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Re: Fix PR 53743 and other -freorder-blocks-and-partition failures (issue6823047)
Yes, I have configured GCC with:
--target=arm-none-linux-gnueabi--with-cpu=cortex-a9 --with-fpu=neon
--with-float=softfp
Thanks,
Christophe.
On 28 November 2012 16:56, Teresa Johnson <tejohnson@google.com> wrote:
> Is this with the same target compiler and options used in PR55121? I
> will try to reproduce the compile-time failures with arm and those
> options if so. I haven't seen those with spec2006 linux x86_64. I'm
> not sure how to test the runtime behavior though.
>
> Thanks,
> Teresa
>
> On Wed, Nov 28, 2012 at 7:48 AM, Christophe Lyon
> <christophe.lyon@linaro.org> wrote:
>> I have updated my trunk checkout, and I can confirm that eval.c now
>> compiles with your patch (and the other 4 patches I added to PR55121).
>>
>> Now, when looking at the whole Spec2k results:
>> - vpr passes now (used to fail)
>> - gcc, parser, perlbmk bzip2 and twolf no longer build: they all fail
>> with the same error from gas:
>> can't resolve `.text.unlikely' {.text.unlikely section} - `.LBB171'
>> {.text section}
>> - gap still does not build (same error as above)
>>
>> I haven't looked in detail, so I may be missing an obvious patch here.
>>
>> And I still observe runtime mis-behaviour on crafty, galgel, facerec and fma3d.
>>
>> Thanks
>> Christophe.
>>
>>
>> On 26 November 2012 21:52, Teresa Johnson <tejohnson@google.com> wrote:
>>> Sorry, I don't know what happened there. Patch is attached.
>>> Thanks,
>>> Teresa
>>>
>>> On Mon, Nov 26, 2012 at 12:42 PM, Jack Howarth <howarth@bromo.med.uc.edu> wrote:
>>>> On Mon, Nov 26, 2012 at 12:19:55PM -0800, Teresa Johnson wrote:
>>>>> Are you sure you have all my changes applied? I applied the 4 patches
>>>>> attached to PR55121 into my trunk checkout that has my fixes, and to a
>>>>> pristine trunk checkout. I configured and built both for
>>>>> --target=arm-none-linux-gnueabi, and built using your options, .i file
>>>>> and gcda file. I can reproduce the failure using the pristine trunk
>>>>> with your patches but not with my fixed trunk + your patches. (I just
>>>>> updated to head to pickup recent changes and get the same result. The
>>>>> vec changes required some manual changes to the patch, which I will
>>>>> resend shortly.)
>>>>
>>>> Teresa,
>>>> Your mailer seems to have corrupted the posted patch with stray
>>>> =3D characters and line breaks. Can you repost a copy as an attachment
>>>> to the list?
>>>> Jack
>>>>
>>>>>
>>>>> Without my fixes:
>>>>>
>>>>> $ ~/extra/gcc_trunk_3_arm-eabi/gcc/cc1 -fpreproce
>>>>> ssed eval.i -quiet -dumpbase eval.c -march=armv7-a -mtune=cortex-a9
>>>>> -mthumb -mfpu=neon -mvectorize-with-neon-quad -mfloat-abi=softfp
>>>>> -mtls-dialect=gnu -auxbase-strip eval.o -g -O3 -version -fprofile-use
>>>>> -fno-common -o eval.s -freorder-blocks-and-partition
>>>>> GNU C (GCC) version 4.8.0 20121126 (experimental) (arm-none-linux-gnueabi)
>>>>> compiled by GNU C version 4.4.3, GMP version 4.3.2, MPFR version
>>>>> 2.4.2-p1, MPC version 0.8.1
>>>>> GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
>>>>> GNU C (GCC) version 4.8.0 20121126 (experimental) (arm-none-linux-gnueabi)
>>>>> compiled by GNU C version 4.4.3, GMP version 4.3.2, MPFR version
>>>>> 2.4.2-p1, MPC version 0.8.1
>>>>> GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
>>>>> Compiler executable checksum: d19cc60a2f07de08237a8488bb35cd1a
>>>>> eval.c: In function ‘Ge’:
>>>>> eval.c:792:1: internal compiler error: in df_compact_blocks, at df-core.c:1560
>>>>> }
>>>>> ^
>>>>> 0x622f71 df_compact_blocks()
>>>>> ../../gcc_trunk_3/gcc/df-core.c:1560
>>>>> 0x5cfcb5 compact_blocks()
>>>>> ../../gcc_trunk_3/gcc/cfg.c:162
>>>>> 0xc9dce0 reorder_basic_blocks
>>>>> ../../gcc_trunk_3/gcc/bb-reorder.c:2154
>>>>> 0xc9dce0 rest_of_handle_reorder_blocks
>>>>> ../../gcc_trunk_3/gcc/bb-reorder.c:2219
>>>>> Please submit a full bug report,
>>>>> with preprocessed source if appropriate.
>>>>> Please include the complete backtrace with any bug report.
>>>>> See <http://gcc.gnu.org/bugs.html> for instructions.
>>>>>
>>>>>
>>>>> With my fixes:
>>>>>
>>>>> $ ~/extra/gcc_trunk_4_arm-eabi/gcc/cc1 -fpreproce
>>>>> ssed eval.i -quiet -dumpbase eval.c -march=armv7-a -mtune=cortex-a9
>>>>> -mthumb -mfpu=neon -mvectorize-with-neon-quad -mfloat-abi=softfp
>>>>> -mtls-dialect=gnu -auxbase-strip eval.o -g -O3 -version -fprofile-use
>>>>> -fno-common -o eval.s -freorder-blocks-and-partition
>>>>> GNU C (GCC) version 4.8.0 20121126 (experimental) (arm-none-linux-gnueabi)
>>>>> compiled by GNU C version 4.4.3, GMP version 4.3.2, MPFR version
>>>>> 2.4.2-p1, MPC version 0.8.1
>>>>> GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
>>>>> GNU C (GCC) version 4.8.0 20121126 (experimental) (arm-none-linux-gnueabi)
>>>>> compiled by GNU C version 4.4.3, GMP version 4.3.2, MPFR version
>>>>> 2.4.2-p1, MPC version 0.8.1
>>>>> GGC heuristics: --param ggc-min-expand=30 --param ggc-min-heapsize=4096
>>>>> Compiler executable checksum: 45b468efa7c981f9afb44c4dac2424f3
>>>>>
>>>>>
>>>>> Thanks,
>>>>> Teresa
>>>>>
>>>>> On Mon, Nov 26, 2012 at 8:25 AM, Christophe Lyon
>>>>> <christophe.lyon@linaro.org> wrote:
>>>>> > Hi,
>>>>> >
>>>>> > I have tested your patch on Spec2000 on ARM, and I can still see
>>>>> > several failures caused by:
>>>>> > "error: fallthru edge crosses section boundary", including the case
>>>>> > described in PR55121.
>>>>> >
>>>>> > On 26 November 2012 16:55, Teresa Johnson <tejohnson@google.com> wrote:
>>>>> >> Ping.
>>>>> >> Teresa
>>>>> >>
>>>>> >> On Thu, Nov 15, 2012 at 12:10 PM, Teresa Johnson <tejohnson@google.com> wrote:
>>>>> >>> Revised patch that fixes failures encountered when enabling
>>>>> >>> -freorder-blocks-and-partition, including the failure reported in PR 53743.
>>>>> >>>
>>>>> >>> This includes new verification code to ensure no cold blocks dominate hot
>>>>> >>> blocks contributed by Steven Bosscher.
>>>>> >>>
>>>>> >>> I attempted to make the handling of partition updates through the optimization
>>>>> >>> passes much more consistent, removing a number of partial fixes in the code
>>>>> >>> stream in the process. The code to fixup partitions (including the BB_PARTITION
>>>>> >>> assignement, region crossing jump notes, and switch text section notes) is
>>>>> >>> now handled in a few centralized locations. For example, inside
>>>>> >>> rtl_redirect_edge_and_branch and force_nonfallthru_and_redirect, so that callers
>>>>> >>> don't need to attempt the fixup themselves.
>>>>> >>>
>>>>> >>> For optimization passes that make adjustments to the cfg while in cfg layout
>>>>> >>> mode that are not easy to fix up incrementally, the new routine
>>>>> >>> fixup_partitions handles the cleanup globally. This does require calculation
>>>>> >>> of the dominance relation, however, as far as I can tell the routines which
>>>>> >>> now invoke this global fixup (try_optimize_cfg and commit_edge_insertions)
>>>>> >>> are invoked typically once (or a small number of times in the case of
>>>>> >>> try_optimize_cfg) per optimization pass. Additionally, I compared the
>>>>> >>> -ftime-report output for some large fdo compilations and saw only minimal
>>>>> >>> increases in the dominance computation times, which were only a tiny percent
>>>>> >>> of the overall compile time.
