diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 12 | ||||
| -rw-r--r-- | gcc/dse.c | 33 |
2 files changed, 29 insertions, 16 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f3db7fd..53eb2f2 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,15 @@ +2015-01-08 Jakub Jelinek <jakub@redhat.com> + + PR target/55023 + PR middle-end/64388 + * dse.c (struct insn_info): Mention frame_read set also + before reload for tail calls on some targets. + (scan_insn): Revert 2014-12-22 change. Set frame_read + also before reload for tail calls if + HARD_FRAME_POINTER_IS_ARG_POINTER. Call add_wild_read + instead of add_non_frame_wild_read for non-const/memset + tail calls after reload. + 2015-01-08 Jason Merrill <jason@redhat.com> * ubsan.c (do_ubsan_in_current_function): New. @@ -371,9 +371,11 @@ struct insn_info either stack pointer or hard frame pointer based. This means that we have no other choice than also killing all the frame pointer based stores upon encountering a const function call. - This field is set after reload for const function calls. Having - this set is less severe than a wild read, it just means that all - the frame related stores are killed rather than all the stores. */ + This field is set after reload for const function calls and before + reload for const tail function calls on targets where arg pointer + is the frame pointer. Having this set is less severe than a wild + read, it just means that all the frame related stores are killed + rather than all the stores. */ bool frame_read; /* This field is only used for the processing of const functions. @@ -2483,17 +2485,6 @@ scan_insn (bb_info_t bb_info, rtx_insn *insn) insn_info->cannot_delete = true; - /* Arguments for a sibling call that are pushed to memory are passed - using the incoming argument pointer of the current function. These - may or may not be frame related depending on the target. Since - argument pointer related stores are not currently tracked, we treat - a sibling call as though it does a wild read. */ - if (SIBLING_CALL_P (insn)) - { - add_wild_read (bb_info); - return; - } - /* Const functions cannot do anything bad i.e. read memory, however, they can read their parameters which may have been pushed onto the stack. @@ -2527,7 +2518,13 @@ scan_insn (bb_info_t bb_info, rtx_insn *insn) const_call ? "const" : "memset", INSN_UID (insn)); /* See the head comment of the frame_read field. */ - if (reload_completed) + if (reload_completed + /* Tail calls are storing their arguments using + arg pointer. If it is a frame pointer on the target, + even before reload we need to kill frame pointer based + stores. */ + || (SIBLING_CALL_P (insn) + && HARD_FRAME_POINTER_IS_ARG_POINTER)) insn_info->frame_read = true; /* Loop over the active stores and remove those which are @@ -2601,7 +2598,11 @@ scan_insn (bb_info_t bb_info, rtx_insn *insn) } } } - + else if (SIBLING_CALL_P (insn) && reload_completed) + /* Arguments for a sibling call that are pushed to memory are passed + using the incoming argument pointer of the current function. After + reload that might be (and likely is) frame pointer based. */ + add_wild_read (bb_info); else /* Every other call, including pure functions, may read any memory that is not relative to the frame. */ |