[U-Boot] [PATCH V3 1/2] [NEXT] arm: change relocation flag from -fPIC to -fPIE

[Albert Aribaud]

Replace GOT indirect addressing with more efficient pic-base
relative addressing for initialized data (uninitialized data
still use GOTi indirect addressing).  This also reduces code
size by 0.4% compared to -fPIC.

Signed-off-by: Albert Aribaud <albert.aribaud at free.fr>
---
SUMMARY

This patch aims at optimizing relocatable code both in size and
speed. The first patch switches from '-fPIC' to '-fPIE', which makes
initialized data accesses pc-relative rather than GOT-indirect, and
the second adds '-msingle-pic-base' which factors out GOT addressing
by computing it once and for all.

PATCHSET HISTORY

V1	Initial submission
V2	Compute RAM pic base only if actually relocating
	Fixed RAM pic base computation and copy loop
V3	Added fix for tx25

 arch/arm/config.mk |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index 6923f6d..138c43a 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -35,7 +35,7 @@ endif
 
 ifndef CONFIG_SYS_ARM_WITHOUT_RELOC
 # needed for relocation
-PLATFORM_RELFLAGS += -fPIC
+PLATFORM_RELFLAGS += -fPIE
 endif
 
 ifdef CONFIG_SYS_ARM_WITHOUT_RELOC
-- 
1.7.0.4