>>>>> >>>
>>>>> >>> Additionally, I added a flag to the rtl_data structure to indicate whether
>>>>> >>> any partitioning was actually performed, so that optimizations which were
>>>>> >>> conservatively disabled whenever the flag_reorder_blocks_and_partition
>>>>> >>> is enabled (e.g. try_crossjump_to_edge, part of connect_traces) can be less
>>>>> >>> conservative for functions where no partitions were formed (e.g. they are
>>>>> >>> completely hot).
>>>>> >>>
>>>>> >>> Bootstrapped and tested on x86_64-unknown-linux-gnu. Also tested with SPEC2006 int
>>>>> >>> benchmarks and internal google benchmarks using profile feedback and
>>>>> >>> -freorder-blocks-and-partition to get more coverage. Ok for trunk?
>>>>> >>>
>>>>> >>> Thanks,
>>>>> >>> Teresa
>>>>> >>>
>>>>> >>> 2012-11-14 Teresa Johnson <tejohnson@google.com>
>>>>> >>> Steven Bosscher <steven@gcc.gnu.org>
>>>>> >>>
>>>>> >>> * cfghooks.h (cfg_layout_finalize): New parameter.
>>>>> >>> * modulo-sched.c (rest_of_handle_sms): New cfg_layout_finalize
>>>>> >>> parameter.
>>>>> >>> * ifcvt.c (find_if_case_1): Replace BB_COPY_PARTITION with assert
>>>>> >>> as this is now done by redirect_edge_and_branch_force.
>>>>> >>> * function.c (thread_prologue_and_epilogue_insns): Insert new bb after
>>>>> >>> barriers, new cfg_layout_finalize parameter, and don't store exit
>>>>> >>> predecessor BB until after it is potentially split.
>>>>> >>> * function.h (struct rtl_data): New flag has_bb_partition.
>>>>> >>> * hw-doloop.c (reorder_loops): New cfg_layout_finalize parameter.
>>>>> >>> * cfgcleanup.c (try_crossjump_to_edge): Only skip optimization if
>>>>> >>> any blocks in function actually partitioned.
>>>>> >>> (try_optimize_cfg): If cfg changed, invoke fixup_partitions to clean
>>>>> >>> up partitioning.
>>>>> >>> * bb-reorder.c (connect_traces): Only look for partitions and skip
>>>>> >>> block copying if any blocks in function actually partitioned.
>>>>> >>> (emit_barrier_after_bb): Handle insertion in non-cfglayout mode.
>>>>> >>> (find_rarely_executed_basic_blocks_and_crossing_edges): Ensure
>>>>> >>> that no cold blocks dominate a hot block.
>>>>> >>> (fix_up_fall_thru_edges): Replace BB_COPY_PARTITION with assert
>>>>> >>> as this is now done by force_nonfallthru_and_redirect.
>>>>> >>> (add_reg_crossing_jump_notes): Handle the fact that some jumps may
>>>>> >>> already be marked with region crossing note.
>>>>> >>> (reorder_basic_blocks): Only need to verify partitions if any
>>>>> >>> blocks in function actually partitioned.
>>>>> >>> (insert_section_boundary_note): Only need to insert note if any
>>>>> >>> blocks in function actually partitioned.
>>>>> >>> (rest_of_handle_reorder_blocks): New cfg_layout_finalize
>>>>> >>> parameter, and remove call to insert_section_boundary_note as this
>>>>> >>> is now called via cfg_layout_finalize/fixup_reorder_chain.
>>>>> >>> (duplicate_computed_gotos): New cfg_layout_finalize
>>>>> >>> parameter.
>>>>> >>> (partition_hot_cold_basic_blocks): Set flag indicating function
>>>>> >>> has bb partitions.
>>>>> >>> * bb-reorder.h: Declare insert_section_boundary_note and
>>>>> >>> emit_barrier_after_bb, which are no longer static.
>>>>> >>> * basic-block.h: Declare new function fixup_partitions.
>>>>> >>> * cfgrtl.c (try_redirect_by_replacing_jump): Remove unnecessary
>>>>> >>> check for region crossing note.
>>>>> >>> (fixup_partition_crossing): New function.
>>>>> >>> (fixup_bb_partition): Ditto.
>>>>> >>> (rtl_redirect_edge_and_branch): Fixup partition boundaries.
>>>>> >>> (force_nonfallthru_and_redirect): Fixup partition boundaries,
>>>>> >>> remove old code that tried to do this. Emit barrier correctly
>>>>> >>> when we are in cfglayout mode.
>>>>> >>> (rtl_split_edge): Correctly fixup partition boundaries.
>>>>> >>> (commit_one_edge_insertion): Remove old code that tried to
>>>>> >>> fixup region crossing edge since this is now handled in
>>>>> >>> split_block, and set up insertion point correctly since
>>>>> >>> block may now end in a jump.
>>>>> >>> (commit_edge_insertions): Invoke fixup_partitions to sanitize partition
>>>>> >>> boundaries after optimizations that modify cfg and before trying to
>>>>> >>> verify the flow info.
>>>>> >>> (fixup_partitions): New function.
>>>>> >>> (rtl_verify_flow_info_1): Add verification that no cold bbs dominate
>>>>> >>> hot bbs.
>>>>> >>> (record_effective_endpoints): Remove region-crossing notes and set flag
>>>>> >>> indicating that they need to be reinserted on exit from cfglayout mode.
>>>>> >>> (outof_cfg_layout_mode): New cfg_layout_finalize parameter.
>>>>> >>> (fixup_reorder_chain): Call insert_section_boundary_note if necessary.
>>>>> >>> Remove old code that attempted to fixup region crossing note as
>>>>> >>> this is now handled in force_nonfallthru_and_redirect.
>>>>> >>> (duplicate_insn_chain): Don't duplicate switch section notes.
>>>>> >>> (cfg_layout_finalize): Pass new parameter to fixup_reorder_chain.
>>>>> >>> (rtl_can_remove_branch_p): Remove unnecessary check for region crossing
>>>>> >>> note.
