On 07/14/11 18:29, Richard Henderson wrote:
> On 07/14/2011 09:23 AM, Bernd Schmidt wrote:
>> Ok, with gen_const_mem hacked into gcc-3.3 (minus setting MEM_READONLY_P
>> which doesn't exist in that tree) the load stays behind the branch where
>> it should be.
>>
>
> RTX_UNCHANGING_P was the bit back then, I believe.
Still ok with that also set:
addl r14 = @ltoff(ap_standalone#), r1
;;
.mii
ld8 r15 = [r14]
addl r14 = @ltoff(.LC2), r1
;;
(p7) addl r14 = 1, r0
;;
.mib
(p7) st4 [r15] = r14
nop.i 0
(p7) br.cond.dptk .L5
.mib
ld8 r14 = [r14]
And not ok if the MEM isn't exposed in RTL:
addl r14 = @ltoff(ap_standalone#), r1
;;
.mii
ld8 r15 = [r14]
addl r14 = @ltoff(.LC2), r1
;;
(p7) addl r14 = 1, r0
;;
.mii
(p7) st4 [r15] = r14
nop.i 0
nop.i 0
.mbb
ld8 r14 = [r14]
(p7) br.cond.dptk .L5
I'm attaching the 3.3 patch.
Bernd
Index: ../../branches/gcc-3_3-branch/gcc/sched-ebb.c
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/sched-ebb.c (revision 175226)
+++ ../../branches/gcc-3_3-branch/gcc/sched-ebb.c (working copy)
@@ -52,8 +52,7 @@ static int schedule_more_p PARAMS ((void
static const char *ebb_print_insn PARAMS ((rtx, int));
static int rank PARAMS ((rtx, rtx));
static int contributes_to_priority PARAMS ((rtx, rtx));
-static void compute_jump_reg_dependencies PARAMS ((rtx, regset, regset,
- regset));
+static void compute_jump_reg_dependencies PARAMS ((rtx, regset));
static void schedule_ebb PARAMS ((rtx, rtx));
/* Return nonzero if there are more insns that should be scheduled. */
@@ -161,30 +160,22 @@ contributes_to_priority (next, insn)
return 1;
}
-/* INSN is a JUMP_INSN, COND_SET is the set of registers that are
- conditionally set before INSN. Store the set of registers that
- must be considered as used by this jump in USED and that of
- registers that must be considered as set in SET. */
+/* INSN is a JUMP_INSN. Store the set of registers that must be considered
+ to be set by this jump in SET. */
static void
-compute_jump_reg_dependencies (insn, cond_set, used, set)
+compute_jump_reg_dependencies (insn, set)
rtx insn;
- regset cond_set, used, set;
+ regset set;
{
basic_block b = BLOCK_FOR_INSN (insn);
edge e;
for (e = b->succ; e; e = e->succ_next)
- if (e->flags & EDGE_FALLTHRU)
- /* The jump may be a by-product of a branch that has been merged
- in the main codepath after being conditionalized. Therefore
- it may guard the fallthrough block from using a value that has
- conditionally overwritten that of the main codepath. So we
- consider that it restores the value of the main codepath. */
- bitmap_operation (set, e->dest->global_live_at_start, cond_set,
- BITMAP_AND);
- else
- bitmap_operation (used, used, e->dest->global_live_at_start,
- BITMAP_IOR);
+ if ((e->flags & EDGE_FALLTHRU) == 0)
+ {
+ bitmap_operation (set, set, e->dest->global_live_at_start,
+ BITMAP_IOR);
+ }
}
/* Used in schedule_insns to initialize current_sched_info for scheduling
Index: ../../branches/gcc-3_3-branch/gcc/emit-rtl.c
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/emit-rtl.c (revision 175226)
+++ ../../branches/gcc-3_3-branch/gcc/emit-rtl.c (working copy)
@@ -192,6 +192,18 @@ static tree component_ref_for_mem_expr P
static rtx gen_const_vector_0 PARAMS ((enum machine_mode));
static void copy_rtx_if_shared_1 PARAMS ((rtx *orig));
+/* Generate a memory referring to non-trapping constant memory. */
+
+rtx
+gen_const_mem (enum machine_mode mode, rtx addr)
+{
+ rtx mem = gen_rtx_MEM (mode, addr);
+ RTX_UNCHANGING_P (mem) = 1;
+ MEM_NOTRAP_P (mem) = 1;
+ return mem;
+}
+
+
/* Probability of the conditional branch currently proceeded by try_split.
