Re: [PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
On 06/13/2018 04:02 AM, Jeff Law wrote:
On 05/21/2018 07:55 AM, marxin wrote:
gcc/ChangeLog:
2017-04-18 Denys Vlasenko
* config/i386/i386-common.c (ix86_handle_option): Remove support
for obsolete -malign-loops, -malign-jumps and -malign-functions
options.
* config/i386/i386.opt: Likewise.
The ChangeLog doesn't seem match the actual changes. I think this patch
is more about using the additional info that's potentially provided by
the -falign options to drive backend decisions and dropping the
secondary alignment request.
Hi.
Exactly.
The change seems to consistently do:
(1<<(LOG)))-1)
Which needs some horizontal whitespace.
Fixed in updated version of the patch.
Martin
The meat of the changes seem fairly reasonable.
jeff
>From d4e3c9f6438dd665a5e1802c625dbbd7742cb52f Mon Sep 17 00:00:00 2001
From: marxin
Date: Mon, 21 May 2018 15:55:09 +0200
Subject: [PATCH] Temporary remove "at least 8 byte alignment" code from x86
gcc/ChangeLog:
2017-04-18 Denys Vlasenko
* config/i386/dragonfly.h: (ASM_OUTPUT_MAX_SKIP_ALIGN):
Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gas.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/lynx.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/netbsd-elf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
* config/i386/freebsd.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Remove "If N
is large, do at least 8 byte alignment" code. Add SUBALIGN_LOG
define. Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gnu-user.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/iamcu.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/openbsdelf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
---
gcc/config/i386/dragonfly.h | 10 ++
gcc/config/i386/freebsd.h| 16 +---
gcc/config/i386/gas.h| 12 +++-
gcc/config/i386/gnu-user.h | 16 +---
gcc/config/i386/i386.h | 2 +-
gcc/config/i386/iamcu.h | 16 +---
gcc/config/i386/lynx.h | 6 --
gcc/config/i386/netbsd-elf.h | 6 --
gcc/config/i386/openbsdelf.h | 16 +---
gcc/config/i386/x86-64.h | 16 ++--
10 files changed, 48 insertions(+), 68 deletions(-)
diff --git a/gcc/config/i386/dragonfly.h b/gcc/config/i386/dragonfly.h
index a05b36435de..40774c0cf7a 100644
--- a/gcc/config/i386/dragonfly.h
+++ b/gcc/config/i386/dragonfly.h
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
- if ((LOG) != 0) { \
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) { \
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1 << (LOG)) - 1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else\
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
diff --git a/gcc/config/i386/freebsd.h b/gcc/config/i386/freebsd.h
index 0f38e6d859a..caac6b38575 100644
--- a/gcc/config/i386/freebsd.h
+++ b/gcc/config/i386/freebsd.h
@@ -92,25 +92,19 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1 << (LOG)) - 1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else\
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1)\
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE));\
- } \
} \
} while (0)
#endif
diff --git a/gcc/config/i386/gas.h b/gcc/config/i386/gas.h
index 25d5f7809b5..e149ab1360c 100644
--- a/gcc/config/i386/gas.h
+++ b/gcc/config/i386/gas.h
@@ -57,7 +57,7 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_BALIGN_AND_P2ALIGN
#undef ASM_OUTPUT_ALIGN
#define ASM_OUTPUT_ALIGN(FILE,LOG) \
- if ((LOG)!=0) fprintf ((FILE), "\t.balign %d\n", 1<<(LOG))
+ if ((LOG)!=0) fprintf ((FILE), "\t.balign %d\n", 1 << (LOG))
#endif
/* A C statement to output to the stdio stream FILE an assembler
@@ -68,10 +68,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0
Re: [PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
On 05/21/2018 07:55 AM, marxin wrote: > > gcc/ChangeLog: > > 2017-04-18 Denys Vlasenko > > * config/i386/i386-common.c (ix86_handle_option): Remove support > for obsolete -malign-loops, -malign-jumps and -malign-functions > options. > * config/i386/i386.opt: Likewise. The ChangeLog doesn't seem match the actual changes. I think this patch is more about using the additional info that's potentially provided by the -falign options to drive backend decisions and dropping the secondary alignment request. The change seems to consistently do: (1<<(LOG)))-1) Which needs some horizontal whitespace. The meat of the changes seem fairly reasonable. jeff
[PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
gcc/ChangeLog:
2017-04-18 Denys Vlasenko
* config/i386/i386-common.c (ix86_handle_option): Remove support
for obsolete -malign-loops, -malign-jumps and -malign-functions
options.
