[PATCH v6 04/33] objtool: arm64: Decode jump and call related instructions

From: Chen Zhongjin
Date: Wed Jun 22 2022 - 21:52:29 EST


Decode branch, branch and link (aarch64's call) and return instructions.

Signed-off-by: Julien Thierry <jthierry@xxxxxxxxxx>
Signed-off-by: Chen Zhongjin <chenzhongjin@xxxxxxxxxx>
---
tools/objtool/arch/arm64/decode.c | 21 +++++++++++++++++++++
1 file changed, 21 insertions(+)

diff --git a/tools/objtool/arch/arm64/decode.c b/tools/objtool/arch/arm64/decode.c
index d8c32703874d..40ada17d0842 100644
--- a/tools/objtool/arch/arm64/decode.c
+++ b/tools/objtool/arch/arm64/decode.c
@@ -212,6 +212,27 @@ int arch_decode_instruction(struct objtool_file *file, const struct section *sec
}
}
break;
+ case AARCH64_INSN_CLS_BR_SYS:
+ if (aarch64_insn_is_ret(insn) &&
+ aarch64_insn_decode_register(AARCH64_INSN_REGTYPE_RN, insn)
+ == AARCH64_INSN_REG_LR) {
+ *type = INSN_RETURN;
+ } else if (aarch64_insn_is_bl(insn)) {
+ *type = INSN_CALL;
+ *immediate = aarch64_get_branch_offset(insn);
+ } else if (aarch64_insn_is_blr(insn)) {
+ *type = INSN_CALL_DYNAMIC;
+ } else if (aarch64_insn_is_b(insn)) {
+ *type = INSN_JUMP_UNCONDITIONAL;
+ *immediate = aarch64_get_branch_offset(insn);
+ } else if (aarch64_insn_is_br(insn)) {
+ *type = INSN_JUMP_DYNAMIC;
+ } else if (aarch64_insn_is_branch_imm(insn)) {
+ /* Remaining branch opcodes are conditional */
+ *type = INSN_JUMP_CONDITIONAL;
+ *immediate = aarch64_get_branch_offset(insn);
+ }
+ break;
default:
break;
}
--
2.17.1