Set to -1 otherwise. */
int split_branch_probability = -1;
Index: ../../branches/gcc-3_3-branch/gcc/sched-deps.c
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/sched-deps.c (revision 175226)
+++ ../../branches/gcc-3_3-branch/gcc/sched-deps.c (working copy)
@@ -981,17 +981,12 @@ sched_analyze_insn (deps, x, insn, loop_
else
{
rtx pending, pending_mem;
- regset_head tmp_uses, tmp_sets;
- INIT_REG_SET (&tmp_uses);
- INIT_REG_SET (&tmp_sets);
-
- (*current_sched_info->compute_jump_reg_dependencies)
- (insn, &deps->reg_conditional_sets, &tmp_uses, &tmp_sets);
- IOR_REG_SET (reg_pending_uses, &tmp_uses);
- IOR_REG_SET (reg_pending_sets, &tmp_sets);
+ regset_head tmp;
+ INIT_REG_SET (&tmp);
- CLEAR_REG_SET (&tmp_uses);
- CLEAR_REG_SET (&tmp_sets);
+ (*current_sched_info->compute_jump_reg_dependencies) (insn, &tmp);
+ IOR_REG_SET (reg_pending_uses, &tmp);
+ CLEAR_REG_SET (&tmp);
/* All memory writes and volatile reads must happen before the
jump. Non-volatile reads must happen before the jump iff
@@ -1088,7 +1083,6 @@ sched_analyze_insn (deps, x, insn, loop_
}
flush_pending_lists (deps, insn, true, true);
- CLEAR_REG_SET (&deps->reg_conditional_sets);
reg_pending_barrier = false;
}
else
@@ -1120,7 +1114,6 @@ sched_analyze_insn (deps, x, insn, loop_
add_dependence_list (insn, reg_last->clobbers, REG_DEP_OUTPUT);
add_dependence_list (insn, reg_last->uses, REG_DEP_ANTI);
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
- SET_REGNO_REG_SET (&deps->reg_conditional_sets, i);
});
}
else
@@ -1169,7 +1162,6 @@ sched_analyze_insn (deps, x, insn, loop_
reg_last->sets = alloc_INSN_LIST (insn, reg_last->sets);
reg_last->uses_length = 0;
reg_last->clobbers_length = 0;
- CLEAR_REGNO_REG_SET (&deps->reg_conditional_sets, i);
});
}
@@ -1496,7 +1488,6 @@ init_deps (deps)
deps->reg_last = (struct deps_reg *)
xcalloc (max_reg, sizeof (struct deps_reg));
INIT_REG_SET (&deps->reg_last_in_use);
- INIT_REG_SET (&deps->reg_conditional_sets);
deps->pending_read_insns = 0;
deps->pending_read_mems = 0;
@@ -1539,7 +1530,6 @@ free_deps (deps)
free_INSN_LIST_list (®_last->clobbers);
});
CLEAR_REG_SET (&deps->reg_last_in_use);
- CLEAR_REG_SET (&deps->reg_conditional_sets);
free (deps->reg_last);
}
Index: ../../branches/gcc-3_3-branch/gcc/sched-int.h
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/sched-int.h (revision 175226)
+++ ../../branches/gcc-3_3-branch/gcc/sched-int.h (working copy)
@@ -112,9 +112,6 @@ struct deps
/* Element N is set for each register that has any nonzero element
in reg_last[N].{uses,sets,clobbers}. */
regset_head reg_last_in_use;
-
- /* Element N is set for each register that is conditionally set. */
- regset_head reg_conditional_sets;
};
/* This structure holds some state of the current scheduling pass, and
@@ -149,9 +146,9 @@ struct sched_info
calculations. */
int (*contributes_to_priority) PARAMS ((rtx, rtx));
/* Called when computing dependencies for a JUMP_INSN. This function
- should store the set of registers that must be considered as used
- and the set of registers that must be considered as set by the jump. */
