2016-05-20 12:26 GMT+03:00 Richard Biener <richard.guent...@gmail.com>:
> On Thu, May 19, 2016 at 9:36 PM, Ilya Enkovich <enkovich....@gmail.com> wrote:
>> Hi,
>>
>> This patch introduces new options used for loop epilogues vectorization.
>
> Why's that? This is a bit too much for the casual user and if it is
> really necessary
> to control this via options then it is not fine-grained enough.
>
> Why doesn't the vectorizer/backend have enough info to decide this itself?
I don't expect casual user to decide which modes to choose. These controls are
added for debugging and performance measurement purposes. I see now I miss
-ftree-vectorize-epilogues aliased to -ftree-vectorize-epilogues=all. Surely
I expect epilogues and short loops vectorization be enabled by default on -O3
or by -ftree-vectorize-loops.
Thanks,
Ilya
>
> Richard.
>
>> Thanks,
>> Ilya
>> --
>> gcc/
>>
>> 2016-05-19 Ilya Enkovich <ilya.enkov...@intel.com>
>>
>> * common.opt (flag_tree_vectorize_epilogues): New.
>> (ftree-vectorize-short-loops): New.
>> (ftree-vectorize-epilogues=): New.
>> (fno-tree-vectorize-epilogues): New.
>> (fvect-epilogue-cost-model=): New.
>> * flag-types.h (enum vect_epilogue_mode): New.
>> * opts.c (parse_vectorizer_options): New.
>> (common_handle_option): Support -ftree-vectorize-epilogues=
>> and -fno-tree-vectorize-epilogues options.
>>
>>
>> diff --git a/gcc/common.opt b/gcc/common.opt
>> index 682cb41..6b83b79 100644
>> --- a/gcc/common.opt
>> +++ b/gcc/common.opt
>> @@ -243,6 +243,10 @@ bool dump_base_name_prefixed = false
>> Variable
>> bool flag_disable_hsa = false
>>
>> +; Flag holding modes for loop epilogue vectorization
>> +Variable
>> +unsigned int flag_tree_vectorize_epilogues
>> +
>> ###
>> Driver
>>
>> @@ -2557,6 +2561,19 @@ ftree-vectorize
>> Common Report Var(flag_tree_vectorize) Optimization
>> Enable vectorization on trees.
>>
>> +ftree-vectorize-short-loops
>> +Common Report Var(flag_tree_vectorize_short_loops) Optimization
>> +Enable vectorization of loops with low trip count using masking.
>> +
>> +ftree-vectorize-epilogues=
>> +Common Report Joined Optimization
>> +Comma separated list of loop epilogue vectorization modes.
>> +Available modes: combine, mask, nomask.
>> +
>> +fno-tree-vectorize-epilogues
>> +Common RejectNegative Optimization
>> +Disable epilogues vectorization.
>> +
>> ftree-vectorizer-verbose=
>> Common Joined RejectNegative Ignore
>> Does nothing. Preserved for backward compatibility.
>> @@ -2577,6 +2594,10 @@ fsimd-cost-model=
>> Common Joined RejectNegative Enum(vect_cost_model)
>> Var(flag_simd_cost_model) Init(VECT_COST_MODEL_UNLIMITED) Optimization
>> Specifies the vectorization cost model for code marked with a simd
>> directive.
>>
>> +fvect-epilogue-cost-model=
>> +Common Joined RejectNegative Enum(vect_cost_model)
>> Var(flag_vect_epilogue_cost_model) Init(VECT_COST_MODEL_DEFAULT) Optimization
>> +Specifies the cost model for epilogue vectorization.
