diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index 23136194bf0..1d6a5b270b7 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -2316,6 +2316,10 @@ try_combine (i3, i2, i1, new_direct_jump_p) copy. This saves at least one insn, more if register allocation can eliminate the copy. + We cannot do this if the destination of the first assignment is a + condition code register or cc0. We eliminate this case by making sure + the SET_DEST and SET_SRC have the same mode. + We cannot do this if the destination of the second assignment is a register that we have already assumed is zero-extended. Similarly for a SUBREG of such a register. */ @@ -2325,6 +2329,8 @@ try_combine (i3, i2, i1, new_direct_jump_p) && XVECLEN (newpat, 0) == 2 && GET_CODE (XVECEXP (newpat, 0, 0)) == SET && GET_CODE (SET_SRC (XVECEXP (newpat, 0, 0))) == SIGN_EXTEND + && (GET_MODE (SET_DEST (XVECEXP (newpat, 0, 0))) + == GET_MODE (SET_SRC (XVECEXP (newpat, 0, 0)))) && GET_CODE (XVECEXP (newpat, 0, 1)) == SET && rtx_equal_p (SET_SRC (XVECEXP (newpat, 0, 1)), XEXP (SET_SRC (XVECEXP (newpat, 0, 0)), 0)) |

