+ kbuild-simpler-generation-of-assembly-constants.patch added to -mm tree

* + kbuild-simpler-generation-of-assembly-constants.patch added to -mm tree
@ 2016-07-08 21:05 akpm
  2016-07-13 17:36 ` [PATCH v3] kbuild: simpler generation of assembly constants Alexey Dobriyan
  0 siblings, 1 reply; 3+ messages in thread
From: akpm @ 2016-07-08 21:05 UTC (permalink / raw)
  To: adobriyan, mmarek, tony.luck, mm-commits


The patch titled
     Subject: kbuild: simpler generation of assembly constants
has been added to the -mm tree.  Its filename is
     kbuild-simpler-generation-of-assembly-constants.patch

This patch should soon appear at
    http://ozlabs.org/~akpm/mmots/broken-out/kbuild-simpler-generation-of-assembly-constants.patch
and later at
    http://ozlabs.org/~akpm/mmotm/broken-out/kbuild-simpler-generation-of-assembly-constants.patch

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------------------------------------------------------
From: Alexey Dobriyan <adobriyan@gmail.com>
Subject: kbuild: simpler generation of assembly constants

gcc doesn't really look inside "asm" statements and more or less directly
emits it into assembly.  So pretend "#define" is CPU instruction.

Also, use C++ comment to block whatever garbage is put at the end of
the line by compiler.

Link: http://lkml.kernel.org/r/20160707213941.GA31678@p183.telecom.by
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Michal Marek <mmarek@suse.cz>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 Kbuild                    |   12 +-----------
 arch/ia64/kernel/Makefile |    8 +-------
 include/linux/kbuild.h    |    2 +-
 scripts/mod/Makefile      |   11 +----------
 4 files changed, 4 insertions(+), 29 deletions(-)

diff -puN Kbuild~kbuild-simpler-generation-of-assembly-constants Kbuild

--- a/Kbuild~kbuild-simpler-generation-of-assembly-constants
+++ a/Kbuild
@@ -7,14 +7,6 @@
 # 4) Check for missing system calls
 # 5) Generate constants.py (may need bounds.h)
 
-# Default sed regexp - multiline due to syntax constraints
-define sed-y
-	"/^->/{s:->#\(.*\):/* \1 */:; \
-	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
-	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
-	s:->::; p;}"
-endef
-
 # Use filechk to avoid rebuilds when a header changes, but the resulting file
 # does not
 define filechk_offsets
@@ -26,9 +18,7 @@ define filechk_offsets
 	 echo " *"; \
 	 echo " * This file was generated by Kbuild"; \
 	 echo " */"; \
-	 echo ""; \
-	 sed -ne $(sed-y); \
-	 echo ""; \
+	 sed -ne '/#define/{s/\$$//;s/#//2;p;}'; \
 	 echo "#endif" )
 endef
 
diff -puN arch/ia64/kernel/Makefile~kbuild-simpler-generation-of-assembly-constants arch/ia64/kernel/Makefile
--- a/arch/ia64/kernel/Makefile~kbuild-simpler-generation-of-assembly-constants
+++ a/arch/ia64/kernel/Makefile
@@ -50,10 +50,6 @@ CFLAGS_traps.o  += -mfixed-range=f2-f5,f
 # The gate DSO image is built using a special linker script.
 include $(src)/Makefile.gate
 
-# Calculate NR_IRQ = max(IA64_NATIVE_NR_IRQS, XEN_NR_IRQS, ...) based on config
-define sed-y
-	"/^->/{s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; s:->::; p;}"
-endef
 quiet_cmd_nr_irqs = GEN     $@
 define cmd_nr_irqs
 	(set -e; \
@@ -65,9 +61,7 @@ define cmd_nr_irqs
 	 echo " * This file was generated by Kbuild"; \
 	 echo " *"; \
 	 echo " */"; \
-	 echo ""; \
-	 sed -ne $(sed-y) $<; \
-	 echo ""; \
+	 sed -ne '/#define/{s/\$$//;s/#//2;p;}' $<; \
 	 echo "#endif" ) > $@
 endef
 
diff -puN include/linux/kbuild.h~kbuild-simpler-generation-of-assembly-constants include/linux/kbuild.h
--- a/include/linux/kbuild.h~kbuild-simpler-generation-of-assembly-constants
+++ a/include/linux/kbuild.h
@@ -2,7 +2,7 @@
 #define __LINUX_KBUILD_H
 
 #define DEFINE(sym, val) \
-        asm volatile("\n->" #sym " %0 " #val : : "i" (val))
+	asm volatile ("#define " #sym " %0 //" #val :: "i" (val))
 
 #define BLANK() asm volatile("\n->" : : )
 
diff -puN scripts/mod/Makefile~kbuild-simpler-generation-of-assembly-constants scripts/mod/Makefile
--- a/scripts/mod/Makefile~kbuild-simpler-generation-of-assembly-constants
+++ a/scripts/mod/Makefile
@@ -7,13 +7,6 @@ modpost-objs	:= modpost.o file2alias.o s
 
 devicetable-offsets-file := devicetable-offsets.h
 
-define sed-y
-	"/^->/{s:->#\(.*\):/* \1 */:; \
-	s:^->\([^ ]*\) [\$$#]*\([-0-9]*\) \(.*\):#define \1 \2 /* \3 */:; \
-	s:^->\([^ ]*\) [\$$#]*\([^ ]*\) \(.*\):#define \1 \2 /* \3 */:; \
-	s:->::; p;}"
-endef

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