static int flush_reg_cond_reg_1 PARAMS ((splay_tree_node, void *));
static void flush_reg_cond_reg PARAMS ((struct propagate_block_info *,
int));
-static rtx ior_reg_cond PARAMS ((rtx, rtx));
+static rtx elim_reg_cond PARAMS ((rtx, unsigned int));
+static rtx ior_reg_cond PARAMS ((rtx, rtx, int));
static rtx not_reg_cond PARAMS ((rtx));
-static rtx nand_reg_cond PARAMS ((rtx, rtx));
+static rtx and_reg_cond PARAMS ((rtx, rtx, int));
#endif
#ifdef AUTO_INC_DEC
static void attempt_auto_inc PARAMS ((struct propagate_block_info *,
/* If this block ends in a conditional branch, for each register live
from one side of the branch and not the other, record the register
as conditionally dead. */
- if ((flags & (PROP_DEATH_NOTES | PROP_SCAN_DEAD_CODE))
- && GET_CODE (bb->end) == JUMP_INSN
+ if (GET_CODE (bb->end) == JUMP_INSN
&& any_condjump_p (bb->end))
{
regset_head diff_head;
cond = cond_false;
else
cond = cond_true;
- rcli->condition = alloc_EXPR_LIST (0, cond, NULL_RTX);
+ rcli->condition = cond;
splay_tree_insert (pbi->reg_cond_dead, i,
(splay_tree_value) rcli);
Record the current condition as the condition under
which it is dead. */
rcli = (struct reg_cond_life_info *) xmalloc (sizeof (*rcli));
- rcli->condition = alloc_EXPR_LIST (0, cond, NULL_RTX);
+ rcli->condition = cond;
splay_tree_insert (pbi->reg_cond_dead, regno,
(splay_tree_value) rcli);
Add the new condition to the old. */
rcli = (struct reg_cond_life_info *) node->value;
ncond = rcli->condition;
- ncond = ior_reg_cond (ncond, cond);
+ ncond = ior_reg_cond (ncond, cond, 1);
/* If the register is now unconditionally dead,
remove the entry in the splay_tree. */
splay_tree_value value;
{
struct reg_cond_life_info *rcli = (struct reg_cond_life_info *) value;
- free_EXPR_LIST_list (&rcli->condition);
free (rcli);
}
struct reg_cond_life_info *rcli;
int *xdata = (int *) data;
unsigned int regno = xdata[0];
- rtx c, *prev;
/* Don't need to search if last flushed value was farther on in
the in-order traversal. */
if (xdata[1] >= (int) node->key)
return 0;
-
+
/* Splice out portions of the expression that refer to regno. */
rcli = (struct reg_cond_life_info *) node->value;
- c = *(prev = &rcli->condition);
- while (c)
- {
- if (regno == REGNO (XEXP (XEXP (c, 0), 0)))
- {
- rtx next = XEXP (c, 1);
- free_EXPR_LIST_node (c);
- c = *prev = next;
- }
- else
- c = *(prev = &XEXP (c, 1));
- }
+ rcli->condition = elim_reg_cond (rcli->condition, regno);
- /* If the entire condition is now NULL, signal the node to be removed. */
- if (! rcli->condition)
+ /* If the entire condition is now false, signal the node to be removed. */
+ if (rcli->condition == const0_rtx)
{
xdata[1] = node->key;
return -1;
}
- else
- return 0;
+ else if (rcli->condition == const1_rtx)
+ abort ();
+
+ return 0;
}
/* Flush all (sub) expressions referring to REGNO from REG_COND_LIVE. */
CLEAR_REGNO_REG_SET (pbi->reg_cond_reg, regno);
}
-/* Logical arithmetic on predicate conditions. IOR, NOT and NAND.
- We actually use EXPR_LIST to chain the sub-expressions together
- instead of IOR because it's easier to manipulate and we have
- the lists.c functions to reuse nodes.
