sh.h (LOAD_EXTEND_OP): QImode zero-extends on SHmedia.

	* sh.h (LOAD_EXTEND_OP): QImode zero-extends on SHmedia.
	* sh.md (truncdiqi2, movqi_media): Likewise.

From-SVN: r55757

gcc/ChangeLog

+Thu Jul 25 20:34:50 2002  J"orn Rennecke <joern.rennecke@superh.com>
+
+	* sh.h (LOAD_EXTEND_OP): QImode zero-extends on SHmedia.
+	* sh.md (truncdiqi2, movqi_media): Likewise.
+
 2002-07-25  Neil Booth  <neil@daikokuya.co.uk>
 
 	* gcse.c (obstack_chunk_alloc): Remove.

gcc/config/sh/sh.h

@@ -2623,9 +2623,12 @@ while (0)
    will either zero-extend or sign-extend.  The value of this macro should
    be the code that says which one of the two operations is implicitly
    done, NIL if none.  */
+/* For SHmedia, we can truncate to QImode easier using zero extension.  */
 /* FP registers can load SImode values, but don't implicitly sign-extend
    them to DImode.  */
-#define LOAD_EXTEND_OP(MODE) ((MODE) != SImode ? SIGN_EXTEND : NIL)
+#define LOAD_EXTEND_OP(MODE) \
+ (((MODE) == QImode  && TARGET_SHMEDIA) ? ZERO_EXTEND \
+  : (MODE) != SImode ? SIGN_EXTEND : NIL)
 
 /* Define if loading short immediate values into registers sign extends.  */
 #define SHORT_IMMEDIATES_SIGN_EXTEND

gcc/config/sh/sh.md

@@ -3382,17 +3382,15 @@
   [(set_attr "type"   "arith_media,store_media")
    (set_attr "length" "8,4")])
 
-; N.B. we want sign-extension here because
-; - we need to be consistent with LOAD_EXTEND_OP and movqi
-; - only sign extension allows us to do signed compares transparently.
-;  unsigned compares don't care about the kind of extension as long as
-;   it's consistent.
+; N.B. This should agree with LOAD_EXTEND_OP and movqi.
+; Because we use zero extension, we can't provide signed QImode compares
+; using a simple compare or conditional banch insn.
 (define_insn "truncdiqi2"
   [(set (match_operand:QI 0 "general_movdst_operand" "=r,m")
 	(truncate:QI (match_operand:DI 1 "register_operand" "r,r")))]
   "TARGET_SHMEDIA"
   "@
-	ori	%1, -256, %0
+	and	%1, 255, %0
 	st%M0.b	%m0, %1"
   [(set_attr "type"   "arith_media,store")])
 
@@ -3741,7 +3739,7 @@
   "@
 	add.l	%1, r63, %0
 	movi	%1, %0
-	ld%M1.b	%m1, %0
+	ld%M1.ub	%m1, %0
 	st%M0.b	%m0, %1"
   [(set_attr "type" "arith_media,arith_media,load_media,store_media")])