OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Improve SImode shifts for H8

Browse Source 
Similar to the H8/300H patch, this improves SImode shifts for the H8/S.
It's not as big a win on the H8/S since we can shift two positions at a
time.  But that also means that we can handle more residuals with minimal
ode growth after a special shift-by-16 or shift-by-24 sequence.

I think there's more to do here, but this seemed like as good a checkpoint
as any.  Tested without regressions.

gcc/
	* config/h8300/h8300.c (shift_alg_si): Avoid loops for most SImode
	shifts on the H8/S.
	(h8300_option_override): Use loops on H8/S more often when optimizing
	for size.
	(get_shift_alg): Handle new "special" cases on H8/S.  Simplify
	accordingly.  Handle various arithmetic right shifts with special
	sequences that we couldn't handle before.
This commit is contained in:
Jeff Law 2021-08-16 22:23:30 -04:00
parent d56607c16d
commit 75a7176575
1 changed files with 53 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

69
gcc/config/h8300/h8300.c
View File

@ -248,17 +248,17 @@ static enum shift_alg shift_alg_si[2][3][32] = {
/* 16 17 18 19 20 21 22 23 */
/* 24 25 26 27 28 29 30 31 */
{ INL, INL, INL, INL, INL, INL, INL, INL,
INL, INL, INL, LOP, LOP, LOP, LOP, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, LOP, LOP,
SPC, SPC, LOP, LOP, SPC, SPC, SPC, SPC }, /* SHIFT_ASHIFT */
INL, INL, INL, INL, INL, INL, INL, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC }, /* SHIFT_ASHIFT */
{ INL, INL, INL, INL, INL, INL, INL, INL,
INL, INL, INL, LOP, LOP, LOP, LOP, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, LOP, LOP,
SPC, SPC, LOP, LOP, SPC, SPC, SPC, SPC }, /* SHIFT_LSHIFTRT */
INL, INL, INL, INL, INL, INL, INL, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC }, /* SHIFT_LSHIFTRT */
{ INL, INL, INL, INL, INL, INL, INL, INL,
INL, INL, INL, LOP, LOP, LOP, LOP, LOP,
SPC, SPC, SPC, SPC, SPC, SPC, LOP, LOP,
SPC, SPC, LOP, LOP, LOP, LOP, LOP, SPC }, /* SHIFT_ASHIFTRT */
INL, INL, INL, INL, INL, INL, INL, LOP,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC,
SPC, SPC, SPC, SPC, SPC, SPC, SPC, SPC }, /* SHIFT_ASHIFTRT */
}
};
@ -375,6 +375,36 @@ h8300_option_override (void)
/* H8S */
shift_alg_hi[H8_S][SHIFT_ASHIFTRT][14] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][11] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][12] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][13] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][14] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][22] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][23] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][26] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFT][27] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][11] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][12] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][13] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][14] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][22] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][23] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][26] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_LSHIFTRT][27] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][11] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][12] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][13] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][14] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][22] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][23] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][26] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][27] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][28] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][29] = SHIFT_LOOP;
shift_alg_si[H8_S][SHIFT_ASHIFTRT][30] = SHIFT_LOOP;
}
/* Work out a value for MOVE_RATIO. */
@ -3814,8 +3844,7 @@ get_shift_alg (enum shift_type shift_type, enum shift_mode shift_mode,
gcc_unreachable ();
}
}
else if ((TARGET_H8300H && count >= 16 && count <= 23)
|| (TARGET_H8300S && count >= 16 && count <= 21))
else if (count >= 16 && count <= 23)
{
info->remainder = count - 16;
@ -3834,8 +3863,7 @@ get_shift_alg (enum shift_type shift_type, enum shift_mode shift_mode,
goto end;
}
}
else if ((TARGET_H8300H && count >= 24 || count <= 27)
|| (TARGET_H8300S && count >= 24 && count <= 25))
else if (count >= 24 && count <= 27)
{
info->remainder = count - 24;
@ -3874,7 +3902,10 @@ get_shift_alg (enum shift_type shift_type, enum shift_mode shift_mode,
info->special = "sub.w\t%f0,%f0\n\trotl.l\t#2,%S0\n\trotl.l\t#2,%S0\n\textu.l\t%S0";
goto end;
case SHIFT_ASHIFTRT:
gcc_unreachable ();
info->remainder = count - 24;
info->special = "mov.w\t%e0,%f0\n\tmov.b\t%t0,%s0\n\texts.w\t%f0\n\texts.l\t%S0";
info->cc_special = OLD_CC_SET_ZNV;
goto end;
}
}
else if (count == 29)
@ -3900,7 +3931,10 @@ get_shift_alg (enum shift_type shift_type, enum shift_mode shift_mode,
}
goto end;
case SHIFT_ASHIFTRT:
gcc_unreachable ();
info->remainder = count - 24;
info->special = "mov.w\t%e0,%f0\n\tmov.b\t%t0,%s0\n\texts.w\t%f0\n\texts.l\t%S0";
info->cc_special = OLD_CC_SET_ZNV;
goto end;
}
}
else if (count == 30)
@ -3920,7 +3954,10 @@ get_shift_alg (enum shift_type shift_type, enum shift_mode shift_mode,
info->special = "sub.w\t%f0,%f0\n\trotl.l\t#2,%S0\n\textu.l\t%S0";
goto end;
case SHIFT_ASHIFTRT:
gcc_unreachable ();
info->remainder = count - 24;
info->special = "mov.w\t%e0,%f0\n\tmov.b\t%t0,%s0\n\texts.w\t%f0\n\texts.l\t%S0";
info->cc_special = OLD_CC_SET_ZNV;
goto end;
}
}
else if (count == 31)