[Mesa-dev] [PATCH] glsl: translate transform feedback varyings into low-level representation
Marek Olšák
maraeo at gmail.com
Wed Oct 26 15:28:23 PDT 2011
This adds a function that takes an array of varyings from
glTranformFeedbackVaryingsEXT and generates gl_transform_feedback_info,
which is supposed to be consumed by drivers. Useful for ir_to_mesa
and glsl_to_tgsi.
With Dan McCabe's patch, I think this is all that's needed for transform
feedback GLSL support. This work should probably be better integrated with
Dan's code though (maybe some stuff that's done here should be done
in the linker instead).
What's missing is reporting linker errors (AFAIK). This patch just covers
the post-link part.
The piglit tests ext_transform_feedback-position,separate,interleaved
pass with this.
---
src/glsl/Makefile | 1 +
src/glsl/ir.h | 15 ++
src/glsl/ir_set_transform_feedback_outs.cpp | 299 +++++++++++++++++++++++++++
src/mesa/main/mtypes.h | 12 +
4 files changed, 327 insertions(+), 0 deletions(-)
create mode 100644 src/glsl/ir_set_transform_feedback_outs.cpp
diff --git a/src/glsl/Makefile b/src/glsl/Makefile
index 504f1fb..f3b8e2e 100644
--- a/src/glsl/Makefile
+++ b/src/glsl/Makefile
@@ -48,6 +48,7 @@ CXX_SOURCES = \
ir_reader.cpp \
ir_rvalue_visitor.cpp \
ir_set_program_inouts.cpp \
+ ir_set_transform_feedback_outs.cpp \
ir_validate.cpp \
ir_variable.cpp \
ir_variable_refcount.cpp \
diff --git a/src/glsl/ir.h b/src/glsl/ir.h
index b707634..c17473c 100644
--- a/src/glsl/ir.h
+++ b/src/glsl/ir.h
@@ -1685,4 +1685,19 @@ extern char *
prototype_string(const glsl_type *return_type, const char *name,
exec_list *parameters);
+/**
+ * Set transform feedback output locations and other related info
+ * in gl_program.
+ *
+ * \param shaderprog The inputs are the parameters
+ * from glTransformFeedbackVaryings expected
+ * to be in gl_shader_program::TransformFeedback.
+ *
+ * \param info Where the resulting info is stored.
+ */
+extern void
+do_set_transform_feedback_outs(exec_list *instructions,
+ struct gl_shader_program *shaderprog,
+ struct gl_transform_feedback_info *info);
+
#endif /* IR_H */
diff --git a/src/glsl/ir_set_transform_feedback_outs.cpp b/src/glsl/ir_set_transform_feedback_outs.cpp
new file mode 100644
index 0000000..0138024
--- /dev/null
+++ b/src/glsl/ir_set_transform_feedback_outs.cpp
@@ -0,0 +1,299 @@
+/*
+ * Copyright © 2010 Intel Corporation
+ * Copyright © 2011 Marek Olšák <maraeo at gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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.
+ */
+
+/**
+ * \file ir_set_transform_feedback_outs.cpp
+ *
+ * Used to obtain info about shader outputs from the GLSL IR
+ * for transform feedback.
+ * The driver codegen backend needs to know locations of the outputs
+ * which are to be stored in transform feedback buffers and the number
+ * of components each such output has.
+ *
+ * This is similar to ir_set_program_inouts.
+ */
+
+extern "C" {
+#include "program/hash_table.h"
+}
+#include "main/core.h"
+#include "ir.h"
+#include "ir_visitor.h"
+#include "glsl_types.h"
+#include <cmath>
+
+
+struct tfeedback_decl {
+ char name[1024];
+ bool is_array;
+ unsigned array_index;
+};
+
+
+/* This expects expressions of the form "var" and "var[i]",
+ * where i is a literal.
