diff options
Diffstat (limited to 'gcc/final.c')
| -rw-r--r-- | gcc/final.c | 19 |
1 files changed, 18 insertions, 1 deletions
diff --git a/gcc/final.c b/gcc/final.c index bf4f521..3952b9f 100644 --- a/gcc/final.c +++ b/gcc/final.c @@ -2608,7 +2608,24 @@ alter_subreg (rtx *xp) /* simplify_subreg does not remove subreg from volatile references. We are required to. */ if (MEM_P (y)) - *xp = adjust_address (y, GET_MODE (x), SUBREG_BYTE (x)); + { + int offset = SUBREG_BYTE (x); + + /* For paradoxical subregs on big-endian machines, SUBREG_BYTE + contains 0 instead of the proper offset. See simplify_subreg. */ + if (offset == 0 + && GET_MODE_SIZE (GET_MODE (y)) < GET_MODE_SIZE (GET_MODE (x))) + { + int difference = GET_MODE_SIZE (GET_MODE (y)) + - GET_MODE_SIZE (GET_MODE (x)); + if (WORDS_BIG_ENDIAN) + offset += (difference / UNITS_PER_WORD) * UNITS_PER_WORD; + if (BYTES_BIG_ENDIAN) + offset += difference % UNITS_PER_WORD; + } + + *xp = adjust_address (y, GET_MODE (x), offset); + } else { rtx new = simplify_subreg (GET_MODE (x), y, GET_MODE (y), |