gcc/

	* simplify-rtx.c (simplify_binary_operation_1): Canonicalize
	truncated shift counts.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@129072 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index db4a7d0..7562e40 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2007-10-07  Richard Sandiford  <rsandifo@nildram.co.uk>
+
+       * simplify-rtx.c (simplify_binary_operation_1): Canonicalize
+       truncated shift counts.
+
 2007-10-07  Kazu Hirata  <kazu@codesourcery.com>
 
        * config/m68k/m68k.c, config/m68k/m68k.md: Use the assembly

diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 8e02612..0371339 100644 (file)
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -2562,6 +2562,13 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
          && (unsigned HOST_WIDE_INT) INTVAL (trueop0) == GET_MODE_MASK (mode)
          && ! side_effects_p (op1))
        return op0;
+    canonicalize_shift:
+      if (SHIFT_COUNT_TRUNCATED && GET_CODE (op1) == CONST_INT)
+       {
+         val = INTVAL (op1) & (GET_MODE_BITSIZE (mode) - 1);
+         if (val != INTVAL (op1))
+           return simplify_gen_binary (code, mode, op0, GEN_INT (val));
+       }
       break;
 
     case ASHIFT:
@@ -2571,7 +2578,7 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
        return op0;
       if (trueop0 == CONST0_RTX (mode) && ! side_effects_p (op1))
        return op0;
-      break;
+      goto canonicalize_shift;
 
     case LSHIFTRT:
       if (trueop1 == CONST0_RTX (mode))
@@ -2593,7 +2600,7 @@ simplify_binary_operation_1 (enum rtx_code code, enum machine_mode mode,
            return simplify_gen_relational (EQ, mode, imode,
                                            XEXP (op0, 0), const0_rtx);
        }
-      break;
+      goto canonicalize_shift;
 
     case SMIN:
       if (width <= HOST_BITS_PER_WIDE_INT