(find_cross_jump): Two CALL_INSNs only compare equal if

their CALL_INSN_FUNCTION_USAGEs are the same as well.

From-SVN: r7300

diff --git a/gcc/jump.c b/gcc/jump.c
index 7277bd8..c2a1837 100644 (file)
--- a/gcc/jump.c
+++ b/gcc/jump.c
@@ -2275,44 +2275,22 @@ find_cross_jump (e1, e2, minimum, f1, f2)
       p1 = PATTERN (i1);
       p2 = PATTERN (i2);
        
-#ifdef STACK_REGS
-      if (GET_CODE (i1) == CALL_INSN)
-       {
-         /* Compare register usage information for the stack registers.
-            Two CALL_INSNs are only equal if they receive the same
-            (amount of) stack registers as parameters.  If we don't
-            check this the two CALL_INSNs might be merged leaving
-            reg-stack.c with mismatching numbers of stack registers
-            in the same basic block.  */
-
-         register rtx link, op;
-         HARD_REG_SET i1_regset, i2_regset;
-
-         CLEAR_HARD_REG_SET (i1_regset);
-         CLEAR_HARD_REG_SET (i2_regset);
-
-         for (link = CALL_INSN_FUNCTION_USAGE (i1);
-              link;
-              link = XEXP (link, 1))
-           if (GET_CODE (op = XEXP (link, 0)) == USE
-               && STACK_REG_P (SET_DEST (op)))
-             SET_HARD_REG_BIT (i1_regset, REGNO (SET_DEST (op)));
+      /* If this is a CALL_INSN, compare register usage information.
+        If we don't check this on stack register machines, the two
+        CALL_INSNs might be merged leaving reg-stack.c with mismatching
+        numbers of stack registers in the same basic block.
+        If we don't check this on machines with delay slots, a delay slot may
+        be filled that clobbers a parameter expected by the subroutine.
 
-         for (link = CALL_INSN_FUNCTION_USAGE (i2);
-              link;
-              link = XEXP (link, 1))
-           if (GET_CODE (op = XEXP (link, 0)) == USE
-               && STACK_REG_P (SET_DEST (op)))
-             SET_HARD_REG_BIT (i2_regset, REGNO (SET_DEST (op)));
+        ??? We take the simple route for now and assume that if they're
+        equal, they were constructed identically.  */
 
-         GO_IF_HARD_REG_EQUAL (i1_regset, i2_regset, usedmatch);
-
-         lose = 1;
-
-       usedmatch:
-         ;
-       }
+      if (GET_CODE (i1) == CALL_INSN
+         && ! rtx_equal_p (CALL_INSN_FUNCTION_USAGE (i1),
+                           CALL_INSN_FUNCTION_USAGE (i2)))
+       lose = 1;
 
+#ifdef STACK_REGS
       /* If cross_jump_death_matters is not 0, the insn's mode
         indicates whether or not the insn contains any stack-like
         regs. */