explow.c (trunc_int_for_mode): New function.

        * explow.c (trunc_int_for_mode): New function.
        (plus_constant_wide): Use it.
        * combine.c (simplify_and_const_int): Likewise.
        (merge_outer_ops): Likewise.
        (simplify_shift_const): Likewise.
        * cse.c (simplify_unary_operation): Likewise.
        (simplify_binary_operation): Likewise.
        * emit-rtl.c (operand_subword): Likewise.
        * rtl.h: Declare it.

From-SVN: r28222

1 files changed, 3 insertions, 62 deletions

diff --git a/gcc/cse.c b/gcc/cse.c
index 605d185..edd434b 100644
--- a/gcc/cse.c
+++ b/gcc/cse.c
@@ -3364,27 +3364,7 @@ simplify_unary_operation (code, mode, op, op_mode)
 	  abort ();
 	}
 
-      /* Clear the bits that don't belong in our mode,
-	 unless they and our sign bit are all one.
-	 So we get either a reasonable negative value or a reasonable
-	 unsigned value for this mode.  */
-      if (width < HOST_BITS_PER_WIDE_INT
-	  && ((val & ((HOST_WIDE_INT) (-1) << (width - 1)))
-	      != ((HOST_WIDE_INT) (-1) << (width - 1))))
-	val &= ((HOST_WIDE_INT) 1 << width) - 1;
-
-      /* If this would be an entire word for the target, but is not for
-	 the host, then sign-extend on the host so that the number will look
-	 the same way on the host that it would on the target.
-
-	 For example, when building a 64 bit alpha hosted 32 bit sparc
-	 targeted compiler, then we want the 32 bit unsigned value -1 to be
-	 represented as a 64 bit value -1, and not as 0x00000000ffffffff.
-	 The later confuses the sparc backend.  */
-
-      if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width
-	  && (val & ((HOST_WIDE_INT) 1 << (width - 1))))
-	val |= ((HOST_WIDE_INT) (-1) << width);
+      val = trunc_int_for_mode (val, mode);
 
       return GEN_INT (val);
     }
@@ -3556,27 +3536,7 @@ simplify_unary_operation (code, mode, op, op_mode)
 
       set_float_handler (NULL_PTR);
 
-      /* Clear the bits that don't belong in our mode,
-	 unless they and our sign bit are all one.
-	 So we get either a reasonable negative value or a reasonable
-	 unsigned value for this mode.  */
-      if (width < HOST_BITS_PER_WIDE_INT
-	  && ((val & ((HOST_WIDE_INT) (-1) << (width - 1)))
-	      != ((HOST_WIDE_INT) (-1) << (width - 1))))
-	val &= ((HOST_WIDE_INT) 1 << width) - 1;
-
-      /* If this would be an entire word for the target, but is not for
-	 the host, then sign-extend on the host so that the number will look
-	 the same way on the host that it would on the target.
-
-	 For example, when building a 64 bit alpha hosted 32 bit sparc
-	 targeted compiler, then we want the 32 bit unsigned value -1 to be
-	 represented as a 64 bit value -1, and not as 0x00000000ffffffff.
-	 The later confuses the sparc backend.  */
-
-      if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width
-	  && (val & ((HOST_WIDE_INT) 1 << (width - 1))))
-	val |= ((HOST_WIDE_INT) (-1) << width);
+      val = trunc_int_for_mode (val, mode);
 
       return GEN_INT (val);
     }
@@ -4458,26 +4418,7 @@ simplify_binary_operation (code, mode, op0, op1)
       abort ();
     }
 
-  /* Clear the bits that don't belong in our mode, unless they and our sign
-     bit are all one.  So we get either a reasonable negative value or a
-     reasonable unsigned value for this mode.  */
-  if (width < HOST_BITS_PER_WIDE_INT
-      && ((val & ((HOST_WIDE_INT) (-1) << (width - 1)))
-	  != ((HOST_WIDE_INT) (-1) << (width - 1))))
-    val &= ((HOST_WIDE_INT) 1 << width) - 1;
-
-  /* If this would be an entire word for the target, but is not for
-     the host, then sign-extend on the host so that the number will look
-     the same way on the host that it would on the target.
-
-     For example, when building a 64 bit alpha hosted 32 bit sparc
-     targeted compiler, then we want the 32 bit unsigned value -1 to be
-     represented as a 64 bit value -1, and not as 0x00000000ffffffff.
-     The later confuses the sparc backend.  */
-
-  if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width
-      && (val & ((HOST_WIDE_INT) 1 << (width - 1))))
-    val |= ((HOST_WIDE_INT) (-1) << width);
+  val = trunc_int_for_mode (val, mode);
 
   return GEN_INT (val);
 }