices_out * c.control_data_bits_per_vertex;
/* 1 HWORD = 32 bytes = 256 bits */
prog_data->control_data_header_size_hwords =
ALIGN(c.control_data_header_size_bits, 256) / 256;
/* Compute the output vertex size.
*
* From the Ivy Bridge PRM, Vol2 Part1 7.2.1.1 STATE_GS - Output Vertex
* Size (p168):
*
* [0,62] indicating [1,63] 16B units
*
* Specifies the size of each vertex stored in the GS output entry
* (following any Control Header data) as a number of 128-bit units
* (minus one).
*
* Programming Restrictions: The vertex size must be programmed as a
* multiple of 32B units with the following exception: Rendering is
* disabled (as per SOL stage state) and the vertex size output by the
* GS thread is 16B.
*
* If rendering is enabled (as per SOL state) the vertex size must be
* programmed as a multiple of 32B units. In other words, the only time
* software can program a vertex size with an odd number of 16B units
* is when rendering is disabled.
*
* Note: B=bytes in the above text.
*
* It doesn't seem worth the extra trouble to optimize the case where the
* vertex size is 16B (especially since this would require special-casing
* the GEN assembly that writes to the URB). So we just set the vertex
* size to a multiple of 32B (2 vec4's) in all cases.
*
* The maximum output vertex size is 62*16 = 992 bytes (31 hwords). We
* budget that as follows:
*
* 512 bytes for varyings (a varying component is 4 bytes and
* gl_MaxGeometryOutputComponents = 128)
* 16 bytes overhead for VARYING_SLOT_PSIZ (each varying slot is 16
* bytes)
* 16 bytes overhead for gl_Position (we allocate it a slot in the VUE
* even if it's not used)
* 32 bytes overhead for gl_ClipDistance (we allocate it 2 VUE slots
* whenever clip planes are enabled, even if the shader doesn't
* write to gl_ClipDistance)
* 16 bytes overhead since the VUE size must be a multiple of 32 bytes
* (see below)--this causes up to 1 VUE slot to be wasted
* 400 bytes available for varying packing overhead
*
* Worst-case varying packing overhead is 3/4 of a varying slot (12 bytes)
* per interpolation type, so this is plenty.
*
*/
unsigned output_vertex_size_bytes = prog_data->base.vue_map.num_slots * 16;
assert(compiler->devinfo->gen == 6 ||
output_vertex_size_bytes <= GEN7_MAX_GS_OUTPUT_VERTEX_SIZE_BYTES);
prog_data->output_vertex_size_hwords =
ALIGN(output_vertex_size_bytes, 32) / 32;
/* Compute URB entry size. The maximum allowed URB entry size is 32k.
* That divides up as follows:
*
* 64 bytes for the control data header (cut indices or StreamID bits)
* 4096 bytes for varyings (a varying component is 4 bytes and
* gl_MaxGeometryTotalOutputComponents = 1024)
* 4096 bytes overhead for VARYING_SLOT_PSIZ (each varying slot is 16
* bytes/vertex and gl_MaxGeometryOutputVertices is 256)
* 4096 bytes overhead for gl_Position (we allocate it a slot in the VUE
* even if it's not used)
* 8192 bytes overhead for gl_ClipDistance (we allocate it 2 VUE slots
* whenever clip planes are enabled, even if the shader doesn't
* write to gl_ClipDistance)
* 4096 bytes overhead since the VUE size must be a multiple of 32
* bytes (see above)--this causes up to 1 VUE slot to be wasted
* 8128 bytes available for varying packing overhead
*
* Worst-case varying packing overhead is 3/4 of a varying slot per
* interpolation type, which works out to 3072 bytes, so this would allow
* us to accommodate 2 interpolation types without any danger of running
* out of URB space.
*
* In practice, the risk of running out of URB space is very small, since
* the above figures are all worst-case, and most of them scale with the
* number of output vertices. So we'll just calculate the amount of space
* we need, and if it's too large, fail to compile.
*
* The above is for gen7+ where we have a single URB entry that will hold
* all the output. In gen6, we will have to allocate URB entries for every
* vertex we emit, so our URB entries only need to be large enough to hold
* a single vertex. Also, gen6 does not have a control data header.
*/
unsigned output_size_bytes;
if (compiler->devinfo->gen >= 7) {
output_size_bytes =
prog_data->output_vertex_size_hwords * 32 * shader->info->gs.vertices_out;
output_size_bytes += 32 * prog_data->control_data_header_size_hwords;
} else {
output_size_bytes = prog_data->output_vertex_size_hwords * 32;
}
/* Broadwell stores "Vertex Count" as a full 8 DWord (32 byte) URB output,
* which comes before the control header.
*/
if (compiler->devinfo->gen >= 8)
output_size_bytes += 32;
/* Shaders can technically set max_vertices = 0, at which point we
* may have a URB size of 0 bytes. Nothing good can come from that,
* so enforce a minimum size.
*/
if (output_size_bytes == 0)
output_size_bytes = 1;
unsigned max_output_size_bytes = GEN7_MAX_GS_URB_ENTRY_SIZE_BYTES;
if (compiler->devinfo->gen == 6)
max_output_size_bytes = GEN6_MAX_GS_URB_ENTRY_SIZE_BYTES;
if (output_size_bytes > max_output_size_bytes)
return NULL;
/* URB entry sizes are stored as a multiple of 64 bytes in gen7+ and
* a multiple of 128 bytes in gen6.
