diff options
Diffstat (limited to 'gcc/lower-subreg.c')
| -rw-r--r-- | gcc/lower-subreg.c | 94 |
1 files changed, 8 insertions, 86 deletions
diff --git a/gcc/lower-subreg.c b/gcc/lower-subreg.c index a9e7da998a4..67a95984fab 100644 --- a/gcc/lower-subreg.c +++ b/gcc/lower-subreg.c @@ -225,11 +225,9 @@ enum classify_move_insn { /* Not a simple move from one location to another. */ NOT_SIMPLE_MOVE, - /* A simple move from one pseudo-register to another with no - REG_RETVAL note. */ + /* A simple move from one pseudo-register to another. */ SIMPLE_PSEUDO_REG_MOVE, - /* A simple move involving a non-pseudo-register, or from one - pseudo-register to another with a REG_RETVAL note. */ + /* A simple move involving a non-pseudo-register. */ SIMPLE_MOVE }; @@ -304,10 +302,10 @@ find_decomposable_subregs (rtx *px, void *data) If this is not a simple copy from one location to another, then we can not decompose this register. If this is a simple - copy from one pseudo-register to another, with no REG_RETVAL - note, and the mode is right, then we mark the register as - decomposable. Otherwise we don't say anything about this - register--it could be decomposed, but whether that would be + copy from one pseudo-register to another, and the mode is right + then we mark the register as decomposable. + Otherwise we don't say anything about this register -- + it could be decomposed, but whether that would be profitable depends upon how it is used elsewhere. We only set bits in the bitmap for multi-word @@ -558,47 +556,6 @@ move_eh_region_note (rtx insn, rtx insns) } } -/* If there is a REG_LIBCALL note on OLD_START, move it to NEW_START, - and link the corresponding REG_RETVAL note to NEW_START. */ - -static void -move_libcall_note (rtx old_start, rtx new_start) -{ - rtx note0, note1, end; - - note0 = find_reg_note (old_start, REG_LIBCALL, NULL); - if (note0 == NULL_RTX) - return; - - remove_note (old_start, note0); - end = XEXP (note0, 0); - note1 = find_reg_note (end, REG_RETVAL, NULL); - - XEXP (note0, 1) = REG_NOTES (new_start); - REG_NOTES (new_start) = note0; - XEXP (note1, 0) = new_start; -} - -/* Remove any REG_RETVAL note, the corresponding REG_LIBCALL note, and - any markers for a no-conflict block. We have decomposed the - registers so the non-conflict is now obvious. */ - -static void -remove_retval_note (rtx insn1) -{ - rtx note0, insn0, note1; - - note1 = find_reg_note (insn1, REG_RETVAL, NULL); - if (note1 == NULL_RTX) - return; - - insn0 = XEXP (note1, 0); - note0 = find_reg_note (insn0, REG_LIBCALL, NULL); - - remove_note (insn0, note0); - remove_note (insn1, note1); -} - /* Resolve any decomposed registers which appear in register notes on INSN. */ @@ -612,10 +569,7 @@ resolve_reg_notes (rtx insn) { int old_count = num_validated_changes (); if (for_each_rtx (&XEXP (note, 0), resolve_subreg_use, NULL)) - { - remove_note (insn, note); - remove_retval_note (insn); - } + remove_note (insn, note); else if (old_count != num_validated_changes ()) df_notes_rescan (insn); @@ -870,8 +824,6 @@ resolve_simple_move (rtx set, rtx insn) emit_insn_before (insns, insn); - move_libcall_note (insn, insns); - remove_retval_note (insn); delete_insn (insn); return insns; @@ -1156,34 +1108,8 @@ decompose_multiword_subregs (void) cmi = NOT_SIMPLE_MOVE; else { - bool retval; - - retval = find_reg_note (insn, REG_RETVAL, NULL_RTX) != NULL_RTX; - - if (find_pseudo_copy (set) && !retval) + if (find_pseudo_copy (set)) cmi = SIMPLE_PSEUDO_REG_MOVE; - else if (retval - && REG_P (SET_SRC (set)) - && HARD_REGISTER_P (SET_SRC (set))) - { - rtx note; - - /* We don't want to decompose an assignment which - copies the value returned by a libcall to a - pseudo-register. Doing that will lose the RETVAL - note with no real gain. */ - cmi = NOT_SIMPLE_MOVE; - - /* If we have a RETVAL note, there should be an - EQUAL note. We don't want to decompose any - registers which that EQUAL note refers to - directly. If we do, we will no longer know the - value of the libcall. */ - note = find_reg_equal_equiv_note (insn); - if (note != NULL_RTX) - for_each_rtx (&XEXP (note, 0), find_decomposable_subregs, - &cmi); - } else cmi = SIMPLE_MOVE; } @@ -1277,8 +1203,6 @@ decompose_multiword_subregs (void) insn = resolve_simple_move (set, insn); if (insn != orig_insn) { - remove_retval_note (insn); - recog_memoized (insn); extract_insn (insn); @@ -1319,8 +1243,6 @@ decompose_multiword_subregs (void) i = apply_change_group (); gcc_assert (i); - - remove_retval_note (insn); } } } |