[9/9] Simplify register bitmap operations
Richard Sandiford
richard.sandiford@arm.com
Mon May 18 18:31:00 GMT 2015
After the previous changes, several callers are left with code like:
if (HARD_REGISTER_P (x))
bitmap_foo_range (x, REGNO (x), REG_NREGS (x));
else
bitmap_foo (x, REGNO (x));
These might as well now be:
if (REG_NREGS (x) > 1)
bitmap_foo_range (x, REGNO (x), REG_NREGS (x));
else
bitmap_foo (x, REGNO (x));
since REG_NREGS is as cheap to test, and since single-register hard REGs
are the common case. But if separating out the cases is a win -- and it
seems to be, very slightly -- then it would be better to add the shortcut
to the range functions themselves.
gcc/
* bitmap.c (bitmap_set_range): Handle count==1 specially.
(bitmap_clear_range): Likewise.
* cfgcleanup.c (mark_effect): Use bitmap_clear_range and
bitmap_set_range unconditionally.
* df-problems.c (df_simulate_one_insn_forwards): Likewise.
* df-scan.c (df_mark_reg): Likewise.
* haifa-sched.c (setup_ref_regs): Likewise.
* sched-rgn.c (update_live_1): Likewise.
Index: gcc/bitmap.c
===================================================================
--- gcc/bitmap.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/bitmap.c 2015-05-18 08:38:25.841752865 +0100
@@ -1212,6 +1212,12 @@ bitmap_set_range (bitmap head, unsigned
if (!count)
return;
+ if (count == 1)
+ {
+ bitmap_set_bit (head, start);
+ return;
+ }
+
first_index = start / BITMAP_ELEMENT_ALL_BITS;
end_bit_plus1 = start + count;
last_index = (end_bit_plus1 - 1) / BITMAP_ELEMENT_ALL_BITS;
@@ -1311,6 +1317,12 @@ bitmap_clear_range (bitmap head, unsigne
if (!count)
return;
+ if (count == 1)
+ {
+ bitmap_clear_bit (head, start);
+ return;
+ }
+
first_index = start / BITMAP_ELEMENT_ALL_BITS;
end_bit_plus1 = start + count;
last_index = (end_bit_plus1 - 1) / BITMAP_ELEMENT_ALL_BITS;
Index: gcc/cfgcleanup.c
===================================================================
--- gcc/cfgcleanup.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/cfgcleanup.c 2015-05-18 08:38:25.841752865 +0100
@@ -222,22 +222,15 @@ try_simplify_condjump (basic_block cbran
static bool
mark_effect (rtx exp, regset nonequal)
{
- int regno;
rtx dest;
switch (GET_CODE (exp))
{
/* In case we do clobber the register, mark it as equal, as we know the
value is dead so it don't have to match. */
case CLOBBER:
- if (REG_P (XEXP (exp, 0)))
- {
- dest = XEXP (exp, 0);
- regno = REGNO (dest);
- if (HARD_REGISTER_NUM_P (regno))
- bitmap_clear_range (nonequal, regno, REG_NREGS (dest));
- else
- bitmap_clear_bit (nonequal, regno);
- }
+ dest = XEXP (exp, 0);
+ if (REG_P (dest))
+ bitmap_clear_range (nonequal, REGNO (dest), REG_NREGS (dest));
return false;
case SET:
@@ -248,11 +241,7 @@ mark_effect (rtx exp, regset nonequal)
return false;
if (!REG_P (dest))
return true;
- regno = REGNO (dest);
- if (HARD_REGISTER_NUM_P (regno))
- bitmap_set_range (nonequal, regno, REG_NREGS (dest));
- else
- bitmap_set_bit (nonequal, regno);
+ bitmap_set_range (nonequal, REGNO (dest), REG_NREGS (dest));
return false;
default:
Index: gcc/df-problems.c
===================================================================
--- gcc/df-problems.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/df-problems.c 2015-05-18 08:38:25.845752816 +0100
@@ -3574,11 +3574,7 @@ df_simulate_one_insn_forwards (basic_blo
case REG_UNUSED:
{
rtx reg = XEXP (link, 0);
- int regno = REGNO (reg);
- if (HARD_REGISTER_NUM_P (regno))
- bitmap_clear_range (live, regno, REG_NREGS (reg));
- else
- bitmap_clear_bit (live, regno);
+ bitmap_clear_range (live, REGNO (reg), REG_NREGS (reg));
}
break;
default:
Index: gcc/df-scan.c
===================================================================
--- gcc/df-scan.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/df-scan.c 2015-05-18 08:38:25.841752865 +0100
@@ -3518,15 +3518,7 @@ df_get_eh_block_artificial_uses (bitmap
static void
df_mark_reg (rtx reg, void *vset)
{
- bitmap set = (bitmap) vset;
- int regno = REGNO (reg);
-
- gcc_assert (GET_MODE (reg) != BLKmode);
-
- if (regno < FIRST_PSEUDO_REGISTER)
- bitmap_set_range (set, regno, REG_NREGS (reg));
- else
- bitmap_set_bit (set, regno);
+ bitmap_set_range ((bitmap) vset, REGNO (reg), REG_NREGS (reg));
}
Index: gcc/haifa-sched.c
===================================================================
--- gcc/haifa-sched.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/haifa-sched.c 2015-05-18 08:38:25.845752816 +0100
@@ -1032,17 +1032,13 @@ initiate_reg_pressure_info (bitmap live)
static void
setup_ref_regs (rtx x)
{
- int i, j, regno;
+ int i, j;
const RTX_CODE code = GET_CODE (x);
const char *fmt;
if (REG_P (x))
{
- regno = REGNO (x);
- if (HARD_REGISTER_NUM_P (regno))
- bitmap_set_range (region_ref_regs, regno, REG_NREGS (x));
- else
- bitmap_set_bit (region_ref_regs, REGNO (x));
+ bitmap_set_range (region_ref_regs, REGNO (x), REG_NREGS (x));
return;
}
fmt = GET_RTX_FORMAT (code);
Index: gcc/sched-rgn.c
===================================================================
--- gcc/sched-rgn.c 2015-05-18 08:38:25.845752816 +0100
+++ gcc/sched-rgn.c 2015-05-18 08:38:25.845752816 +0100
@@ -1801,11 +1801,7 @@ update_live_1 (int src, rtx x)
for (i = 0; i < candidate_table[src].update_bbs.nr_members; i++)
{
basic_block b = candidate_table[src].update_bbs.first_member[i];
-
- if (HARD_REGISTER_NUM_P (regno))
- bitmap_set_range (df_get_live_in (b), regno, REG_NREGS (reg));
- else
- bitmap_set_bit (df_get_live_in (b), regno);
+ bitmap_set_range (df_get_live_in (b), regno, REG_NREGS (reg));
}
}
}
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