-
- Return a new rtl expression as appropriate. */
+/* Logical arithmetic on predicate conditions. IOR, NOT and AND.
+ For ior/and, the ADD flag determines whether we want to add the new
+ condition X to the old one unconditionally. If it is zero, we will
+ only return a new expression if X allows us to simplify part of
+ OLD, otherwise we return OLD unchanged to the caller.
+ If ADD is nonzero, we will return a new condition in all cases. The
+ toplevel caller of one of these functions should always pass 1 for
+ ADD. */
static rtx
-ior_reg_cond (old, x)
+ior_reg_cond (old, x, add)
rtx old, x;
+ int add;
{
- enum rtx_code x_code;
- rtx x_reg;
- rtx c;
-
- /* We expect these conditions to be of the form (eq reg 0). */
- x_code = GET_CODE (x);
- if (GET_RTX_CLASS (x_code) != '<'
- || GET_CODE (x_reg = XEXP (x, 0)) != REG
- || XEXP (x, 1) != const0_rtx)
- abort ();
+ rtx op0, op1;
- /* Search the expression for an existing sub-expression of X_REG. */
- for (c = old; c; c = XEXP (c, 1))
+ switch (GET_CODE (old))
{
- rtx y = XEXP (c, 0);
- if (REGNO (XEXP (y, 0)) == REGNO (x_reg))
+ case IOR:
+ op0 = ior_reg_cond (XEXP (old, 0), x, 0);
+ op1 = ior_reg_cond (XEXP (old, 1), x, 0);
+ if (op0 != XEXP (old, 0) || op1 != XEXP (old, 1))
{
- /* If we find X already present in OLD, we need do nothing. */
- if (GET_CODE (y) == x_code)
- return old;
-
- /* If we find X being a compliment of a condition in OLD,
- then the entire condition is true. */
- if (GET_CODE (y) == reverse_condition (x_code))
+ if (op0 == const0_rtx)
+ return op1;
+ if (op1 == const0_rtx)
+ return op0;
+ if (op0 == const1_rtx || op1 == const1_rtx)
return const1_rtx;
+ if (op0 == XEXP (old, 0))
+ op0 = gen_rtx_IOR (0, op0, x);
+ else
+ op1 = gen_rtx_IOR (0, op1, x);
+ return gen_rtx_IOR (0, op0, op1);
}
- }
+ if (! add)
+ return old;
+ return gen_rtx_IOR (0, old, x);
+
+ case AND:
+ op0 = ior_reg_cond (XEXP (old, 0), x, 0);
+ op1 = ior_reg_cond (XEXP (old, 1), x, 0);
+ if (op0 != XEXP (old, 0) || op1 != XEXP (old, 1))
+ {
+ if (op0 == const1_rtx)
+ return op1;
+ if (op1 == const1_rtx)
+ return op0;
+ if (op0 == const0_rtx || op1 == const0_rtx)
+ return const0_rtx;
+ if (op0 == XEXP (old, 0))
+ op0 = gen_rtx_IOR (0, op0, x);
+ else
+ op1 = gen_rtx_IOR (0, op1, x);
+ return gen_rtx_AND (0, op0, op1);
+ }
+ if (! add)
+ return old;
+ return gen_rtx_IOR (0, old, x);
+
+ case NOT:
+ op0 = and_reg_cond (XEXP (old, 0), not_reg_cond (x), 0);
+ if (op0 != XEXP (old, 0))
+ return not_reg_cond (op0);
+ if (! add)
+ return old;
+ return gen_rtx_IOR (0, old, x);
+
+ case EQ:
+ case NE:
+ if ((GET_CODE (x) == EQ || GET_CODE (x) == NE)
+ && GET_CODE (x) != GET_CODE (old)
+ && REGNO (XEXP (x, 0)) == REGNO (XEXP (old, 0)))
+ return const1_rtx;
+ if (GET_CODE (x) == GET_CODE (old)
