From cca4e4aec1fe52e5ecd15e3cebdbb36e2f254220 Mon Sep 17 00:00:00 2001
From: Wolfgang Denk <wd@denx.de>
Date: Tue, 1 Nov 2011 20:54:02 +0000
Subject: Reduce build times

U-Boot Makefiles contain a number of tests for compiler features etc.
which so far are executed again and again.  On some architectures
(especially ARM) this results in a large number of calls to gcc.

This patch makes sure to run such tests only once, thus largely
reducing the number of "execve" system calls.

Example: number of "execve" system calls for building the "P2020DS"
(Power Architecture) and "qong" (ARM) boards, measured as:
	-> strace -f -e trace=execve -o /tmp/foo ./MAKEALL <board>
	-> grep execve /tmp/foo | wc -l

	Before: After:	Reduction:
==================================
P2020DS 20555	15205	-26%
qong	31692	14490	-54%

As a result, built times are significantly reduced, typically by
30...50%.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Cc: Andy Fleming <afleming@gmail.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Albert Aribaud <albert.aribaud@free.fr>
cc: Graeme Russ <graeme.russ@gmail.com>
cc: Mike Frysinger <vapier@gentoo.org>
Tested-by: Graeme Russ <graeme.russ@gmail.com>
Tested-by: Matthias Weisser <weisserm@arcor.de>
Tested-by: Sanjeev Premi <premi@ti.com>
Tested-by: Simon Glass <sjg@chromium.org>
Tested-by: Macpaul Lin <macpaul@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
---
 arch/arm/config.mk | 19 ++++++++++---------
 1 file changed, 10 insertions(+), 9 deletions(-)

(limited to 'arch/arm/config.mk')

diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index 9b4e581b2d..45f9dca5d5 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -34,7 +34,7 @@ endif
 PLATFORM_CPPFLAGS += -DCONFIG_ARM -D__ARM__
 
 # Explicitly specifiy 32-bit ARM ISA since toolchain default can be -mthumb:
-PLATFORM_CPPFLAGS += $(call cc-option,-marm,)
+PF_CPPFLAGS_ARM := $(call cc-option,-marm,)
 
 # Try if EABI is supported, else fall back to old API,
 # i. e. for example:
@@ -44,15 +44,16 @@ PLATFORM_CPPFLAGS += $(call cc-option,-marm,)
 #	-mabi=apcs-gnu -mno-thumb-interwork
 # - with ELDK 3.1 (gcc 3.x), use:
 #	-mapcs-32 -mno-thumb-interwork
-PLATFORM_CPPFLAGS += $(call cc-option,\
-				-mabi=aapcs-linux -mno-thumb-interwork,\
+PF_CPPFLAGS_ABI := $(call cc-option,\
+			-mabi=aapcs-linux -mno-thumb-interwork,\
+			$(call cc-option,\
+				-mapcs-32,\
 				$(call cc-option,\
-					-mapcs-32,\
-					$(call cc-option,\
-						-mabi=apcs-gnu,\
-					)\
-				) $(call cc-option,-mno-thumb-interwork,)\
-			)
+					-mabi=apcs-gnu,\
+				)\
+			) $(call cc-option,-mno-thumb-interwork,)\
+		)
+PLATFORM_CPPFLAGS += $(PF_CPPFLAGS_ARM) $(PF_CPPFLAGS_ABI)
 
 # For EABI, make sure to provide raise()
 ifneq (,$(findstring -mabi=aapcs-linux,$(PLATFORM_CPPFLAGS)))
-- 
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