arm.c (arm_reload_in_hi): Ensure that the scratch register does not overlap the…

arm.c (arm_reload_in_hi): Ensure that the scratch register does not overlap the final result register.

* arm.c (arm_reload_in_hi): Ensure that the scratch register does
not overlap the final result register.

From-SVN: r62981

gcc/ChangeLog

+2003-02-16 Richard Earnshaw  <rearnsha@arm.com>
+
+	* arm.c (arm_reload_in_hi): Ensure that the scratch register does
+	not overlap the final result register.
+
 2003-02-16 Arend Bayer <arend.bayer@web.de>
 	   Richard Henderson  <rth@redhat.com>
 

gcc/config/arm/arm.c

@@ -5845,7 +5845,14 @@ arm_reload_in_hi (operands)
 	}
     }
 
-  scratch = gen_rtx_REG (SImode, REGNO (operands[2]));
+  /* Operands[2] may overlap operands[0] (though it won't overlap
+     operands[1]), that's why we asked for a DImode reg -- so we can
+     use the bit that does not overlap.  */
+  if (REGNO (operands[2]) == REGNO (operands[0]))
+    scratch = gen_rtx_REG (SImode, REGNO (operands[2]) + 1);
+  else
+    scratch = gen_rtx_REG (SImode, REGNO (operands[2]));
+
   emit_insn (gen_zero_extendqisi2 (scratch,
 				   gen_rtx_MEM (QImode,
 						plus_constant (base,