diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/fwprop.c | 59 |
2 files changed, 45 insertions, 21 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 97b9f9c..58171fa 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2009-08-30 Alan Modra <amodra@bigpond.net.au> + + PR target/41081 + * fwprop.c (get_reg_use_in): Delete. + (free_load_extend): New function. + (forward_propagate_subreg): Use it. + 2009-08-29 Kaz Kojima <kkojima@gcc.gnu.org> * config.gcc (sh*-*-elf): Add superh stuff only for sh*-superh-elf. diff --git a/gcc/fwprop.c b/gcc/fwprop.c index 50daed2..df8c45d 100644 --- a/gcc/fwprop.c +++ b/gcc/fwprop.c @@ -1014,24 +1014,54 @@ try_fwprop_subst (df_ref use, rtx *loc, rtx new_rtx, rtx def_insn, bool set_reg_ return ok; } -#ifdef LOAD_EXTEND_OP -static df_ref -get_reg_use_in (rtx insn, rtx reg) +/* For the given single_set INSN, containing SRC known to be a + ZERO_EXTEND or SIGN_EXTEND of a register, return true if INSN + is redundant due to the register being set by a LOAD_EXTEND_OP + load from memory. */ + +static bool +free_load_extend (rtx src, rtx insn) { + rtx reg; df_ref *use_vec; + df_ref use, def; + + reg = XEXP (src, 0); +#ifdef LOAD_EXTEND_OP + if (LOAD_EXTEND_OP (GET_MODE (reg)) != GET_CODE (src)) +#endif + return false; for (use_vec = DF_INSN_USES (insn); *use_vec; use_vec++) { - df_ref use = *use_vec; + use = *use_vec; if (!DF_REF_IS_ARTIFICIAL (use) && DF_REF_TYPE (use) == DF_REF_REG_USE && DF_REF_REG (use) == reg) - return use; + break; } - return NULL; + if (!use) + return false; + + def = get_def_for_use (use); + if (!def) + return false; + + if (DF_REF_IS_ARTIFICIAL (def)) + return false; + + if (NONJUMP_INSN_P (DF_REF_INSN (def))) + { + rtx patt = PATTERN (DF_REF_INSN (def)); + + if (GET_CODE (patt) == SET + && GET_CODE (SET_SRC (patt)) == MEM + && rtx_equal_p (SET_DEST (patt), reg)) + return true; + } + return false; } -#endif /* If USE is a subreg, see if it can be replaced by a pseudo. */ @@ -1073,26 +1103,13 @@ forward_propagate_subreg (df_ref use, rtx def_insn, rtx def_set) be removed due to it matching a LOAD_EXTEND_OP load from memory. */ else if (subreg_lowpart_p (use_reg)) { -#ifdef LOAD_EXTEND_OP - df_ref prev_use, prev_def; -#endif use_insn = DF_REF_INSN (use); src = SET_SRC (def_set); if ((GET_CODE (src) == ZERO_EXTEND || GET_CODE (src) == SIGN_EXTEND) && REG_P (XEXP (src, 0)) && GET_MODE (XEXP (src, 0)) == use_mode -#ifdef LOAD_EXTEND_OP - && !(LOAD_EXTEND_OP (use_mode) == GET_CODE (src) - && (prev_use = get_reg_use_in (def_insn, XEXP (src, 0))) != NULL - && (prev_def = get_def_for_use (prev_use)) != NULL - && !DF_REF_IS_ARTIFICIAL (prev_def) - && NONJUMP_INSN_P (DF_REF_INSN (prev_def)) - && GET_CODE (PATTERN (DF_REF_INSN (prev_def))) == SET - && GET_CODE (SET_SRC (PATTERN (DF_REF_INSN (prev_def)))) == MEM - && rtx_equal_p (SET_DEST (PATTERN (DF_REF_INSN (prev_def))), - XEXP (src, 0))) -#endif + && !free_load_extend (src, def_insn) && all_uses_available_at (def_insn, use_insn)) return try_fwprop_subst (use, DF_REF_LOC (use), XEXP (src, 0), def_insn, false); |