*/
if (compiler->devinfo->gen >= 7)
prog_data->base.urb_entry_size = ALIGN(output_size_bytes, 64) / 64;
else
prog_data->base.urb_entry_size = ALIGN(output_size_bytes, 128) / 128;
prog_data->output_topology =
get_hw_prim_for_gl_prim(shader->info->gs.output_primitive);
prog_data->vertices_in = shader->info->gs.vertices_in;
/* GS inputs are read from the VUE 256 bits (2 vec4's) at a time, so we
* need to program a URB read length of ceiling(num_slots / 2).
*/
prog_data->base.urb_read_length = (c.input_vue_map.num_slots + 1) / 2;
/* Now that prog_data setup is done, we are ready to actually compile the
* program.
*/
if (unlikely(INTEL_DEBUG & DEBUG_GS)) {
fprintf(stderr, "GS Input ");
brw_print_vue_map(stderr, &c.input_vue_map);
fprintf(stderr, "GS Output ");
brw_print_vue_map(stderr, &prog_data->base.vue_map);
}
if (is_scalar) {
fs_visitor v(compiler, log_data, mem_ctx, &c, prog_data, shader,
shader_time_index);
if (v.run_gs()) {
prog_data->base.dispatch_mode = DISPATCH_MODE_SIMD8;
prog_data->base.base.dispatch_grf_start_reg = v.payload.num_regs;
fs_generator g(compiler, log_data, mem_ctx, &c.key,
&prog_data->base.base, v.promoted_constants,
false, MESA_SHADER_GEOMETRY);
if (unlikely(INTEL_DEBUG & DEBUG_GS)) {
const char *label =
shader->info->label ? shader->info->label : "unnamed";
char *name = ralloc_asprintf(mem_ctx, "%s geometry shader %s",
label, shader->info->name);
g.enable_debug(name);
}
g.generate_code(v.cfg, 8);
return g.get_assembly(final_assembly_size);
}
}
if (compiler->devinfo->gen >= 7) {
/* Compile the geometry shader in DUAL_OBJECT dispatch mode, if we can do
* so without spilling. If the GS invocations count > 1, then we can't use
* dual object mode.
*/
if (prog_data->invocations <= 1 &&
likely(!(INTEL_DEBUG & DEBUG_NO_DUAL_OBJECT_GS))) {
prog_data->base.dispatch_mode = DISPATCH_MODE_4X2_DUAL_OBJECT;
vec4_gs_visitor v(compiler, log_data, &c, prog_data, shader,
mem_ctx, true /* no_spills */, shader_time_index);
if (v.run()) {
return brw_vec4_generate_assembly(compiler, log_data, mem_ctx,
shader, &prog_data->base, v.cfg,
final_assembly_size);
}
}
}
/* Either we failed to compile in DUAL_OBJECT mode (probably because it
* would have required spilling) or DUAL_OBJECT mode is disabled. So fall
* back to DUAL_INSTANCED or SINGLE mode, which consumes fewer registers.
*
* FIXME: Single dispatch mode requires that the driver can handle
* interleaving of input registers, but this is already supported (dual
* instance mode has the same requirement). However, to take full advantage
* of single dispatch mode to reduce register pressure we would also need to
* do interleaved outputs, but currently, the vec4 visitor and generator
* classes do not support this, so at the moment register pressure in
* single and dual instance modes is the same.
*
* From the Ivy Bridge PRM, Vol2 Part1 7.2.1.1 "3DSTATE_GS"
* "If InstanceCount>1, DUAL_OBJECT mode is invalid. Software will likely
* want to use DUAL_INSTANCE mode for higher performance, but SINGLE mode
* is also supported. When InstanceCount=1 (one instance per object) software
* can decide which dispatch mode to use. DUAL_OBJECT mode would likely be
* the best choice for performance, followed by SINGLE mode."
*
* So SINGLE mode is more performant when invocations == 1 and DUAL_INSTANCE
* mode is more performant when invocations > 1. Gen6 only supports
* SINGLE mode.
*/
if (prog_data->invocations <= 1 || compiler->devinfo->gen < 7)
prog_data->base.dispatch_mode = DISPATCH_MODE_4X1_SINGLE;
else
prog_data->base.dispatch_mode = DISPATCH_MODE_4X2_DUAL_INSTANCE;
vec4_gs_visitor *gs = NULL;
const unsigned *ret = NULL;
if (compiler->devinfo->gen >= 7)
gs = new vec4_gs_visitor(compiler, log_data, &c, prog_data,
shader, mem_ctx, false /* no_spills */,
shader_time_index);
else
gs = new gen6_gs_visitor(compiler, log_data, &c, prog_data, shader_prog,
shader, mem_ctx, false /* no_spills */,
shader_time_index);
if (!gs->run()) {
if (error_str)
*error_str = ralloc_strdup(mem_ctx, gs->fail_msg);
} else {
ret = brw_vec4_generate_assembly(compiler, log_data, mem_ctx, shader,
&prog_data->base, gs->cfg,
final_assembly_size);
}
delete gs;
return ret;
}
