PR target/21017

	* combine.c (simplify_logical <IOR>): Simplify more patterns to
	rotates.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@107873 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index d33807b..44052d0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,11 @@
 2005-12-02  Alan Modra  <amodra@bigpond.net.au>
 
+       PR target/21017
+       * combine.c (simplify_logical <IOR>): Simplify more patterns to
+       rotates.
+
+2005-12-02  Alan Modra  <amodra@bigpond.net.au>
+
        PR middle-end/25176
        * function.c (expand_function_end): Emit blockage for unwinder
        after return label.

diff --git a/gcc/combine.c b/gcc/combine.c
index 08cacab..b13ea86 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -5597,7 +5597,7 @@ simplify_logical (rtx x)
   enum machine_mode mode = GET_MODE (x);
   rtx op0 = XEXP (x, 0);
   rtx op1 = XEXP (x, 1);
-  rtx reversed;
+  rtx tmp, reversed;
 
   switch (GET_CODE (x))
     {
@@ -5724,16 +5724,37 @@ simplify_logical (rtx x)
       /* Convert (ior (ashift A CX) (lshiftrt A CY)) where CX+CY equals the
         mode size to (rotate A CX).  */
 
-      if (((GET_CODE (op0) == ASHIFT && GET_CODE (op1) == LSHIFTRT)
-          || (GET_CODE (op1) == ASHIFT && GET_CODE (op0) == LSHIFTRT))
+      if (GET_CODE (op1) == ASHIFT
+         || GET_CODE (op1) == SUBREG)
+       tmp = op1, op1 = op0, op0 = tmp;
+
+      if (GET_CODE (op0) == ASHIFT && GET_CODE (op1) == LSHIFTRT
          && rtx_equal_p (XEXP (op0, 0), XEXP (op1, 0))
          && GET_CODE (XEXP (op0, 1)) == CONST_INT
          && GET_CODE (XEXP (op1, 1)) == CONST_INT
          && (INTVAL (XEXP (op0, 1)) + INTVAL (XEXP (op1, 1))
              == GET_MODE_BITSIZE (mode)))
-       return gen_rtx_ROTATE (mode, XEXP (op0, 0),
-                              (GET_CODE (op0) == ASHIFT
-                               ? XEXP (op0, 1) : XEXP (op1, 1)));
+       return gen_rtx_ROTATE (mode, XEXP (op1, 0), XEXP (op0, 1));
+
+      /* Same, but for ashift that has been "simplified" to a wider mode
+        by simplify_shift_const.  */
+
+      if (GET_CODE (op0) == SUBREG
+         && GET_CODE (SUBREG_REG (op0)) == ASHIFT
+         && GET_CODE (op1) == LSHIFTRT
+         && GET_CODE (XEXP (op1, 0)) == SUBREG
+         && GET_MODE (op0) == GET_MODE (XEXP (op1, 0))
+         && SUBREG_BYTE (op0) == SUBREG_BYTE (XEXP (op1, 0))
+         && (GET_MODE_SIZE (GET_MODE (op0))
+             < GET_MODE_SIZE (GET_MODE (SUBREG_REG (op0))))
+         && rtx_equal_p (XEXP (SUBREG_REG (op0), 0),
+                         SUBREG_REG (XEXP (op1, 0)))
+         && GET_CODE (XEXP (SUBREG_REG (op0), 1)) == CONST_INT
+         && GET_CODE (XEXP (op1, 1)) == CONST_INT
+         && (INTVAL (XEXP (SUBREG_REG (op0), 1)) + INTVAL (XEXP (op1, 1))
+             == GET_MODE_BITSIZE (mode)))
+       return gen_rtx_ROTATE (mode, XEXP (op1, 0),
+                              XEXP (SUBREG_REG (op0), 1));
 
       /* If OP0 is (ashiftrt (plus ...) C), it might actually be
         a (sign_extend (plus ...)).  If so, OP1 is a CONST_INT, and the PLUS