+ && REGNO (XEXP (x, 0)) == REGNO (XEXP (old, 0)))
+ return old;
+ if (! add)
+ return old;
+ return gen_rtx_IOR (0, old, x);
- /* Otherwise just add to the chain. */
- return alloc_EXPR_LIST (0, x, old);
+ default:
+ abort ();
+ }
}
static rtx
rtx x;
{
enum rtx_code x_code;
- rtx x_reg;
- /* We expect these conditions to be of the form (eq reg 0). */
+ if (x == const0_rtx)
+ return const1_rtx;
+ else if (x == const1_rtx)
+ return const0_rtx;
x_code = GET_CODE (x);
- if (GET_RTX_CLASS (x_code) != '<'
- || GET_CODE (x_reg = XEXP (x, 0)) != REG
- || XEXP (x, 1) != const0_rtx)
- abort ();
+ if (x_code == NOT)
+ return XEXP (x, 0);
+ if (GET_RTX_CLASS (x_code) == '<'
+ && GET_CODE (XEXP (x, 0)) == REG)
+ {
+ if (XEXP (x, 1) != const0_rtx)
+ abort ();
- return alloc_EXPR_LIST (0, gen_rtx_fmt_ee (reverse_condition (x_code),
- VOIDmode, x_reg, const0_rtx),
- NULL_RTX);
+ return gen_rtx_fmt_ee (reverse_condition (x_code),
+ VOIDmode, XEXP (x, 0), const0_rtx);
+ }
+ return gen_rtx_NOT (0, x);
}
static rtx
-nand_reg_cond (old, x)
+and_reg_cond (old, x, add)
rtx old, x;
+ int add;
{
- enum rtx_code x_code;
- rtx x_reg;
- rtx c, *prev;
-
- /* We expect these conditions to be of the form (eq reg 0). */
- x_code = GET_CODE (x);
- if (GET_RTX_CLASS (x_code) != '<'
- || GET_CODE (x_reg = XEXP (x, 0)) != REG
- || XEXP (x, 1) != const0_rtx)
- abort ();
+ rtx op0, op1;
- /* Search the expression for an existing sub-expression of X_REG. */
-
- for (c = *(prev = &old); c; c = *(prev = &XEXP (c, 1)))
+ switch (GET_CODE (old))
{
- rtx y = XEXP (c, 0);
- if (REGNO (XEXP (y, 0)) == REGNO (x_reg))
+ case IOR:
+ op0 = and_reg_cond (XEXP (old, 0), x, 0);
+ op1 = and_reg_cond (XEXP (old, 1), x, 0);
+ if (op0 != XEXP (old, 0) || op1 != XEXP (old, 1))
{
- /* If we find X already present in OLD, then we need to
- splice it out. */
- if (GET_CODE (y) == x_code)
- {
- *prev = XEXP (c, 1);
- free_EXPR_LIST_node (c);
- return old ? old : const0_rtx;
- }
-
- /* If we find X being a compliment of a condition in OLD,
- then we need do nothing. */
- if (GET_CODE (y) == reverse_condition (x_code))
- return old;
+ if (op0 == const0_rtx)
+ return op1;
+ if (op1 == const0_rtx)
+ return op0;
+ if (op0 == const1_rtx || op1 == const1_rtx)
+ return const1_rtx;
+ if (op0 == XEXP (old, 0))
+ op0 = gen_rtx_AND (0, op0, x);
+ else
+ op1 = gen_rtx_AND (0, op1, x);
+ return gen_rtx_IOR (0, op0, op1);
}
+ if (! add)
+ return old;
+ return gen_rtx_AND (0, old, x);
+
+ case AND:
+ op0 = and_reg_cond (XEXP (old, 0), x, 0);
+ op1 = and_reg_cond (XEXP (old, 1), x, 0);
+ if (op0 != XEXP (old, 0) || op1 != XEXP (old, 1))
+ {
+ if (op0 == const1_rtx)
+ return op1;
+ if (op1 == const1_rtx)
+ return op0;
+ if (op0 == const0_rtx || op1 == const0_rtx)
+ return const0_rtx;
