diff options
| author | Richard Kenner <kenner@gcc.gnu.org> | 1993-09-17 18:10:33 -0400 |
|---|---|---|
| committer | Richard Kenner <kenner@gcc.gnu.org> | 1993-09-17 18:10:33 -0400 |
| commit | 31c85c78b1a99acc017177f21ac497ec243a8028 (patch) | |
| tree | 9bdc7d502577b727def0ab39f3ffa85025869075 /gcc | |
| parent | c1719013cf972ac1af92e6e23c1d3017d047a43a (diff) | |
| download | gcc-31c85c78b1a99acc017177f21ac497ec243a8028.zip gcc-31c85c78b1a99acc017177f21ac497ec243a8028.tar.gz gcc-31c85c78b1a99acc017177f21ac497ec243a8028.tar.bz2 | |
(fold_rtx, case SUBREG): If paradoxical SUBREG of a constant, return
the constant.
From-SVN: r5346
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/cse.c | 14 |
1 files changed, 10 insertions, 4 deletions
@@ -4582,7 +4582,9 @@ fold_rtx (x, insn) extra bits would have. However, if the operand is equivalent to a SUBREG whose operand is the same as our mode, and all the modes are within a word, we can just use the inner operand - because these SUBREGs just say how to treat the register. */ + because these SUBREGs just say how to treat the register. + + Similarly if we find an integer constant. */ if (GET_MODE_SIZE (mode) > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x)))) { @@ -4593,9 +4595,13 @@ fold_rtx (x, insn) && GET_MODE_SIZE (imode) <= UNITS_PER_WORD && (elt = lookup (SUBREG_REG (x), HASH (SUBREG_REG (x), imode), imode)) != 0) - { - for (elt = elt->first_same_value; - elt; elt = elt->next_same_value) + for (elt = elt->first_same_value; + elt; elt = elt->next_same_value) + { + if (CONSTANT_P (elt->exp) + && GET_MODE (elt->exp) == VOIDmode) + return elt->exp; + if (GET_CODE (elt->exp) == SUBREG && GET_MODE (SUBREG_REG (elt->exp)) == mode && exp_equiv_p (elt->exp, elt->exp, 1, 0)) |