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-rw-r--r--tools/perf/util/block-range.c331
1 files changed, 331 insertions, 0 deletions
diff --git a/tools/perf/util/block-range.c b/tools/perf/util/block-range.c
new file mode 100644
index 000000000..1be432657
--- /dev/null
+++ b/tools/perf/util/block-range.c
@@ -0,0 +1,331 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "block-range.h"
+#include "annotate.h"
+#include <assert.h>
+#include <stdlib.h>
+
+struct {
+ struct rb_root root;
+ u64 blocks;
+} block_ranges;
+
+static void block_range__debug(void)
+{
+ /*
+ * XXX still paranoid for now; see if we can make this depend on
+ * DEBUG=1 builds.
+ */
+#if 1
+ struct rb_node *rb;
+ u64 old = 0; /* NULL isn't executable */
+
+ for (rb = rb_first(&block_ranges.root); rb; rb = rb_next(rb)) {
+ struct block_range *entry = rb_entry(rb, struct block_range, node);
+
+ assert(old < entry->start);
+ assert(entry->start <= entry->end); /* single instruction block; jump to a jump */
+
+ old = entry->end;
+ }
+#endif
+}
+
+struct block_range *block_range__find(u64 addr)
+{
+ struct rb_node **p = &block_ranges.root.rb_node;
+ struct rb_node *parent = NULL;
+ struct block_range *entry;
+
+ while (*p != NULL) {
+ parent = *p;
+ entry = rb_entry(parent, struct block_range, node);
+
+ if (addr < entry->start)
+ p = &parent->rb_left;
+ else if (addr > entry->end)
+ p = &parent->rb_right;
+ else
+ return entry;
+ }
+
+ return NULL;
+}
+
+static inline void rb_link_left_of_node(struct rb_node *left, struct rb_node *node)
+{
+ struct rb_node **p = &node->rb_left;
+ while (*p) {
+ node = *p;
+ p = &node->rb_right;
+ }
+ rb_link_node(left, node, p);
+}
+
+static inline void rb_link_right_of_node(struct rb_node *right, struct rb_node *node)
+{
+ struct rb_node **p = &node->rb_right;
+ while (*p) {
+ node = *p;
+ p = &node->rb_left;
+ }
+ rb_link_node(right, node, p);
+}
+
+/**
+ * block_range__create
+ * @start: branch target starting this basic block
+ * @end: branch ending this basic block
+ *
+ * Create all the required block ranges to precisely span the given range.
+ */
+struct block_range_iter block_range__create(u64 start, u64 end)
+{
+ struct rb_node **p = &block_ranges.root.rb_node;
+ struct rb_node *n, *parent = NULL;
+ struct block_range *next, *entry = NULL;
+ struct block_range_iter iter = { NULL, NULL };
+
+ while (*p != NULL) {
+ parent = *p;
+ entry = rb_entry(parent, struct block_range, node);
+
+ if (start < entry->start)
+ p = &parent->rb_left;
+ else if (start > entry->end)
+ p = &parent->rb_right;
+ else
+ break;
+ }
+
+ /*
+ * Didn't find anything.. there's a hole at @start, however @end might
+ * be inside/behind the next range.
+ */
+ if (!*p) {
+ if (!entry) /* tree empty */
+ goto do_whole;
+
+ /*
+ * If the last node is before, advance one to find the next.
+ */
+ n = parent;
+ if (entry->end < start) {
+ n = rb_next(n);
+ if (!n)
+ goto do_whole;
+ }
+ next = rb_entry(n, struct block_range, node);
+
+ if (next->start <= end) { /* add head: [start...][n->start...] */
+ struct block_range *head = malloc(sizeof(struct block_range));
+ if (!head)
+ return iter;
+
+ *head = (struct block_range){
+ .start = start,
+ .end = next->start - 1,
+ .is_target = 1,
+ .is_branch = 0,
+ };
+
+ rb_link_left_of_node(&head->node, &next->node);
+ rb_insert_color(&head->node, &block_ranges.root);
+ block_range__debug();
+
+ iter.start = head;
+ goto do_tail;
+ }
+
+do_whole:
+ /*
+ * The whole [start..end] range is non-overlapping.
+ */
+ entry = malloc(sizeof(struct block_range));
+ if (!entry)
+ return iter;
+
+ *entry = (struct block_range){
+ .start = start,
+ .end = end,
+ .is_target = 1,
+ .is_branch = 1,
+ };
+
+ rb_link_node(&entry->node, parent, p);
+ rb_insert_color(&entry->node, &block_ranges.root);
+ block_range__debug();
+
+ iter.start = entry;
+ iter.end = entry;
+ goto done;
+ }
+
+ /*
+ * We found a range that overlapped with ours, split if needed.
