sh.c (gen_ashift_hi): Implement right shifts via gen_ashift.

	* sh.c (gen_ashift_hi): Implement right shifts via gen_ashift.
	* sh.md (ashrhi3_k, lshrhi3_k, lshrhi3_m, lshrhi3, lshrhi3+1): Delete.

From-SVN: r19385

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f6d49dbe0ed1ed748aa7e8a1cb1b33d88941400d..126e635dc7277036ef06674b7f33a5e79f21e164 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+Thu Apr 23 20:21:06 1997  J"orn Rennecke <amylaar@cygnus.co.uk>
+
+       * sh.c (gen_ashift_hi): Implement right shifts via gen_ashift.
+       * sh.md (ashrhi3_k, lshrhi3_k, lshrhi3_m, lshrhi3, lshrhi3+1): Delete.
+
 Wed Apr 22 17:07:35 1998  Michael Meissner  <meissner@cygnus.com>
 
        * loop.c (note_addr_stored): Correct function to take 2 arguments,

diff --git a/gcc/config/sh/sh.c b/gcc/config/sh/sh.c
index 0c4231345c5fc67621005ac59b3f256662a1eecd..447716cb763bc39f19a2f7f7f84c56f693853c39 100644 (file)
--- a/gcc/config/sh/sh.c
+++ b/gcc/config/sh/sh.c
@@ -916,13 +916,13 @@ gen_ashift_hi (type, n, reg)
   switch (type)
     {
     case ASHIFTRT:
-      emit_insn (gen_ashrhi3_k (reg, reg, GEN_INT (n)));
-      break;
     case LSHIFTRT:
-      if (n == 1)
-       emit_insn (gen_lshrhi3_m (reg, reg, GEN_INT (n)));
-      else
-       emit_insn (gen_lshrhi3_k (reg, reg, GEN_INT (n)));
+      /* We don't have HImode right shift operations because using the
+        ordinary 32 bit shift instructions for that doesn't generate proper
+        zero/sign extension.
+        gen_ashift_hi is only called in contexts where we know that the
+        sign extension works out correctly.  */
+      gen_ashift (type, n, gen_rtx_SUBREG (SImode, reg, 0));
       break;
     case ASHIFT:
       emit_insn (gen_ashlhi3_k (reg, reg, GEN_INT (n)));

diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index 8659ddc75a47292eb3d62283b00141dde4d9f608..e25f2b72c6afb88a7a2c80ecf31f05b083557a22 100644 (file)
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -1208,14 +1208,11 @@
   "shar        %0"
   [(set_attr "type" "arith")])
 
-(define_insn "ashrhi3_k"
-  [(set (match_operand:HI 0 "arith_reg_operand" "=r")
-       (ashiftrt:HI (match_operand:HI 1 "arith_reg_operand" "0")
-                    (match_operand:HI 2 "const_int_operand" "M")))
-   (clobber (reg:SI 18))]
-  "INTVAL (operands[2]) == 1"
-  "shar        %0"
-  [(set_attr "type" "arith")])
+;; We can't do HImode right shifts correctly unless we start out with an
+;; explicit zero / sign extension; doing that would result in worse overall
+;; code, so just let the machine independent code widen the mode.
+;; That's why we don't have ashrhi3_k / lshrhi3_k / lshrhi3_m / lshrhi3 .
+
 
 ;; ??? This should be a define expand.
 
@@ -1328,24 +1325,6 @@
   "shlr%O2     %0"
   [(set_attr "type" "arith")])
 
-(define_insn "lshrhi3_m"
-  [(set (match_operand:HI 0 "arith_reg_operand" "=r")
-       (lshiftrt:HI (match_operand:HI 1 "arith_reg_operand" "0")
-                    (match_operand:HI 2 "const_int_operand" "M")))
-   (clobber (reg:SI 18))]
-  "CONST_OK_FOR_M (INTVAL (operands[2]))"
-  "shlr        %0"
-  [(set_attr "type" "arith")])
-
-(define_insn "lshrhi3_k"
-  [(set (match_operand:HI 0 "arith_reg_operand" "=r")
-       (lshiftrt:HI (match_operand:HI 1 "arith_reg_operand" "0")
-                    (match_operand:HI 2 "const_int_operand" "K")))]
-  "CONST_OK_FOR_K (INTVAL (operands[2]))
-   && ! CONST_OK_FOR_M (INTVAL (operands[2]))"
-  "shlr%O2     %0"
-  [(set_attr "type" "arith")])
-
 (define_insn "lshrsi3_n"
   [(set (match_operand:SI 0 "arith_reg_operand" "=r")
        (lshiftrt:SI (match_operand:SI 1 "arith_reg_operand" "0")
@@ -1398,35 +1377,6 @@
     FAIL;
 }")
 
-(define_insn "lshrhi3"
-  [(set (match_operand:HI 0 "arith_reg_operand" "=r")
-       (lshiftrt:HI (match_operand:HI 1 "arith_reg_operand" "0")
-                    (match_operand:HI 2 "const_int_operand" "n")))
-   (clobber (reg:SI 18))]
-  ""
-  "#"
-;; ??? length attribute is sometimes six instead of four.
-  [(set (attr "length")
-       (cond [(eq (symbol_ref "shift_insns_rtx (insn)") (const_int 1))
-              (const_string "2")
-              (eq (symbol_ref "shift_insns_rtx (insn)") (const_int 2))
-              (const_string "4")]
-             (const_string "6")))
-   (set_attr "type" "arith")])
-
-(define_split
-  [(set (match_operand:HI 0 "arith_reg_operand" "")
-       (lshiftrt:HI (match_operand:HI 1 "arith_reg_operand" "")
-                    (match_operand:HI 2 "const_int_operand" "n")))
-   (clobber (reg:SI 18))]
-  ""
-  [(use (reg:SI 0))]
-  "
-{
-  gen_shifty_hi_op (LSHIFTRT, operands);
-  DONE;
-}")
-
 ;; ??? This should be a define expand.
 
 (define_insn "ashldi3_k"