>> +
>> Enum
>> Name(vect_cost_model) Type(enum vect_cost_model) UnknownError(unknown
>> vectorizer cost model %qs)
>>
>> diff --git a/gcc/flag-types.h b/gcc/flag-types.h
>> index dd57e16..24081b1 100644
>> --- a/gcc/flag-types.h
>> +++ b/gcc/flag-types.h
>> @@ -200,6 +200,15 @@ enum vect_cost_model {
>> VECT_COST_MODEL_DEFAULT = 3
>> };
>>
>> +/* Epilogue vectorization modes. */
>> +enum vect_epilogue_mode {
>> + VECT_EPILOGUE_COMBINE = 1 << 0,
>> + VECT_EPILOGUE_MASK = 1 << 1,
>> + VECT_EPILOGUE_NOMASK = 1 << 2,
>> + VECT_EPILOGUE_ALL = VECT_EPILOGUE_COMBINE | VECT_EPILOGUE_MASK
>> + | VECT_EPILOGUE_NOMASK
>> +};
>> +
>> /* Different instrumentation modes. */
>> enum sanitize_code {
>> /* AddressSanitizer. */
>> diff --git a/gcc/opts.c b/gcc/opts.c
>> index 0f9431a..a0c0987 100644
>> --- a/gcc/opts.c
>> +++ b/gcc/opts.c
>> @@ -1531,6 +1531,63 @@ parse_sanitizer_options (const char *p, location_t
>> loc, int scode,
>> return flags;
>> }
>>
>> +/* Parse comma separated vectorizer suboptions from P for option SCODE,
>> + adjust previous FLAGS and return new ones. If COMPLAIN is false,
>> + don't issue diagnostics. */
>> +
>> +unsigned int
>> +parse_vectorizer_options (const char *p, location_t loc, int scode,
>> + unsigned int flags, int value, bool complain)
>> +{
>> + if (scode != OPT_ftree_vectorize_epilogues_)
>> + return flags;
>> +
>> + if (!p)
>> + return value;
>> +
>> + while (*p != 0)
>> + {
>> + size_t len;
>> + const char *comma = strchr (p, ',');
>> + unsigned int flag = 0;
>> +
>> + if (comma == NULL)
>> + len = strlen (p);
>> + else
>> + len = comma - p;
>> + if (len == 0)
>> + {
>> + p = comma + 1;
>> + continue;
>> + }
>> +
>> + /* Check to see if the string matches an option class name. */
>> + if (len == strlen ("combine")
>> + && memcmp (p, "combine", len) == 0)
>> + flag = VECT_EPILOGUE_COMBINE;
>> + else if (len == strlen ("mask")
>> + && memcmp (p, "mask", len) == 0)
>> + flag = VECT_EPILOGUE_MASK;
>> + else if (len == strlen ("nomask")
>> + && memcmp (p, "nomask", len) == 0)
>> + flag = VECT_EPILOGUE_NOMASK;
>> + else if (complain)
>> + error_at (loc, "unrecognized argument to -ftree-vectorize-epilogues=
>> "
>> + "option: %q.*s", (int) len, p);
>> +
>> + if (value)
>> + flags |= flag;
>> + else
>> + flags &= ~flag;
>> +
>> + if (comma == NULL)
>> + break;
>> + p = comma + 1;
>> + }
>> +
>> + return flags;
>> +}
>> +
>> /* Handle target- and language-independent options. Return zero to
>> generate an "unknown option" message. Only options that need
>> extra handling need to be listed here; if you simply want
>> @@ -2018,6 +2075,18 @@ common_handle_option (struct gcc_options *opts,
>> if (!opts_set->x_flag_tree_slp_vectorize)
>> opts->x_flag_tree_slp_vectorize = value;
>> break;
>> +
>> + case OPT_ftree_vectorize_epilogues_:
>> + opts->x_flag_tree_vectorize_epilogues
>> + = parse_vectorizer_options (arg, loc, code,
>> + opts->x_flag_tree_vectorize_epilogues,
>> + value, true);
>> + break;
>> +
>> + case OPT_fno_tree_vectorize_epilogues:
>> + opts->x_flag_tree_vectorize_epilogues = 0;
>> + break;
>> +
>> case OPT_fshow_column:
>> dc->show_column = value;
>> break;
