diff options
Diffstat (limited to 'contrib/gcc/regmove.c')
| -rw-r--r-- | contrib/gcc/regmove.c | 34 |
1 files changed, 8 insertions, 26 deletions
diff --git a/contrib/gcc/regmove.c b/contrib/gcc/regmove.c index 800859582c75..81a3520a4fef 100644 --- a/contrib/gcc/regmove.c +++ b/contrib/gcc/regmove.c @@ -62,7 +62,7 @@ static int find_matches PROTO((rtx, struct match *)); static int fixup_match_1 PROTO((rtx, rtx, rtx, rtx, rtx, int, int, int, FILE *)) ; static int reg_is_remote_constant_p PROTO((rtx, rtx, rtx)); -static int stable_and_no_regs_but_for_p PROTO((rtx, rtx, rtx)); +static int stable_but_for_p PROTO((rtx, rtx, rtx)); static int regclass_compatible_p PROTO((int, int)); static int loop_depth; @@ -1663,12 +1663,6 @@ fixup_match_1 (insn, set, src, src_subreg, dst, backward, operand_number, rtx src_note = find_reg_note (insn, REG_DEAD, src), dst_note; int length, s_length, true_loop_depth; - /* If SRC is marked as unchanging, we may not change it. - ??? Maybe we could get better code by removing the unchanging bit - instead, and changing it back if we don't succeed? */ - if (RTX_UNCHANGING_P (src)) - return 0; - if (! src_note) { /* Look for (set (regX) (op regA constX)) @@ -1685,7 +1679,7 @@ fixup_match_1 (insn, set, src, src_subreg, dst, backward, operand_number, && XEXP (SET_SRC (set), 0) == src && GET_CODE (XEXP (SET_SRC (set), 1)) == CONST_INT) insn_const = INTVAL (XEXP (SET_SRC (set), 1)); - else if (! stable_and_no_regs_but_for_p (SET_SRC (set), src, dst)) + else if (! stable_but_for_p (SET_SRC (set), src, dst)) return 0; else /* We might find a src_note while scanning. */ @@ -2095,16 +2089,10 @@ fixup_match_1 (insn, set, src, src_subreg, dst, backward, operand_number, } -/* return nonzero if X is stable and mentions no regsiters but for - mentioning SRC or mentioning / changing DST . If in doubt, presume - it is unstable. - The rationale is that we want to check if we can move an insn easily - while just paying attention to SRC and DST. A register is considered - stable if it has the RTX_UNCHANGING_P bit set, but that would still - leave the burden to update REG_DEAD / REG_UNUSED notes, so we don't - want any registers but SRC and DST. */ +/* return nonzero if X is stable but for mentioning SRC or mentioning / + changing DST . If in doubt, presume it is unstable. */ static int -stable_and_no_regs_but_for_p (x, src, dst) +stable_but_for_p (x, src, dst) rtx x, src, dst; { RTX_CODE code = GET_CODE (x); @@ -2115,19 +2103,13 @@ stable_and_no_regs_but_for_p (x, src, dst) int i; char *fmt = GET_RTX_FORMAT (code); for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--) - if (fmt[i] == 'e' - && ! stable_and_no_regs_but_for_p (XEXP (x, i), src, dst)) + if (fmt[i] == 'e' && ! stable_but_for_p (XEXP (x, i), src, dst)) return 0; return 1; } case 'o': - if (code == REG) - return x == src || x == dst; - /* If this is a MEM, look inside - there might be a register hidden in - the address of an unchanging MEM. */ - if (code == MEM - && ! stable_and_no_regs_but_for_p (XEXP (x, 0), src, dst)) - return 0; + if (x == src || x == dst) + return 1; /* fall through */ default: return ! rtx_unstable_p (x); |