>>>>> >>>
>>>>> >>> Index: cfghooks.h
>>>>> >>> ===================================================================
>>>>> >>> --- cfghooks.h (revision 193376)
>>>>> >>> +++ cfghooks.h (working copy)
>>>>> >>> @@ -204,7 +204,7 @@ extern void copy_bbs (basic_block *, unsigned, bas
>>>>> >>> void account_profile_record (struct profile_record *, int);
>>>>> >>>
>>>>> >>> extern void cfg_layout_initialize (unsigned int);
>>>>> >>> -extern void cfg_layout_finalize (void);
>>>>> >>> +extern void cfg_layout_finalize (bool);
>>>>> >>>
>>>>> >>> /* Hooks containers. */
>>>>> >>> extern struct cfg_hooks gimple_cfg_hooks;
>>>>> >>> @@ -218,4 +218,3 @@ extern void cfg_layout_rtl_register_cfg_hooks (voi
>>>>> >>> extern void gimple_register_cfg_hooks (void);
>>>>> >>> extern struct cfg_hooks get_cfg_hooks (void);
>>>>> >>> extern void set_cfg_hooks (struct cfg_hooks);
>>>>> >>> -
>>>>> >>> Index: modulo-sched.c
>>>>> >>> ===================================================================
>>>>> >>> --- modulo-sched.c (revision 193376)
>>>>> >>> +++ modulo-sched.c (working copy)
>>>>> >>> @@ -3354,7 +3354,7 @@ rest_of_handle_sms (void)
>>>>> >>> if (bb->next_bb != EXIT_BLOCK_PTR)
>>>>> >>> bb->aux = bb->next_bb;
>>>>> >>> free_dominance_info (CDI_DOMINATORS);
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (false);
>>>>> >>> #endif /* INSN_SCHEDULING */
>>>>> >>> return 0;
>>>>> >>> }
>>>>> >>> Index: ifcvt.c
>>>>> >>> ===================================================================
>>>>> >>> --- ifcvt.c (revision 193376)
>>>>> >>> +++ ifcvt.c (working copy)
>>>>> >>> @@ -3900,10 +3900,9 @@ find_if_case_1 (basic_block test_bb, edge then_edg
>>>>> >>> if (new_bb)
>>>>> >>> {
>>>>> >>> df_bb_replace (then_bb_index, new_bb);
>>>>> >>> - /* Since the fallthru edge was redirected from test_bb to new_bb,
>>>>> >>> - we need to ensure that new_bb is in the same partition as
>>>>> >>> - test bb (you can not fall through across section boundaries). */
>>>>> >>> - BB_COPY_PARTITION (new_bb, test_bb);
>>>>> >>> + /* This should have been done above via force_nonfallthru_and_redirect
>>>>> >>> + (possibly called from redirect_edge_and_branch_force). */
>>>>> >>> + gcc_assert (BB_PARTITION (new_bb) == BB_PARTITION (test_bb));
>>>>> >>> }
>>>>> >>>
>>>>> >>> num_true_changes++;
>>>>> >>> Index: function.c
>>>>> >>> ===================================================================
>>>>> >>> --- function.c (revision 193376)
>>>>> >>> +++ function.c (working copy)
>>>>> >>> @@ -6249,8 +6249,10 @@ thread_prologue_and_epilogue_insns (void)
>>>>> >>> break;
>>>>> >>> if (e)
>>>>> >>> {
>>>>> >>> - copy_bb = create_basic_block (NEXT_INSN (BB_END (e->src)),
>>>>> >>> - NULL_RTX, e->src);
>>>>> >>> + /* Make sure we insert after any barriers. */
>>>>> >>> + rtx end = get_last_bb_insn (e->src);
>>>>> >>> + copy_bb = create_basic_block (NEXT_INSN (end),
>>>>> >>> + NULL_RTX, e->src);
>>>>> >>> BB_COPY_PARTITION (copy_bb, e->src);
>>>>> >>> }
>>>>> >>> else
>>>>> >>> @@ -6475,7 +6477,7 @@ thread_prologue_and_epilogue_insns (void)
>>>>> >>> if (cur_bb->index >= NUM_FIXED_BLOCKS
>>>>> >>> && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
>>>>> >>> cur_bb->aux = cur_bb->next_bb;
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (false);
>>>>> >>> }
>>>>> >>>
>>>>> >>> epilogue_done:
>>>>> >>> @@ -6517,7 +6519,7 @@ epilogue_done:
>>>>> >>> basic_block simple_return_block_cold = NULL;
>>>>> >>> edge pending_edge_hot = NULL;
>>>>> >>> edge pending_edge_cold = NULL;
>>>>> >>> - basic_block exit_pred = EXIT_BLOCK_PTR->prev_bb;
>>>>> >>> + basic_block exit_pred;
>>>>> >>> int i;
>>>>> >>>
>>>>> >>> gcc_assert (entry_edge != orig_entry_edge);
>>>>> >>> @@ -6545,6 +6547,12 @@ epilogue_done:
>>>>> >>> else
>>>>> >>> pending_edge_cold = e;
>>>>> >>> }
>>>>> >>> +
>>>>> >>> + /* Save a pointer to the exit's predecessor BB for use in
>>>>> >>> + inserting new BBs at the end of the function. Do this
>>>>> >>> + after the call to split_block above which may split
>>>>> >>> + the original exit pred. */
>>>>> >>> + exit_pred = EXIT_BLOCK_PTR->prev_bb;
>>>>> >>>
>>>>> >>> FOR_EACH_VEC_ELT (edge, unconverted_simple_returns, i, e)
>>>>> >>> {
>>>>> >>> Index: function.h
>>>>> >>> ===================================================================
>>>>> >>> --- function.h (revision 193376)
>>>>> >>> +++ function.h (working copy)
>>>>> >>> @@ -459,6 +459,11 @@ struct GTY(()) rtl_data {
>>>>> >>> sched2) and is useful only if the port defines LEAF_REGISTERS. */
>>>>> >>> bool uses_only_leaf_regs;
>>>>> >>>
>>>>> >>> + /* Nonzero if the function being compiled has undergone hot/cold partitioning
>>>>> >>> + (under flag_reorder_blocks_and_partition) and has at least one cold
>>>>> >>> + block. */
>>>>> >>> + bool has_bb_partition;
>>>>> >>> +
>>>>> >>> /* Like regs_ever_live, but 1 if a reg is set or clobbered from an
>>>>> >>> asm. Unlike regs_ever_live, elements of this array corresponding
>>>>> >>> to eliminable regs (like the frame pointer) are set if an asm
>>>>> >>> Index: hw-doloop.c
>>>>> >>> ===================================================================
>>>>> >>> --- hw-doloop.c (revision 193376)
>>>>> >>> +++ hw-doloop.c (working copy)
>>>>> >>> @@ -547,7 +547,7 @@ reorder_loops (hwloop_info loops)
>>>>> >>> else
>>>>> >>> bb->aux = NULL;
>>>>> >>> }
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (false);
>>>>> >>> clear_aux_for_blocks ();
>>>>> >>> df_analyze ();
>>>>> >>> }
>>>>> >>> Index: cfgcleanup.c
>>>>> >>> ===================================================================
>>>>> >>> --- cfgcleanup.c (revision 193376)
>>>>> >>> +++ cfgcleanup.c (working copy)
>>>>> >>> @@ -1824,7 +1824,7 @@ try_crossjump_to_edge (int mode, edge e1, edge e2,
>>>>> >>> partition boundaries). See the comments at the top of
>>>>> >>> bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
>>>>> >>>
>>>>> >>> - if (flag_reorder_blocks_and_partition && reload_completed)
>>>>> >>> + if (crtl->has_bb_partition && reload_completed)
>>>>> >>> return false;
>>>>> >>>
>>>>> >>> /* Search backward through forwarder blocks. We don't need to worry
>>>>> >>> @@ -2767,10 +2767,21 @@ try_optimize_cfg (int mode)
>>>>> >>> df_analyze ();
>>>>> >>> }
>>>>> >>>
>>>>> >>> + if (changed)
>>>>> >>> + {
>>>>> >>> + /* Edge forwarding in particular can cause hot blocks previously
>>>>> >>> + reached by both hot and cold blocks to become dominated only
>>>>> >>> + by cold blocks. This will cause the verification below to fail,
>>>>> >>> + and lead to now cold code in the hot section. This is not easy
>>>>> >>> + to detect and fix during edge forwarding, and in some cases
>>>>> >>> + is only visible after newly unreachable blocks are deleted,
>>>>> >>> + which will be done in fixup_partitions. */
>>>>> >>> + fixup_partitions ();
>>>>> >>> +
>>>>> >>> #ifdef ENABLE_CHECKING
>>>>> >>> - if (changed)
>>>>> >>> - verify_flow_info ();
>>>>> >>> + verify_flow_info ();
>>>>> >>> #endif
>>>>> >>> + }
>>>>> >>>
>>>>> >>> changed_overall |= changed;
>>>>> >>> first_pass = false;
>>>>> >>> Index: bb-reorder.c
>>>>> >>> ===================================================================
>>>>> >>> --- bb-reorder.c (revision 193376)
>>>>> >>> +++ bb-reorder.c (working copy)
>>>>> >>> @@ -1054,7 +1054,7 @@ connect_traces (int n_traces, struct trace *traces
>>>>> >>> current_partition = BB_PARTITION (traces[0].first);
>>>>> >>> two_passes = false;
>>>>> >>>
>>>>> >>> - if (flag_reorder_blocks_and_partition)
>>>>> >>> + if (crtl->has_bb_partition)
>>>>> >>> for (i = 0; i < n_traces && !two_passes; i++)
>>>>> >>> if (BB_PARTITION (traces[0].first)
>>>>> >>> != BB_PARTITION (traces[i].first))
>>>>> >>> @@ -1263,7 +1263,7 @@ connect_traces (int n_traces, struct trace *traces
>>>>> >>> }
>>>>> >>> }
>>>>> >>>
>>>>> >>> - if (flag_reorder_blocks_and_partition)
>>>>> >>> + if (crtl->has_bb_partition)
>>>>> >>> try_copy = false;
>>>>> >>>
>>>>> >>> /* Copy tiny blocks always; copy larger blocks only when the
>>>>> >>> @@ -1381,13 +1381,14 @@ get_uncond_jump_length (void)
>>>>> >>> return length;
>>>>> >>> }
>>>>> >>>
>>>>> >>> -/* Emit a barrier into the footer of BB. */
>>>>> >>> +/* Emit a barrier after BB, into the footer if we are in CFGLAYOUT mode. */
>>>>> >>>
>>>>> >>> -static void
>>>>> >>> +void
>>>>> >>> emit_barrier_after_bb (basic_block bb)
>>>>> >>> {
>>>>> >>> rtx barrier = emit_barrier_after (BB_END (bb));
>>>>> >>> - BB_FOOTER (bb) = unlink_insn_chain (barrier, barrier);
>>>>> >>> + if (current_ir_type () == IR_RTL_CFGLAYOUT)
>>>>> >>> + BB_FOOTER (bb) = unlink_insn_chain (barrier, barrier);
>>>>> >>> }
>>>>> >>>
>>>>> >>> /* The landing pad OLD_LP, in block OLD_BB, has edges from both partitions.
