This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: IVOPT improvement patch


Wrong patch in the last email. Here is the one.

David

On Mon, Aug 9, 2010 at 3:54 PM, Xinliang David Li <davidxl@google.com> wrote:
> You are right. The attached is the revised version. ?Ok this time
> (after testing is done)?
>
> Thanks,
>
> David
>
> On Mon, Aug 9, 2010 at 12:55 AM, Zdenek Dvorak <rakdver@kam.mff.cuni.cz> wrote:
>> Hi,
>>
>>> Compiler bootstrapped and tested with Lu's patch (with one minor
>>> change to initialize off variable) (x86-64/linux) -- also checked dump
>>> file that offsets are properly computed.
>>
>> in case that no offsets are allowed (or more hypotetically, if only offsets of
>> +1 or -1 are allowed), the code below will set min_offset to -2 and max_offset
>> to +2, thus incorrectly extending the range of allowed offsets.
>>
>> Zdenek
>>
>>> ? ? ? ?reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1);
>>>
>>> + ? ? ?width = GET_MODE_BITSIZE (address_mode) - 1;
>>> + ? ? ?if (width > (HOST_BITS_PER_WIDE_INT - 1))
>>> + ? ? width = HOST_BITS_PER_WIDE_INT - 1;
>>> ? ? ? ?addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX);
>>> - ? ? ?for (i = start; i <= 1 << 20; i <<= 1)
>>> +
>>> + ? ? ?for (i = width; i; i--)
>>> ? ? ? {
>>> - ? ? ? XEXP (addr, 1) = gen_int_mode (i, address_mode);
>>> - ? ? ? if (!memory_address_addr_space_p (mem_mode, addr, as))
>>> + ? ? ? off = -((HOST_WIDE_INT) 1 << i);
>>> + ? ? ? XEXP (addr, 1) = gen_int_mode (off, address_mode);
>>> + ? ? ? if (memory_address_addr_space_p (mem_mode, addr, as))
>>> ? ? ? ? ? break;
>>> ? ? ? }
>>> - ? ? ?data->max_offset = i == start ? 0 : i >> 1;
>>> - ? ? ?off = data->max_offset;
>>> + ? ? ?data->min_offset = off;
>>>
>>> - ? ? ?for (i = start; i <= 1 << 20; i <<= 1)
>>> + ? ? ?for (i = width; i; i--)
>>> ? ? ? {
>>> - ? ? ? XEXP (addr, 1) = gen_int_mode (-i, address_mode);
>>> - ? ? ? if (!memory_address_addr_space_p (mem_mode, addr, as))
>>> + ? ? ? off = ((HOST_WIDE_INT) 1 << i) - 1;
>>> + ? ? ? XEXP (addr, 1) = gen_int_mode (off, address_mode);
>>> + ? ? ? if (memory_address_addr_space_p (mem_mode, addr, as))
>>> ? ? ? ? ? break;
>>> ? ? ? }
>>> - ? ? ?data->min_offset = i == start ? 0 : -(i >> 1);
>>> + ? ? ?data->max_offset = off;
>>>
>>> ? ? ? ?if (dump_file && (dump_flags & TDF_DETAILS))
>>> ? ? ? {
>>> ? ? ? ? fprintf (dump_file, "get_address_cost:\n");
>>> - ? ? ? fprintf (dump_file, " ?min offset %s %d\n",
>>> + ? ? ? fprintf (dump_file, " ?min offset %s " HOST_WIDE_INT_PRINT_DEC "\n",
>>> ? ? ? ? ? ? ? ? ?GET_MODE_NAME (mem_mode),
>>> - ? ? ? ? ? ? ? ?(int) data->min_offset);
>>> - ? ? ? fprintf (dump_file, " ?max offset %s %d\n",
>>> + ? ? ? ? ? ? ? ?data->min_offset);
>>> + ? ? ? fprintf (dump_file, " ?max offset %s " HOST_WIDE_INT_PRINT_DEC "\n",
>>> ? ? ? ? ? ? ? ? ?GET_MODE_NAME (mem_mode),
>>> - ? ? ? ? ? ? ? ?(int) data->max_offset);
>>> + ? ? ? ? ? ? ? ?data->max_offset);
>>> ? ? ? }
>>>
>>> ? ? ? ?rat = 1;
>>
>>
>
Index: gcc/tree-ssa-loop-ivopts.c
===================================================================
--- gcc/tree-ssa-loop-ivopts.c	(revision 162822)
+++ gcc/tree-ssa-loop-ivopts.c	(working copy)
@@ -3241,9 +3241,8 @@ get_address_cost (bool symbol_present, b
   if (!data)
     {
       HOST_WIDE_INT i;
-      HOST_WIDE_INT start = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
-      HOST_WIDE_INT rat, off;
-      int old_cse_not_expected;
+      HOST_WIDE_INT rat, off = 0;
+      int old_cse_not_expected, width;
       unsigned sym_p, var_p, off_p, rat_p, add_c;
       rtx seq, addr, base;
       rtx reg0, reg1;
@@ -3252,33 +3251,39 @@ get_address_cost (bool symbol_present, b
 
       reg1 = gen_raw_REG (address_mode, LAST_VIRTUAL_REGISTER + 1);
 
+      width = GET_MODE_BITSIZE (address_mode) - 1;
+      if (width > (HOST_BITS_PER_WIDE_INT - 1))
+	width = HOST_BITS_PER_WIDE_INT - 1;
       addr = gen_rtx_fmt_ee (PLUS, address_mode, reg1, NULL_RTX);
-      for (i = start; i <= 1 << 20; i <<= 1)
+
+      for (i = width; i >= 0; i--)
 	{
-	  XEXP (addr, 1) = gen_int_mode (i, address_mode);
-	  if (!memory_address_addr_space_p (mem_mode, addr, as))
+	  off = -((HOST_WIDE_INT) 1 << i);
+	  XEXP (addr, 1) = gen_int_mode (off, address_mode);
+	  if (memory_address_addr_space_p (mem_mode, addr, as))
 	    break;
 	}
-      data->max_offset = i == start ? 0 : i >> 1;
-      off = data->max_offset;
+      data->min_offset = (i == -1? 0 : off);
 
-      for (i = start; i <= 1 << 20; i <<= 1)
+      for (i = width; i >= 0; i--)
 	{
-	  XEXP (addr, 1) = gen_int_mode (-i, address_mode);
-	  if (!memory_address_addr_space_p (mem_mode, addr, as))
+	  off = ((HOST_WIDE_INT) 1 << i) - 1;
+	  XEXP (addr, 1) = gen_int_mode (off, address_mode);
+	  if (memory_address_addr_space_p (mem_mode, addr, as))
 	    break;
 	}
-      data->min_offset = i == start ? 0 : -(i >> 1);
+      data->max_offset = (i == -1? 0 : off);
+      offset = data->max_offset;
 
       if (dump_file && (dump_flags & TDF_DETAILS))
 	{
 	  fprintf (dump_file, "get_address_cost:\n");
-	  fprintf (dump_file, "  min offset %s %d\n",
+	  fprintf (dump_file, "  min offset %s " HOST_WIDE_INT_PRINT_DEC "\n",
 		   GET_MODE_NAME (mem_mode),
-		   (int) data->min_offset);
-	  fprintf (dump_file, "  max offset %s %d\n",
+		   data->min_offset);
+	  fprintf (dump_file, "  max offset %s " HOST_WIDE_INT_PRINT_DEC "\n",
 		   GET_MODE_NAME (mem_mode),
-		   (int) data->max_offset);
+		   data->max_offset);
 	}
 
       rat = 1;

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]