/* When the primitive changes, set a state bit and re-validate. Not
* the nicest and would rather deal with this by having all the
* programs be immune to the active primitive (ie. cope with all
* possibilities). That may not be realistic however.
*/
static void
brw_set_prim(struct brw_context *brw, const struct _mesa_prim *prim)
{
struct gl_context *ctx = &brw->ctx;
uint32_t hw_prim = get_hw_prim_for_gl_prim(prim->mode);
DBG("PRIM: %s\n", _mesa_enum_to_string(prim->mode));
/* Slight optimization to avoid the GS program when not needed:
*/
if (prim->mode == GL_QUAD_STRIP &&
ctx->Light.ShadeModel != GL_FLAT &&
ctx->Polygon.FrontMode == GL_FILL &&
ctx->Polygon.BackMode == GL_FILL)
hw_prim = _3DPRIM_TRISTRIP;
if (prim->mode == GL_QUADS && prim->count == 4 &&
ctx->Light.ShadeModel != GL_FLAT &&
ctx->Polygon.FrontMode == GL_FILL &&
ctx->Polygon.BackMode == GL_FILL) {
hw_prim = _3DPRIM_TRIFAN;
}
if (hw_prim != brw->primitive) {
brw->primitive = hw_prim;
brw->ctx.NewDriverState |= BRW_NEW_PRIMITIVE;
if (reduced_prim[prim->mode] != brw->reduced_primitive) {
brw->reduced_primitive = reduced_prim[prim->mode];
brw->ctx.NewDriverState |= BRW_NEW_REDUCED_PRIMITIVE;
}
}
}
static void
gen6_set_prim(struct brw_context *brw, const struct _mesa_prim *prim)
{
DBG("PRIM: %s\n", _mesa_enum_to_string(prim->mode));
const uint32_t hw_prim = get_hw_prim_for_gl_prim(prim->mode);
if (hw_prim != brw->primitive) {
brw->primitive = hw_prim;
brw->ctx.NewDriverState |= BRW_NEW_PRIMITIVE;
}
}
static void gen6_set_prim(struct brw_context *brw,
const struct _mesa_prim *prim)
{
uint32_t hw_prim;
DBG("PRIM: %s\n", _mesa_lookup_enum_by_nr(prim->mode));
hw_prim = get_hw_prim_for_gl_prim(prim->mode);
if (hw_prim != brw->primitive) {
brw->primitive = hw_prim;
brw->state.dirty.brw |= BRW_NEW_PRIMITIVE;
}
}
static void
gen6_set_prim(struct brw_context *brw, const struct _mesa_prim *prim)
{
const struct gl_context *ctx = &brw->ctx;
uint32_t hw_prim;
DBG("PRIM: %s\n", _mesa_enum_to_string(prim->mode));
if (prim->mode == GL_PATCHES) {
hw_prim = _3DPRIM_PATCHLIST(ctx->TessCtrlProgram.patch_vertices);
} else {
hw_prim = get_hw_prim_for_gl_prim(prim->mode);
}
if (hw_prim != brw->primitive) {
brw->primitive = hw_prim;
brw->ctx.NewDriverState |= BRW_NEW_PRIMITIVE;
if (prim->mode == GL_PATCHES)
brw->ctx.NewDriverState |= BRW_NEW_PATCH_PRIMITIVE;
}
}
bool
brw_codegen_gs_prog(struct brw_context *brw,
struct gl_shader_program *prog,
struct brw_geometry_program *gp,
struct brw_gs_prog_key *key)
{
struct brw_stage_state *stage_state = &brw->gs.base;
struct brw_gs_compile c;
memset(&c, 0, sizeof(c));
c.key = *key;
c.gp = gp;
c.prog_data.include_primitive_id =
(gp->program.Base.InputsRead & VARYING_BIT_PRIMITIVE_ID) != 0;
c.prog_data.invocations = gp->program.Invocations;
/* Allocate the references to the uniforms that will end up in the
* prog_data associated with the compiled program, and which will be freed
* by the state cache.
*
* Note: param_count needs to be num_uniform_components * 4, since we add
* padding around uniform values below vec4 size, so the worst case is that
* every uniform is a float which gets padded to the size of a vec4.
