Re: [patch v2] Get rid of stack trampolines for nested functions (0/4)

[Eric Botcazou]

> On ia64 I get this regression:
> 
> FAIL: gcc.dg/Wtrampolines.c  (test for warnings, line 31)
> 
> Since ia64 never uses trampolines this is probably ok and the test
> should be adjusted.

This actually revealed a problem: the same regression should have appeared on 
PowerPC64/Linux (ELFv1 ABI) but it didn't because I botched the hookization of 
TARGET_CUSTOM_FUNCTION_DESCRIPTORS, which started as a good old macro:

/* Use custom descriptors instead of trampolines if not AIX or ELFv1.  */
#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS (DEFAULT_ABI != ABI_AIX)

doesn't work as intended on PowerPC64 because DEFAULT_ABI is a variable...

Corrective patch attached, tested on x86/Linux, x86-64/Linux, PowerPC/Linux, 
PowerPC64/Linux, IA-64/Linux and SPARC/Solaris, applied as obvious.


* config/i386/i386.h (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): Move to...
* config/i386/i386.c (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): ...here.
* config/ia64/ia64.h (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): Move to...
* config/ia64/ia64.c (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): ...here.
* config/rs6000/rs6000.h (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): Move
to...
* config/rs6000/rs6000.c (TARGET_CUSTOM_FUNCTION_DESCRIPTORS):...here.
(rs6000_option_override_internal): Clear it if ABI_AIX.
* config/sparc/sparc.h (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): Move
to...
* config/sparc/sparc.c (TARGET_CUSTOM_FUNCTION_DESCRIPTORS): ...here.
testsuite/
* gcc.dg/Wtrampolines.c: XFAIL warning on ia64-*-* and powerpc64-*-*.
* gnat.dg/trampoline4.adb: Minor tweak.

-- 
Eric BotcazouIndex: config/i386/i386.c
===
--- config/i386/i386.c	(revision 241222)
+++ config/i386/i386.c	(working copy)
@@ -50833,6 +50833,9 @@ ix86_addr_space_zero_address_valid (addr
 #undef TARGET_HARD_REGNO_SCRATCH_OK
 #define TARGET_HARD_REGNO_SCRATCH_OK ix86_hard_regno_scratch_ok
 
+#undef TARGET_CUSTOM_FUNCTION_DESCRIPTORS
+#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS 1
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 #include "gt-i386.h"
Index: config/i386/i386.h
===
--- config/i386/i386.h	(revision 241222)
+++ config/i386/i386.h	(working copy)
@@ -2666,9 +2666,6 @@ extern void debug_dispatch_window (int);
 
 #define TARGET_SUPPORTS_WIDE_INT 1
 
-/* Use custom descriptors instead of trampolines when possible.  */
-#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS 1
-
 /*
 Local variables:
 version-control: t
Index: config/ia64/ia64.c
===
--- config/ia64/ia64.c	(revision 241222)
+++ config/ia64/ia64.c	(working copy)
@@ -649,6 +649,9 @@ static const struct attribute_spec ia64_
 #undef TARGET_ATTRIBUTE_TAKES_IDENTIFIER_P
 #define TARGET_ATTRIBUTE_TAKES_IDENTIFIER_P ia64_attribute_takes_identifier_p
 
+#undef TARGET_CUSTOM_FUNCTION_DESCRIPTORS
+#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS 0
+
 struct gcc_target targetm = TARGET_INITIALIZER;
 
 /* Returns TRUE iff the target attribute indicated by ATTR_ID takes a plain
Index: config/ia64/ia64.h
===
--- config/ia64/ia64.h	(revision 241222)
+++ config/ia64/ia64.h	(working copy)
@@ -1715,7 +1715,4 @@ struct GTY(()) machine_function
 /* Switch on code for querying unit reservations.  */
 #define CPU_UNITS_QUERY 1
 
-/* IA-64 already uses descriptors for its standard calling sequence.  */
-#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS 0
-
 /* End of ia64.h */
Index: config/rs6000/rs6000.c
===
--- config/rs6000/rs6000.c	(revision 241222)
+++ config/rs6000/rs6000.c	(working copy)
@@ -1867,6 +1867,9 @@ static const struct attribute_spec rs600
 
 #undef TARGET_OPTAB_SUPPORTED_P
 #define TARGET_OPTAB_SUPPORTED_P rs6000_optab_supported_p
+
+#undef TARGET_CUSTOM_FUNCTION_DESCRIPTORS
+#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS 1
 
 
 /* Processor table.  */
@@ -4862,6 +4865,10 @@ rs6000_option_override_internal (bool gl
 	 Linux and Darwin ABIs at the moment.  For now, only AIX is fixed.  */
   if (DEFAULT_ABI == ABI_V4 || DEFAULT_ABI == ABI_DARWIN)
 	targetm.calls.split_complex_arg = NULL;
+
+  /* The AIX and ELFv1 ABIs define standard function descriptors.  */
+  if (DEFAULT_ABI == ABI_AIX)
+	targetm.calls.custom_function_descriptors = 0;
 }
 
   /* Initialize rs6000_cost with the appropriate target costs.  */
Index: config/rs6000/rs6000.h
===
--- config/rs6000/rs6000.h	(revision 241222)
+++ config/rs6000/rs6000.h	(working copy)
@@ -2922,9 +2922,6 @@ extern GTY(()) tree rs6000_builtin_decls
 
 #define TARGET_SUPPORTS_WIDE_INT 1
 
-/* Use custom descriptors instead of trampolines if not AIX or ELFv1.  */
-#define TARGET_CUSTOM_FUNCTION_DESCRIPTORS (DEFAULT_ABI != 

Re: [patch v2] Get rid of stack trampolines for nested functions (0/4)

[Eric Botcazou]

> On ia64 I get this regression:
> 
> FAIL: gcc.dg/Wtrampolines.c  (test for warnings, line 31)

I managed to miss it in the test results...