+ */
+ if (entry->start < start) { /* split: [e->start...][start...] */
+ struct block_range *head = malloc(sizeof(struct block_range));
+ if (!head)
+ return iter;
+
+ *head = (struct block_range){
+ .start = entry->start,
+ .end = start - 1,
+ .is_target = entry->is_target,
+ .is_branch = 0,
+
+ .coverage = entry->coverage,
+ .entry = entry->entry,
+ };
+
+ entry->start = start;
+ entry->is_target = 1;
+ entry->entry = 0;
+
+ rb_link_left_of_node(&head->node, &entry->node);
+ rb_insert_color(&head->node, &block_ranges.root);
+ block_range__debug();
+
+ } else if (entry->start == start)
+ entry->is_target = 1;
+
+ iter.start = entry;
+
+do_tail:
+ /*
+ * At this point we've got: @iter.start = [@start...] but @end can still be
+ * inside or beyond it.
+ */
+ entry = iter.start;
+ for (;;) {
+ /*
+ * If @end is inside @entry, split.
+ */
+ if (end < entry->end) { /* split: [...end][...e->end] */
+ struct block_range *tail = malloc(sizeof(struct block_range));
+ if (!tail)
+ return iter;
+
+ *tail = (struct block_range){
+ .start = end + 1,
+ .end = entry->end,
+ .is_target = 0,
+ .is_branch = entry->is_branch,
+
+ .coverage = entry->coverage,
+ .taken = entry->taken,
+ .pred = entry->pred,
+ };
+
+ entry->end = end;
+ entry->is_branch = 1;
+ entry->taken = 0;
+ entry->pred = 0;
+
+ rb_link_right_of_node(&tail->node, &entry->node);
+ rb_insert_color(&tail->node, &block_ranges.root);
+ block_range__debug();
+
+ iter.end = entry;
+ goto done;
+ }
+
+ /*
+ * If @end matches @entry, done
+ */
+ if (end == entry->end) {
+ entry->is_branch = 1;
+ iter.end = entry;
+ goto done;
+ }
+
+ next = block_range__next(entry);
+ if (!next)
+ goto add_tail;
+
+ /*
+ * If @end is in beyond @entry but not inside @next, add tail.
+ */
+ if (end < next->start) { /* add tail: [...e->end][...end] */
+ struct block_range *tail;
+add_tail:
+ tail = malloc(sizeof(struct block_range));
+ if (!tail)
+ return iter;
+
+ *tail = (struct block_range){
+ .start = entry->end + 1,
+ .end = end,
+ .is_target = 0,
+ .is_branch = 1,
+ };
+
+ rb_link_right_of_node(&tail->node, &entry->node);
+ rb_insert_color(&tail->node, &block_ranges.root);
+ block_range__debug();
+
+ iter.end = tail;
+ goto done;
+ }
+
+ /*
+ * If there is a hole between @entry and @next, fill it.
+ */
+ if (entry->end + 1 != next->start) {
+ struct block_range *hole = malloc(sizeof(struct block_range));
+ if (!hole)
+ return iter;
+
+ *hole = (struct block_range){
+ .start = entry->end + 1,
+ .end = next->start - 1,
+ .is_target = 0,
+ .is_branch = 0,
+ };
+
+ rb_link_left_of_node(&hole->node, &next->node);
+ rb_insert_color(&hole->node, &block_ranges.root);
+ block_range__debug();
+ }
+
+ entry = next;
+ }
+
+done:
+ assert(iter.start->start == start && iter.start->is_target);
+ assert(iter.end->end == end && iter.end->is_branch);
+
+ block_ranges.blocks++;
+
+ return iter;
+}
+
+
+/*
+ * Compute coverage as:
+ *
+ * br->coverage / br->sym->max_coverage
+ *
+ * This ensures each symbol has a 100% spot, to reflect that each symbol has a
+ * most covered section.
+ *
+ * Returns [0-1] for coverage and -1 if we had no data what so ever or the
+ * symbol does not exist.
+ */
+double block_range__coverage(struct block_range *br)
+{
+ struct symbol *sym;
+
+ if (!br) {
+ if (block_ranges.blocks)
+ return 0;
+
+ return -1;
+ }
+
+ sym = br->sym;
+ if (!sym)
+ return -1;
+
+ return (double)br->coverage / symbol__annotation(sym)->max_coverage;
+}