*/
struct gl_shader *gs = prog->_LinkedShaders[MESA_SHADER_GEOMETRY];
int param_count = gs->num_uniform_components * 4;
/* We also upload clip plane data as uniforms */
param_count += MAX_CLIP_PLANES * 4;
c.prog_data.base.base.param =
rzalloc_array(NULL, const gl_constant_value *, param_count);
c.prog_data.base.base.pull_param =
rzalloc_array(NULL, const gl_constant_value *, param_count);
c.prog_data.base.base.nr_params = param_count;
if (brw->gen >= 7) {
if (gp->program.OutputType == 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.
*/
c.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 (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").
*/
c.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 = gp->program.UsesEndPrimitive ? 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 (prog->TransformFeedback.NumVarying)
c.prog_data.gen6_xfb_enabled = true;
else
c.prog_data.gen6_xfb_enabled = false;
}
c.control_data_header_size_bits =
gp->program.VerticesOut * c.control_data_bits_per_vertex;
/* 1 HWORD = 32 bytes = 256 bits */
c.prog_data.control_data_header_size_hwords =
ALIGN(c.control_data_header_size_bits, 256) / 256;
GLbitfield64 outputs_written = gp->program.Base.OutputsWritten;
/* In order for legacy clipping to work, we need to populate the clip
* distance varying slots whenever clipping is enabled, even if the vertex
* shader doesn't write to gl_ClipDistance.
*/
if (c.key.base.userclip_active) {
outputs_written |= BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST0);
outputs_written |= BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST1);
}
brw_compute_vue_map(brw->intelScreen->devinfo,
&c.prog_data.base.vue_map, outputs_written);
/* 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 = c.prog_data.base.vue_map.num_slots * 16;
assert(brw->gen == 6 ||
output_vertex_size_bytes <= GEN7_MAX_GS_OUTPUT_VERTEX_SIZE_BYTES);
c.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 (brw->gen >= 7) {
output_size_bytes =
c.prog_data.output_vertex_size_hwords * 32 * gp->program.VerticesOut;
output_size_bytes += 32 * c.prog_data.control_data_header_size_hwords;
} else {
output_size_bytes = c.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 (brw->gen >= 8)
output_size_bytes += 32;
assert(output_size_bytes >= 1);
int max_output_size_bytes = GEN7_MAX_GS_URB_ENTRY_SIZE_BYTES;
if (brw->gen == 6)
max_output_size_bytes = GEN6_MAX_GS_URB_ENTRY_SIZE_BYTES;
if (output_size_bytes > max_output_size_bytes)
return false;
/* URB entry sizes are stored as a multiple of 64 bytes in gen7+ and
* a multiple of 128 bytes in gen6.
*/
if (brw->gen >= 7)
c.prog_data.base.urb_entry_size = ALIGN(output_size_bytes, 64) / 64;
else
c.prog_data.base.urb_entry_size = ALIGN(output_size_bytes, 128) / 128;
c.prog_data.output_topology =
get_hw_prim_for_gl_prim(gp->program.OutputType);
brw_compute_vue_map(brw->intelScreen->devinfo,
&c.input_vue_map, c.key.input_varyings);
/* 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).
*/
c.prog_data.base.urb_read_length = (c.input_vue_map.num_slots + 1) / 2;
void *mem_ctx = ralloc_context(NULL);
unsigned program_size;
const unsigned *program =
brw_gs_emit(brw, prog, &c, mem_ctx, &program_size);
if (program == NULL) {
ralloc_free(mem_ctx);
return false;
}
/* Scratch space is used for register spilling */
if (c.base.last_scratch) {
perf_debug("Geometry shader triggered register spilling. "
"Try reducing the number of live vec4 values to "
"improve performance.\n");
c.prog_data.base.base.total_scratch
= brw_get_scratch_size(c.base.last_scratch*REG_SIZE);
brw_get_scratch_bo(brw, &stage_state->scratch_bo,
c.prog_data.base.base.total_scratch *
brw->max_gs_threads);
}
brw_upload_cache(&brw->cache, BRW_CACHE_GS_PROG,
&c.key, sizeof(c.key),
program, program_size,
&c.prog_data, sizeof(c.prog_data),
&stage_state->prog_offset, &brw->gs.prog_data);
ralloc_free(mem_ctx);
return true;
}
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;
}
