// 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)
{
#ifndef NDEBUG
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;
}