+ *
+ * We don't have to be pedantic about what is a valid GLSL variable name,
+ * because any variable with an invalid name can't exist in the IR anyway. */
+static bool parse_tfeedback_decl(const char *input,
+ struct tfeedback_decl *decl)
+{
+ unsigned name_index = 0;
+
+ memset(decl, 0, sizeof(*decl));
+
+ /* Parse the variable name. */
+ while (*input &&
+ ((*input > 'a' && *input < 'z') ||
+ (*input > 'A' && *input < 'Z') ||
+ (*input > '0' && *input < '9') ||
+ *input == '_') &&
+ name_index < Elements(decl->name)-1) {
+ decl->name[name_index++] = *input;
+ input++;
+ }
+
+ if (!*input) {
+ return true; /* Found: "var" */
+ }
+
+ /* Parse the array index. */
+ if (*input == '[') {
+ input++;
+
+ if (*input && *input >= '0' && *input <= '9' &&
+ sscanf(input, "%u", &decl->array_index) == 1) {
+ decl->is_array = true;
+ input += (unsigned)(log(decl->array_index)/log(10)) + 1;
+
+ if (*input && *input == ']') {
+ input++;
+ if (!*input) {
+ return true; /* Found: "var[i]" */
+ }
+ }
+ }
+ }
+
+ return false;
+}
+
+
+class ir_set_transform_feedback_outs : public ir_hierarchical_visitor {
+public:
+ ir_set_transform_feedback_outs(struct gl_shader_program *shaderprog,
+ struct gl_transform_feedback_info *info);
+
+ ~ir_set_transform_feedback_outs()
+ {
+ hash_table_dtor(this->ht);
+ }
+
+ void finalize();
+
+ virtual ir_visitor_status visit_enter(ir_dereference_array *);
+ virtual ir_visitor_status visit_enter(ir_function_signature *);
+ virtual ir_visitor_status visit(ir_dereference_variable *);
+ virtual ir_visitor_status visit(ir_variable *);
+
+private:
+ void get_output(ir_variable *var, unsigned start_index,
+ unsigned matrix_cols, unsigned length);
+
+ struct hash_table *ht;
+ struct gl_transform_feedback_info *info;
+ GLenum buffer_mode;
+
+ unsigned num_outputs;
+ struct {
+ struct tfeedback_decl decl;
+ unsigned location;
+ unsigned num_components;
+ unsigned num_vectors; /* location+0 up to location+(num_vectors-1)
+ should be stored. */
+ } output[MAX_PROGRAM_OUTPUTS];
+};
+
+
+ir_set_transform_feedback_outs::ir_set_transform_feedback_outs(
+ struct gl_shader_program *shaderprog,
+ struct gl_transform_feedback_info *info)
+ : info(info), buffer_mode(shaderprog->TransformFeedback.BufferMode),
+ num_outputs(0)
+{
+ GLuint num_names = shaderprog->TransformFeedback.NumVarying;
+ GLchar **names = shaderprog->TransformFeedback.VaryingNames;
+ unsigned i;
+
+ this->ht = hash_table_ctor(0,
+ hash_table_pointer_hash,
+ hash_table_pointer_compare);
+
+ /* Parse names. */
+ /* XXX maybe just parse the names in the linker and not here, because
+ * the linker must parse them anyway to see if all the names are existing
+ * varyings and report an error if not. */
+ for (i = 0; i < num_names; i++) {
+ if (!parse_tfeedback_decl(names[i], &this->output[i].decl)) {
+ /* shouldn't happen, the linker should have validated
+ * all the inputs */
+ assert(0);
+ memset(&this->output[i].decl, 0, sizeof(struct tfeedback_decl));
+ }
+ }
+ this->num_outputs = num_names;
+}
+
+void
+ir_set_transform_feedback_outs::finalize()
+{
+ unsigned i, v, final_num_outs = 0;
+
+ for (i = 0; i < this->num_outputs; i++) {
+ for (v = 0; v < this->output[i].num_vectors; v++) {
+ info->Outputs[final_num_outs].OutputRegister =
+ this->output[i].location + v;
+ info->Outputs[final_num_outs].NumComponents =
+ this->output[i].num_components;
+ info->Outputs[final_num_outs].OutputBuffer =
+ this->buffer_mode == GL_SEPARATE_ATTRIBS ? i : 0;
+ final_num_outs++;
+ }
+ }
+
+ info->NumOutputs = final_num_outs;
+}
+
+void
+ir_set_transform_feedback_outs::get_output(ir_variable *var,
+ unsigned start_index,
+ unsigned matrix_cols,
+ unsigned length)
+{
+ unsigned i;
+
