* h8300.c (split_adds_subs): Rearrange code for conciseness.

From-SVN: r35371

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index adb56754de968095f7b23d83e2718c3be1198d68..d1d5440c61f183e849420ee15ad1d32b13927411 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2000-07-31  Kazu Hirata  <kazu@hxi.com>
+
+       * h8300.c (split_adds_subs): Rearrange code for conciseness.
+
 Mon Jul 31 12:27:55 MET DST 2000  Jan Hubicka  <jh@suse.cz>
 
        * i386.md (addsi to lea splitter, ashlqi3_1_lea): Fix bugs

diff --git a/gcc/config/h8300/h8300.c b/gcc/config/h8300/h8300.c
index 5c404eb1f986e6599e65c1d8e4646f7d4e92fab3..7cb293eb08b2a274cc1446f3d6a50ada0e3d8e37 100644 (file)
--- a/gcc/config/h8300/h8300.c
+++ b/gcc/config/h8300/h8300.c
@@ -682,61 +682,31 @@ split_adds_subs (mode, operands)
 {
   HOST_WIDE_INT val = INTVAL (operands[1]);
   rtx reg = operands[0];
-  rtx tmp;
+  HOST_WIDE_INT sign = 1;
+  HOST_WIDE_INT amount;
 
-  /* Take care of +/- 4 for H8300H and H8300S.  */
-  if (TARGET_H8300H || TARGET_H8300S)
+  /* Force VAL to be positive so that we do not have to consider the
+     sign.  */
+  if (val < 0)
     {
-      /* Get the value in range of +/- 4.  */
-      if (val > 4)
-       {
-         tmp = gen_rtx_PLUS (mode, reg, GEN_INT (4));
-         emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-         val -= 4;
-       }
-      else if (val < -4)
-       {
-         tmp = gen_rtx_PLUS (mode, reg, GEN_INT (-4));
-         emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-         val += 4;
-       }
+      val = -val;
+      sign = -1;
+    }
 
-      if (val == 4 || val == -4)
+  /* Try different amounts in descending order.  */
+  for (amount = (TARGET_H8300H || TARGET_H8300S) ? 4 : 2;
+       amount > 0;
+       amount /= 2)
+    {
+      while (val >= amount)
        {
-         tmp = gen_rtx_PLUS (mode, reg, GEN_INT (val));
+         rtx tmp = gen_rtx_PLUS (mode, reg, GEN_INT (sign * amount));
          emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-         return;
+         val -= amount;
        }
     }
 
-  /* Get the value in range of +/- 2.  */
-  if (val > 2)
-    {
-      tmp = gen_rtx_PLUS (mode, reg, GEN_INT (2));
-      emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-      val -= 2;
-    }
-  else if (val < -2)
-    {
-      tmp = gen_rtx_PLUS (mode, reg, GEN_INT (-2));
-      emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-      val += 2;
-    }
-
-  /* If not optimizing, we might be asked to add 0.  */
-  if (val == 0)
-    return;
-
-  /* We should have one or two now.  */
-  if (val >= -2 && val <= 2)
-    {
-      tmp = gen_rtx_PLUS (mode, reg, GEN_INT (val));
-      emit_insn (gen_rtx_SET (VOIDmode, reg, tmp));
-      return;
-    }
-
-  /* In theory, this can't happen.  */
-  abort ();
+  return;
 }
 
 /* Return true if OP is a valid call operand, and OP represents