linux-kernel - [PATCH 4/4] ARM: backtrace: use more descriptive labels

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Message-Id: <20200730205112.2099429-5-ndesaulniers@google.com>
Date:   Thu, 30 Jul 2020 13:51:12 -0700
From:   Nick Desaulniers <ndesaulniers@...gle.com>
To:     Nathan Huckleberry <nhuck15@...il.com>,
        Russell King <linux@...linux.org.uk>
Cc:     Andrew Morton <akpm@...ux-foundation.org>,
        Chunyan Zhang <zhang.lyra@...il.com>,
        clang-built-linux@...glegroups.com,
        Dmitry Safonov <0x7f454c46@...il.com>,
        linux-arm-kernel@...ts.infradead.org, linux-kernel@...r.kernel.org,
        linux-mediatek@...ts.infradead.org,
        Lvqiang Huang <lvqiang.huang@...soc.com>,
        Matthias Brugger <matthias.bgg@...il.com>,
        Nick Desaulniers <ndesaulniers@...gle.com>,
        Miles Chen <miles.chen@...iatek.com>
Subject: [PATCH 4/4] ARM: backtrace: use more descriptive labels

We don't necessarily need the `b` suffixes used to disambiguate between
non-unique local labels. Give these labels more descriptive names.

Signed-off-by: Nick Desaulniers <ndesaulniers@...gle.com>
---
 arch/arm/lib/backtrace.S | 30 +++++++++++++++---------------
 1 file changed, 15 insertions(+), 15 deletions(-)

diff --git a/arch/arm/lib/backtrace.S b/arch/arm/lib/backtrace.S
index 872f658638d9..138e961ff033 100644
--- a/arch/arm/lib/backtrace.S
+++ b/arch/arm/lib/backtrace.S
@@ -37,9 +37,9 @@ ENDPROC(c_backtrace)
  THUMB(		orreq	mask, #0x03		)
 		movne	mask, #0		@ mask for 32-bit
 
-1:		stmfd	sp!, {pc}		@ calculate offset of PC stored
+store_pc:	stmfd	sp!, {pc}		@ calculate offset of PC stored
 		ldr	r0, [sp], #4		@ by stmfd for this CPU
-		adr	r1, 1b
+		adr	r1, store_pc
 		sub	offset, r0, r1
 
 /*
@@ -60,14 +60,14 @@ ENDPROC(c_backtrace)
 for_each_frame:	tst	frame, mask		@ Check for address exceptions
 		bne	no_frame
 
-1001:		ldr	sv_pc, [frame, #0]	@ get saved pc
-1002:		ldr	sv_fp, [frame, #-12]	@ get saved fp
+load_pc:	ldr	sv_pc, [frame, #0]	@ get saved pc
+load_fp:	ldr	sv_fp, [frame, #-12]	@ get saved fp
 
 		sub	sv_pc, sv_pc, offset	@ Correct PC for prefetching
 		bic	sv_pc, sv_pc, mask	@ mask PC/LR for the mode
 
-1003:		ldr	r2, [sv_pc, #-4]	@ if stmfd sp!, {args} exists,
-		ldr	r3, .Ldsi+4		@ adjust saved 'pc' back one
+load_stmfd:	ldr	r2, [sv_pc, #-4]	@ if stmfd sp!, {args} exists,
+		ldr	r3, .Lopcode + 4	@ adjust saved 'pc' back one
 		teq	r3, r2, lsr #11		@ instruction
 		subne	r0, sv_pc, #4		@ allow for mov
 		subeq	r0, sv_pc, #8		@ allow for mov + stmia
@@ -79,15 +79,15 @@ for_each_frame:	tst	frame, mask		@ Check for address exceptions
 		bl	dump_backtrace_entry
 
 		ldr	r1, [sv_pc, #-4]	@ if stmfd sp!, {args} exists,
-		ldr	r3, .Ldsi+4
+		ldr	r3, .Lopcode + 4
 		teq	r3, r1, lsr #11
 		ldreq	r0, [frame, #-8]	@ get sp
 		subeq	r0, r0, #4		@ point at the last arg
 		mov	r2, loglvl
 		bleq	dump_backtrace_stm	@ dump saved registers
 
-1004:		ldr	r1, [sv_pc, #0]		@ if stmfd sp!, {..., fp, ip, lr, pc}
-		ldr	r3, .Ldsi		@ instruction exists,
+reload_stmfd:	ldr	r1, [sv_pc, #0]		@ if stmfd sp!, {..., fp, ip, lr, pc}
+		ldr	r3, .Lopcode		@ instruction exists,
 		teq	r3, r1, lsr #11
 		subeq	r0, frame, #16
 		mov	r2, loglvl
@@ -100,7 +100,7 @@ for_each_frame:	tst	frame, mask		@ Check for address exceptions
 		mov	frame, sv_fp		@ above the current frame
 		bhi	for_each_frame
 
-1006:		adr	r0, .Lbad
+bad_frame:	adr	r0, .Lbad
 		mov	r1, loglvl
 		mov	r2, frame
 		bl	printk
@@ -109,15 +109,15 @@ ENDPROC(c_backtrace)
 		
 		.pushsection __ex_table,"a"
 		.align	3
-		.long	1001b, 1006b
-		.long	1002b, 1006b
-		.long	1003b, 1006b
-		.long	1004b, 1006b
+		.long	load_pc, bad_frame
+		.long	load_fp, bad_frame
+		.long	load_stmfd, bad_frame
+		.long	reload_stmfd, bad_frame
 		.popsection
 
 .Lbad:		.asciz	"%sBacktrace aborted due to bad frame pointer <%p>\n"
 		.align
-.Ldsi:		.word	0xe92dd800 >> 11	@ stmfd sp!, {... fp, ip, lr, pc}
+.Lopcode:	.word	0xe92dd800 >> 11	@ stmfd sp!, {... fp, ip, lr, pc}
 		.word	0xe92d0000 >> 11	@ stmfd sp!, {}
 
 #endif
-- 
2.28.0.163.g6104cc2f0b6-goog