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| author | Richard Kenner <kenner@gcc.gnu.org> | 1994-04-21 18:27:25 -0400 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1994-04-21 18:27:25 -0400 |
| commit | c448a43e24ae85ee584aac5113081e4e360c1d81 (patch) | |
| tree | b9927bf68f93b7799a862ecba3ec63de13209b32 /gcc | |
| parent | defb5dab7df1a5162db4718d785ef01d004306e9 (diff) | |
| download | gcc-c448a43e24ae85ee584aac5113081e4e360c1d81.zip gcc-c448a43e24ae85ee584aac5113081e4e360c1d81.tar.gz gcc-c448a43e24ae85ee584aac5113081e4e360c1d81.tar.bz2 | |
(can_combine_p...
(can_combine_p, combinable_i3pat, try_combine): Allow combination
involving hard regs if the hard reg is a user variable.
From-SVN: r7131
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/combine.c | 30 |
1 files changed, 16 insertions, 14 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 0c349a1..41c83dc 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -927,14 +927,16 @@ can_combine_p (insn, i3, pred, succ, pdest, psrc) if (GET_CODE (src) == REG && ((REGNO (dest) < FIRST_PSEUDO_REGISTER && ! HARD_REGNO_MODE_OK (REGNO (dest), GET_MODE (dest))) -#ifdef SMALL_REGISTER_CLASSES - /* Don't extend the life of a hard register. */ - || REGNO (src) < FIRST_PSEUDO_REGISTER -#else + /* Don't extend the life of a hard register unless it is + user variable (if we have few registers) or it can't + fit into the desired register (meaning something special + is going on). */ || (REGNO (src) < FIRST_PSEUDO_REGISTER - && ! HARD_REGNO_MODE_OK (REGNO (src), GET_MODE (src))) + && (! HARD_REGNO_MODE_OK (REGNO (src), GET_MODE (src)) +#ifdef SMALL_REGISTER_CLASSES + || ! REG_USERVAR_P (src) #endif - )) + )))) return 0; } else if (GET_CODE (dest) != CC0) @@ -1038,7 +1040,8 @@ can_combine_p (insn, i3, pred, succ, pdest, psrc) of a SET must prevent combination from occurring. On machines where SMALL_REGISTER_CLASSES is defined, we don't combine - if the destination of a SET is a hard register. + if the destination of a SET is a hard register that isn't a user + variable. Before doing the above check, we first try to expand a field assignment into a set of logical operations. @@ -1108,14 +1111,12 @@ combinable_i3pat (i3, loc, i2dest, i1dest, i1_not_in_src, pi3dest_killed) CALL operation. */ || (GET_CODE (inner_dest) == REG && REGNO (inner_dest) < FIRST_PSEUDO_REGISTER + && (! HARD_REGNO_MODE_OK (REGNO (inner_dest), + GET_MODE (inner_dest)) #ifdef SMALL_REGISTER_CLASSES - && GET_CODE (src) != CALL -#else - && ! HARD_REGNO_MODE_OK (REGNO (inner_dest), - GET_MODE (inner_dest)) + || (GET_CODE (src) != CALL && ! REG_USERVAR_P (inner_dest)) #endif - ) - + )) || (i1_not_in_src && reg_overlap_mentioned_p (i1dest, src))) return 0; @@ -1254,7 +1255,8 @@ try_combine (i3, i2, i1) && REGNO (SET_SRC (PATTERN (i3))) >= FIRST_PSEUDO_REGISTER #ifdef SMALL_REGISTER_CLASSES && (GET_CODE (SET_DEST (PATTERN (i3))) != REG - || REGNO (SET_DEST (PATTERN (i3))) >= FIRST_PSEUDO_REGISTER) + || REGNO (SET_DEST (PATTERN (i3))) >= FIRST_PSEUDO_REGISTER + || REG_USERVAR_P (SET_DEST (PATTERN (i3)))) #endif && find_reg_note (i3, REG_DEAD, SET_SRC (PATTERN (i3))) && GET_CODE (PATTERN (i2)) == PARALLEL |