* config/i386/i386.opt: Likewise.
---
gcc/config/i386/dragonfly.h | 10 ++
gcc/config/i386/freebsd.h| 16 +---
gcc/config/i386/gas.h| 10 ++
gcc/config/i386/gnu-user.h | 16 +---
gcc/config/i386/i386.h | 2 +-
gcc/config/i386/iamcu.h | 16 +---
gcc/config/i386/lynx.h | 6 --
gcc/config/i386/netbsd-elf.h | 6 --
gcc/config/i386/openbsdelf.h | 16 +---
gcc/config/i386/x86-64.h | 16 ++--
10 files changed, 47 insertions(+), 67 deletions(-)
diff --git a/gcc/config/i386/dragonfly.h b/gcc/config/i386/dragonfly.h
index a05b36435de..5432af9aa01 100644
--- a/gcc/config/i386/dragonfly.h
+++ b/gcc/config/i386/dragonfly.h
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
- if ((LOG) != 0) { \
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) { \
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else\
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
diff --git a/gcc/config/i386/freebsd.h b/gcc/config/i386/freebsd.h
index 0f38e6d859a..40f7a21dfd6 100644
--- a/gcc/config/i386/freebsd.h
+++ b/gcc/config/i386/freebsd.h
@@ -92,25 +92,19 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else\
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1)\
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE));\
- } \
} \
} while (0)
#endif
diff --git a/gcc/config/i386/gas.h b/gcc/config/i386/gas.h
index 25d5f7809b5..e86c10588b8 100644
--- a/gcc/config/i386/gas.h
+++ b/gcc/config/i386/gas.h
@@ -68,10 +68,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0) { \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else\
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+}
#endif
/* A C statement or statements which output an assembler instruction
diff --git a/gcc/config/i386/gnu-user.h b/gcc/config/i386/gnu-user.h
index d1dad685e72..7c4d40c2eae 100644
--- a/gcc/config/i386/gnu-user.h
+++ b/gcc/config/i386/gnu-user.h
@@ -95,24 +95,18 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else\
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1)\
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE));\
- } \
} \
} while (0)
#endif
diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 6ee99d36207..2da01394478 100644
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -2220,7 +2220,7 @@ extern int const svr4_dbx_register_map[FIRST_PSEUDO_REGISTER];
#define ASM_OUTPUT_MAX_SKIP_PAD(FILE, LOG, MAX_SKIP) \
if ((LOG) != 0) \
{ \
- if ((MAX_SKIP) == 0) \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
else\
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
diff --git a/gcc/config/i386/iamcu.h b/gcc/config/i386/iamcu.h
index b30132f377a..07ecbec60d3 100644
--- a/gcc/config/i386/iamcu.h
+++ b/gcc/config/i386/iamcu.h
@@ -62,23 +62,17 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
/* A C stateme
[PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
This change drops forced alignment to 8 if requested alignment is higher
than 8: before the patch, -falign-functions=9 was generating
.p2align 4,,8
.p2align 3
which means: "align to 16 if the skip is 8 bytes or less; else align to 8".
After this change, ".p2align 3" is not emitted.
This behavior will be implemented differently by the next patch.
The new SUBALIGN_LOG define will be used by the next patch.
While we are here, avoid generating ".p2align N,,2^N-1" -
it is functionally equivalent to ".p2align N". In this case, use the latter.
