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| author | Jan Hubicka <jh@suse.cz> | 2020-10-26 18:19:48 +0100 |
|---|---|---|
| committer | Jan Hubicka <jh@suse.cz> | 2020-10-26 18:19:48 +0100 |
| commit | f20a6c57f0f26d9c60d6d6182f1e2181f727c834 (patch) | |
| tree | 27c496c30e568070afa9a437c707bd911b31db10 /gcc/predict.h | |
| parent | 63b2149fb4b0bd16c44ab9485cfdc37149e97b97 (diff) | |
| download | gcc-f20a6c57f0f26d9c60d6d6182f1e2181f727c834.zip gcc-f20a6c57f0f26d9c60d6d6182f1e2181f727c834.tar.gz gcc-f20a6c57f0f26d9c60d6d6182f1e2181f727c834.tar.bz2 | |
Implement three-level optimize_for_size predicates
this patch implements thre two-state optimize_for_size predicates, so with -Os
and with profile feedback for never executed code it returns OPTIMIZE_SIZE_MAX
while in cases we decide to optimize for size based on branch prediction logic
it return OPTIMIZE_SIZE_BALLANCED.
The idea is that for places where we guess that code is unlikely we do not
want to do extreme optimizations for size that leads to many fold slowdowns
(using idiv rather than few shigts or using rep based inlined stringops).
I will update RTL handling code to also support this with BB granuality (which
we don't currently). LLVM has -Os and -Oz levels where -Oz is our -Os and
LLVM's -Os would ocrrespond to OPTIMIZE_SIZE_BALLANCED. I wonder if we want
to export this to command line somehow? For me it would be definitly useful
to test things, I am not sure how "weaker" -Os is desired in practice.
gcc/ChangeLog:
* cgraph.h (cgraph_node::optimize_for_size_p): Return
optimize_size_level.
(cgraph_node::optimize_for_size_p): Update.
* coretypes.h (enum optimize_size_level): New enum.
* predict.c (unlikely_executed_edge_p): Microoptimize.
(optimize_function_for_size_p): Return optimize_size_level.
(optimize_bb_for_size_p): Likewise.
(optimize_edge_for_size_p): Likewise.
(optimize_insn_for_size_p): Likewise.
(optimize_loop_nest_for_size_p): Likewise.
* predict.h (optimize_function_for_size_p): Update declaration.
(optimize_bb_for_size_p): Update declaration.
(optimize_edge_for_size_p): Update declaration.
(optimize_insn_for_size_p): Update declaration.
(optimize_loop_for_size_p): Update declaration.
(optimize_loop_nest_for_size_p): Update declaration.
Diffstat (limited to 'gcc/predict.h')
| -rw-r--r-- | gcc/predict.h | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/gcc/predict.h b/gcc/predict.h index 274597e..b64d209 100644 --- a/gcc/predict.h +++ b/gcc/predict.h @@ -58,20 +58,20 @@ extern bool maybe_hot_bb_p (struct function *, const_basic_block); extern bool maybe_hot_edge_p (edge); extern bool probably_never_executed_bb_p (struct function *, const_basic_block); extern bool probably_never_executed_edge_p (struct function *, edge); -extern bool optimize_function_for_size_p (struct function *); +extern enum optimize_size_level optimize_function_for_size_p (struct function *); extern bool optimize_function_for_speed_p (struct function *); extern optimization_type function_optimization_type (struct function *); -extern bool optimize_bb_for_size_p (const_basic_block); +extern enum optimize_size_level optimize_bb_for_size_p (const_basic_block); extern bool optimize_bb_for_speed_p (const_basic_block); extern optimization_type bb_optimization_type (const_basic_block); -extern bool optimize_edge_for_size_p (edge); +extern enum optimize_size_level optimize_edge_for_size_p (edge); extern bool optimize_edge_for_speed_p (edge); -extern bool optimize_insn_for_size_p (void); +extern enum optimize_size_level optimize_insn_for_size_p (void); extern bool optimize_insn_for_speed_p (void); -extern bool optimize_loop_for_size_p (class loop *); +extern enum optimize_size_level optimize_loop_for_size_p (class loop *); extern bool optimize_loop_for_speed_p (class loop *); extern bool optimize_loop_nest_for_speed_p (class loop *); -extern bool optimize_loop_nest_for_size_p (class loop *); +extern enum optimize_size_level optimize_loop_nest_for_size_p (class loop *); extern bool predictable_edge_p (edge); extern void rtl_profile_for_bb (basic_block); extern void rtl_profile_for_edge (edge); |