This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH] Remove ix86_legitimate_combined_insn
- From: "H.J. Lu" <hjl dot tools at gmail dot com>
- To: Uros Bizjak <ubizjak at gmail dot com>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Tue, 19 Apr 2016 08:36:48 -0700
- Subject: Re: [PATCH] Remove ix86_legitimate_combined_insn
- Authentication-results: sourceware.org; auth=none
- References: <20160419144931 dot GB7801 at intel dot com> <CAFULd4b10NVsgdRq9j5VGcbYGY2VPgG7dU3sC8Qwtrx9+z1KPQ at mail dot gmail dot com> <CAMe9rOpEif5ZahcR9D916YGj_ZSMM02gQYqxNDPCjj_GHH3bwQ at mail dot gmail dot com> <CAFULd4ak_w4W0yq8ugdQOi6iw+DptLcagRj=TXTgjxeMzUspyg at mail dot gmail dot com>
On Tue, Apr 19, 2016 at 8:27 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
> On Tue, Apr 19, 2016 at 5:18 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
>> On Tue, Apr 19, 2016 at 8:08 AM, Uros Bizjak <ubizjak@gmail.com> wrote:
>>> On Tue, Apr 19, 2016 at 4:49 PM, H.J. Lu <hongjiu.lu@intel.com> wrote:
>>>>
>>>> From INSTRUCTION EXCEPTION SPECIFICATION section in Intel software
>>>> developer manual volume 2, only legacy SSE instructions with memory
>>>> operand not 16-byte aligned get General Protection fault. There is
>>>> no need to check 1, 2, 4, 8 byte alignments. Since x86 backend has
>>>> accurate constraints and predicates for 16-byte alignment, we can
>>>> remove ix86_legitimate_combined_insn.
>>>>
>>>> Tested on x86-64. OK for trunk?
>>>
>>> No. This function also handles cases where invalid hard register gets
>>> propagated into the insn during the combine pass, leading to spill
>>> failure later.
>>>
>>
>> ix86_legitimate_combined_insn was added to work around the
>> reload issue:
>
> Sorry, I'm not convinced. Please see [1].
>
> You should remove only this part, together with now unused ssememalign
> attribute.
>
> - /* For pre-AVX disallow unaligned loads/stores where the
> - instructions don't support it. */
> - if (!TARGET_AVX
> - && VECTOR_MODE_P (mode)
> - && misaligned_operand (op, mode))
> - {
> - unsigned int min_align = get_attr_ssememalign (insn);
> - if (min_align == 0
> - || MEM_ALIGN (op) < min_align)
> - return false;
> - }
>
>> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46829
>> https://gcc.gnu.org/bugzilla/show_bug.cgi?id=46843
>
>> LRA doesn't have those limitation. Removing
>> ix86_legitimate_combined_insn causes no regressions.
>
> [1] https://gcc.gnu.org/ml/gcc-patches/2012-08/msg01195.html
>
> Uros.
Here is the updated patch. OK for trunk if there is no regression
on x86-64?
--
H.J.
From d558242ecf4f9acd9ae4b0e1cda28fed6a75d99d Mon Sep 17 00:00:00 2001
From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Sat, 2 Jan 2016 14:57:09 -0800
Subject: [PATCH] Remove ssememalign
From INSTRUCTION EXCEPTION SPECIFICATION section in Intel software
developer manual volume 2, only legacy SSE instructions with memory
operand not 16-byte aligned get General Protection fault. There is
no need to check 1, 2, 4, 8 byte alignments. Since x86 backend has
accurate constraints and predicates for 16-byte alignment, we can
remove alignment check in ix86_legitimate_combined_insn.
* config/i386/i386.c (ix86_legitimate_combined_insn): Remove
alignment check.
* config/i386/i386.md (ssememalign): Removed.
* config/i386/sse.md: Remove ssememalign attribute from patterns.
---
gcc/config/i386/i386.c | 12 ------------
gcc/config/i386/i386.md | 7 -------
gcc/config/i386/sse.md | 30 ------------------------------
3 files changed, 49 deletions(-)
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index d6c9200..6379313 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -7317,18 +7317,6 @@ ix86_legitimate_combined_insn (rtx_insn *insn)
bool win;
int j;
- /* For pre-AVX disallow unaligned loads/stores where the
- instructions don't support it. */
- if (!TARGET_AVX
- && VECTOR_MODE_P (mode)
- && misaligned_operand (op, mode))
- {
- unsigned int min_align = get_attr_ssememalign (insn);
- if (min_align == 0
- || MEM_ALIGN (op) < min_align)
- return false;
- }
-
/* A unary operator may be accepted by the predicate, but it
is irrelevant for matching constraints. */
if (UNARY_P (op))
diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 6596a1d..38eb98c 100644
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -460,13 +460,6 @@
(const_string "unknown")]
(const_string "integer")))
-;; The minimum required alignment of vector mode memory operands of the SSE
-;; (non-VEX/EVEX) instruction in bits, if it is different from
-;; GET_MODE_ALIGNMENT of the operand, otherwise 0. If an instruction has
-;; multiple alternatives, this should be conservative maximum of those minimum
-;; required alignments.
