alpha.h (REG_OK_FP_BASE_P): New macro.

        * alpha.h (REG_OK_FP_BASE_P): New macro.
        (GO_IF_LEGITIMATE_SIMPLE_ADDRESS): Use it.
        * alpha.md (adddi3+1): New insn to handle large constants off
        the soft frame pointer.
        (adddi3+2): Don't split soft frame pointer or arg pointer additions.

From-SVN: r26530

3 files changed, 47 insertions, 7 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9411c20..6c2b370 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+Sat Apr 17 22:54:17 1999  Richard Henderson  <rth@cygnus.com>
+
+	* alpha.h (REG_OK_FP_BASE_P): New macro.
+	(GO_IF_LEGITIMATE_SIMPLE_ADDRESS): Use it.
+	* alpha.md (adddi3+1): New insn to handle large constants off 
+	the soft frame pointer.
+	(adddi3+2): Don't split soft frame pointer or arg pointer additions.
+
 Sun Apr 18 17:24:10 1999  Michael Hayes  <m.hayes@elec.canterbury.ac.nz>
 
 	* config/c4x/c4x.c (legitimize_operands): Use rtx_cost
diff --git a/gcc/config/alpha/alpha.h b/gcc/config/alpha/alpha.h
index fe31dc3..2026ca9 100644
--- a/gcc/config/alpha/alpha.h
+++ b/gcc/config/alpha/alpha.h
@@ -1386,18 +1386,32 @@ extern void alpha_init_expanders ();
 /* Nonzero if X is a hard reg that can be used as an index
    or if it is a pseudo reg.  */
 #define REG_OK_FOR_INDEX_P(X) 0
+
 /* Nonzero if X is a hard reg that can be used as a base reg
    or if it is a pseudo reg.  */
 #define REG_OK_FOR_BASE_P(X)  \
   (REGNO (X) < 32 || REGNO (X) == 63 || REGNO (X) >= FIRST_PSEUDO_REGISTER)
 
+/* ??? Nonzero if X is the frame pointer, or some virtual register
+   that may eliminate to the frame pointer.  These will be allowed to
+   have offsets greater than 32K.  This is done because register
+   elimination offsets will change the hi/lo split, and if we split
+   before reload, we will require additional instructions.   */
+#define REG_OK_FP_BASE_P(X)			\
+  (REGNO (X) == 31 || REGNO (X) == 63		\
+   || (REGNO (X) >= FIRST_PSEUDO_REGISTER	\
+       && REGNO (X) < LAST_VIRTUAL_REGISTER))
+
 #else
 
 /* Nonzero if X is a hard reg that can be used as an index.  */
 #define REG_OK_FOR_INDEX_P(X) REGNO_OK_FOR_INDEX_P (REGNO (X))
+
 /* Nonzero if X is a hard reg that can be used as a base reg.  */
 #define REG_OK_FOR_BASE_P(X) REGNO_OK_FOR_BASE_P (REGNO (X))
 
+#define REG_OK_FP_BASE_P(X) 0
+
 #endif
 
 /* GO_IF_LEGITIMATE_ADDRESS recognizes an RTL expression
@@ -1418,10 +1432,14 @@ extern void alpha_init_expanders ();
   if (CONSTANT_ADDRESS_P (X))			\
     goto ADDR;					\
   if (GET_CODE (X) == PLUS			\
-      && REG_P (XEXP (X, 0))			\
-      && REG_OK_FOR_BASE_P (XEXP (X, 0))	\
-      && CONSTANT_ADDRESS_P (XEXP (X, 1)))	\
-    goto ADDR;					\
+      && REG_P (XEXP (X, 0)))			\
+    {						\
+      if (REG_OK_FP_BASE_P (XEXP (X, 0)))	\
+	goto ADDR;				\
+      if (REG_OK_FOR_BASE_P (XEXP (X, 0))	\
+	  && CONSTANT_ADDRESS_P (XEXP (X, 1)))	\
+	goto ADDR;				\
+    }						\
 }
 
 /* Now accept the simple address, or, for DImode only, an AND of a simple
diff --git a/gcc/config/alpha/alpha.md b/gcc/config/alpha/alpha.md
index ab56951..5014437 100644
--- a/gcc/config/alpha/alpha.md
+++ b/gcc/config/alpha/alpha.md
@@ -563,14 +563,28 @@
   return pattern[which];
 }")
 
-;; Don't do this if we are adjusting SP since we don't want to do
-;; it in two steps. 
+;; ??? Allow large constants when basing off the frame pointer or some
+;; virtual register that may eliminate to the frame pointer.  This is
+;; done because register elimination offsets will change the hi/lo split,
+;; and if we split before reload, we will require additional instructions.
+
+(define_insn ""
+  [(set (match_operand:DI 0 "register_operand" "=r")
+        (plus:DI (match_operand:DI 1 "reg_no_subreg_operand" "r")
+		 (match_operand:DI 2 "const_int_operand" "n")))]
+  "REG_OK_FP_BASE_P (operands[1])"
+  "#")
+
+;; Don't do this if we are adjusting SP since we don't want to do it
+;; in two steps.  Don't split FP sources for the reason listed above.
 (define_split
   [(set (match_operand:DI 0 "register_operand" "")
 	(plus:DI (match_operand:DI 1 "register_operand" "")
 		 (match_operand:DI 2 "const_int_operand" "")))]
   "! add_operand (operands[2], DImode)
-   && operands[0] != stack_pointer_rtx"
+   && operands[0] != stack_pointer_rtx
+   && operands[1] != frame_pointer_rtx
+   && operands[1] != arg_pointer_rtx"
   [(set (match_dup 0) (plus:DI (match_dup 1) (match_dup 3)))
    (set (match_dup 0) (plus:DI (match_dup 0) (match_dup 4)))]
   "