Module: Mesa
Branch: main
Commit: debddca1344435d3b30cb86e5a9d4f3b79a378f8
URL:
http://cgit.freedesktop.org/mesa/mesa/commit/?id=debddca1344435d3b30cb86e5a9d4f3b79a378f8
Author: Rhys Perry <pendingchao...@gmail.com>
Date: Mon Jul 17 17:49:04 2023 +0100
nir: add helpers to skip idempotent passes
For example, in the loop:
while (more_late_algebraic) {
more_late_algebraic = false;
NIR_PASS(more_late_algebraic, nir, nir_opt_algebraic_late);
NIR_PASS(_, nir, nir_opt_constant_folding);
NIR_PASS(_, nir, nir_copy_prop);
NIR_PASS(_, nir, nir_opt_dce);
NIR_PASS(_, nir, nir_opt_cse);
}
if nir_opt_algebraic_late makes no progress, later passes might be
skippable depending on which ones made progress in the previous iteration.
Signed-off-by: Rhys Perry <pendingchao...@gmail.com>
Reviewed-by: Bas Nieuwenhuizen <b...@basnieuwenhuizen.nl>
Reviewed-by: Daniel Schürmann <dan...@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/24197>
---
src/compiler/nir/nir.h | 45 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 45 insertions(+)
diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h
index 365c47893fa..9df515f1342 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -4883,6 +4883,51 @@ should_print_nir(UNUSED nir_shader *shader)
nir_print_shader(nir, stdout); \
})
+#define _NIR_LOOP_PASS(progress, idempotent, skip, nir, pass, ...) \
+do { \
+ bool nir_loop_pass_progress = false; \
+ if (!_mesa_set_search(skip, (void (*)())&pass)) \
+ NIR_PASS(nir_loop_pass_progress, nir, pass, ##__VA_ARGS__); \
+ if (nir_loop_pass_progress) \
+ _mesa_set_clear(skip, NULL); \
+ if (idempotent || !nir_loop_pass_progress) \
+ _mesa_set_add(skip, (void (*)())&pass); \
+ UNUSED bool _ = false; \
+ progress |= nir_loop_pass_progress; \
+} while (0)
+
+/* Helper to skip a pass if no different passes have made progress since it was
+ * previously run. Note that two passes are considered the same if they have
+ * the same function pointer, even if they used different options.
+ *
+ * The usage of this is mostly identical to NIR_PASS. "skip" is a "struct set
*"
+ * (created by _mesa_pointer_set_create) which the macro uses to keep track of
+ * already run passes.
+ *
+ * Example:
+ * bool progress = true;
+ * struct set *skip = _mesa_pointer_set_create(NULL);
+ * while (progress) {
+ * progress = false;
+ * NIR_LOOP_PASS(progress, skip, nir, pass1);
+ * NIR_LOOP_PASS_NOT_IDEMPOTENT(progress, skip, nir, nir_opt_algebraic);
+ * NIR_LOOP_PASS(progress, skip, nir, pass2);
+ * ...
+ * }
+ * _mesa_set_destroy(skip, NULL);
+ *
+ * You shouldn't mix usage of this with the NIR_PASS set of helpers, without
+ * using a new "skip" in-between.
+ */
+#define NIR_LOOP_PASS(progress, skip, nir, pass, ...) \
+ _NIR_LOOP_PASS(progress, true, skip, nir, pass, ##__VA_ARGS__)
+
+/* Like NIR_LOOP_PASS, but use this for passes which may make further progress
+ * when repeated.
+ */
+#define NIR_LOOP_PASS_NOT_IDEMPOTENT(progress, skip, nir, pass, ...) \
+ _NIR_LOOP_PASS(progress, false, skip, nir, pass, ##__VA_ARGS__)
+
#define NIR_SKIP(name) should_skip_nir(#name)
/** An instruction filtering callback with writemask
