diff options
Diffstat (limited to 'gcc/expmed.c')
| -rw-r--r-- | gcc/expmed.c | 18 |
1 files changed, 16 insertions, 2 deletions
diff --git a/gcc/expmed.c b/gcc/expmed.c index 0daf7fa..6099c4b 100644 --- a/gcc/expmed.c +++ b/gcc/expmed.c @@ -1991,8 +1991,22 @@ extract_low_bits (enum machine_mode mode, enum machine_mode src_mode, rtx src) return src; if (CONSTANT_P (src)) - return simplify_gen_subreg (mode, src, src_mode, - subreg_lowpart_offset (mode, src_mode)); + { + /* simplify_gen_subreg can't be used here, as if simplify_subreg + fails, it will happily create (subreg (symbol_ref)) or similar + invalid SUBREGs. */ + unsigned int byte = subreg_lowpart_offset (mode, src_mode); + rtx ret = simplify_subreg (mode, src, src_mode, byte); + if (ret) + return ret; + + if (GET_MODE (src) == VOIDmode + || !validate_subreg (mode, src_mode, src, byte)) + return NULL_RTX; + + src = force_reg (GET_MODE (src), src); + return gen_rtx_SUBREG (mode, src, byte); + } if (GET_MODE_CLASS (mode) == MODE_CC || GET_MODE_CLASS (src_mode) == MODE_CC) return NULL_RTX; |