From: Nicolai Hähnle <nicolai.haeh...@amd.com>
With merged ESGS shaders, the GS part of a wave may be empty, and the
hardware gets confused if any GS messages are sent from that wave. Since
S_SENDMSG is executed even when EXEC = 0, we have to wrap even
non-monolithic GS shaders in an if-block, so that the entire shader and
hence the S_SENDMSG instructions are skipped in empty waves.
This change is not required for TCS/HS, but applying it there as well
simplifies the code a bit.
Fixes GL45-CTS.geometry_shader.rendering.rendering.*
Cc: mesa-sta...@lists.freedesktop.org
---
src/gallium/drivers/radeonsi/si_shader.c | 74 +++++++++++++----------
src/gallium/drivers/radeonsi/si_shader_internal.h | 3 +
2 files changed, 45 insertions(+), 32 deletions(-)
diff --git a/src/gallium/drivers/radeonsi/si_shader.c
b/src/gallium/drivers/radeonsi/si_shader.c
index 7a44e61..9aeda49 100644
--- a/src/gallium/drivers/radeonsi/si_shader.c
+++ b/src/gallium/drivers/radeonsi/si_shader.c
@@ -2713,20 +2713,23 @@ si_insert_input_ptr_as_2xi32(struct si_shader_context
*ctx, LLVMValueRef ret,
}
/* This only writes the tessellation factor levels. */
static void si_llvm_emit_tcs_epilogue(struct lp_build_tgsi_context *bld_base)
{
struct si_shader_context *ctx = si_shader_context(bld_base);
LLVMValueRef rel_patch_id, invocation_id, tf_lds_offset;
si_copy_tcs_inputs(bld_base);
+ if (ctx->screen->b.chip_class >= GFX9)
+ lp_build_endif(&ctx->merged_wrap_if_state);
+
rel_patch_id = get_rel_patch_id(ctx);
invocation_id = unpack_param(ctx, ctx->param_tcs_rel_ids, 8, 5);
tf_lds_offset = get_tcs_out_current_patch_data_offset(ctx);
/* Return epilog parameters from this function. */
LLVMBuilderRef builder = ctx->gallivm.builder;
LLVMValueRef ret = ctx->return_value;
unsigned vgpr;
if (ctx->screen->b.chip_class >= GFX9) {
@@ -2946,20 +2949,23 @@ static LLVMValueRef si_get_gs_wave_id(struct
si_shader_context *ctx)
else
return LLVMGetParam(ctx->main_fn, ctx->param_gs_wave_id);
}
static void si_llvm_emit_gs_epilogue(struct lp_build_tgsi_context *bld_base)
{
struct si_shader_context *ctx = si_shader_context(bld_base);
ac_build_sendmsg(&ctx->ac, AC_SENDMSG_GS_OP_NOP | AC_SENDMSG_GS_DONE,
si_get_gs_wave_id(ctx));
+
+ if (ctx->screen->b.chip_class >= GFX9)
+ lp_build_endif(&ctx->merged_wrap_if_state);
}
static void si_llvm_emit_vs_epilogue(struct lp_build_tgsi_context *bld_base)
{
struct si_shader_context *ctx = si_shader_context(bld_base);
struct gallivm_state *gallivm = &ctx->gallivm;
struct tgsi_shader_info *info = &ctx->shader->selector->info;
struct si_shader_output_values *outputs = NULL;
int i,j;
@@ -5523,39 +5529,55 @@ static bool si_compile_tgsi_main(struct
si_shader_context *ctx,
break;
default:
assert(!"Unsupported shader type");
return false;
}
create_function(ctx);
preload_ring_buffers(ctx);
/* For GFX9 merged shaders:
- * - Set EXEC. If the prolog is present, set EXEC there instead.
+ * - Set EXEC for the first shader. If the prolog is present, set
+ * EXEC there instead.
* - Add a barrier before the second shader.
+ * - In the second shader, reset EXEC to ~0 and wrap the main part in
+ * an if-statement. This is required for correctness in geometry
+ * shaders, to ensure that empty GS waves do not send GS_EMIT and
+ * GS_CUT messages.
*
- * The same thing for monolithic shaders is done in
- * si_build_wrapper_function.
+ * For monolithic merged shaders, the first shader is wrapped in an
+ * if-block together with its prolog in si_build_wrapper_function.
*/
- if (ctx->screen->b.chip_class >= GFX9 && !is_monolithic) {
- if (sel->info.num_instructions > 1 && /* not empty shader */
+ if (ctx->screen->b.chip_class >= GFX9) {
+ if (!is_monolithic &&
+ sel->info.num_instructions > 1 && /* not empty shader */
(shader->key.as_es || shader->key.as_ls) &&
(ctx->type == PIPE_SHADER_TESS_EVAL ||
(ctx->type == PIPE_SHADER_VERTEX &&
!sel->vs_needs_prolog))) {
si_init_exec_from_input(ctx,
ctx->param_merged_wave_info, 0);
} else if (ctx->type == PIPE_SHADER_TESS_CTRL ||
ctx->type == PIPE_SHADER_GEOMETRY) {
- si_init_exec_from_input(ctx,
- ctx->param_merged_wave_info, 8);
+ if (!is_monolithic)
+ si_init_exec_full_mask(ctx);
+
+ /* The barrier must execute for all shaders in a
+ * threadgroup.
