diff options
Diffstat (limited to 'gnu/usr.bin/cc/cc_int/reorg.c')
| -rw-r--r-- | gnu/usr.bin/cc/cc_int/reorg.c | 56 |
1 files changed, 50 insertions, 6 deletions
diff --git a/gnu/usr.bin/cc/cc_int/reorg.c b/gnu/usr.bin/cc/cc_int/reorg.c index 250cf99..c90c055 100644 --- a/gnu/usr.bin/cc/cc_int/reorg.c +++ b/gnu/usr.bin/cc/cc_int/reorg.c @@ -244,12 +244,13 @@ static rtx steal_delay_list_from_fallthrough PROTO((rtx, rtx, rtx, rtx, struct resources *, int, int *, int *)); static void try_merge_delay_insns PROTO((rtx, rtx)); -static int redundant_insn_p PROTO((rtx, rtx, rtx)); +static rtx redundant_insn_p PROTO((rtx, rtx, rtx)); static int own_thread_p PROTO((rtx, rtx, int)); static int find_basic_block PROTO((rtx)); static void update_block PROTO((rtx, rtx)); static int reorg_redirect_jump PROTO((rtx, rtx)); static void update_reg_dead_notes PROTO((rtx, rtx)); +static void update_reg_unused_notes PROTO((rtx, rtx)); static void update_live_status PROTO((rtx, rtx)); static rtx next_insn_no_annul PROTO((rtx)); static void mark_target_live_regs PROTO((rtx, struct resources *)); @@ -1922,7 +1923,7 @@ try_merge_delay_insns (insn, thread) redundant insn, but the cost of splitting seems greater than the possible gain in rare cases. */ -static int +static rtx redundant_insn_p (insn, target, delay_list) rtx insn; rtx target; @@ -2079,7 +2080,7 @@ redundant_insn_p (insn, target, delay_list) { /* Show that this insn will be used in the sequel. */ INSN_FROM_TARGET_P (candidate) = 0; - return 1; + return candidate; } /* Unless this is an annulled insn from the target of a branch, @@ -2101,7 +2102,7 @@ redundant_insn_p (insn, target, delay_list) /* See if TRIAL is the same as INSN. */ pat = PATTERN (trial); if (rtx_equal_p (pat, ipat)) - return 1; + return trial; /* Can't go any further if TRIAL conflicts with INSN. */ if (insn_sets_resource_p (trial, &needed, 1)) @@ -2276,6 +2277,33 @@ update_reg_dead_notes (insn, delayed_insn) } } } + +/* Delete any REG_UNUSED notes that exist on INSN but not on REDUNDANT_INSN. + + This handles the case of udivmodXi4 instructions which optimize their + output depending on whether any REG_UNUSED notes are present. + we must make sure that INSN calculates as many results as REDUNDANT_INSN + does. */ + +static void +update_reg_unused_notes (insn, redundant_insn) + rtx insn, redundant_insn; +{ + rtx p, link, next; + + for (link = REG_NOTES (insn); link; link = next) + { + next = XEXP (link, 1); + + if (REG_NOTE_KIND (link) != REG_UNUSED + || GET_CODE (XEXP (link, 0)) != REG) + continue; + + if (! find_regno_note (redundant_insn, REG_UNUSED, + REGNO (XEXP (link, 0)))) + remove_note (insn, link); + } +} /* Marks registers possibly live at the current place being scanned by mark_target_live_regs. Used only by next two function. */ @@ -3279,10 +3307,12 @@ fill_slots_from_thread (insn, condition, thread, opposite_thread, likely, #endif ) { + rtx prior_insn; + /* If TRIAL is redundant with some insn before INSN, we don't actually need to add it to the delay list; we can merely pretend we did. */ - if (redundant_insn_p (trial, insn, delay_list)) + if (prior_insn = redundant_insn_p (trial, insn, delay_list)) { if (own_thread) { @@ -3297,7 +3327,10 @@ fill_slots_from_thread (insn, condition, thread, opposite_thread, likely, delete_insn (trial); } else - new_thread = next_active_insn (trial); + { + update_reg_unused_notes (prior_insn, trial); + new_thread = next_active_insn (trial); + } continue; } @@ -3940,6 +3973,17 @@ relax_delay_slots (first) if (invert_jump (delay_insn, label)) { + int i; + + /* Must update the INSN_FROM_TARGET_P bits now that + the branch is reversed, so that mark_target_live_regs + will handle the delay slot insn correctly. */ + for (i = 1; i < XVECLEN (PATTERN (insn), 0); i++) + { + rtx slot = XVECEXP (PATTERN (insn), 0, i); + INSN_FROM_TARGET_P (slot) = ! INSN_FROM_TARGET_P (slot); + } + delete_insn (next); next = insn; } |
