Hi Richard,
Thanks for the comments!
on 2020/6/29 下午6:07, Richard Sandiford wrote:
> Thanks for the update. I agree with the summary of the IRC discussion
> except for…
>
> "Kewen.Lin" <[email protected]> writes:
>> Hi Richard S./Richi/Jim/Segher,
>>
>> Thanks a lot for your comments to make this patch more solid.
>>
>> Based on our discussion, for the vector load/store with length
>> optab, the length unit would be measured in lanes by default.
>> For the targets which support length measured in bytes like Power,
>> they should only define VnQI modes to wrap the other same size
>> vector modes. If the length is larger than total lane/byte count
>> of the given mode, it's taken to load all lanes/bytes implicitly.
>
> …this last bit. IMO the behaviour of the optab should be undefined
> when the supplied length is greater than the number of lanes.
>
> I think that also makes things better for the lxvl implementation,
> which ignores the upper 56 bits of the length. It sounds like the
> above semantics would instead require Power to saturate the value
> at 255 before shifting it.
>
Good catch, I just realized that this part is inconsistent to what I
implemented in patch 5/7, where the function vect_gen_len still does
the min operation between the given length and length_limit.
This patch is updated accordingly to state the behavior to be undefined.
The others aren't required to change.
Could you have a further look? Thanks in advance!
v6/v7: Updated optab descriptions.
v5:
- Updated lenload/lenstore optab to len_load/len_store and the docs.
- Rename expand_mask_{load,store}_optab_fn to
expand_partial_{load,store}_optab_fn
- Added/updated macros for expand_mask_{load,store}_optab_fn
and expand_len_{load,store}_optab_fn
v4: Update len_load_direct/len_store_direct to align with direct optab.
v3: Get rid of length mode hook.
BR,
Kewen
-----
gcc/ChangeLog:
2020-MM-DD Kewen Lin <[email protected]>
* doc/md.texi (len_load_@var{m}): Document.
(len_store_@var{m}): Likewise.
* internal-fn.c (len_load_direct): New macro.
(len_store_direct): Likewise.
(expand_len_load_optab_fn): Likewise.
(expand_len_store_optab_fn): Likewise.
(direct_len_load_optab_supported_p): Likewise.
(direct_len_store_optab_supported_p): Likewise.
(expand_mask_load_optab_fn): New macro. Original renamed to ...
(expand_partial_load_optab_fn): ... here. Add handlings for
len_load_optab.
(expand_mask_store_optab_fn): New macro. Original renamed to ...
(expand_partial_store_optab_fn): ... here. Add handlings for
len_store_optab.
(internal_load_fn_p): Handle IFN_LEN_LOAD.
(internal_store_fn_p): Handle IFN_LEN_STORE.
(internal_fn_stored_value_index): Handle IFN_LEN_STORE.
* internal-fn.def (LEN_LOAD): New internal function.
(LEN_STORE): Likewise.
* optabs.def (len_load_optab, len_store_optab): New optab.
diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi
index 2c67c818da5..c8d7bcc7f62 100644
--- a/gcc/doc/md.texi
+++ b/gcc/doc/md.texi
@@ -5167,6 +5167,33 @@ mode @var{n}.
This pattern is not allowed to @code{FAIL}.
+@cindex @code{len_load_@var{m}} instruction pattern
+@item @samp{len_load_@var{m}}
+Load the number of units specified by operand 2 from memory operand 1
+into register operand 0, setting the other bytes of operand 0 to
+undefined values. Operands 0 and 1 have mode @var{m}. Operand 2 has
+whichever integer mode the target prefers. If operand 2 exceeds the
+maximum units of mode @var{m}, the behavior is undefined. For targets
+which support length measured in bytes, they should only define VnQI
+mode to wrap the other vector modes with the same size. Meanwhile,
+it's required that the byte count should be a multiple of the element
+size (wrapped vector).
+
+This pattern is not allowed to @code{FAIL}.
+
+@cindex @code{len_store_@var{m}} instruction pattern
+@item @samp{len_store_@var{m}}
+Store the number of units specified by operand 2 from nonmemory operand 1
+into memory operand 0, leaving the other bytes of operand 0 unchanged.
+Operands 0 and 1 have mode @var{m}. Operand 2 has whichever integer
+mode the target prefers. If operand 2 exceeds the maximum units of mode
+@var{m}, the behavior is undefined. For targets which support length
+measured in bytes, they should only define VnQI mode to wrap the other
+vector modes with the same size. Meanwhile, it's required that the byte
+count should be a multiple of the element size (wrapped vector).
+
+This pattern is not allowed to @code{FAIL}.
