(use_crosses_set_p): Check for partially overlapping hard regs.

From-SVN: r5163

diff --git a/gcc/combine.c b/gcc/combine.c
index 8abf590d51483510ec8945d70b3b6ede9296e0ae..a270b6bd5738f3cb4f7fef3328ef6983ae599f98 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -9404,14 +9404,20 @@ use_crosses_set_p (x, from_cuid)
   if (code == REG)
     {
       register int regno = REGNO (x);
+      int endreg = regno + (regno < FIRST_PSEUDO_REGISTER
+                           ? HARD_REGNO_NREGS (regno, GET_MODE (x)) : 1);
+      
 #ifdef PUSH_ROUNDING
       /* Don't allow uses of the stack pointer to be moved,
         because we don't know whether the move crosses a push insn.  */
       if (regno == STACK_POINTER_REGNUM)
        return 1;
 #endif
-      return (reg_last_set[regno]
-             && INSN_CUID (reg_last_set[regno]) > from_cuid);
+      for (;regno < endreg; regno++)
+       if (reg_last_set[regno]
+           && INSN_CUID (reg_last_set[regno]) > from_cuid)
+         return 1;
+      return 0;
     }
 
   if (code == MEM && mem_last_set > from_cuid)