[Mesa-dev] [PATCH 1/2] glsl: move loop analysis helper to loop_analysis.cpp
Timothy Arceri
tarceri at itsqueeze.com
Tue Sep 19 02:14:11 UTC 2017
---
src/compiler/glsl/loop_analysis.cpp | 139 ++++++++++++++++++++++++++++++++++++
src/compiler/glsl/loop_analysis.h | 7 --
src/compiler/glsl/loop_controls.cpp | 139 ------------------------------------
3 files changed, 139 insertions(+), 146 deletions(-)
diff --git a/src/compiler/glsl/loop_analysis.cpp b/src/compiler/glsl/loop_analysis.cpp
index b9bae435368..81a07f78f8f 100644
--- a/src/compiler/glsl/loop_analysis.cpp
+++ b/src/compiler/glsl/loop_analysis.cpp
@@ -32,6 +32,145 @@ static bool all_expression_operands_are_loop_constant(ir_rvalue *,
static ir_rvalue *get_basic_induction_increment(ir_assignment *, hash_table *);
+/**
+ * Find an initializer of a variable outside a loop
+ *
+ * Works backwards from the loop to find the pre-loop value of the variable.
+ * This is used, for example, to find the initial value of loop induction
+ * variables.
+ *
+ * \param loop Loop where \c var is an induction variable
+ * \param var Variable whose initializer is to be found
+ *
+ * \return
+ * The \c ir_rvalue assigned to the variable outside the loop. May return
+ * \c NULL if no initializer can be found.
+ */
+static ir_rvalue *
+find_initial_value(ir_loop *loop, ir_variable *var)
+{
+ for (exec_node *node = loop->prev; !node->is_head_sentinel();
+ node = node->prev) {
+ ir_instruction *ir = (ir_instruction *) node;
+
+ switch (ir->ir_type) {
+ case ir_type_call:
+ case ir_type_loop:
+ case ir_type_loop_jump:
+ case ir_type_return:
+ case ir_type_if:
+ return NULL;
+
+ case ir_type_function:
+ case ir_type_function_signature:
+ assert(!"Should not get here.");
+ return NULL;
+
+ case ir_type_assignment: {
+ ir_assignment *assign = ir->as_assignment();
+ ir_variable *assignee = assign->lhs->whole_variable_referenced();
+
+ if (assignee == var)
+ return (assign->condition != NULL) ? NULL : assign->rhs;
+
+ break;
+ }
+
+ default:
+ break;
+ }
+ }
+
+ return NULL;
+}
+
+
+static int
+calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment,
+ enum ir_expression_operation op)
+{
+ if (from == NULL || to == NULL || increment == NULL)
+ return -1;
+
+ void *mem_ctx = ralloc_context(NULL);
+
+ ir_expression *const sub =
+ new(mem_ctx) ir_expression(ir_binop_sub, from->type, to, from);
+
+ ir_expression *const div =
+ new(mem_ctx) ir_expression(ir_binop_div, sub->type, sub, increment);
+
+ ir_constant *iter = div->constant_expression_value(mem_ctx);
+ if (iter == NULL) {
+ ralloc_free(mem_ctx);
+ return -1;
+ }
+
+ if (!iter->type->is_integer()) {
+ const ir_expression_operation op = iter->type->is_double()
+ ? ir_unop_d2i : ir_unop_f2i;
+ ir_rvalue *cast =
+ new(mem_ctx) ir_expression(op, glsl_type::int_type, iter, NULL);
+
+ iter = cast->constant_expression_value(mem_ctx);
+ }
+
+ int iter_value = iter->get_int_component(0);
+
+ /* Make sure that the calculated number of iterations satisfies the exit
+ * condition. This is needed to catch off-by-one errors and some types of
+ * ill-formed loops. For example, we need to detect that the following
+ * loop does not have a maximum iteration count.
+ *
+ * for (float x = 0.0; x != 0.9; x += 0.2)
+ * ;
+ */
+ const int bias[] = { -1, 0, 1 };
+ bool valid_loop = false;
+
+ for (unsigned i = 0; i < ARRAY_SIZE(bias); i++) {
+ /* Increment may be of type int, uint or float. */
+ switch (increment->type->base_type) {
+ case GLSL_TYPE_INT:
+ iter = new(mem_ctx) ir_constant(iter_value + bias[i]);
+ break;
+ case GLSL_TYPE_UINT:
+ iter = new(mem_ctx) ir_constant(unsigned(iter_value + bias[i]));
+ break;
+ case GLSL_TYPE_FLOAT:
+ iter = new(mem_ctx) ir_constant(float(iter_value + bias[i]));
+ break;
+ case GLSL_TYPE_DOUBLE:
+ iter = new(mem_ctx) ir_constant(double(iter_value + bias[i]));
+ break;
+ default:
+ unreachable("Unsupported type for loop iterator.");
+ }
+
+ ir_expression *const mul =
+ new(mem_ctx) ir_expression(ir_binop_mul, increment->type, iter,
+ increment);
+
+ ir_expression *const add =
+ new(mem_ctx) ir_expression(ir_binop_add, mul->type, mul, from);
+
+ ir_expression *const cmp =
+ new(mem_ctx) ir_expression(op, glsl_type::bool_type, add, to);
+
+ ir_constant *const cmp_result = cmp->constant_expression_value(mem_ctx);
+
+ assert(cmp_result != NULL);
+ if (cmp_result->get_bool_component(0)) {
+ iter_value += bias[i];
+ valid_loop = true;
+ break;
+ }
+ }
+
+ ralloc_free(mem_ctx);
+ return (valid_loop) ? iter_value : -1;
+}
+
/**
* Record the fact that the given loop variable was referenced inside the loop.