- void (*compute_jump_reg_dependencies) PARAMS ((rtx, regset, regset, regset));
+ should store the set of registers that must be considered as set by
+ the jump in the regset. */
+ void (*compute_jump_reg_dependencies) PARAMS ((rtx, regset));
/* The boundaries of the set of insns to be scheduled. */
rtx prev_head, next_tail;
Index: ../../branches/gcc-3_3-branch/gcc/sched-rgn.c
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/sched-rgn.c (revision 175226)
+++ ../../branches/gcc-3_3-branch/gcc/sched-rgn.c (working copy)
@@ -1968,8 +1968,7 @@ static int schedule_more_p PARAMS ((void
static const char *rgn_print_insn PARAMS ((rtx, int));
static int rgn_rank PARAMS ((rtx, rtx));
static int contributes_to_priority PARAMS ((rtx, rtx));
-static void compute_jump_reg_dependencies PARAMS ((rtx, regset, regset,
- regset));
+static void compute_jump_reg_dependencies PARAMS ((rtx, regset));
/* Return nonzero if there are more insns that should be scheduled. */
@@ -2256,16 +2255,12 @@ contributes_to_priority (next, insn)
return BLOCK_NUM (next) == BLOCK_NUM (insn);
}
-/* INSN is a JUMP_INSN, COND_SET is the set of registers that are
- conditionally set before INSN. Store the set of registers that
- must be considered as used by this jump in USED and that of
- registers that must be considered as set in SET. */
+/* INSN is a JUMP_INSN. Store the set of registers that must be considered
+ to be set by this jump in SET. */
static void
-compute_jump_reg_dependencies (insn, cond_set, used, set)
+compute_jump_reg_dependencies (insn, set)
rtx insn ATTRIBUTE_UNUSED;
- regset cond_set ATTRIBUTE_UNUSED;
- regset used ATTRIBUTE_UNUSED;
regset set ATTRIBUTE_UNUSED;
{
/* Nothing to do here, since we postprocess jumps in
Index: ../../branches/gcc-3_3-branch/gcc/config/ia64/ia64.md
===================================================================
--- ../../branches/gcc-3_3-branch/gcc/config/ia64/ia64.md (revision
175226)
+++ ../../branches/gcc-3_3-branch/gcc/config/ia64/ia64.md (working copy)
@@ -534,13 +534,19 @@ (define_expand "load_symptr"
(plus:DI (high:DI (match_operand:DI 1 "got_symbolic_operand" ""))
(match_dup 3)))
(set (match_operand:DI 0 "register_operand" "")
- (lo_sum:DI (match_dup 2) (match_dup 1)))]
+ (lo_sum:DI (mem:DI (match_dup 2)) (match_dup 1)))]
""
{
operands[3] = pic_offset_table_rtx;
+ emit_insn (gen_load_symptr_high (operands[2], operands[1], operands[3]));
+ emit_insn (gen_rtx_SET (VOIDmode, operands[0],
+ gen_rtx_LO_SUM (DImode, gen_const_mem (DImode,
+ operands[2]),
+ operands[1])));
+ DONE;
})
-(define_insn "*load_symptr_high"
+(define_insn "load_symptr_high"
[(set (match_operand:DI 0 "register_operand" "=r")
(plus:DI (high:DI (match_operand 1 "got_symbolic_operand" "s"))
(match_operand:DI 2 "register_operand" "a")))]
@@ -555,7 +561,7 @@ (define_insn "*load_symptr_high"
(define_insn "*load_symptr_low"
[(set (match_operand:DI 0 "register_operand" "=r")
- (lo_sum:DI (match_operand:DI 1 "register_operand" "r")
+ (lo_sum:DI (mem:DI (match_operand:DI 1 "register_operand" "r"))
(match_operand 2 "got_symbolic_operand" "s")))]
""
{