>>>>> >>> @@ -1463,18 +1464,109 @@ find_rarely_executed_basic_blocks_and_crossing_edg
>>>>> >>> {
>>>>> >>> VEC(edge, heap) *crossing_edges = NULL;
>>>>> >>> basic_block bb;
>>>>> >>> - edge e;
>>>>> >>> - edge_iterator ei;
>>>>> >>> + edge e, e2;
>>>>> >>> + edge_iterator ei, ei2;
>>>>> >>> + unsigned int cold_bb_count = 0;
>>>>> >>> + VEC (basic_block, heap) *bbs_in_hot_partition = NULL;
>>>>> >>> + VEC (basic_block, heap) *bbs_newly_hot = NULL;
>>>>> >>>
>>>>> >>> /* Mark which partition (hot/cold) each basic block belongs in. */
>>>>> >>> FOR_EACH_BB (bb)
>>>>> >>> {
>>>>> >>> if (probably_never_executed_bb_p (cfun, bb))
>>>>> >>> - BB_SET_PARTITION (bb, BB_COLD_PARTITION);
>>>>> >>> + {
>>>>> >>> + BB_SET_PARTITION (bb, BB_COLD_PARTITION);
>>>>> >>> + cold_bb_count++;
>>>>> >>> + }
>>>>> >>> else
>>>>> >>> - BB_SET_PARTITION (bb, BB_HOT_PARTITION);
>>>>> >>> + {
>>>>> >>> + BB_SET_PARTITION (bb, BB_HOT_PARTITION);
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_hot_partition, bb);
>>>>> >>> + }
>>>>> >>> }
>>>>> >>>
>>>>> >>> + /* Ensure that no cold bbs dominate hot bbs. This could happen as a result of
>>>>> >>> + several different possibilities. One is that there are edge weight insanities
>>>>> >>> + due to optimization phases that do not properly update basic block profile
>>>>> >>> + counts. The second is that the entry of the function may not be hot, because
>>>>> >>> + it is entered fewer times than the number of profile training runs, but there
>>>>> >>> + is a loop inside the function that causes blocks within the function to be
>>>>> >>> + above the threshold for hotness. */
>>>>> >>> + if (cold_bb_count)
>>>>> >>> + {
>>>>> >>> + bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS);
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + calculate_dominance_info (CDI_DOMINATORS);
>>>>> >>> +
>>>>> >>> + /* Keep examining hot bbs until we have either checked them all, or
>>>>> >>> + re-marked all cold bbs hot. */
>>>>> >>> + while (! VEC_empty (basic_block, bbs_in_hot_partition)
>>>>> >>> + && cold_bb_count)
>>>>> >>> + {
>>>>> >>> + basic_block dom_bb;
>>>>> >>> +
>>>>> >>> + bb = VEC_pop (basic_block, bbs_in_hot_partition);
>>>>> >>> + dom_bb = get_immediate_dominator (CDI_DOMINATORS, bb);
>>>>> >>> +
>>>>> >>> + /* If bb's immediate dominator is also hot then it is ok. */
>>>>> >>> + if (BB_PARTITION (dom_bb) != BB_COLD_PARTITION)
>>>>> >>> + continue;
>>>>> >>> +
>>>>> >>> + /* We have a hot bb with an immediate dominator that is cold.
>>>>> >>> + The dominator needs to be re-marked to hot. */
>>>>> >>> + BB_SET_PARTITION (dom_bb, BB_HOT_PARTITION);
>>>>> >>> + cold_bb_count--;
>>>>> >>> +
>>>>> >>> + /* Now we need to examine newly-hot dom_bb to see if it is also
>>>>> >>> + dominated by a cold bb. */
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_hot_partition, dom_bb);
>>>>> >>> +
>>>>> >>> + /* We should also adjust any cold blocks that the newly-hot bb
>>>>> >>> + feeds and see if it makes sense to re-mark those as hot as
>>>>> >>> + well. */
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_newly_hot, dom_bb);
>>>>> >>> + while (! VEC_empty (basic_block, bbs_newly_hot))
>>>>> >>> + {
>>>>> >>> + basic_block new_hot_bb = VEC_pop (basic_block, bbs_newly_hot);
>>>>> >>> + /* Examine all successors of this newly-hot bb to see if they
>>>>> >>> + are cold and should be re-marked as hot. */
>>>>> >>> + FOR_EACH_EDGE (e, ei, new_hot_bb->succs)
>>>>> >>> + {
>>>>> >>> + bool any_cold_preds = false;
>>>>> >>> + basic_block succ = e->dest;
>>>>> >>> + if (BB_PARTITION (succ) != BB_COLD_PARTITION)
>>>>> >>> + continue;
>>>>> >>> + /* Does this block have any cold predecessors now? */
>>>>> >>> + FOR_EACH_EDGE (e2, ei2, succ->preds)
>>>>> >>> + {
>>>>> >>> + if (BB_PARTITION (e2->src) == BB_COLD_PARTITION)
>>>>> >>> + {
>>>>> >>> + any_cold_preds = true;
>>>>> >>> + break;
>>>>> >>> + }
>>>>> >>> + }
>>>>> >>> + if (any_cold_preds)
>>>>> >>> + continue;
>>>>> >>> +
>>>>> >>> + /* Here we have a successor of newly-hot bb that is cold
>>>>> >>> + but no longer has any cold precessessors. Since the original
>>>>> >>> + assignment of our newly-hot bb was incorrect, this successor's
>>>>> >>> + assignment as cold is also suspect. Go ahead and re-mark it
>>>>> >>> + as hot now too. Better heuristics may be in order here. */
>>>>> >>> + BB_SET_PARTITION (succ, BB_HOT_PARTITION);
>>>>> >>> + cold_bb_count--;
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_hot_partition, succ);
>>>>> >>> + /* Examine this successor as a newly-hot bb. */
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_newly_hot, succ);
>>>>> >>> + }
>>>>> >>> + }
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + free_dominance_info (CDI_DOMINATORS);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> /* The format of .gcc_except_table does not allow landing pads to
>>>>> >>> be in a different partition as the throw. Fix this by either
>>>>> >>> moving or duplicating the landing pads. */
>>>>> >>> @@ -1766,10 +1858,10 @@ fix_up_fall_thru_edges (void)
>>>>> >>> new_bb->aux = cur_bb->aux;
>>>>> >>> cur_bb->aux = new_bb;
>>>>> >>>
>>>>> >>> - /* Make sure new fall-through bb is in same
>>>>> >>> - partition as bb it's falling through from. */
>>>>> >>> + /* This is done by force_nonfallthru_and_redirect. */
>>>>> >>> + gcc_assert (BB_PARTITION (new_bb)
>>>>> >>> + == BB_PARTITION (cur_bb));
>>>>> >>>
>>>>> >>> - BB_COPY_PARTITION (new_bb, cur_bb);
>>>>> >>> single_succ_edge (new_bb)->flags |= EDGE_CROSSING;
>>>>> >>> }
>>>>> >>> else
>>>>> >>> @@ -2067,7 +2159,10 @@ add_reg_crossing_jump_notes (void)
>>>>> >>> FOR_EACH_BB (bb)
>>>>> >>> FOR_EACH_EDGE (e, ei, bb->succs)
>>>>> >>> if ((e->flags & EDGE_CROSSING)
>>>>> >>> - && JUMP_P (BB_END (e->src)))
>>>>> >>> + && JUMP_P (BB_END (e->src))
>>>>> >>> + /* Some notes were added during fix_up_fall_thru_edges, via
>>>>> >>> + force_nonfallthru_and_redirect. */
>>>>> >>> + && !find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX))
>>>>> >>> add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -2160,7 +2255,7 @@ reorder_basic_blocks (void)
>>>>> >>> dump_flow_info (dump_file, dump_flags);
>>>>> >>> }
>>>>> >>>
>>>>> >>> - if (flag_reorder_blocks_and_partition)
>>>>> >>> + if (crtl->has_bb_partition)
>>>>> >>> verify_hot_cold_block_grouping ();
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -2172,14 +2267,14 @@ reorder_basic_blocks (void)
>>>>> >>> encountering this note will make the compiler switch between the
>>>>> >>> hot and cold text sections. */
>>>>> >>>
>>>>> >>> -static void
>>>>> >>> +void
>>>>> >>> insert_section_boundary_note (void)
>>>>> >>> {
>>>>> >>> basic_block bb;
>>>>> >>> rtx new_note;
>>>>> >>> int first_partition = 0;
>>>>> >>>
>>>>> >>> - if (!flag_reorder_blocks_and_partition)
