diff options
Diffstat (limited to 'gcc/cse.c')
| -rw-r--r-- | gcc/cse.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/gcc/cse.c b/gcc/cse.c index 14ffd801bbe..afdc8daa8b0 100644 --- a/gcc/cse.c +++ b/gcc/cse.c @@ -6196,14 +6196,29 @@ cse_insn (insn, libcall_insn) rtx new_src = 0; unsigned src_hash; struct table_elt *src_elt; + int byte = 0; /* Ignore invalid entries. */ if (GET_CODE (elt->exp) != REG && ! exp_equiv_p (elt->exp, elt->exp, 1, 0)) continue; - new_src - = simplify_gen_subreg (new_mode, elt->exp, elt->mode, 0); + /* Calculate big endian correction for the SUBREG_BYTE + (or equivalent). We have already checked that M1 + ( GET_MODE (dest) ) is not narrower than M2 (new_mode). */ + if (BYTES_BIG_ENDIAN) + byte = (GET_MODE_SIZE (GET_MODE (dest)) + - GET_MODE_SIZE (new_mode)); + new_src = simplify_gen_subreg (new_mode, elt->exp, + GET_MODE (dest), byte); + /* The call to simplify_gen_subreg fails if the value + is VOIDmode, yet we can't do any simplification, e.g. + for EXPR_LISTs denoting function call results. + It is invalid to construct a SUBREG with a VOIDmode + SUBREG_REG, hence a zero new_src means we can't do + this substitution. */ + if (! new_src) + continue; src_hash = HASH (new_src, new_mode); src_elt = lookup (new_src, src_hash, new_mode); |