Allow optional sorting of profiler output via HL_PROFILER_SORT env var (

Fixes #7638)

src/runtime/profiler_common.cpp

@@ -333,6 +333,23 @@ WEAK void halide_profiler_memory_free(void *user_context,
 WEAK void halide_profiler_report_unlocked(void *user_context, halide_profiler_state *s) {
  StringStreamPrinter<1024> sstr(user_context);
 
+ int64_t (*compare_fs_fn)(halide_profiler_func_stats * a, halide_profiler_func_stats * b) = nullptr;
+
+ const char *sort_str = getenv("HL_PROFILER_SORT");
+ if (sort_str) {
+ if (!strcmp(sort_str, "time")) {
+ // Sort by descending time
+ compare_fs_fn = [](halide_profiler_func_stats *a, halide_profiler_func_stats *b) -> int64_t {
+ return (int64_t)b->time - (int64_t)a->time;
+ };
+ } else if (!strcmp(sort_str, "name")) {
+ // Sort by ascending name
+ compare_fs_fn = [](halide_profiler_func_stats *a, halide_profiler_func_stats *b) -> int64_t {
+ return strcmp(a->name, b->name);
+ };
+ }
+ }
+
  for (halide_profiler_pipeline_stats *p = s->pipelines; p;
  p = (halide_profiler_pipeline_stats *)(p->next)) {
  float t = p->time / 1000000.0f;
@@ -366,9 +383,9 @@ WEAK void halide_profiler_report_unlocked(void *user_context, halide_profiler_st
  }
 
  if (print_f_states) {
+ int f_stats_count = 0;
+ halide_profiler_func_stats **f_stats = (halide_profiler_func_stats **)__builtin_alloca(p->num_funcs * sizeof(halide_profiler_func_stats *));
  for (int i = 0; i < p->num_funcs; i++) {
- size_t cursor = 0;
- sstr.clear();
  halide_profiler_func_stats *fs = p->funcs + i;
 
  // The first func is always a catch-all overhead
@@ -377,6 +394,25 @@ WEAK void halide_profiler_report_unlocked(void *user_context, halide_profiler_st
  continue;
  }
 
+ f_stats[f_stats_count++] = fs;
+ }
+
+ if (compare_fs_fn) {
+ for (int i = 1; i < f_stats_count; i++) {
+ for (int j = i; j > 0 && compare_fs_fn(f_stats[j - 1], f_stats[j]) > 0; j--) {
+ auto *a = f_stats[j - 1];
+ auto *b = f_stats[j];
+ f_stats[j - 1] = b;
+ f_stats[j] = a;
+ }
+ }
+ }
+
+ for (int i = 0; i < f_stats_count; i++) {
+ size_t cursor = 0;
+ sstr.clear();
+ halide_profiler_func_stats *fs = f_stats[i];
+
  sstr << " " << fs->name << ": ";
  cursor += 25;
  while (sstr.size() < cursor) {