>>>>> >>> + if (!crtl->has_bb_partition)
>>>>> >>> return;
>>>>> >>>
>>>>> >>> FOR_EACH_BB (bb)
>>>>> >>> @@ -2222,10 +2317,8 @@ rest_of_handle_reorder_blocks (void)
>>>>> >>> FOR_EACH_BB (bb)
>>>>> >>> if (bb->next_bb != EXIT_BLOCK_PTR)
>>>>> >>> bb->aux = bb->next_bb;
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (true);
>>>>> >>>
>>>>> >>> - /* Add NOTE_INSN_SWITCH_TEXT_SECTIONS notes. */
>>>>> >>> - insert_section_boundary_note ();
>>>>> >>> return 0;
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -2366,7 +2459,7 @@ duplicate_computed_gotos (void)
>>>>> >>> }
>>>>> >>>
>>>>> >>> done:
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (false);
>>>>> >>>
>>>>> >>> BITMAP_FREE (candidates);
>>>>> >>> return 0;
>>>>> >>> @@ -2511,6 +2604,8 @@ partition_hot_cold_basic_blocks (void)
>>>>> >>> if (crossing_edges == NULL)
>>>>> >>> return 0;
>>>>> >>>
>>>>> >>> + crtl->has_bb_partition = true;
>>>>> >>> +
>>>>> >>> /* Make sure the source of any crossing edge ends in a jump and the
>>>>> >>> destination of any crossing edge has a label. */
>>>>> >>> add_labels_and_missing_jumps (crossing_edges);
>>>>> >>> Index: bb-reorder.h
>>>>> >>> ===================================================================
>>>>> >>> --- bb-reorder.h (revision 193376)
>>>>> >>> +++ bb-reorder.h (working copy)
>>>>> >>> @@ -36,4 +36,8 @@ extern struct target_bb_reorder *this_target_bb_re
>>>>> >>>
>>>>> >>> extern int get_uncond_jump_length (void);
>>>>> >>>
>>>>> >>> +extern void insert_section_boundary_note (void);
>>>>> >>> +
>>>>> >>> +extern void emit_barrier_after_bb (basic_block bb);
>>>>> >>> +
>>>>> >>> #endif
>>>>> >>> Index: basic-block.h
>>>>> >>> ===================================================================
>>>>> >>> --- basic-block.h (revision 193376)
>>>>> >>> +++ basic-block.h (working copy)
>>>>> >>> @@ -806,6 +806,7 @@ extern basic_block force_nonfallthru_and_redirect
>>>>> >>> extern bool contains_no_active_insn_p (const_basic_block);
>>>>> >>> extern bool forwarder_block_p (const_basic_block);
>>>>> >>> extern bool can_fallthru (basic_block, basic_block);
>>>>> >>> +extern void fixup_partitions (void);
>>>>> >>>
>>>>> >>> /* In cfgbuild.c. */
>>>>> >>> extern void find_many_sub_basic_blocks (sbitmap);
>>>>> >>> Index: cfgrtl.c
>>>>> >>> ===================================================================
>>>>> >>> --- cfgrtl.c (revision 193376)
>>>>> >>> +++ cfgrtl.c (working copy)
>>>>> >>> @@ -46,6 +46,7 @@ along with GCC; see the file COPYING3. If not see
>>>>> >>> #include "tree.h"
>>>>> >>> #include "hard-reg-set.h"
>>>>> >>> #include "basic-block.h"
>>>>> >>> +#include "bb-reorder.h"
>>>>> >>> #include "regs.h"
>>>>> >>> #include "flags.h"
>>>>> >>> #include "function.h"
>>>>> >>> @@ -67,11 +68,12 @@ along with GCC; see the file COPYING3. If not see
>>>>> >>> Only applicable if the CFG is in cfglayout mode. */
>>>>> >>> static GTY(()) rtx cfg_layout_function_footer;
>>>>> >>> static GTY(()) rtx cfg_layout_function_header;
>>>>> >>> +static bool had_sec_boundary_notes;
>>>>> >>>
>>>>> >>> static rtx skip_insns_after_block (basic_block);
>>>>> >>> static void record_effective_endpoints (void);
>>>>> >>> static rtx label_for_bb (basic_block);
>>>>> >>> -static void fixup_reorder_chain (void);
>>>>> >>> +static void fixup_reorder_chain (bool finalize_reorder_blocks);
>>>>> >>>
>>>>> >>> void verify_insn_chain (void);
>>>>> >>> static void fixup_fallthru_exit_predecessor (void);
>>>>> >>> @@ -976,8 +978,7 @@ try_redirect_by_replacing_jump (edge e, basic_bloc
>>>>> >>> partition boundaries). See the comments at the top of
>>>>> >>> bb-reorder.c:partition_hot_cold_basic_blocks for complete details. */
>>>>> >>>
>>>>> >>> - if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)
>>>>> >>> - || BB_PARTITION (src) != BB_PARTITION (target))
>>>>> >>> + if (BB_PARTITION (src) != BB_PARTITION (target))
>>>>> >>> return NULL;
>>>>> >>>
>>>>> >>> /* We can replace or remove a complex jump only when we have exactly
>>>>> >>> @@ -1286,6 +1287,71 @@ redirect_branch_edge (edge e, basic_block target)
>>>>> >>> return e;
>>>>> >>> }
>>>>> >>>
>>>>> >>> +/* Called when edge E has been redirected to a new destination,
>>>>> >>> + in order to update the region crossing flag on the edge and
>>>>> >>> + jump. */
>>>>> >>> +
>>>>> >>> +static void
>>>>> >>> +fixup_partition_crossing (edge e, basic_block target)
>>>>> >>> +{
>>>>> >>> + rtx note;
>>>>> >>> +
>>>>> >>> + gcc_assert (e->dest == target);
>>>>> >>> +
>>>>> >>> + if (e->src == ENTRY_BLOCK_PTR || target == EXIT_BLOCK_PTR)
>>>>> >>> + return;
>>>>> >>> + /* If we redirected an existing edge, it may already be marked
>>>>> >>> + crossing, even though the new src is missing a reg crossing note.
>>>>> >>> + But make sure reg crossing note doesn't already exist before
>>>>> >>> + inserting. */
>>>>> >>> + if (BB_PARTITION (e->src) != BB_PARTITION (target))
>>>>> >>> + {
>>>>> >>> + e->flags |= EDGE_CROSSING;
>>>>> >>> + note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> + if (JUMP_P (BB_END (e->src))
>>>>> >>> + && !note)
>>>>> >>> + add_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> + }
>>>>> >>> + else if (BB_PARTITION (e->src) == BB_PARTITION (target))
>>>>> >>> + {
>>>>> >>> + e->flags &= ~EDGE_CROSSING;
>>>>> >>> + /* Remove the region crossing note from jump at end of
>>>>> >>> + e->src if it exists. */
>>>>> >>> + note = find_reg_note (BB_END (e->src), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> + if (note)
>>>>> >>> + remove_note (BB_END (e->src), note);
>>>>> >>> + }
>>>>> >>> +}
>>>>> >>> +
>>>>> >>> +/* Called when block BB has been reassigned to a different partition,
>>>>> >>> + to ensure that the region crossing attributes are updated. */
>>>>> >>> +
>>>>> >>> +static void
>>>>> >>> +fixup_bb_partition (basic_block bb)
>>>>> >>> +{
>>>>> >>> + edge e;
>>>>> >>> + edge_iterator ei;
>>>>> >>> +
>>>>> >>> + /* Now need to make bb's pred edges non-region crossing. */
>>>>> >>> + FOR_EACH_EDGE (e, ei, bb->preds)
>>>>> >>> + {
>>>>> >>> + fixup_partition_crossing (e, e->dest);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> + /* Possibly need to make bb's successor edges region crossing,
>>>>> >>> + or remove stale region crossing. */
>>>>> >>> + FOR_EACH_EDGE (e, ei, bb->succs)
>>>>> >>> + {
>>>>> >>> + if ((e->flags & EDGE_FALLTHRU)
>>>>> >>> + && BB_PARTITION (bb) != BB_PARTITION (e->dest)
>>>>> >>> + && e->dest != EXIT_BLOCK_PTR)
>>>>> >>> + /* force_nonfallthru_and_redirect calls fixup_partition_crossing. */
>>>>> >>> + force_nonfallthru (e);
>>>>> >>> + else
>>>>> >>> + fixup_partition_crossing (e, e->dest);
>>>>> >>> + }
>>>>> >>> +}
>>>>> >>> +
>>>>> >>> /* Attempt to change code to redirect edge E to TARGET. Don't do that on
>>>>> >>> expense of adding new instructions or reordering basic blocks.
