From fbf87b1823dd5ebc2a384711ea2c677543019ece Mon Sep 17 00:00:00 2001 From: Albert ARIBAUD Date: Tue, 11 Jun 2013 14:17:35 +0200 Subject: [PATCH] arm: optimize relocate_code routine MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Use section symbols directly Drop support for R_ARM_ABS32 record types Eliminate unneeded intermediate registers Optimize relocation table iteration Signed-off-by: Albert ARIBAUD Tested-by: Lubomir Popov Tested-by: Jeroen Hofstee Reviewed-by: Benoît Thébaudeau --- arch/arm/lib/relocate.S | 32 ++++++++++++-------------------- 1 file changed, 12 insertions(+), 20 deletions(-) diff --git a/arch/arm/lib/relocate.S b/arch/arm/lib/relocate.S index 3f444c1..949b9e8 100644 --- a/arch/arm/lib/relocate.S +++ b/arch/arm/lib/relocate.S @@ -37,19 +37,15 @@ */ ENTRY(relocate_code) - mov r6, r0 /* save addr of destination */ - - ldr r0, =__image_copy_start /* r0 <- SRC &__image_copy_start */ - subs r9, r6, r0 /* r9 <- relocation offset */ + ldr r1, =__image_copy_start /* r1 <- SRC &__image_copy_start */ + subs r9, r0, r1 /* r9 <- relocation offset */ beq relocate_done /* skip relocation */ - mov r1, r6 /* r1 <- scratch for copy loop */ - adr r7, relocate_code /* r7 <- SRC &relocate_code */ ldr r2, =__image_copy_end /* r2 <- SRC &__image_copy_end */ copy_loop: - ldmia r0!, {r10-r11} /* copy from source address [r0] */ - stmia r1!, {r10-r11} /* copy to target address [r1] */ - cmp r0, r2 /* until source end address [r2] */ + ldmia r1!, {r10-r11} /* copy from source address [r1] */ + stmia r0!, {r10-r11} /* copy to target address [r0] */ + cmp r1, r2 /* until source end address [r2] */ blo copy_loop /* @@ -58,21 +54,17 @@ copy_loop: ldr r2, =__rel_dyn_start /* r2 <- SRC &__rel_dyn_start */ ldr r3, =__rel_dyn_end /* r3 <- SRC &__rel_dyn_end */ fixloop: - ldr r0, [r2] /* r0 <- SRC location to fix up */ - add r0, r0, r9 /* r0 <- DST location to fix up */ - ldr r1, [r2, #4] - and r7, r1, #0xff - cmp r7, #23 /* relative fixup? */ - beq fixrel - /* ignore unknown type of fixup */ - b fixnext -fixrel: + ldmia r2!, {r0-r1} /* (r0,r1) <- (SRC location,fixup) */ + and r1, r1, #0xff + cmp r1, #23 /* relative fixup? */ + bne fixnext + /* relative fix: increase location by offset */ + add r0, r0, r9 ldr r1, [r0] add r1, r1, r9 -fixnext: str r1, [r0] - add r2, r2, #8 /* each rel.dyn entry is 8 bytes */ +fixnext: cmp r2, r3 blo fixloop -- 2.7.4