diff --git a/src/compiler/glsl/loop_analysis.h b/src/compiler/glsl/loop_analysis.h
index 2894c6359be..e2eff9dbaed 100644
--- a/src/compiler/glsl/loop_analysis.h
+++ b/src/compiler/glsl/loop_analysis.h
@@ -55,13 +55,6 @@ extern bool
unroll_loops(exec_list *instructions, loop_state *ls,
const struct gl_shader_compiler_options *options);
-ir_rvalue *
-find_initial_value(ir_loop *loop, ir_variable *var);
-
-int
-calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment,
- enum ir_expression_operation op);
-
/**
* Tracking for all variables used in a loop
diff --git a/src/compiler/glsl/loop_controls.cpp b/src/compiler/glsl/loop_controls.cpp
index 895954fc2d1..ad4aa189411 100644
--- a/src/compiler/glsl/loop_controls.cpp
+++ b/src/compiler/glsl/loop_controls.cpp
@@ -27,145 +27,6 @@
#include "loop_analysis.h"
#include "ir_hierarchical_visitor.h"
-/**
- * Find an initializer of a variable outside a loop
- *
- * Works backwards from the loop to find the pre-loop value of the variable.
- * This is used, for example, to find the initial value of loop induction
- * variables.
- *
- * \param loop Loop where \c var is an induction variable
- * \param var Variable whose initializer is to be found
- *
- * \return
- * The \c ir_rvalue assigned to the variable outside the loop. May return
- * \c NULL if no initializer can be found.
- */
-ir_rvalue *
-find_initial_value(ir_loop *loop, ir_variable *var)
-{
- for (exec_node *node = loop->prev;
- !node->is_head_sentinel();
- node = node->prev) {
- ir_instruction *ir = (ir_instruction *) node;
-
- switch (ir->ir_type) {
- case ir_type_call:
- case ir_type_loop:
- case ir_type_loop_jump:
- case ir_type_return:
- case ir_type_if:
- return NULL;
-
- case ir_type_function:
- case ir_type_function_signature:
- assert(!"Should not get here.");
- return NULL;
-
- case ir_type_assignment: {
- ir_assignment *assign = ir->as_assignment();
- ir_variable *assignee = assign->lhs->whole_variable_referenced();
-
- if (assignee == var)
- return (assign->condition != NULL) ? NULL : assign->rhs;
-
- break;
- }
-
- default:
- break;
- }
- }
-
- return NULL;
-}
-
-
-int
-calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment,
- enum ir_expression_operation op)
-{
- if (from == NULL || to == NULL || increment == NULL)
- return -1;
-
- void *mem_ctx = ralloc_context(NULL);
-
- ir_expression *const sub =
- new(mem_ctx) ir_expression(ir_binop_sub, from->type, to, from);
-
- ir_expression *const div =
- new(mem_ctx) ir_expression(ir_binop_div, sub->type, sub, increment);
-
- ir_constant *iter = div->constant_expression_value(mem_ctx);
- if (iter == NULL) {
- ralloc_free(mem_ctx);
- return -1;
- }
-
- if (!iter->type->is_integer()) {
- const ir_expression_operation op = iter->type->is_double()
- ? ir_unop_d2i : ir_unop_f2i;
- ir_rvalue *cast =
- new(mem_ctx) ir_expression(op, glsl_type::int_type, iter, NULL);
-
- iter = cast->constant_expression_value(mem_ctx);
- }
-
- int iter_value = iter->get_int_component(0);
-
- /* Make sure that the calculated number of iterations satisfies the exit
- * condition. This is needed to catch off-by-one errors and some types of
- * ill-formed loops. For example, we need to detect that the following
- * loop does not have a maximum iteration count.
- *
- * for (float x = 0.0; x != 0.9; x += 0.2)
- * ;
- */
- const int bias[] = { -1, 0, 1 };
- bool valid_loop = false;
-
- for (unsigned i = 0; i < ARRAY_SIZE(bias); i++) {
- /* Increment may be of type int, uint or float. */
- switch (increment->type->base_type) {
- case GLSL_TYPE_INT:
- iter = new(mem_ctx) ir_constant(iter_value + bias[i]);
- break;
- case GLSL_TYPE_UINT:
- iter = new(mem_ctx) ir_constant(unsigned(iter_value + bias[i]));
- break;
- case GLSL_TYPE_FLOAT:
- iter = new(mem_ctx) ir_constant(float(iter_value + bias[i]));
- break;
- case GLSL_TYPE_DOUBLE:
- iter = new(mem_ctx) ir_constant(double(iter_value + bias[i]));
- break;
- default:
- unreachable("Unsupported type for loop iterator.");
- }
-
- ir_expression *const mul =
- new(mem_ctx) ir_expression(ir_binop_mul, increment->type, iter,
- increment);
-
- ir_expression *const add =
- new(mem_ctx) ir_expression(ir_binop_add, mul->type, mul, from);
-
- ir_expression *const cmp =
- new(mem_ctx) ir_expression(op, glsl_type::bool_type, add, to);
-
- ir_constant *const cmp_result = cmp->constant_expression_value(mem_ctx);
-
- assert(cmp_result != NULL);
- if (cmp_result->get_bool_component(0)) {
- iter_value += bias[i];
- valid_loop = true;
- break;
- }
- }
-
- ralloc_free(mem_ctx);
- return (valid_loop) ? iter_value : -1;
-}
namespace {
--
2.13.5
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