+ if (op0 == XEXP (old, 0))
+ op0 = gen_rtx_AND (0, op0, x);
+ else
+ op1 = gen_rtx_AND (0, op1, x);
+ return gen_rtx_AND (0, op0, op1);
+ }
+ if (! add)
+ return old;
+ return gen_rtx_AND (0, old, x);
+
+ case NOT:
+ op0 = ior_reg_cond (XEXP (old, 0), not_reg_cond (x), 0);
+ if (op0 != XEXP (old, 0))
+ return not_reg_cond (op0);
+ if (! add)
+ return old;
+ return gen_rtx_AND (0, old, x);
+
+ case EQ:
+ case NE:
+ if ((GET_CODE (x) == EQ || GET_CODE (x) == NE)
+ && GET_CODE (x) != GET_CODE (old)
+ && REGNO (XEXP (x, 0)) == REGNO (XEXP (old, 0)))
+ return const0_rtx;
+ if (GET_CODE (x) == GET_CODE (old)
+ && REGNO (XEXP (x, 0)) == REGNO (XEXP (old, 0)))
+ return old;
+ if (! add)
+ return old;
+ return gen_rtx_AND (0, old, x);
+
+ default:
+ abort ();
}
+}
+
+/* Given a condition X, remove references to reg REGNO and return the
+ new condition. The removal will be done so that all conditions
+ involving REGNO are considered to evaluate to false. This function
+ is used when the value of REGNO changes. */
- /* Otherwise, by implication, the register in question is now live for
- the inverse of the condition X. */
- return alloc_EXPR_LIST (0, gen_rtx_fmt_ee (reverse_condition (x_code),
- VOIDmode, x_reg, const0_rtx),
- old);
+static rtx
+elim_reg_cond (x, regno)
+ rtx x;
+ unsigned int regno;
+{
+ rtx op0, op1;
+ switch (GET_CODE (x))
+ {
+ case AND:
+ op0 = elim_reg_cond (XEXP (x, 0), regno);
+ op1 = elim_reg_cond (XEXP (x, 1), regno);
+ if (op0 == const0_rtx || op1 == const0_rtx)
+ return const0_rtx;
+ if (op0 == const1_rtx)
+ return op1;
+ if (op1 == const1_rtx)
+ return op0;
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
+ return x;
+ return gen_rtx_AND (0, op0, op1);
+
+ case IOR:
+ op0 = elim_reg_cond (XEXP (x, 0), regno);
+ op1 = elim_reg_cond (XEXP (x, 1), regno);
+ if (op0 == const1_rtx || op1 == const1_rtx)
+ return const1_rtx;
+ if (op0 == const0_rtx)
+ return op1;
+ if (op1 == const0_rtx)
+ return op0;
+ if (op0 == XEXP (x, 0) && op1 == XEXP (x, 1))
+ return x;
+ return gen_rtx_IOR (0, op0, op1);
+
+ case NOT:
+ op0 = elim_reg_cond (XEXP (x, 0), regno);
+ if (op0 == const0_rtx)
+ return const1_rtx;
+ if (op0 == const1_rtx)
+ return const0_rtx;
+ if (op0 != XEXP (x, 0))
+ return not_reg_cond (op0);
+ return x;
+
+ case EQ:
+ case NE:
+ if (REGNO (XEXP (x, 0)) == regno)
+ return const0_rtx;
+ return x;
+ default:
+ abort ();
+ }
}
#endif /* HAVE_conditional_execution */
\f
Subtract the new life cond from the old death cond. */
rcli = (struct reg_cond_life_info *) node->value;
ncond = rcli->condition;
- ncond = nand_reg_cond (ncond, cond);
+ ncond = and_reg_cond (ncond, not_reg_cond (cond), 1);
/* If the register is now unconditionally live, remove the
entry in the splay_tree. */
projects / gcc.git / commitdiff