| From | Julien Thierry <> | Subject | [RFC v5 15/57] objtool: Support addition to set frame pointer | Date | Thu, 9 Jan 2020 16:02:18 +0000 |
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Support updating the frame pointer by adding an immediate value to the stack pointer in the CFA tracking code.
Signed-off-by: Julien Thierry <jthierry@redhat.com> --- tools/objtool/check.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 19e96c4ad0a3..5b2539eaccba 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1394,6 +1394,18 @@ static int update_insn_state(struct instruction *insn, struct insn_state *state) break; } + if (op->src.reg == CFI_SP && cfa->base == CFI_SP && + op->dest.reg == CFI_BP && + regs[CFI_BP].base == CFI_CFA && + regs[CFI_BP].offset == -cfa->offset + op->src.offset) { + + /* lea disp(%rsp), %rbp */ + cfa->base = CFI_BP; + cfa->offset -= op->src.offset; + state->bp_scratch = false; + break; + } + if (op->src.reg == CFI_SP && cfa->base == CFI_SP) { /* drap: lea disp(%rsp), %drap */ -- 2.21.0
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