-(define_attr "ssememalign" "" (const_int 0))
-
;; The (bounding maximum) length of an instruction immediate.
(define_attr "length_immediate" ""
(cond [(eq_attr "type" "incdec,setcc,icmov,str,lea,other,multi,idiv,leave,
diff --git a/gcc/config/i386/sse.md b/gcc/config/i386/sse.md
index ed0a1a6..78c28c5 100644
--- a/gcc/config/i386/sse.md
+++ b/gcc/config/i386/sse.md
@@ -1181,7 +1181,6 @@
"%vlddqu\t{%1, %0|%0, %1}"
[(set_attr "type" "ssemov")
(set_attr "movu" "1")
- (set_attr "ssememalign" "8")
(set (attr "prefix_data16")
(if_then_else
(match_test "TARGET_AVX")
@@ -1446,7 +1445,6 @@
vrcpss\t{%1, %2, %0|%0, %2, %k1}"
[(set_attr "isa" "noavx,avx")
(set_attr "type" "sse")
- (set_attr "ssememalign" "32")
(set_attr "atom_sse_attr" "rcp")
(set_attr "btver2_sse_attr" "rcp")
(set_attr "prefix" "orig,vex")
@@ -1588,7 +1586,6 @@
vrsqrtss\t{%1, %2, %0|%0, %2, %k1}"
[(set_attr "isa" "noavx,avx")
(set_attr "type" "sse")
- (set_attr "ssememalign" "32")
(set_attr "prefix" "orig,vex")
(set_attr "mode" "SF")])
@@ -4690,7 +4687,6 @@
"%vcvtdq2pd\t{%1, %0<mask_operand2>|%0<mask_operand2>, %q1}"
[(set_attr "type" "ssecvt")
(set_attr "prefix" "maybe_vex")
- (set_attr "ssememalign" "64")
(set_attr "mode" "V2DF")])
(define_insn "<mask_codefor>avx512f_cvtpd2dq512<mask_name><round_name>"
@@ -5751,7 +5747,6 @@
%vmovhps\t{%2, %0|%q0, %2}"
[(set_attr "isa" "noavx,avx,noavx,avx,*")
(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "orig,vex,orig,vex,maybe_vex")
(set_attr "mode" "V4SF,V4SF,V2SF,V2SF,V2SF")])
@@ -5797,7 +5792,6 @@
%vmovlps\t{%2, %H0|%H0, %2}"
[(set_attr "isa" "noavx,avx,noavx,avx,*")
(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "orig,vex,orig,vex,maybe_vex")
(set_attr "mode" "V4SF,V4SF,V2SF,V2SF,V2SF")])
@@ -6255,7 +6249,6 @@
%vmovhlps\t{%1, %d0|%d0, %1}
%vmovlps\t{%H1, %d0|%d0, %H1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "V2SF,V4SF,V2SF")])
@@ -6295,7 +6288,6 @@
%vmovlps\t{%2, %H0|%H0, %2}"
[(set_attr "isa" "noavx,avx,noavx,avx,*")
(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "orig,vex,orig,vex,maybe_vex")
(set_attr "mode" "V2SF,V2SF,V4SF,V4SF,V2SF")])
@@ -6310,7 +6302,6 @@
%vmovaps\t{%1, %0|%0, %1}
%vmovlps\t{%1, %d0|%d0, %q1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "V2SF,V4SF,V2SF")])
@@ -6350,7 +6341,6 @@
%vmovlps\t{%2, %0|%q0, %2}"
[(set_attr "isa" "noavx,avx,noavx,avx,*")
(set_attr "type" "sseshuf,sseshuf,ssemov,ssemov,ssemov")
- (set_attr "ssememalign" "64")
(set_attr "length_immediate" "1,1,*,*,*")
(set_attr "prefix" "orig,vex,orig,vex,maybe_vex")
(set_attr "mode" "V4SF,V4SF,V2SF,V2SF,V2SF")])
@@ -7492,7 +7482,6 @@
%vmovhpd\t{%1, %0|%q0, %1}"
[(set_attr "isa" "noavx,avx,sse3,noavx,avx,*")
(set_attr "type" "sselog,sselog,sselog,ssemov,ssemov,ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_data16" "*,*,*,1,*,1")
(set_attr "prefix" "orig,vex,maybe_vex,orig,vex,maybe_vex")
(set_attr "mode" "V2DF,V2DF,DF,V1DF,V1DF,V1DF")])
@@ -7652,7 +7641,6 @@
%vmovlpd\t{%2, %H0|%H0, %2}"
[(set_attr "isa" "noavx,avx,sse3,noavx,avx,*")
(set_attr "type" "sselog,sselog,sselog,ssemov,ssemov,ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_data16" "*,*,*,1,*,1")
(set_attr "prefix" "orig,vex,maybe_vex,orig,vex,maybe_vex")
(set_attr "mode" "V2DF,V2DF,DF,V1DF,V1DF,V1DF")])
@@ -8322,7 +8310,6 @@
movhlps\t{%1, %0|%0, %1}
movlps\t{%H1, %0|%0, %H1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "mode" "V2SF,V4SF,V2SF")])
;; Avoid combining registers from different units in a single alternative,