> Since ia64 never uses trampolines this is probably ok and the test
> should be adjusted.

Yes, will do, thanks for the heads up.

-- 
Eric Botcazou

Re: [patch v2] Get rid of stack trampolines for nested functions (0/4)

[Andreas Schwab]

On Okt 16 2016, Eric Botcazou  wrote:

>> this is the updated version of the patch initially posted at:
>>   https://gcc.gnu.org/ml/gcc-patches/2016-06/msg02016.html
>> It takes into account Jeff's remarks, both on the code and the
>> documentation.
>> 
>> As discussed, I'm going to split it into 4 parts: common infrastructure, Ada
>> front-end bits, individual back-end changes, testsuite.  It was
>> bootstrapped and regtested on x86_64-suse-linux but AdaCore has been using
>> it on native platforms (Linux, Windows, Solaris, etc) and various
>> architectures (x86, PowerPC, SPARC, ARM, etc) for years.
>
> I've installed part #1, #2, #4 and part #3 for x86, PowerPC, SPARC and IA-64.
> The PowerPC and SPARC bits as approved, the x86 and IA-64 bits as obvious.

On ia64 I get this regression:

FAIL: gcc.dg/Wtrampolines.c  (test for warnings, line 31)

Since ia64 never uses trampolines this is probably ok and the test
should be adjusted.

Andreas.

-- 
Andreas Schwab, SUSE Labs, sch...@suse.de
GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE  1748 E4D4 88E3 0EEA B9D7
"And now for something completely different."

Re: [patch v2] Get rid of stack trampolines for nested functions (0/4)

[Eric Botcazou]

> this is the updated version of the patch initially posted at:
>   https://gcc.gnu.org/ml/gcc-patches/2016-06/msg02016.html
> It takes into account Jeff's remarks, both on the code and the
> documentation.
> 
> As discussed, I'm going to split it into 4 parts: common infrastructure, Ada
> front-end bits, individual back-end changes, testsuite.  It was
> bootstrapped and regtested on x86_64-suse-linux but AdaCore has been using
> it on native platforms (Linux, Windows, Solaris, etc) and various
> architectures (x86, PowerPC, SPARC, ARM, etc) for years.

I've installed part #1, #2, #4 and part #3 for x86, PowerPC, SPARC and IA-64.
The PowerPC and SPARC bits as approved, the x86 and IA-64 bits as obvious.

This was tested on x86/Linux, x86-64/Linux, PowerPC/Linux, PowerPC64/Linux, 
IA-64/Linux, SPARC/Solaris and SPARC64/Solaris.

I'll repost the remaining bits for Aarch64, ARM, Alpha, MIPS and HP-PA.

-- 
Eric Botcazou

[patch v2] Get rid of stack trampolines for nested functions (0/4)

[Eric Botcazou]

Hi,

this is the updated version of the patch initially posted at:
  https://gcc.gnu.org/ml/gcc-patches/2016-06/msg02016.html
It takes into account Jeff's remarks, both on the code and the documentation.

As discussed, I'm going to split it into 4 parts: common infrastructure, Ada 
front-end bits, individual back-end changes, testsuite.  It was bootstrapped 
and regtested on x86_64-suse-linux but AdaCore has been using it on native 
platforms (Linux, Windows, Solaris, etc) and various architectures (x86, 
PowerPC, SPARC, ARM, etc) for years.

 ada/gcc-interface/misc.c  |2 
 ada/gcc-interface/trans.c |   40 +++-
 builtins.c|   62 +
 builtins.def  |2 
 calls.c   |  101 +++---
 cfgexpand.c   |1 
 common.opt|5 +
 config/aarch64/aarch64.h  |4 
 config/alpha/alpha.h  |3 
 config/arm/arm.c  |   27 +-
 config/arm/arm.h  |4 
 config/i386/i386.h|3 
 config/ia64/ia64.h|3 
 config/mips/mips.h|4 
 config/pa/pa.h|3 
 config/rs6000/rs6000.h|3 
 config/sparc/sparc.h  |3 
 defaults.h|   11 ++
 doc/invoke.texi   |   24 +
 doc/tm.texi   |   18 
 doc/tm.texi.in|2 
 gimple.c  |4 
 gimple.h  |   21 
 langhooks-def.h   |2 
 langhooks.h   |4 
 rtl.h |5 +
 rtlanal.c |3 
 target.def|   19 
 testsuite/gnat.dg/trampoline3.adb |   22 
 testsuite/gnat.dg/trampoline4.adb |   23 +
 tree-core.h   |9 ++
 tree-nested.c |  169 ++--
 tree.c|9 +-
 tree.h|   10 ++
 34 files changed, 574 insertions(+), 51 deletions(-)

-- 
Eric Botcazou