diff options
| -rw-r--r-- | gcc/ChangeLog | 3 | ||||
| -rw-r--r-- | gcc/combine.c | 11 |
2 files changed, 13 insertions, 1 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index cd7336e..5e578ae 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,8 @@ 2001-05-21 Richard Henderson <rth@redhat.com> + * combine.c (subst): Do not substitute for a register as + a destination subreg/strict_low_part/zero_extract. + * combine.c (simplify_comparison): Update op1 after constant extension. * recog.c (const_int_operand): Accept only constants valid diff --git a/gcc/combine.c b/gcc/combine.c index e3ad70a..675b1fe 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -3394,7 +3394,16 @@ subst (x, from, to, in_dest, unique_copy) } else if (fmt[i] == 'e') { - if (COMBINE_RTX_EQUAL_P (XEXP (x, i), from)) + /* If this is a register being set, ignore it. */ + new = XEXP (x, i); + if (in_dest + && (code == SUBREG || code == STRICT_LOW_PART + || code == ZERO_EXTRACT) + && i == 0 + && GET_CODE (new) == REG) + ; + + else if (COMBINE_RTX_EQUAL_P (XEXP (x, i), from)) { /* In general, don't install a subreg involving two modes not tieable. It can worsen register |