+
@cindex @code{vec_perm@var{m}} instruction pattern
@item @samp{vec_perm@var{m}}
Output a (variable) vector permutation. Operand 0 is the destination
diff --git a/gcc/internal-fn.c b/gcc/internal-fn.c
index 4f088de48d5..1e53ced60eb 100644
--- a/gcc/internal-fn.c
+++ b/gcc/internal-fn.c
@@ -104,10 +104,12 @@ init_internal_fns ()
#define load_lanes_direct { -1, -1, false }
#define mask_load_lanes_direct { -1, -1, false }
#define gather_load_direct { 3, 1, false }
+#define len_load_direct { -1, -1, false }
#define mask_store_direct { 3, 2, false }
#define store_lanes_direct { 0, 0, false }
#define mask_store_lanes_direct { 0, 0, false }
#define scatter_store_direct { 3, 1, false }
+#define len_store_direct { 3, 3, false }
#define unary_direct { 0, 0, true }
#define binary_direct { 0, 0, true }
#define ternary_direct { 0, 0, true }
@@ -2478,10 +2480,10 @@ expand_call_mem_ref (tree type, gcall *stmt, int index)
return fold_build2 (MEM_REF, type, addr, build_int_cst (alias_ptr_type, 0));
}
-/* Expand MASK_LOAD{,_LANES} call STMT using optab OPTAB. */
+/* Expand MASK_LOAD{,_LANES} or LEN_LOAD call STMT using optab OPTAB. */
static void
-expand_mask_load_optab_fn (internal_fn, gcall *stmt, convert_optab optab)
+expand_partial_load_optab_fn (internal_fn, gcall *stmt, convert_optab optab)
{
class expand_operand ops[3];
tree type, lhs, rhs, maskt;
@@ -2497,6 +2499,8 @@ expand_mask_load_optab_fn (internal_fn, gcall *stmt,
convert_optab optab)
if (optab == vec_mask_load_lanes_optab)
icode = get_multi_vector_move (type, optab);
+ else if (optab == len_load_optab)
+ icode = direct_optab_handler (optab, TYPE_MODE (type));
else
icode = convert_optab_handler (optab, TYPE_MODE (type),
TYPE_MODE (TREE_TYPE (maskt)));
@@ -2507,18 +2511,24 @@ expand_mask_load_optab_fn (internal_fn, gcall *stmt,
convert_optab optab)
target = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
create_output_operand (&ops[0], target, TYPE_MODE (type));
create_fixed_operand (&ops[1], mem);
- create_input_operand (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)));
+ if (optab == len_load_optab)
+ create_convert_operand_from (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)),
+ TYPE_UNSIGNED (TREE_TYPE (maskt)));
+ else
+ create_input_operand (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)));
expand_insn (icode, 3, ops);
if (!rtx_equal_p (target, ops[0].value))
emit_move_insn (target, ops[0].value);
}
+#define expand_mask_load_optab_fn expand_partial_load_optab_fn
#define expand_mask_load_lanes_optab_fn expand_mask_load_optab_fn
+#define expand_len_load_optab_fn expand_partial_load_optab_fn
-/* Expand MASK_STORE{,_LANES} call STMT using optab OPTAB. */
+/* Expand MASK_STORE{,_LANES} or LEN_STORE call STMT using optab OPTAB. */
static void
-expand_mask_store_optab_fn (internal_fn, gcall *stmt, convert_optab optab)
+expand_partial_store_optab_fn (internal_fn, gcall *stmt, convert_optab optab)
{
class expand_operand ops[3];
tree type, lhs, rhs, maskt;
@@ -2532,6 +2542,8 @@ expand_mask_store_optab_fn (internal_fn, gcall *stmt,
convert_optab optab)
if (optab == vec_mask_store_lanes_optab)
icode = get_multi_vector_move (type, optab);
+ else if (optab == len_store_optab)
+ icode = direct_optab_handler (optab, TYPE_MODE (type));
else
icode = convert_optab_handler (optab, TYPE_MODE (type),
TYPE_MODE (TREE_TYPE (maskt)));
@@ -2542,11 +2554,17 @@ expand_mask_store_optab_fn (internal_fn, gcall *stmt,
convert_optab optab)
reg = expand_normal (rhs);
create_fixed_operand (&ops[0], mem);
create_input_operand (&ops[1], reg, TYPE_MODE (type));
- create_input_operand (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)));
+ if (optab == len_store_optab)
+ create_convert_operand_from (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)),
+ TYPE_UNSIGNED (TREE_TYPE (maskt)));
+ else
