sh.md (setmemqi): New expand pattern.

2014-04-14  Christian Bruel  <christian.bruel@st.com>

       * config/sh/sh.md (setmemqi): New expand pattern.
       * config/sh/sh.h (CLEAR_RATIO): Define.
       * config/sh/sh-mem.cc (sh_expand_setmem): Define.
       * config/sh/sh-protos.h (sh_expand_setmem): Declare.

From-SVN: r209357

4 files changed, 123 insertions, 0 deletions

diff --git a/gcc/config/sh/sh-mem.cc b/gcc/config/sh/sh-mem.cc
index 45af23a..d499b3b 100644
--- a/gcc/config/sh/sh-mem.cc
+++ b/gcc/config/sh/sh-mem.cc
@@ -608,3 +608,106 @@ sh_expand_strlen (rtx *operands)
 
   return true;
 }
+
+/* Emit code to perform a memset
+
+   OPERANDS[0] is the destination.
+   OPERANDS[1] is the size;
+   OPERANDS[2] is the char to search.
+   OPERANDS[3] is the alignment.  */
+void
+sh_expand_setmem (rtx *operands)
+{
+  rtx L_loop_byte = gen_label_rtx ();
+  rtx L_loop_word = gen_label_rtx ();
+  rtx L_return = gen_label_rtx ();
+  rtx jump;
+  rtx dest = copy_rtx (operands[0]);
+  rtx dest_addr = copy_addr_to_reg (XEXP (dest, 0));
+  rtx val = force_reg (SImode, operands[2]);
+  int align = INTVAL (operands[3]);
+  int count = 0;
+  rtx len = force_reg (SImode, operands[1]);
+
+  if (! CONST_INT_P (operands[1]))
+    return;
+
+  count = INTVAL (operands[1]);
+
+  if (CONST_INT_P (operands[2])
+      && (INTVAL (operands[2]) == 0 || INTVAL (operands[2]) == -1) && count > 8)
+    {
+      rtx lenw = gen_reg_rtx (SImode);
+
+      if (align < 4)
+        {
+          emit_insn (gen_tstsi_t (GEN_INT (3), dest_addr));
+          jump = emit_jump_insn (gen_branch_false (L_loop_byte));
+          add_int_reg_note (jump, REG_BR_PROB, prob_likely);
+        }
+
+      /* word count. Do we have iterations ? */
+      emit_insn (gen_lshrsi3 (lenw, len, GEN_INT (2)));
+
+      dest = adjust_automodify_address (dest, SImode, dest_addr, 0);
+
+      /* start loop.  */
+      emit_label (L_loop_word);
+
+      if (TARGET_SH2)
+        emit_insn (gen_dect (lenw, lenw));
+      else
+        {
+          emit_insn (gen_addsi3 (lenw, lenw, GEN_INT (-1)));
+          emit_insn (gen_tstsi_t (lenw, lenw));
+        }
+
+      emit_move_insn (dest, val);
+      emit_move_insn (dest_addr, plus_constant (Pmode, dest_addr,
+                                                GET_MODE_SIZE (SImode)));
+
+
+      jump = emit_jump_insn (gen_branch_false (L_loop_word));
+      add_int_reg_note (jump, REG_BR_PROB, prob_likely);
+      count = count % 4;
+
+      dest = adjust_address (dest, QImode, 0);
+
+      val = gen_lowpart (QImode, val);
+
+      while (count--)
+        {
+          emit_move_insn (dest, val);
+          emit_move_insn (dest_addr, plus_constant (Pmode, dest_addr,
+                                                    GET_MODE_SIZE (QImode)));
+        }
+
+      jump = emit_jump_insn (gen_jump_compact (L_return));
+      emit_barrier_after (jump);
+    }
+
+  dest = adjust_automodify_address (dest, QImode, dest_addr, 0);
+
+  /* start loop.  */
+  emit_label (L_loop_byte);
+
+  if (TARGET_SH2)
+    emit_insn (gen_dect (len, len));
+  else
+    {
+      emit_insn (gen_addsi3 (len, len, GEN_INT (-1)));
+      emit_insn (gen_tstsi_t (len, len));
+    }
+
+  val = gen_lowpart (QImode, val);
+  emit_move_insn (dest, val);
+  emit_move_insn (dest_addr, plus_constant (Pmode, dest_addr,
+                                            GET_MODE_SIZE (QImode)));
+
+  jump = emit_jump_insn (gen_branch_false (L_loop_byte));
+  add_int_reg_note (jump, REG_BR_PROB, prob_likely);
+
+  emit_label (L_return);
+
+  return;
+}
diff --git a/gcc/config/sh/sh-protos.h b/gcc/config/sh/sh-protos.h
index defc76a..685cd23 100644
--- a/gcc/config/sh/sh-protos.h
+++ b/gcc/config/sh/sh-protos.h
@@ -119,6 +119,7 @@ extern void prepare_move_operands (rtx[], enum machine_mode mode);
 extern bool sh_expand_cmpstr (rtx *);
 extern bool sh_expand_cmpnstr (rtx *);
 extern bool sh_expand_strlen  (rtx *);
+extern void sh_expand_setmem (rtx *);
 extern enum rtx_code prepare_cbranch_operands (rtx *, enum machine_mode mode,
 					       enum rtx_code comparison);
 extern void expand_cbranchsi4 (rtx *operands, enum rtx_code comparison, int);
diff --git a/gcc/config/sh/sh.h b/gcc/config/sh/sh.h
index 8819300..8c30e5c 100644
--- a/gcc/config/sh/sh.h
+++ b/gcc/config/sh/sh.h
@@ -1594,6 +1594,11 @@ struct sh_args {
 
 #define SET_BY_PIECES_P(SIZE, ALIGN) STORE_BY_PIECES_P(SIZE, ALIGN)
 
+/* If a memory clear move would take CLEAR_RATIO or more simple
+   move-instruction pairs, we will do a setmem instead.  */
+
+#define CLEAR_RATIO(speed) ((speed) ? 15 : 3)
+
 /* Macros to check register numbers against specific register classes.  */
 
 /* These assume that REGNO is a hard or pseudo reg number.
diff --git a/gcc/config/sh/sh.md b/gcc/config/sh/sh.md
index ab1f0a5..9035bfc 100644
--- a/gcc/config/sh/sh.md
+++ b/gcc/config/sh/sh.md
@@ -12089,6 +12089,20 @@ label:
    FAIL;
 })
 
+(define_expand "setmemqi"
+  [(parallel [(set (match_operand:BLK 0 "memory_operand")
+                   (match_operand 2 "const_int_operand"))
+              (use (match_operand:QI 1 "const_int_operand"))
+              (use (match_operand:QI 3 "const_int_operand"))])]
+  "TARGET_SH1 && optimize"
+  {
+    if (optimize_insn_for_size_p ())
+       FAIL;
+
+    sh_expand_setmem (operands);
+    DONE;
+  })
+
 
 ;; -------------------------------------------------------------------------
 ;; Floating point instructions.