Commit 2a512829 authored by Peter Zijlstra's avatar Peter Zijlstra
Browse files

objtool,x86: Additionally decode: mov %rsp, (%reg) 



Where we already decode: mov %rsp, %reg, also decode mov %rsp, (%reg).

Nothing should match for this new stack-op.

Signed-off-by: default avatarPeter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: default avatarMiroslav Benes <mbenes@suse.cz>
Acked-by: default avatarJosh Poimboeuf <jpoimboe@redhat.com>
parent 87ccc826

tools/objtool/arch/x86/decode.c

+34 −8
Original line number Diff line number Diff line
@@ -222,8 +222,9 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, 
		break;



	case 0x89:

		if (rex_w && !rex_r && modrm_mod == 3 && modrm_reg == 4) {

		if (rex_w && !rex_r && modrm_reg == 4) {



			if (modrm_mod == 3) {

				/* mov %rsp, reg */

				ADD_OP(op) {

					op->src.type = OP_SRC_REG;
@@ -232,6 +233,28 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, 
					op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b];

				}

				break;



			} else {

				/* skip nontrivial SIB */

				if (modrm_rm == 4 && !(sib == 0x24 && rex_b == rex_x))

					break;



				/* skip RIP relative displacement */

				if (modrm_rm == 5 && modrm_mod == 0)

					break;



				/* mov %rsp, disp(%reg) */

				ADD_OP(op) {

					op->src.type = OP_SRC_REG;

					op->src.reg = CFI_SP;

					op->dest.type = OP_DEST_REG_INDIRECT;

					op->dest.reg = op_to_cfi_reg[modrm_rm][rex_b];

					op->dest.offset = insn.displacement.value;

				}

				break;

			}



			break;

		}



		if (rex_w && !rex_b && modrm_mod == 3 && modrm_rm == 4) {
@@ -259,8 +282,10 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, 
				op->dest.reg = CFI_BP;

				op->dest.offset = insn.displacement.value;

			}

			break;

		}



		} else if (rex_w && !rex_b && modrm_rm == 4 && sib == 0x24) {

		if (rex_w && !rex_b && modrm_rm == 4 && sib == 0x24) {



			/* mov reg, disp(%rsp) */

			ADD_OP(op) {
@@ -270,6 +295,7 @@ int arch_decode_instruction(const struct elf *elf, const struct section *sec, 
				op->dest.reg = CFI_SP;

				op->dest.offset = insn.displacement.value;

			}

			break;

		}



		break;