Architectures without PUSH/POP instructions will always access the stack though memory operations (SRC/DEST_INDIRECT). Make those operations have the same effect on the CFA as PUSH/POP, with no stack pointer modification.
Signed-off-by: Julien Thierry <[email protected]> --- tools/objtool/check.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/tools/objtool/check.c b/tools/objtool/check.c index f45991c2db41..7ff87fa3caec 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -2005,6 +2005,13 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, break; case OP_SRC_REG_INDIRECT: + if (!cfi->drap && op->dest.reg == cfa->base) { + + /* mov disp(%rsp), %rbp */ + cfa->base = CFI_SP; + cfa->offset = cfi->stack_size; + } + if (cfi->drap && op->src.reg == CFI_BP && op->src.offset == cfi->drap_offset) { @@ -2026,6 +2033,11 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov disp(%rbp), %reg */ /* mov disp(%rsp), %reg */ restore_reg(cfi, op->dest.reg); + } else if (op->src.reg == CFI_SP && + op->src.offset == regs[op->dest.reg].offset + cfi->stack_size) { + + /* mov disp(%rsp), %reg */ + restore_reg(cfi, op->dest.reg); } break; @@ -2103,6 +2115,11 @@ static int update_cfi_state(struct instruction *insn, struct cfi_state *cfi, /* mov reg, disp(%rsp) */ save_reg(cfi, op->src.reg, CFI_CFA, op->dest.offset - cfi->cfa.offset); + } else if (op->dest.reg == CFI_SP) { + + /* mov reg, disp(%rsp) */ + save_reg(cfi, op->src.reg, CFI_CFA, + op->dest.offset - cfi->stack_size); } break; -- 2.21.3