@@ -8410,7 +8397,6 @@
#"
[(set_attr "isa" "noavx,avx,noavx,avx,*,*,*")
(set_attr "type" "ssemov,ssemov,sselog,sselog,ssemov,fmov,imov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_data16" "1,*,*,*,*,*,*")
(set_attr "prefix" "orig,vex,orig,vex,*,*,*")
(set_attr "mode" "V1DF,V1DF,V2DF,V2DF,DF,DF,DF")])
@@ -8479,7 +8465,6 @@
(const_string "imov")
]
(const_string "ssemov")))
- (set_attr "ssememalign" "64")
(set_attr "prefix_data16" "*,1,*,*,*,*,1,*,*,*,*")
(set_attr "length_immediate" "*,*,*,*,*,1,*,*,*,*,*")
(set_attr "prefix" "maybe_vex,orig,vex,orig,vex,orig,orig,vex,*,*,*")
@@ -8524,7 +8509,6 @@
(const_string "1")
(const_string "*")))
(set_attr "length_immediate" "*,*,*,*,*,1,*,*,*")
- (set_attr "ssememalign" "64")
(set_attr "prefix" "orig,vex,orig,vex,maybe_vex,orig,orig,vex,maybe_vex")
(set_attr "mode" "DF,DF,V1DF,V1DF,V1DF,V2DF,V1DF,V1DF,V1DF")])
@@ -14567,7 +14551,6 @@
"TARGET_SSE4_1 && <mask_avx512bw_condition> && <mask_avx512vl_condition>"
"%vpmov<extsuffix>bw\t{%1, %0<mask_operand2>|%0<mask_operand2>, %q1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -14608,7 +14591,6 @@
"TARGET_SSE4_1 && <mask_avx512vl_condition>"
"%vpmov<extsuffix>bd\t{%1, %0<mask_operand2>|%0<mask_operand2>, %k1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "32")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -14644,7 +14626,6 @@
"TARGET_SSE4_1 && <mask_avx512vl_condition>"
"%vpmov<extsuffix>wd\t{%1, %0<mask_operand2>|%0<mask_operand2>, %q1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -14687,7 +14668,6 @@
"TARGET_SSE4_1 && <mask_avx512vl_condition>"
"%vpmov<extsuffix>bq\t{%1, %0<mask_operand2>|%0<mask_operand2>, %w1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "16")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -14725,7 +14705,6 @@
"TARGET_SSE4_1 && <mask_avx512vl_condition>"
"%vpmov<extsuffix>wq\t{%1, %0<mask_operand2>|%0<mask_operand2>, %k1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "32")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -14760,7 +14739,6 @@
"TARGET_SSE4_1 && <mask_avx512vl_condition>"
"%vpmov<extsuffix>dq\t{%1, %0<mask_operand2>|%0<mask_operand2>, %q1}"
[(set_attr "type" "ssemov")
- (set_attr "ssememalign" "64")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "mode" "TI")])
@@ -15048,7 +15026,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "memory" "none,load")
(set_attr "mode" "TI")])
@@ -15076,7 +15053,6 @@
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
(set_attr "prefix" "maybe_vex")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "btver2_decode" "vector")
(set_attr "memory" "none,load")
@@ -15104,7 +15080,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "btver2_decode" "vector")
@@ -15131,7 +15106,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "memory" "none,load,none,load")
(set_attr "btver2_decode" "vector,vector,vector,vector")
@@ -15185,7 +15159,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "memory" "none,load")
(set_attr "mode" "TI")])
@@ -15208,7 +15181,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "memory" "none,load")
@@ -15233,7 +15205,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "prefix" "maybe_vex")
(set_attr "memory" "none,load")
@@ -15258,7 +15229,6 @@
[(set_attr "type" "sselog")
(set_attr "prefix_data16" "1")
(set_attr "prefix_extra" "1")
- (set_attr "ssememalign" "8")
(set_attr "length_immediate" "1")
(set_attr "memory" "none,load,none,load")
(set_attr "prefix" "maybe_vex")
--
2.5.5