Re: [PATCH] Turn on LRA on all targets

Re: [PATCH] Turn on LRA on all targets

[Roger Sayle]

Segher Boessenkool wrote:
> I send this patch now so that people can start testing.
>
> diff --git a/gcc/config/nvptx/nvptx.cc b/gcc/config/nvptx/nvptx.cc
> index 89349dae9e62..e32f17377525 100644
> --- a/gcc/config/nvptx/nvptx.cc
> +++ b/gcc/config/nvptx/nvptx.cc
> @@ -7601,9 +7601,6 @@ nvptx_asm_output_def_from_decls (FILE *stream, tree
name, tree value)
> #undef TARGET_ATTRIBUTE_TABLE
> #define TARGET_ATTRIBUTE_TABLE nvptx_attribute_table
>
>-#undef TARGET_LRA_P
>-#define TARGET_LRA_P hook_bool_void_false
>-
> #undef TARGET_LEGITIMATE_ADDRESS_P
> #define TARGET_LEGITIMATE_ADDRESS_P nvptx_legitimate_address_p


I've tested Segher's patch on nvptx-none with make and make -k check and
can confirm there are no new regressions.  Nvptx is unique in that it
doesn't
use register allocation, i.e. GCC's only TARGET_NO_REGISTER_ALLOCATION
target,
so it's a little odd that it specifies which register allocator it doesn't
use.

I hope this helps,
Roger
--

Re: [PATCH] Turn on LRA on all targets

[Jeff Law]

On 4/29/23 07:37, Roger Sayle wrote:
> 
> Segher Boessenkool wrote:
>> I send this patch now so that people can start testing.
>>
>> diff --git a/gcc/config/nvptx/nvptx.cc b/gcc/config/nvptx/nvptx.cc
>> index 89349dae9e62..e32f17377525 100644
>> --- a/gcc/config/nvptx/nvptx.cc
>> +++ b/gcc/config/nvptx/nvptx.cc
>> @@ -7601,9 +7601,6 @@ nvptx_asm_output_def_from_decls (FILE *stream, tree
> name, tree value)
>> #undef TARGET_ATTRIBUTE_TABLE
>> #define TARGET_ATTRIBUTE_TABLE nvptx_attribute_table
>>
>> -#undef TARGET_LRA_P
>> -#define TARGET_LRA_P hook_bool_void_false
>> -
>> #undef TARGET_LEGITIMATE_ADDRESS_P
>> #define TARGET_LEGITIMATE_ADDRESS_P nvptx_legitimate_address_p
> 
> 
> I've tested Segher's patch on nvptx-none with make and make -k check and
> can confirm there are no new regressions.  Nvptx is unique in that it
> doesn't
> use register allocation, i.e. GCC's only TARGET_NO_REGISTER_ALLOCATION
> target,
> so it's a little odd that it specifies which register allocator it doesn't
> use.
> 
> I hope this helps,
It does.  Consider a patch which flips the nvptx port to LRA as 
pre-approved.

I tried the FRV just for fun.  It faulted all over the place :(

jeff

Flip the nvptx port to LRA (was: [PATCH] Turn on LRA on all targets)

[Thomas Schwinge]

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Hi!

On 2023-04-29T09:06:54-0600, Jeff Law via Gcc-patches <gcc-patches@gcc.gnu.org> wrote:
> On 4/29/23 07:37, Roger Sayle wrote:
>>
>> Segher Boessenkool wrote:
>>> I send this patch now so that people can start testing.
>>>
>>> --- a/gcc/config/nvptx/nvptx.cc
>>> +++ b/gcc/config/nvptx/nvptx.cc
>>> @@ -7601,9 +7601,6 @@ nvptx_asm_output_def_from_decls (FILE *stream, tree name, tree value)
>>> #undef TARGET_ATTRIBUTE_TABLE
>>> #define TARGET_ATTRIBUTE_TABLE nvptx_attribute_table
>>>
>>> -#undef TARGET_LRA_P
>>> -#define TARGET_LRA_P hook_bool_void_false
>>> -
>>> #undef TARGET_LEGITIMATE_ADDRESS_P
>>> #define TARGET_LEGITIMATE_ADDRESS_P nvptx_legitimate_address_p
>>
>> I've tested Segher's patch on nvptx-none with make and make -k check and
>> can confirm there are no new regressions.

Confirmed.  Also, no change in nvptx target libraries built.  As
expected.

>> Nvptx is unique in that it
>> doesn't
>> use register allocation, i.e. GCC's only TARGET_NO_REGISTER_ALLOCATION
>> target,
>> so it's a little odd that it specifies which register allocator it doesn't
>> use.
>>
>> I hope this helps,
>
> It does.  Consider a patch which flips the nvptx port to LRA as
> pre-approved.

Pushed to master branch commit f7e3123638712773e8c01e17aae9dc64d9342016
"Flip the nvptx port to LRA", see attached.


Grüße
 Thomas


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From f7e3123638712773e8c01e17aae9dc64d9342016 Mon Sep 17 00:00:00 2001
From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Sun, 23 Apr 2023 16:47:52 +0000
Subject: [PATCH] Flip the nvptx port to LRA

... understanding that "turn on LRA" is an exaggeration here, given that nvptx
isn't actually doing register allocation ('TARGET_NO_REGISTER_ALLOCATION').

	gcc/
	* config/nvptx/nvptx.cc (TARGET_LRA_P): Remove.

Co-authored-by: Thomas Schwinge <thomas@codesourcery.com>
---
 gcc/config/nvptx/nvptx.cc | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/gcc/config/nvptx/nvptx.cc b/gcc/config/nvptx/nvptx.cc
index e3b0304d5376..16ed78030d73 100644
--- a/gcc/config/nvptx/nvptx.cc
+++ b/gcc/config/nvptx/nvptx.cc
@@ -7633,9 +7633,6 @@ nvptx_asm_output_def_from_decls (FILE *stream, tree name, tree value)
 #undef TARGET_ATTRIBUTE_TABLE
 #define TARGET_ATTRIBUTE_TABLE nvptx_attribute_table
 
-#undef TARGET_LRA_P
-#define TARGET_LRA_P hook_bool_void_false
-
 #undef TARGET_LEGITIMATE_ADDRESS_P
 #define TARGET_LEGITIMATE_ADDRESS_P nvptx_legitimate_address_p
 
-- 
2.39.2