>>>>> >>>
>>>>> >>> @@ -1302,16 +1368,18 @@ rtl_redirect_edge_and_branch (edge e, basic_block
>>>>> >>> {
>>>>> >>> edge ret;
>>>>> >>> basic_block src = e->src;
>>>>> >>> + basic_block dest = e->dest;
>>>>> >>>
>>>>> >>> if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
>>>>> >>> return NULL;
>>>>> >>>
>>>>> >>> - if (e->dest == target)
>>>>> >>> + if (dest == target)
>>>>> >>> return e;
>>>>> >>>
>>>>> >>> if ((ret = try_redirect_by_replacing_jump (e, target, false)) != NULL)
>>>>> >>> {
>>>>> >>> df_set_bb_dirty (src);
>>>>> >>> + fixup_partition_crossing (ret, target);
>>>>> >>> return ret;
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -1320,6 +1388,7 @@ rtl_redirect_edge_and_branch (edge e, basic_block
>>>>> >>> return NULL;
>>>>> >>>
>>>>> >>> df_set_bb_dirty (src);
>>>>> >>> + fixup_partition_crossing (ret, target);
>>>>> >>> return ret;
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -1454,18 +1523,16 @@ force_nonfallthru_and_redirect (edge e, basic_bloc
>>>>> >>> /* Make sure new block ends up in correct hot/cold section. */
>>>>> >>>
>>>>> >>> BB_COPY_PARTITION (jump_block, e->src);
>>>>> >>> - if (flag_reorder_blocks_and_partition
>>>>> >>> - && targetm_common.have_named_sections
>>>>> >>> - && JUMP_P (BB_END (jump_block))
>>>>> >>> - && !any_condjump_p (BB_END (jump_block))
>>>>> >>> - && (EDGE_SUCC (jump_block, 0)->flags & EDGE_CROSSING))
>>>>> >>> - add_reg_note (BB_END (jump_block), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>>
>>>>> >>> /* Wire edge in. */
>>>>> >>> new_edge = make_edge (e->src, jump_block, EDGE_FALLTHRU);
>>>>> >>> new_edge->probability = probability;
>>>>> >>> new_edge->count = count;
>>>>> >>>
>>>>> >>> + /* If e->src was previously region crossing, it no longer is
>>>>> >>> + and the reg crossing note should be removed. */
>>>>> >>> + fixup_partition_crossing (new_edge, jump_block);
>>>>> >>> +
>>>>> >>> /* Redirect old edge. */
>>>>> >>> redirect_edge_pred (e, jump_block);
>>>>> >>> e->probability = REG_BR_PROB_BASE;
>>>>> >>> @@ -1521,13 +1588,16 @@ force_nonfallthru_and_redirect (edge e, basic_bloc
>>>>> >>> LABEL_NUSES (label)++;
>>>>> >>> }
>>>>> >>>
>>>>> >>> - emit_barrier_after (BB_END (jump_block));
>>>>> >>> + /* We might be in cfg layout mode, and if so, the following routine will
>>>>> >>> + insert the barrier correctly. */
>>>>> >>> + emit_barrier_after_bb (jump_block);
>>>>> >>> redirect_edge_succ_nodup (e, target);
>>>>> >>>
>>>>> >>> if (abnormal_edge_flags)
>>>>> >>> make_edge (src, target, abnormal_edge_flags);
>>>>> >>>
>>>>> >>> df_mark_solutions_dirty ();
>>>>> >>> + fixup_partition_crossing (e, target);
>>>>> >>> return new_bb;
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -1626,7 +1696,7 @@ rtl_move_block_after (basic_block bb ATTRIBUTE_UNU
>>>>> >>> static basic_block
>>>>> >>> rtl_split_edge (edge edge_in)
>>>>> >>> {
>>>>> >>> - basic_block bb;
>>>>> >>> + basic_block bb, new_bb;
>>>>> >>> rtx before;
>>>>> >>>
>>>>> >>> /* Abnormal edges cannot be split. */
>>>>> >>> @@ -1659,12 +1729,26 @@ rtl_split_edge (edge edge_in)
>>>>> >>> else
>>>>> >>> {
>>>>> >>> bb = create_basic_block (before, NULL, edge_in->dest->prev_bb);
>>>>> >>> - /* ??? Why not edge_in->dest->prev_bb here? */
>>>>> >>> - BB_COPY_PARTITION (bb, edge_in->dest);
>>>>> >>> + if (edge_in->src == ENTRY_BLOCK_PTR)
>>>>> >>> + BB_COPY_PARTITION (bb, edge_in->dest);
>>>>> >>> + else
>>>>> >>> + /* Put the split bb into the src partition, to avoid creating
>>>>> >>> + a situation where a cold bb dominates a hot bb, in the case
>>>>> >>> + where src is cold and dest is hot. The src will dominate
>>>>> >>> + the new bb (whereas it might not have dominated dest). */
>>>>> >>> + BB_COPY_PARTITION (bb, edge_in->src);
>>>>> >>> }
>>>>> >>>
>>>>> >>> make_single_succ_edge (bb, edge_in->dest, EDGE_FALLTHRU);
>>>>> >>>
>>>>> >>> + /* Can't allow a region crossing edge to be fallthrough. */
>>>>> >>> + if (BB_PARTITION (bb) != BB_PARTITION (edge_in->dest)
>>>>> >>> + && edge_in->dest != EXIT_BLOCK_PTR)
>>>>> >>> + {
>>>>> >>> + new_bb = force_nonfallthru (single_succ_edge (bb));
>>>>> >>> + gcc_assert (!new_bb);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> /* For non-fallthru edges, we must adjust the predecessor's
>>>>> >>> jump instruction to target our new block. */
>>>>> >>> if ((edge_in->flags & EDGE_FALLTHRU) == 0)
>>>>> >>> @@ -1777,17 +1861,13 @@ commit_one_edge_insertion (edge e)
>>>>> >>> else
>>>>> >>> {
>>>>> >>> bb = split_edge (e);
>>>>> >>> - after = BB_END (bb);
>>>>> >>>
>>>>> >>> - if (flag_reorder_blocks_and_partition
>>>>> >>> - && targetm_common.have_named_sections
>>>>> >>> - && e->src != ENTRY_BLOCK_PTR
>>>>> >>> - && BB_PARTITION (e->src) == BB_COLD_PARTITION
>>>>> >>> - && !(e->flags & EDGE_CROSSING)
>>>>> >>> - && JUMP_P (after)
>>>>> >>> - && !any_condjump_p (after)
>>>>> >>> - && (single_succ_edge (bb)->flags & EDGE_CROSSING))
>>>>> >>> - add_reg_note (after, REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> + /* If e crossed a partition boundary, we needed to make bb end in
>>>>> >>> + a region-crossing jump, even though it was originally fallthru. */
>>>>> >>> + if (JUMP_P (BB_END (bb)))
>>>>> >>> + before = BB_END (bb);
>>>>> >>> + else
>>>>> >>> + after = BB_END (bb);
>>>>> >>> }
>>>>> >>>
>>>>> >>> /* Now that we've found the spot, do the insertion. */
>>>>> >>> @@ -1827,6 +1907,14 @@ commit_edge_insertions (void)
>>>>> >>> {
>>>>> >>> basic_block bb;
>>>>> >>>
>>>>> >>> + /* Optimization passes that invoke this routine can cause hot blocks
>>>>> >>> + previously reached by both hot and cold blocks to become dominated only
>>>>> >>> + by cold blocks. This will cause the verification below to fail,
>>>>> >>> + and lead to now cold code in the hot section. In some cases this
>>>>> >>> + may only be visible after newly unreachable blocks are deleted,
>>>>> >>> + which will be done by fixup_partitions. */
>>>>> >>> + fixup_partitions ();
>>>>> >>> +
>>>>> >>> #ifdef ENABLE_CHECKING
>>>>> >>> verify_flow_info ();
>>>>> >>> #endif
>>>>> >>> @@ -2028,7 +2116,75 @@ get_last_bb_insn (basic_block bb)
>>>>> >>>
>>>>> >>> return end;
>>>>> >>> }
>>>>> >>> -
>>>>> >>> +
>>>>> >>> +/* Perform cleanup on the hot/cold bb partitioning after optimization
>>>>> >>> + passes that modify the cfg. */
>>>>> >>> +
>>>>> >>> +void
>>>>> >>> +fixup_partitions (void)
>>>>> >>> +{
>>>>> >>> + basic_block bb;
>>>>> >>> +
>>>>> >>> + if (!crtl->has_bb_partition)
>>>>> >>> + return;
>>>>> >>> +
>>>>> >>> + /* Delete any blocks that became unreachable and weren't
>>>>> >>> + already cleaned up, for example during edge forwarding
>>>>> >>> + and convert_jumps_to_returns. This will expose more
>>>>> >>> + opportunities for fixing the partition boundaries here.