2017-04-18 Denys Vlasenko
* config/i386/dragonfly.h: (ASM_OUTPUT_MAX_SKIP_ALIGN):
Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gas.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/lynx.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/netbsd-elf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
* config/i386/freebsd.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Remove "If N
is large, do at least 8 byte alignment" code. Add SUBALIGN_LOG
define. Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gnu-user.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/iamcu.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/openbsdelf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
Index: gcc/config/i386/dragonfly.h
===
--- gcc/config/i386/dragonfly.h (revision 239860)
+++ gcc/config/i386/dragonfly.h (working copy)
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respect
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP)
\
- if ((LOG) != 0) {
\
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) {\
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
Index: gcc/config/i386/freebsd.h
===
--- gcc/config/i386/freebsd.h (revision 239860)
+++ gcc/config/i386/freebsd.h (working copy)
@@ -92,9 +92,9 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1) \
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE)); \
- }
\
} \
} while (0)
#endif
Index: gcc/config/i386/gas.h
===
--- gcc/config/i386/gas.h (revision 239860)
+++ gcc/config/i386/gas.h (working copy)
@@ -72,10 +72,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0) { \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+}
#endif
/* A C statement or statements which output an assembler instruction
Index: gcc/config/i386/gnu-user.h
===
--- gcc/config/i386/gnu-user.h (revision 239860
[PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
This change drops forced alignment to 8 if requested alignment is higher
than 8: before the patch, -falign-functions=9 was generating
.p2align 4,,8
.p2align 3
which means: "align to 16 if the skip is 8 bytes or less; else align to 8".
After this change, ".p2align 3" is not emitted.
This behavior will be implemented differently by the next patch.
The new SUBALIGN_LOG define will be used by the next patch.
While we are here, avoid generating ".p2align N,,2^N-1" -
it is functionally equivalent to ".p2align N". In this case, use the latter.
2016-09-27 Denys Vlasenko
* config/i386/dragonfly.h: (ASM_OUTPUT_MAX_SKIP_ALIGN):
Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gas.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/lynx.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/netbsd-elf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
* config/i386/freebsd.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Remove "If N
is large, do at least 8 byte alignment" code. Add SUBALIGN_LOG
define. Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gnu-user.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/iamcu.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/openbsdelf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
Index: gcc/config/i386/dragonfly.h
===
--- gcc/config/i386/dragonfly.h (revision 239860)
+++ gcc/config/i386/dragonfly.h (working copy)
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respect
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP)
\
- if ((LOG) != 0) {
\
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) {\
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
Index: gcc/config/i386/freebsd.h
===
--- gcc/config/i386/freebsd.h (revision 239860)
+++ gcc/config/i386/freebsd.h (working copy)
@@ -92,9 +92,9 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1) \
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE)); \
- }
\
} \
} while (0)
#endif
Index: gcc/config/i386/gas.h
===
--- gcc/config/i386/gas.h (revision 239860)
+++ gcc/config/i386/gas.h (working copy)
@@ -72,10 +72,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0) { \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+}
#endif
/* A C statement or statements which output an assembler instruction
Index: gcc/config/i386/gnu-user.h
===
--- gcc/config/i386/gnu-user.h (revision 239860
[PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
This change drops forced alignment to 8 if requested alignment is higher
than 8: before the patch, -falign-functions=9 was generating
.p2align 4,,8
.p2align 3
which means: "align to 16 if the skip is 8 bytes or less; else align to 8".
After this change, ".p2align 3" is not emitted.
This behavior will be implemented differently by the next patch.
The new SUBALIGN_LOG define will be used by the next patch.
While we are here, avoid generating ".p2align N,,2^N-1" -
it is functionally equivalent to ".p2align N". In this case, use the latter.
2016-09-27 Denys Vlasenko
* config/i386/dragonfly.h: (ASM_OUTPUT_MAX_SKIP_ALIGN):
Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gas.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/lynx.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/netbsd-elf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
* config/i386/freebsd.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Remove "If N
is large, do at least 8 byte alignment" code. Add SUBALIGN_LOG
define. Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gnu-user.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/iamcu.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/openbsdelf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
Index: gcc/config/i386/dragonfly.h
===
--- gcc/config/i386/dragonfly.h (revision 239860)
+++ gcc/config/i386/dragonfly.h (working copy)
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respect
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP)
\
- if ((LOG) != 0) {
\
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) {\
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
Index: gcc/config/i386/freebsd.h
===
--- gcc/config/i386/freebsd.h (revision 239860)
+++ gcc/config/i386/freebsd.h (working copy)
@@ -92,9 +92,9 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1) \
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE)); \
- }
\
} \
} while (0)
#endif
Index: gcc/config/i386/gas.h
===
--- gcc/config/i386/gas.h (revision 239860)
+++ gcc/config/i386/gas.h (working copy)
@@ -72,10 +72,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0) { \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+}
#endif
/* A C statement or statements which output an assembler instruction
Index: gcc/config/i386/gnu-user.h
===
--- gcc/config/i386/gnu-user.h (revision 239860
[PATCH 2/3] Temporary remove "at least 8 byte alignment" code from x86
This change drops forced alignment to 8 if requested alignment is higher
than 8: before the patch, -falign-functions=9 was generating
.p2align 4,,8
.p2align 3
which means: "align to 16 if the skip is 8 bytes or less; else align to 8".