+ create_input_operand (&ops[2], mask, TYPE_MODE (TREE_TYPE (maskt)));
expand_insn (icode, 3, ops);
}
+#define expand_mask_store_optab_fn expand_partial_store_optab_fn
#define expand_mask_store_lanes_optab_fn expand_mask_store_optab_fn
+#define expand_len_store_optab_fn expand_partial_store_optab_fn
static void
expand_ABNORMAL_DISPATCHER (internal_fn, gcall *)
@@ -3128,10 +3146,12 @@ multi_vector_optab_supported_p (convert_optab optab,
tree_pair types,
#define direct_load_lanes_optab_supported_p multi_vector_optab_supported_p
#define direct_mask_load_lanes_optab_supported_p multi_vector_optab_supported_p
#define direct_gather_load_optab_supported_p convert_optab_supported_p
+#define direct_len_load_optab_supported_p direct_optab_supported_p
#define direct_mask_store_optab_supported_p convert_optab_supported_p
#define direct_store_lanes_optab_supported_p multi_vector_optab_supported_p
#define direct_mask_store_lanes_optab_supported_p
multi_vector_optab_supported_p
#define direct_scatter_store_optab_supported_p convert_optab_supported_p
+#define direct_len_store_optab_supported_p direct_optab_supported_p
#define direct_while_optab_supported_p convert_optab_supported_p
#define direct_fold_extract_optab_supported_p direct_optab_supported_p
#define direct_fold_left_optab_supported_p direct_optab_supported_p
@@ -3498,6 +3518,7 @@ internal_load_fn_p (internal_fn fn)
case IFN_MASK_LOAD_LANES:
case IFN_GATHER_LOAD:
case IFN_MASK_GATHER_LOAD:
+ case IFN_LEN_LOAD:
return true;
default:
@@ -3517,6 +3538,7 @@ internal_store_fn_p (internal_fn fn)
case IFN_MASK_STORE_LANES:
case IFN_SCATTER_STORE:
case IFN_MASK_SCATTER_STORE:
+ case IFN_LEN_STORE:
return true;
default:
@@ -3577,6 +3599,7 @@ internal_fn_stored_value_index (internal_fn fn)
case IFN_MASK_STORE:
case IFN_SCATTER_STORE:
case IFN_MASK_SCATTER_STORE:
+ case IFN_LEN_STORE:
return 3;
default:
diff --git a/gcc/internal-fn.def b/gcc/internal-fn.def
index 1d190d492ff..17dac128e83 100644
--- a/gcc/internal-fn.def
+++ b/gcc/internal-fn.def
@@ -49,11 +49,13 @@ along with GCC; see the file COPYING3. If not see
- load_lanes: currently just vec_load_lanes
- mask_load_lanes: currently just vec_mask_load_lanes
- gather_load: used for {mask_,}gather_load
+ - len_load: currently just len_load
- mask_store: currently just maskstore
- store_lanes: currently just vec_store_lanes
- mask_store_lanes: currently just vec_mask_store_lanes
- scatter_store: used for {mask_,}scatter_store
+ - len_store: currently just len_store
- unary: a normal unary optab, such as vec_reverse_<mode>
- binary: a normal binary optab, such as vec_interleave_lo_<mode>
@@ -127,6 +129,8 @@ DEF_INTERNAL_OPTAB_FN (GATHER_LOAD, ECF_PURE, gather_load,
gather_load)
DEF_INTERNAL_OPTAB_FN (MASK_GATHER_LOAD, ECF_PURE,
mask_gather_load, gather_load)
+DEF_INTERNAL_OPTAB_FN (LEN_LOAD, ECF_PURE, len_load, len_load)
+
DEF_INTERNAL_OPTAB_FN (SCATTER_STORE, 0, scatter_store, scatter_store)
DEF_INTERNAL_OPTAB_FN (MASK_SCATTER_STORE, 0,
mask_scatter_store, scatter_store)
@@ -136,6 +140,8 @@ DEF_INTERNAL_OPTAB_FN (STORE_LANES, ECF_CONST,
vec_store_lanes, store_lanes)
DEF_INTERNAL_OPTAB_FN (MASK_STORE_LANES, 0,
vec_mask_store_lanes, mask_store_lanes)
+DEF_INTERNAL_OPTAB_FN (LEN_STORE, 0, len_store, len_store)
+
DEF_INTERNAL_OPTAB_FN (WHILE_ULT, ECF_CONST | ECF_NOTHROW, while_ult, while)
DEF_INTERNAL_OPTAB_FN (CHECK_RAW_PTRS, ECF_CONST | ECF_NOTHROW,
check_raw_ptrs, check_ptrs)
diff --git a/gcc/optabs.def b/gcc/optabs.def
index 0c64eb52a8d..78409aa1453 100644
--- a/gcc/optabs.def
+++ b/gcc/optabs.def
@@ -435,3 +435,5 @@ OPTAB_D (check_war_ptrs_optab, "check_war_ptrs$a")
OPTAB_DC (vec_duplicate_optab, "vec_duplicate$a", VEC_DUPLICATE)
OPTAB_DC (vec_series_optab, "vec_series$a", VEC_SERIES)
OPTAB_D (vec_shl_insert_optab, "vec_shl_insert_$a")
+OPTAB_D (len_load_optab, "len_load_$a")
+OPTAB_D (len_store_optab, "len_store_$a")