>>>>> >>> + Also, the calculation of the dominance graph during verification
>>>>> >>> + will assert if there are unreachable nodes. */
>>>>> >>> + delete_unreachable_blocks ();
>>>>> >>> +
>>>>> >>> + /* If there are partitions, do a sanity check on them: A basic block in
>>>>> >>> + a cold partition cannot dominate a basic block in a hot partition.
>>>>> >>> + Fixup any that now violate this requirement, as a result of edge
>>>>> >>> + forwarding and unreachable block deletion. */
>>>>> >>> + VEC (basic_block, heap) *bbs_in_cold_partition = NULL;
>>>>> >>> + VEC (basic_block, heap) *bbs_to_fix = NULL;
>>>>> >>> + FOR_EACH_BB (bb)
>>>>> >>> + if ((BB_PARTITION (bb) == BB_COLD_PARTITION))
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_cold_partition, bb);
>>>>> >>> + if (! VEC_empty (basic_block, bbs_in_cold_partition))
>>>>> >>> + {
>>>>> >>> + bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS);
>>>>> >>> + basic_block son;
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + calculate_dominance_info (CDI_DOMINATORS);
>>>>> >>> +
>>>>> >>> + while (! VEC_empty (basic_block, bbs_in_cold_partition))
>>>>> >>> + {
>>>>> >>> + bb = VEC_pop (basic_block, bbs_in_cold_partition);
>>>>> >>> + /* If bb is not yet cold (because it was added below as
>>>>> >>> + a block dominated by a cold bb) then mark it cold here. */
>>>>> >>> + if ((BB_PARTITION (bb) != BB_COLD_PARTITION))
>>>>> >>> + {
>>>>> >>> + BB_SET_PARTITION (bb, BB_COLD_PARTITION);
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_to_fix, bb);
>>>>> >>> + }
>>>>> >>> + /* Any blocks dominated by a block in the cold section
>>>>> >>> + must also be cold. */
>>>>> >>> + for (son = first_dom_son (CDI_DOMINATORS, bb);
>>>>> >>> + son;
>>>>> >>> + son = next_dom_son (CDI_DOMINATORS, son))
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_cold_partition, son);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + free_dominance_info (CDI_DOMINATORS);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> + /* Do the partition fixup after all necessary blocks have been converted to
>>>>> >>> + cold, so that we only update the region crossings the minimum number of
>>>>> >>> + places, which can require forcing edges to be non fallthru. */
>>>>> >>> + while (! VEC_empty (basic_block, bbs_to_fix))
>>>>> >>> + {
>>>>> >>> + bb = VEC_pop (basic_block, bbs_to_fix);
>>>>> >>> + fixup_bb_partition (bb);
>>>>> >>> + }
>>>>> >>> +}
>>>>> >>> +
>>>>> >>> /* Verify the CFG and RTL consistency common for both underlying RTL and
>>>>> >>> cfglayout RTL.
>>>>> >>>
>>>>> >>> @@ -2052,6 +2208,7 @@ rtl_verify_flow_info_1 (void)
>>>>> >>> rtx x;
>>>>> >>> int err = 0;
>>>>> >>> basic_block bb;
>>>>> >>> + bool have_partitions = false;
>>>>> >>>
>>>>> >>> /* Check the general integrity of the basic blocks. */
>>>>> >>> FOR_EACH_BB_REVERSE (bb)
>>>>> >>> @@ -2169,6 +2326,8 @@ rtl_verify_flow_info_1 (void)
>>>>> >>>
>>>>> >>> if (e->flags & EDGE_ABNORMAL)
>>>>> >>> n_abnormal++;
>>>>> >>> +
>>>>> >>> + have_partitions |= is_crossing;
>>>>> >>> }
>>>>> >>>
>>>>> >>> if (n_eh && !find_reg_note (BB_END (bb), REG_EH_REGION, NULL_RTX))
>>>>> >>> @@ -2293,6 +2452,40 @@ rtl_verify_flow_info_1 (void)
>>>>> >>> }
>>>>> >>> }
>>>>> >>>
>>>>> >>> + /* If there are partitions, do a sanity check on them: A basic block in
>>>>> >>> + a cold partition cannot dominate a basic block in a hot partition. */
>>>>> >>> + VEC (basic_block, heap) *bbs_in_cold_partition = NULL;
>>>>> >>> + if (have_partitions && !err)
>>>>> >>> + FOR_EACH_BB (bb)
>>>>> >>> + if ((BB_PARTITION (bb) == BB_COLD_PARTITION))
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_cold_partition, bb);
>>>>> >>> + if (! VEC_empty (basic_block, bbs_in_cold_partition))
>>>>> >>> + {
>>>>> >>> + bool dom_calculated_here = !dom_info_available_p (CDI_DOMINATORS);
>>>>> >>> + basic_block son;
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + calculate_dominance_info (CDI_DOMINATORS);
>>>>> >>> +
>>>>> >>> + while (! VEC_empty (basic_block, bbs_in_cold_partition))
>>>>> >>> + {
>>>>> >>> + bb = VEC_pop (basic_block, bbs_in_cold_partition);
>>>>> >>> + if ((BB_PARTITION (bb) != BB_COLD_PARTITION))
>>>>> >>> + {
>>>>> >>> + error ("non-cold basic block %d dominated "
>>>>> >>> + "by a block in the cold partition", bb->index);
>>>>> >>> + err = 1;
>>>>> >>> + }
>>>>> >>> + for (son = first_dom_son (CDI_DOMINATORS, bb);
>>>>> >>> + son;
>>>>> >>> + son = next_dom_son (CDI_DOMINATORS, son))
>>>>> >>> + VEC_safe_push (basic_block, heap, bbs_in_cold_partition, son);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> + if (dom_calculated_here)
>>>>> >>> + free_dominance_info (CDI_DOMINATORS);
>>>>> >>> + }
>>>>> >>> +
>>>>> >>> /* Clean up. */
>>>>> >>> return err;
>>>>> >>> }
>>>>> >>> @@ -2965,14 +3158,41 @@ record_effective_endpoints (void)
>>>>> >>> else
>>>>> >>> cfg_layout_function_header = NULL_RTX;
>>>>> >>>
>>>>> >>> + had_sec_boundary_notes = false;
>>>>> >>> +
>>>>> >>> next_insn = get_insns ();
>>>>> >>> FOR_EACH_BB (bb)
>>>>> >>> {
>>>>> >>> rtx end;
>>>>> >>>
>>>>> >>> if (PREV_INSN (BB_HEAD (bb)) && next_insn != BB_HEAD (bb))
>>>>> >>> - BB_HEADER (bb) = unlink_insn_chain (next_insn,
>>>>> >>> - PREV_INSN (BB_HEAD (bb)));
>>>>> >>> + {
>>>>> >>> + /* Rather than try to keep section boundary notes incrementally
>>>>> >>> + up-to-date through cfg layout optimizations, simply remove them
>>>>> >>> + and flag that they should be re-inserted when exiting
>>>>> >>> + cfg layout mode. */
>>>>> >>> + rtx check_insn = next_insn;
>>>>> >>> + while (check_insn)
>>>>> >>> + {
>>>>> >>> + if (NOTE_P (check_insn)
>>>>> >>> + && NOTE_KIND (check_insn) == NOTE_INSN_SWITCH_TEXT_SECTIONS)
>>>>> >>> + {
>>>>> >>> + had_sec_boundary_notes |= true;
>>>>> >>> + /* Remove note from chain. Grab new next_insn first. */
>>>>> >>> + if (next_insn == check_insn)
>>>>> >>> + next_insn = NEXT_INSN (check_insn);
>>>>> >>> + /* Delete note. */