After this change, ".p2align 3" is not emitted.
This behavior will be implemented differently by the next patch.
The new SUBALIGN_LOG define will be used by the next patch.
While we are here, avoid generating ".p2align N,,2^N-1" -
it is functionally equivalent to ".p2align N". In this case, use the latter.
2016-09-27 Denys Vlasenko
* config/i386/dragonfly.h: (ASM_OUTPUT_MAX_SKIP_ALIGN):
Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gas.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/lynx.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/netbsd-elf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/i386.h (ASM_OUTPUT_MAX_SKIP_PAD): Likewise.
* config/i386/freebsd.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Remove "If N
is large, do at least 8 byte alignment" code. Add SUBALIGN_LOG
define. Use a simpler align directive also if MAXSKIP = ALIGN-1.
* config/i386/gnu-user.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/iamcu.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/openbsdelf.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
* config/i386/x86-64.h (ASM_OUTPUT_MAX_SKIP_ALIGN): Likewise.
Index: gcc/config/i386/dragonfly.h
===
--- gcc/config/i386/dragonfly.h (revision 239860)
+++ gcc/config/i386/dragonfly.h (working copy)
@@ -69,10 +69,12 @@ see the files COPYING3 and COPYING.RUNTIME respect
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
#undef ASM_OUTPUT_MAX_SKIP_ALIGN
-#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP)
\
- if ((LOG) != 0) {
\
-if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
-else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+#define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE, LOG, MAX_SKIP) \
+ if ((LOG) != 0) {\
+if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
}
#endif
Index: gcc/config/i386/freebsd.h
===
--- gcc/config/i386/freebsd.h (revision 239860)
+++ gcc/config/i386/freebsd.h (working copy)
@@ -92,9 +92,9 @@ along with GCC; see the file COPYING3. If not see
/* A C statement to output to the stdio stream FILE an assembler
command to advance the location counter to a multiple of 1<= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- /* Make sure that we have at least 8 byte alignment if > 8 byte \
- alignment is preferred. */ \
- if ((LOG) > 3 \
- && (1 << (LOG)) > ((MAX_SKIP) + 1) \
- && (MAX_SKIP) >= 7) \
- fputs ("\t.p2align 3\n", (FILE)); \
- }
\
} \
} while (0)
#endif
Index: gcc/config/i386/gas.h
===
--- gcc/config/i386/gas.h (revision 239860)
+++ gcc/config/i386/gas.h (working copy)
@@ -72,10 +72,12 @@ along with GCC; see the file COPYING3. If not see
#ifdef HAVE_GAS_MAX_SKIP_P2ALIGN
# define ASM_OUTPUT_MAX_SKIP_ALIGN(FILE,LOG,MAX_SKIP) \
- if ((LOG) != 0) {\
- if ((MAX_SKIP) == 0) fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
- else fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
- }
+if ((LOG) != 0) { \
+ if ((MAX_SKIP) == 0 || (MAX_SKIP) >= (1<<(LOG))-1) \
+ fprintf ((FILE), "\t.p2align %d\n", (LOG)); \
+ else \
+ fprintf ((FILE), "\t.p2align %d,,%d\n", (LOG), (MAX_SKIP)); \
+}
#endif
/* A C statement or statements which output an assembler instruction
Index: gcc/config/i386/gnu-user.h
===
--- gcc/config/i386/gnu-user.h (revision 239860
