[PATCH 0/2] powerpc: unrel_branch_check.sh: enable llvm-objdump

@@ -18,7 +18,7 @@ quiet_cmd_relocs_check = CHKREL  $@
 ifdef CONFIG_PPC_BOOK3S_64
       cmd_relocs_check =						\
 	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$(NM)" "$@" ; \
-	$(BASH) $(srctree)/arch/powerpc/tools/unrel_branch_check.sh "$(OBJDUMP)" "$@"
+	$(BASH) $(srctree)/arch/powerpc/tools/unrel_branch_check.sh "$(OBJDUMP)" "$(NM)" "$@"
 else
       cmd_relocs_check =						\
 	$(CONFIG_SHELL) $(srctree)/arch/powerpc/tools/relocs_check.sh "$(OBJDUMP)" "$(NM)" "$@"

@@ -5,18 +5,15 @@
 # This script checks the unrelocated code of a vmlinux for "suspicious"
 # branches to relocated code (head_64.S code).
 
-# Have Kbuild supply the path to objdump so we handle cross compilation.
+# Have Kbuild supply the path to objdump and nm so we handle cross compilation.
 objdump="$1"
-vmlinux="$2"
+nm="$2"
+vmlinux="$3"
 
-#__end_interrupts should be located within the first 64K
 kstart=0xc000000000000000
-printf -v kend '0x%x' $(( kstart + 0x10000 ))
 
-end_intr=0x$(
-$objdump -R -d --start-address="$kstart" --stop-address="$kend" "$vmlinux" 2>/dev/null |
-awk '$2 == "<__end_interrupts>:" { print $1 }'
-)
+end_intr=0x$($nm -p "$vmlinux" |
+	sed -E -n '/\s+[[:alpha:]]\s+__end_interrupts\s*$/{s///p;q}')
 if [ "$end_intr" = "0x" ]; then
 	exit 0
 fi

@@ -18,12 +18,16 @@ if [ "$end_intr" = "0x" ]; then
 	exit 0
 fi
 
-$objdump -R -D --no-show-raw-insn --start-address="$kstart" --stop-address="$end_intr" "$vmlinux" |
+# we know that there is a correct branch to
+# __start_initialization_multiplatform, so find its address
+# so we can exclude it.
+sim=0x$($nm -p "$vmlinux" |
+	sed -E -n '/\s+[[:alpha:]]\s+__start_initialization_multiplatform\s*$/{s///p;q}')
+
+$objdump -D --no-show-raw-insn --start-address="$kstart" --stop-address="$end_intr" "$vmlinux" |
 sed -E -n '
 # match lines that start with a kernel address
 /^c[0-9a-f]*:\s*b/ {
-	# drop a target that we do not care about
-	/\<__start_initialization_multiplatform>/d
 	# drop branches via ctr or lr
 	/\<b.?.?(ct|l)r/d
 	# cope with some differences between Clang and GNU objdumps

@@ -33,14 +37,34 @@ sed -E -n '
 	s/\s0x/ /
 	s/://
 	# format for the loop below
-	s/^(\S+)\s+(\S+)\s+(\S+)\s*(\S*).*$/\1:\2:0x\3:\4/
+	s/^(\S+)\s+(\S+)\s+(\S+)\s*(\S*).*$/\1:\2:\3:\4/
 	# strip out condition registers
-	s/:0xcr[0-7],/:0x/
+	s/:cr[0-7],/:/
 	p
 }' | {
 
 all_good=true
 while IFS=: read -r from branch to sym; do
+	case "$to" in
+	c*)	to="0x$to"
+		;;
+	.+*)
+		to=${to#.+}
+		if [ "$branch" = 'b' ]; then
+			if (( to >= 0x2000000 )); then
+				to=$(( to - 0x4000000 ))
+			fi
+		elif (( to >= 0x8000 )); then
+			to=$(( to - 0x10000 ))
+		fi
+		printf -v to '0x%x' $(( "0x$from" + to ))
+		;;
+	*)	printf 'Unkown branch format\n'
+		;;
+	esac
+	if [ "$to" = "$sim" ]; then
+		continue
+	fi
 	if (( to > end_intr )); then
 		if $all_good; then
 			printf '%s\n' 'WARNING: Unrelocated relative branches'