+ assert(var->mode == ir_var_out);
+
+ for (i = 0; i < this->num_outputs; i++) {
+ if (strcmp(var->name, this->output[i].decl.name) == 0) {
+ if (var->type->is_array()) {
+ /* Array variable */
+ if (this->output[i].decl.is_array &&
+ this->output[i].decl.array_index >= start_index &&
+ this->output[i].decl.array_index < start_index+length) {
+ this->output[i].location =
+ var->location +
+ this->output[i].decl.array_index * matrix_cols;
+ this->output[i].num_components =
+ var->type->fields.array->vector_elements;
+ this->output[i].num_vectors = matrix_cols;
+ }
+ } else {
+ /* Regular variable (scalar, vector, or matrix) */
+ this->output[i].location = var->location + start_index * matrix_cols;
+ this->output[i].num_components = var->type->vector_elements;
+ this->output[i].num_vectors = length * matrix_cols;
+ }
+ }
+ }
+}
+
+
+ir_visitor_status
+ir_set_transform_feedback_outs::visit(ir_dereference_variable *ir)
+{
+ if (hash_table_find(this->ht, ir->var) == NULL)
+ return visit_continue;
+
+ if (ir->type->is_array()) {
+ this->get_output(ir->var, 0, ir->type->fields.array->matrix_columns,
+ ir->type->length);
+ } else {
+ this->get_output(ir->var, 0, ir->type->matrix_columns, 1);
+ }
+
+ return visit_continue;
+}
+
+
+ir_visitor_status
+ir_set_transform_feedback_outs::visit_enter(ir_dereference_array *ir)
+{
+ ir_dereference_variable *deref_var;
+ ir_constant *index = ir->array_index->as_constant();
+ deref_var = ir->array->as_dereference_variable();
+ ir_variable *var = NULL;
+
+ /* Check that we're dereferencing a shader out */
+ if (deref_var)
+ var = (ir_variable *)hash_table_find(this->ht, deref_var->var);
+
+ if (index && var) {
+ int mat_col = 1;
+
+ if (deref_var->type->is_array() &&
+ deref_var->type->fields.array->is_matrix()) {
+ mat_col = deref_var->type->fields.array->matrix_columns;
+ }
+
+ this->get_output(var, index->value.i[0], mat_col, 1);
+ return visit_continue_with_parent;
+ }
+
+ return visit_continue;
+}
+
+
+ir_visitor_status
+ir_set_transform_feedback_outs::visit(ir_variable *ir)
+{
+ if (ir->mode == ir_var_out) {
+ hash_table_insert(this->ht, ir, ir);
+ }
+
+ return visit_continue;
+}
+
+
+ir_visitor_status
+ir_set_transform_feedback_outs::visit_enter(ir_function_signature *ir)
+{
+ /* We don't want to descend into the function parameters and
+ * consider them as shader inputs or outputs.
+ */
+ visit_list_elements(this, &ir->body);
+ return visit_continue_with_parent;
+}
+
+
+void
+do_set_transform_feedback_outs(exec_list *instructions,
+ struct gl_shader_program *shaderprog,
+ struct gl_transform_feedback_info *info)
+{
+ ir_set_transform_feedback_outs v(shaderprog, info);
+
+ visit_list_elements(&v, instructions);
+ v.finalize();
+}
diff --git a/src/mesa/main/mtypes.h b/src/mesa/main/mtypes.h
index 719dff3..79cdcec 100644
--- a/src/mesa/main/mtypes.h
+++ b/src/mesa/main/mtypes.h
@@ -1795,6 +1795,16 @@ struct prog_instruction;
struct gl_program_parameter_list;
struct gl_uniform_list;
+/** Post-link transform feedback info. */
+struct gl_transform_feedback_info {
+ unsigned NumOutputs;
+
+ struct {
+ unsigned OutputRegister;
+ unsigned OutputBuffer;
+ unsigned NumComponents;
+ } Outputs[MAX_PROGRAM_OUTPUTS];
+};
/**
* Base class for any kind of program object
@@ -1819,6 +1829,8 @@ struct gl_program
GLbitfield SamplersUsed; /**< Bitfield of which samplers are used */
GLbitfield ShadowSamplers; /**< Texture units used for shadow sampling. */
+ /** Post-link transform feedback info. */
+ struct gl_transform_feedback_info TransformFeedback;
/** Named parameters, constants, etc. from program text */
struct gl_program_parameter_list *Parameters;
--
1.7.4.1
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