diff options
| author | Segher Boessenkool <segher@kernel.crashing.org> | 2015-10-01 08:38:24 +0200 |
|---|---|---|
| committer | Segher Boessenkool <segher@gcc.gnu.org> | 2015-10-01 08:38:24 +0200 |
| commit | 59faab7cc48681d8b2c995bdc466e1f3262839fa (patch) | |
| tree | a8576e110feff8492232a921cc8f8c525d14265c /gcc | |
| parent | 248c16c49ac74146a3b21f7536ede9b0f4378493 (diff) | |
| download | gcc-59faab7cc48681d8b2c995bdc466e1f3262839fa.zip gcc-59faab7cc48681d8b2c995bdc466e1f3262839fa.tar.gz gcc-59faab7cc48681d8b2c995bdc466e1f3262839fa.tar.bz2 | |
bb-reorder: Add -freorder-blocks-algorithm= and wire it up
This adds an -freorder-blocks-algorithm=[simple|stc] flag, with "simple"
as default. For -O2 and up (except -Os) it is switched to "stc" instead.
Targets that never want STC can override this. This changes -freorder-blocks
to be on at -O1 and up (was -O2 and up).
In effect, the changes are for -O1 (which now gets "simple" instead of
nothing), -Os (which now gets "simple" instead of "stc", since STC results
in much bigger code), and for targets that wish to never use STC (not in
this patch though).
2015-09-23 Segher Boessenkool <segher@kernel.crashing.org>
* bb-reorder.c (reorder_basic_blocks): Use the algorithm selected
with flag_reorder_blocks_algorithm.
* common.opt (freorder-blocks-algorithm=): New flag.
(reorder_blocks_algorithm): New enum.
* flag-types.h (reorder_blocks_algorithm): New enum.
* opts.c (default_options_table): Use -freorder-blocks at -O1 and up,
and -freorder-blocks-algorithm=stc at -O2 and up (not at -Os).
From-SVN: r228318
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 10 | ||||
| -rw-r--r-- | gcc/bb-reorder.c | 17 | ||||
| -rw-r--r-- | gcc/common.opt | 13 | ||||
| -rw-r--r-- | gcc/flag-types.h | 7 | ||||
| -rw-r--r-- | gcc/opts.c | 4 |
5 files changed, 46 insertions, 5 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 92fcb0f..8bfff2b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,15 @@ 2015-10-01 Segher Boessenkool <segher@kernel.crashing.org> + * bb-reorder.c (reorder_basic_blocks): Use the algorithm selected + with flag_reorder_blocks_algorithm. + * common.opt (freorder-blocks-algorithm=): New flag. + (reorder_blocks_algorithm): New enum. + * flag-types.h (reorder_blocks_algorithm): New enum. + * opts.c (default_options_table): Use -freorder-blocks at -O1 and up, + and -freorder-blocks-algorithm=stc at -O2 and up (not at -Os). + +2015-10-01 Segher Boessenkool <segher@kernel.crashing.org> + * bb-reorder.c: Add intro comment. (reorder_basic_blocks_software_trace_cache): Print a header to the dump file. diff --git a/gcc/bb-reorder.c b/gcc/bb-reorder.c index 4d07b2e..cb001e8 100644 --- a/gcc/bb-reorder.c +++ b/gcc/bb-reorder.c @@ -2444,10 +2444,19 @@ reorder_basic_blocks (void) set_edge_can_fallthru_flag (); mark_dfs_back_edges (); - if (1) - reorder_basic_blocks_software_trace_cache (); - else - reorder_basic_blocks_simple (); + switch (flag_reorder_blocks_algorithm) + { + case REORDER_BLOCKS_ALGORITHM_SIMPLE: + reorder_basic_blocks_simple (); + break; + + case REORDER_BLOCKS_ALGORITHM_STC: + reorder_basic_blocks_software_trace_cache (); + break; + + default: + gcc_unreachable (); + } relink_block_chain (/*stay_in_cfglayout_mode=*/true); diff --git a/gcc/common.opt b/gcc/common.opt index 94d1d88..b0f70fb 100644 --- a/gcc/common.opt +++ b/gcc/common.opt @@ -1910,6 +1910,19 @@ freorder-blocks Common Report Var(flag_reorder_blocks) Optimization Reorder basic blocks to improve code placement +freorder-blocks-algorithm= +Common Joined RejectNegative Enum(reorder_blocks_algorithm) Var(flag_reorder_blocks_algorithm) Init(REORDER_BLOCKS_ALGORITHM_SIMPLE) Optimization +-freorder-blocks-algorithm=[simple|stc] Set the used basic block reordering algorithm + +Enum +Name(reorder_blocks_algorithm) Type(enum reorder_blocks_algorithm) UnknownError(unknown basic block reordering algorithm %qs) + +EnumValue +Enum(reorder_blocks_algorithm) String(simple) Value(REORDER_BLOCKS_ALGORITHM_SIMPLE) + +EnumValue +Enum(reorder_blocks_algorithm) String(stc) Value(REORDER_BLOCKS_ALGORITHM_STC) + freorder-blocks-and-partition Common Report Var(flag_reorder_blocks_and_partition) Optimization Reorder basic blocks and partition into hot and cold sections diff --git a/gcc/flag-types.h b/gcc/flag-types.h index ac9ca0b..6301cea 100644 --- a/gcc/flag-types.h +++ b/gcc/flag-types.h @@ -109,6 +109,13 @@ enum stack_reuse_level SR_ALL }; +/* The algorithm used for basic block reordering. */ +enum reorder_blocks_algorithm +{ + REORDER_BLOCKS_ALGORITHM_SIMPLE, + REORDER_BLOCKS_ALGORITHM_STC +}; + /* The algorithm used for the integrated register allocator (IRA). */ enum ira_algorithm { @@ -441,6 +441,7 @@ static const struct default_options default_options_table[] = { OPT_LEVELS_1_PLUS, OPT_fipa_reference, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fipa_profile, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fmerge_constants, NULL, 1 }, + { OPT_LEVELS_1_PLUS, OPT_freorder_blocks, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fshrink_wrap, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_fsplit_wide_types, NULL, 1 }, { OPT_LEVELS_1_PLUS, OPT_ftree_ccp, NULL, 1 }, @@ -483,7 +484,8 @@ static const struct default_options default_options_table[] = #endif { OPT_LEVELS_2_PLUS, OPT_fstrict_aliasing, NULL, 1 }, { OPT_LEVELS_2_PLUS, OPT_fstrict_overflow, NULL, 1 }, - { OPT_LEVELS_2_PLUS, OPT_freorder_blocks, NULL, 1 }, + { OPT_LEVELS_2_PLUS_SPEED_ONLY, OPT_freorder_blocks_algorithm_, NULL, + REORDER_BLOCKS_ALGORITHM_STC }, { OPT_LEVELS_2_PLUS, OPT_freorder_functions, NULL, 1 }, { OPT_LEVELS_2_PLUS, OPT_ftree_vrp, NULL, 1 }, { OPT_LEVELS_2_PLUS, OPT_ftree_builtin_call_dce, NULL, 1 }, |