+ */
si_llvm_emit_barrier(NULL, bld_base, NULL);
+
+ LLVMValueRef num_threads = unpack_param(ctx,
ctx->param_merged_wave_info, 8, 8);
+ LLVMValueRef ena =
+ LLVMBuildICmp(ctx->ac.builder, LLVMIntULT,
+ ac_get_thread_id(&ctx->ac),
num_threads, "");
+ lp_build_if(&ctx->merged_wrap_if_state, &ctx->gallivm,
ena);
}
}
if (ctx->type == PIPE_SHADER_GEOMETRY) {
int i;
for (i = 0; i < 4; i++) {
ctx->gs_next_vertex[i] =
lp_build_alloca(&ctx->gallivm,
ctx->i32, "");
}
@@ -6012,29 +6034,23 @@ static void si_build_wrapper_function(struct
si_shader_context *ctx,
LLVMValueRef in[48];
LLVMValueRef ret;
LLVMTypeRef ret_type;
unsigned out_idx = 0;
num_params = LLVMCountParams(parts[part]);
assert(num_params <= ARRAY_SIZE(param_types));
/* Merged shaders are executed conditionally depending
* on the number of enabled threads passed in the input SGPRs.
*/
- if (is_merged_shader(ctx->shader) &&
- (part == 0 || part == next_shader_first_part)) {
+ if (is_merged_shader(ctx->shader) && part == 0) {
LLVMValueRef ena, count = initial[3];
- /* The thread count for the 2nd shader is at bit-offset
8. */
- if (part == next_shader_first_part) {
- count = LLVMBuildLShr(builder, count,
- LLVMConstInt(ctx->i32, 8,
0), "");
- }
count = LLVMBuildAnd(builder, count,
LLVMConstInt(ctx->i32, 0x7f, 0),
"");
ena = LLVMBuildICmp(builder, LLVMIntULT,
ac_get_thread_id(&ctx->ac), count,
"");
lp_build_if(&if_state, &ctx->gallivm, ena);
}
/* Derive arguments for the next part from outputs of the
* previous one.
*/
@@ -6077,40 +6093,34 @@ static void si_build_wrapper_function(struct
si_shader_context *ctx,
}
}
in[param_idx] = arg;
out_idx += param_size;
}
ret = LLVMBuildCall(builder, parts[part], in, num_params, "");
if (is_merged_shader(ctx->shader) &&
- (part + 1 == next_shader_first_part ||
- part + 1 == num_parts)) {
+ part + 1 == next_shader_first_part) {
lp_build_endif(&if_state);
- if (part + 1 == next_shader_first_part) {
- /* A barrier is required between 2 merged
shaders. */
- si_llvm_emit_barrier(NULL, &ctx->bld_base,
NULL);
-
- /* The second half of the merged shader should
use
- * the inputs from the toplevel (wrapper)
function,
- * not the return value from the last call.
- *
- * That's because the last call was executed
condi-
- * tionally, so we can't consume it in the main
- * block.
- */
- memcpy(out, initial, sizeof(initial));
- num_out = initial_num_out;
- num_out_sgpr = initial_num_out_sgpr;
- }
+ /* The second half of the merged shader should use
+ * the inputs from the toplevel (wrapper) function,
+ * not the return value from the last call.
+ *
+ * That's because the last call was executed condi-
+ * tionally, so we can't consume it in the main
+ * block.
+ */
+ memcpy(out, initial, sizeof(initial));
+ num_out = initial_num_out;
+ num_out_sgpr = initial_num_out_sgpr;
continue;
}
/* Extract the returned GPRs. */
ret_type = LLVMTypeOf(ret);
num_out = 0;
num_out_sgpr = 0;
if (LLVMGetTypeKind(ret_type) != LLVMVoidTypeKind) {
assert(LLVMGetTypeKind(ret_type) == LLVMStructTypeKind);
diff --git a/src/gallium/drivers/radeonsi/si_shader_internal.h
b/src/gallium/drivers/radeonsi/si_shader_internal.h
index 3556e69..3f127cf 100644
--- a/src/gallium/drivers/radeonsi/si_shader_internal.h
+++ b/src/gallium/drivers/radeonsi/si_shader_internal.h
@@ -18,20 +18,21 @@
* THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
* DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
* OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
* USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#ifndef SI_SHADER_PRIVATE_H
#define SI_SHADER_PRIVATE_H
#include "si_shader.h"
+#include "gallivm/lp_bld_flow.h"
#include "gallivm/lp_bld_init.h"
#include "gallivm/lp_bld_tgsi.h"
#include "tgsi/tgsi_parse.h"
#include "ac_llvm_util.h"
#include "ac_llvm_build.h"
#include <llvm-c/Core.h>
#include <llvm-c/TargetMachine.h>
struct pipe_debug_callback;
@@ -98,20 +99,22 @@ struct si_shader_context {
unsigned temps_count;
LLVMValueRef system_values[RADEON_LLVM_MAX_SYSTEM_VALUES];
LLVMValueRef *imms;
unsigned imms_num;
struct si_llvm_flow *flow;
unsigned flow_depth;
unsigned flow_depth_max;
+ struct lp_build_if_state merged_wrap_if_state;
+
struct tgsi_array_info *temp_arrays;
LLVMValueRef *temp_array_allocas;
LLVMValueRef undef_alloca;
LLVMValueRef main_fn;
LLVMTypeRef return_type;
/* Parameter indices for LLVMGetParam. */
int param_rw_buffers;
--
2.9.3
_______________________________________________
mesa-dev mailing list
mesa-dev@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/mesa-dev