>>>>> >>> + delete_insn (check_insn);
>>>>> >>> + /* There will only be one. */
>>>>> >>> + break;
>>>>> >>> + }
>>>>> >>> + check_insn = NEXT_INSN (check_insn);
>>>>> >>> + }
>>>>> >>> + /* If we still have header instructions left after above loop. */
>>>>> >>> + if (next_insn != BB_HEAD (bb))
>>>>> >>> + BB_HEADER (bb) = unlink_insn_chain (next_insn,
>>>>> >>> + PREV_INSN (BB_HEAD (bb)));
>>>>> >>> + }
>>>>> >>> end = skip_insns_after_block (bb);
>>>>> >>> if (NEXT_INSN (BB_END (bb)) && BB_END (bb) != end)
>>>>> >>> BB_FOOTER (bb) = unlink_insn_chain (NEXT_INSN (BB_END (bb)), end);
>>>>> >>> @@ -3000,7 +3220,7 @@ outof_cfg_layout_mode (void)
>>>>> >>> if (bb->next_bb != EXIT_BLOCK_PTR)
>>>>> >>> bb->aux = bb->next_bb;
>>>>> >>>
>>>>> >>> - cfg_layout_finalize ();
>>>>> >>> + cfg_layout_finalize (false);
>>>>> >>>
>>>>> >>> return 0;
>>>>> >>> }
>>>>> >>> @@ -3120,10 +3340,13 @@ relink_block_chain (bool stay_in_cfglayout_mode)
>>>>> >>> }
>>>>> >>>
>>>>> >>>
>>>>> >>> -/* Given a reorder chain, rearrange the code to match. */
>>>>> >>> +/* Given a reorder chain, rearrange the code to match. If
>>>>> >>> + this is called when we will FINALIZE_REORDER_BLOCKS, or when
>>>>> >>> + section boundary notes were removed on entry to cfg layout
>>>>> >>> + mode, insert section boundary notes here. */
>>>>> >>>
>>>>> >>> static void
>>>>> >>> -fixup_reorder_chain (void)
>>>>> >>> +fixup_reorder_chain (bool finalize_reorder_blocks)
>>>>> >>> {
>>>>> >>> basic_block bb;
>>>>> >>> rtx insn = NULL;
>>>>> >>> @@ -3150,7 +3373,7 @@ static void
>>>>> >>> PREV_INSN (BB_HEADER (bb)) = insn;
>>>>> >>> insn = BB_HEADER (bb);
>>>>> >>> while (NEXT_INSN (insn))
>>>>> >>> - insn = NEXT_INSN (insn);
>>>>> >>> + insn = NEXT_INSN (insn);
>>>>> >>> }
>>>>> >>> if (insn)
>>>>> >>> NEXT_INSN (insn) = BB_HEAD (bb);
>>>>> >>> @@ -3175,6 +3398,11 @@ static void
>>>>> >>> insn = NEXT_INSN (insn);
>>>>> >>>
>>>>> >>> set_last_insn (insn);
>>>>> >>> +
>>>>> >>> + /* Add NOTE_INSN_SWITCH_TEXT_SECTIONS notes. */
>>>>> >>> + if (had_sec_boundary_notes || finalize_reorder_blocks)
>>>>> >>> + insert_section_boundary_note ();
>>>>> >>> +
>>>>> >>> #ifdef ENABLE_CHECKING
>>>>> >>> verify_insn_chain ();
>>>>> >>> #endif
>>>>> >>> @@ -3187,7 +3415,7 @@ static void
>>>>> >>> edge e_fall, e_taken, e;
>>>>> >>> rtx bb_end_insn;
>>>>> >>> rtx ret_label = NULL_RTX;
>>>>> >>> - basic_block nb, src_bb;
>>>>> >>> + basic_block nb;
>>>>> >>> edge_iterator ei;
>>>>> >>>
>>>>> >>> if (EDGE_COUNT (bb->succs) == 0)
>>>>> >>> @@ -3322,7 +3550,6 @@ static void
>>>>> >>> /* We got here if we need to add a new jump insn.
>>>>> >>> Note force_nonfallthru can delete E_FALL and thus we have to
>>>>> >>> save E_FALL->src prior to the call to force_nonfallthru. */
>>>>> >>> - src_bb = e_fall->src;
>>>>> >>> nb = force_nonfallthru_and_redirect (e_fall, e_fall->dest, ret_label);
>>>>> >>> if (nb)
>>>>> >>> {
>>>>> >>> @@ -3330,17 +3557,6 @@ static void
>>>>> >>> bb->aux = nb;
>>>>> >>> /* Don't process this new block. */
>>>>> >>> bb = nb;
>>>>> >>> -
>>>>> >>> - /* Make sure new bb is tagged for correct section (same as
>>>>> >>> - fall-thru source, since you cannot fall-thru across
>>>>> >>> - section boundaries). */
>>>>> >>> - BB_COPY_PARTITION (src_bb, single_pred (bb));
>>>>> >>> - if (flag_reorder_blocks_and_partition
>>>>> >>> - && targetm_common.have_named_sections
>>>>> >>> - && JUMP_P (BB_END (bb))
>>>>> >>> - && !any_condjump_p (BB_END (bb))
>>>>> >>> - && (EDGE_SUCC (bb, 0)->flags & EDGE_CROSSING))
>>>>> >>> - add_reg_note (BB_END (bb), REG_CROSSING_JUMP, NULL_RTX);
>>>>> >>> }
>>>>> >>> }
>>>>> >>>
>>>>> >>> @@ -3644,10 +3860,11 @@ duplicate_insn_chain (rtx from, rtx to)
>>>>> >>> case NOTE_INSN_FUNCTION_BEG:
>>>>> >>> /* There is always just single entry to function. */
>>>>> >>> case NOTE_INSN_BASIC_BLOCK:
>>>>> >>> + /* We should only switch text sections once. */
>>>>> >>> + case NOTE_INSN_SWITCH_TEXT_SECTIONS:
>>>>> >>> break;
>>>>> >>>
>>>>> >>> case NOTE_INSN_EPILOGUE_BEG:
>>>>> >>> - case NOTE_INSN_SWITCH_TEXT_SECTIONS:
>>>>> >>> emit_note_copy (insn);
>>>>> >>> break;
>>>>> >>>
>>>>> >>> @@ -3759,10 +3976,13 @@ break_superblocks (void)
>>>>> >>> }
>>>>> >>>
>>>>> >>> /* Finalize the changes: reorder insn list according to the sequence specified
>>>>> >>> - by aux pointers, enter compensation code, rebuild scope forest. */
>>>>> >>> + by aux pointers, enter compensation code, rebuild scope forest. If
>>>>> >>> + this is called when we will FINALIZE_REORDER_BLOCKS, indicate that
>>>>> >>> + to fixup_reorder_chain so that it can insert the proper switch text
>>>>> >>> + section notes. */
>>>>> >>>
>>>>> >>> void
>>>>> >>> -cfg_layout_finalize (void)
>>>>> >>> +cfg_layout_finalize (bool finalize_reorder_blocks)
>>>>> >>> {
>>>>> >>> #ifdef ENABLE_CHECKING
>>>>> >>> verify_flow_info ();
>>>>> >>> @@ -3775,7 +3995,7 @@ void
>>>>> >>> #endif
>>>>> >>> )
>>>>> >>> fixup_fallthru_exit_predecessor ();
>>>>> >>> - fixup_reorder_chain ();
>>>>> >>> + fixup_reorder_chain (finalize_reorder_blocks);
>>>>> >>>
>>>>> >>> rebuild_jump_labels (get_insns ());
>>>>> >>> delete_dead_jumptables ();
>>>>> >>> @@ -4454,8 +4674,7 @@ rtl_can_remove_branch_p (const_edge e)
>>>>> >>> if (e->flags & (EDGE_ABNORMAL_CALL | EDGE_EH))
>>>>> >>> return false;
>>>>> >>>
>>>>> >>> - if (find_reg_note (insn, REG_CROSSING_JUMP, NULL_RTX)
>>>>> >>> - || BB_PARTITION (src) != BB_PARTITION (target))
>>>>> >>> + if (BB_PARTITION (src) != BB_PARTITION (target))
>>>>> >>> return false;
>>>>> >>>
>>>>> >>> if (!onlyjump_p (insn)
>>>>> >>>
>>>>> >>> --
>>>>> >>> This patch is available for review at http://codereview.appspot.com/6823047
>>>>> >>
>>>>> >>
>>>>> >>
>>>>> >> --
>>>>> >> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>>>
>>>
>>>
>>> --
>>> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413
>
>
>
> --
> Teresa Johnson | Software Engineer | tejohnson@google.com | 408-460-2413