diff options
Diffstat (limited to 'gcc/combine.c')
| -rw-r--r-- | gcc/combine.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/gcc/combine.c b/gcc/combine.c index de46091..89383a4 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -776,11 +776,15 @@ can_combine_p (insn, i3, pred, succ, pdest, psrc) else if (GET_CODE (dest) != CC0) return 0; - /* Don't substitute for a register intended as a clobberable operand. */ + /* Don't substitute for a register intended as a clobberable operand. + Similarly, don't substitute an expression containing a register that + will be clobbered in I3. */ if (GET_CODE (PATTERN (i3)) == PARALLEL) for (i = XVECLEN (PATTERN (i3), 0) - 1; i >= 0; i--) if (GET_CODE (XVECEXP (PATTERN (i3), 0, i)) == CLOBBER - && rtx_equal_p (XEXP (XVECEXP (PATTERN (i3), 0, i), 0), dest)) + && (reg_overlap_mentioned_p (XEXP (XVECEXP (PATTERN (i3), 0, i), 0), + src) + || rtx_equal_p (XEXP (XVECEXP (PATTERN (i3), 0, i), 0), dest))) return 0; /* If INSN contains anything volatile, or is an `asm' (whether volatile |