diff options
Diffstat (limited to 'gcc/rtl.c')
| -rw-r--r-- | gcc/rtl.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/gcc/rtl.c b/gcc/rtl.c index bc49fc86fe9..b2d88f783b7 100644 --- a/gcc/rtl.c +++ b/gcc/rtl.c @@ -256,7 +256,11 @@ copy_rtx (rtx orig) /* SCRATCH must be shared because they represent distinct values. */ return orig; case CLOBBER: - if (REG_P (XEXP (orig, 0)) && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER) + /* Share clobbers of hard registers (like cc0), but do not share pseudo reg + clobbers or clobbers of hard registers that originated as pseudos. + This is needed to allow safe register renaming. */ + if (REG_P (XEXP (orig, 0)) && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER + && ORIGINAL_REGNO (XEXP (orig, 0)) == REGNO (XEXP (orig, 0))) return orig; break; |