diff options
Diffstat (limited to 'gcc/alias.c')
| -rw-r--r-- | gcc/alias.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/gcc/alias.c b/gcc/alias.c index 684205cd89e..56660ec38d9 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -1975,6 +1975,34 @@ adjust_offset_for_component_ref (tree x, rtx offset) return GEN_INT (ioffset); } +/* The function returns nonzero if X is an address containg VALUE. */ +static int +value_addr_p (rtx x) +{ + if (GET_CODE (x) == VALUE) + return 1; + if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 0)) == VALUE) + return 1; + return 0; +} + +/* The function returns nonzero if X is a stack address. */ +static int +stack_addr_p (rtx x) +{ + if (x == hard_frame_pointer_rtx || x == frame_pointer_rtx + || x == arg_pointer_rtx || x == stack_pointer_rtx) + return 1; + if (GET_CODE (x) == PLUS + && (XEXP (x, 0) == hard_frame_pointer_rtx + || XEXP (x, 0) == frame_pointer_rtx + || XEXP (x, 0) == arg_pointer_rtx + || XEXP (x, 0) == stack_pointer_rtx) + && CONSTANT_P (XEXP (x, 1))) + return 1; + return 0; +} + /* Return nonzero if we can determine the exprs corresponding to memrefs X and Y and they do not overlap. */ @@ -1984,9 +2012,27 @@ nonoverlapping_memrefs_p (const_rtx x, const_rtx y) tree exprx = MEM_EXPR (x), expry = MEM_EXPR (y); rtx rtlx, rtly; rtx basex, basey; + rtx x_addr, y_addr; rtx moffsetx, moffsety; HOST_WIDE_INT offsetx = 0, offsety = 0, sizex, sizey, tem; + if (flag_ira && optimize && reload_completed) + { + /* We need this code for IRA because of stack slot sharing. RTL + in decl can be different than RTL used in insns. It is a + safe code although it can be conservative sometime. */ + x_addr = canon_rtx (get_addr (XEXP (x, 0))); + y_addr = canon_rtx (get_addr (XEXP (y, 0))); + + if (value_addr_p (x_addr) || value_addr_p (y_addr)) + return 0; + + if (stack_addr_p (x_addr) && stack_addr_p (y_addr) + && memrefs_conflict_p (SIZE_FOR_MODE (y), y_addr, + SIZE_FOR_MODE (x), x_addr, 0)) + return 0; + } + /* Unless both have exprs, we can't tell anything. */ if (exprx == 0 || expry == 0) return 0; |