re PR target/23436 (Insn does not satisfy its constraints (reload_cse_simplify_operands))

	PR target/23436
	* arm.c (thumb_legitimize_reload_address): New function.
	* arm-protos.h (thumb_legitimize_reload_address): Add prototype.
	* arm.h (THUMB_LEGITIMIZE_RELOAD_ADDRESS): Call it.

From-SVN: r103273

gcc/ChangeLog

+2005-08-19  Richard Earnshaw  <richard.earnshaw@arm.com>
+
+	PR target/23436
+	* arm.c (thumb_legitimize_reload_address): New function.
+	* arm-protos.h (thumb_legitimize_reload_address): Add prototype.
+	* arm.h (THUMB_LEGITIMIZE_RELOAD_ADDRESS): Call it.
+
 2005-08-19  Paul Woegerer  <paul.woegerer@nsc.com>
 
 	* config/crx/crx.c: Implement crx_decompose_address. Reject

gcc/config/arm/arm-protos.h

@@ -61,6 +61,8 @@ extern int thumb_legitimate_address_p (enum machine_mode, rtx, int);
 extern int thumb_legitimate_offset_p (enum machine_mode, HOST_WIDE_INT);
 extern rtx arm_legitimize_address (rtx, rtx, enum machine_mode);
 extern rtx thumb_legitimize_address (rtx, rtx, enum machine_mode);
+extern rtx thumb_legitimize_reload_address (rtx *, enum machine_mode, int, int,
+					    int);
 extern int arm_const_double_rtx (rtx);
 extern int neg_const_double_rtx_ok_for_fpa (rtx);
 extern enum reg_class vfp_secondary_reload_class (enum machine_mode, rtx);

gcc/config/arm/arm.c

@@ -3839,6 +3839,49 @@ thumb_legitimize_address (rtx x, rtx orig_x, enum machine_mode mode)
   return x;
 }
 
+rtx
+thumb_legitimize_reload_address(rtx *x_p,
+				enum machine_mode mode,
+				int opnum, int type,
+				int ind_levels ATTRIBUTE_UNUSED)
+{
+  rtx x = *x_p;
+  
+  if (GET_CODE (x) == PLUS
+      && GET_MODE_SIZE (mode) < 4
+      && REG_P (XEXP (x, 0))
+      && XEXP (x, 0) == stack_pointer_rtx
+      && GET_CODE (XEXP (x, 1)) == CONST_INT
+      && !thumb_legitimate_offset_p (mode, INTVAL (XEXP (x, 1))))
+    {
+      rtx orig_x = x;
+
+      x = copy_rtx (x);
+      push_reload (orig_x, NULL_RTX, x_p, NULL, MODE_BASE_REG_CLASS (mode),
+		   Pmode, VOIDmode, 0, 0, opnum, type);
+      return x;
+    }
+
+  /* If both registers are hi-regs, then it's better to reload the
+     entire expression rather than each register individually.  That
+     only requires one reload register rather than two.  */
+  if (GET_CODE (x) == PLUS
+      && REG_P (XEXP (x, 0))
+      && REG_P (XEXP (x, 1))
+      && !REG_MODE_OK_FOR_REG_BASE_P (XEXP (x, 0), mode)
+      && !REG_MODE_OK_FOR_REG_BASE_P (XEXP (x, 1), mode))
+    {
+      rtx orig_x = x;
+
+      x = copy_rtx (x);
+      push_reload (orig_x, NULL_RTX, x_p, NULL, MODE_BASE_REG_CLASS (mode),
+		   Pmode, VOIDmode, 0, 0, opnum, type);
+      return x;
+    }
+
+  return NULL;
+}
+
 
 
 #define REG_OR_SUBREG_REG(X)						\

gcc/config/arm/arm.h

@@ -1282,23 +1282,15 @@ enum reg_class
 /* We could probably achieve better results by defining PROMOTE_MODE to help
    cope with the variances between the Thumb's signed and unsigned byte and
    halfword load instructions.  */
-#define THUMB_LEGITIMIZE_RELOAD_ADDRESS(X, MODE, OPNUM, TYPE, IND_LEVELS, WIN)	\
-{									\
-  if (GET_CODE (X) == PLUS						\
-      && GET_MODE_SIZE (MODE) < 4					\
-      && GET_CODE (XEXP (X, 0)) == REG					\
-      && XEXP (X, 0) == stack_pointer_rtx				\
-      && GET_CODE (XEXP (X, 1)) == CONST_INT				\
-      && ! thumb_legitimate_offset_p (MODE, INTVAL (XEXP (X, 1))))	\
+#define THUMB_LEGITIMIZE_RELOAD_ADDRESS(X, MODE, OPNUM, TYPE, IND_L, WIN)     \
+do {									      \
+  rtx new_x = thumb_legitimize_reload_address (&X, MODE, OPNUM, TYPE, IND_L); \
+  if (new_x)								      \
     {									      \
-      rtx orig_X = X;							\
-      X = copy_rtx (X);							\
-      push_reload (orig_X, NULL_RTX, &X, NULL,				\
-		   MODE_BASE_REG_CLASS (MODE),				\
-		   Pmode, VOIDmode, 0, 0, OPNUM, TYPE);			\
+      X = new_x;							      \
       goto WIN;								      \
     }									      \
-}
+} while (0)
 
 #define LEGITIMIZE_RELOAD_ADDRESS(X, MODE, OPNUM, TYPE, IND_LEVELS, WIN)   \
   if (TARGET_ARM)							   \