Resguardo inicial

linux-7.2.3/tools/objtool/arch/loongarch/Build

@@ -0,0 +1,3 @@
+objtool-y += decode.o
+objtool-y += special.o
+objtool-y += orc.o

linux-7.2.3/tools/objtool/arch/loongarch/decode.c

@@ -0,0 +1,439 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <objtool/check.h>
+#include <objtool/disas.h>
+#include <objtool/warn.h>
+#include <asm/inst.h>
+#include <asm/orc_types.h>
+#include <linux/objtool_types.h>
+#include <arch/elf.h>
+
+const char *arch_reg_name[CFI_NUM_REGS] = {
+	"zero", "ra", "tp", "sp",
+	"a0", "a1", "a2", "a3",
+	"a4", "a5", "a6", "a7",
+	"t0", "t1", "t2", "t3",
+	"t4", "t5", "t6", "t7",
+	"t8", "u0", "fp", "s0",
+	"s1", "s2", "s3", "s4",
+	"s5", "s6", "s7", "s8"
+};
+
+int arch_ftrace_match(const char *name)
+{
+	return !strcmp(name, "_mcount");
+}
+
+unsigned long arch_jump_destination(struct instruction *insn)
+{
+	return insn->offset + (insn->immediate << 2);
+}
+
+s64 arch_insn_adjusted_addend(struct instruction *insn, struct reloc *reloc)
+{
+	return reloc_addend(reloc);
+}
+
+bool arch_pc_relative_reloc(struct reloc *reloc)
+{
+	return false;
+}
+
+bool arch_callee_saved_reg(unsigned char reg)
+{
+	switch (reg) {
+	case CFI_RA:
+	case CFI_FP:
+	case CFI_S0 ... CFI_S8:
+		return true;
+	default:
+		return false;
+	}
+}
+
+int arch_decode_hint_reg(u8 sp_reg, int *base)
+{
+	switch (sp_reg) {
+	case ORC_REG_UNDEFINED:
+		*base = CFI_UNDEFINED;
+		break;
+	case ORC_REG_SP:
+		*base = CFI_SP;
+		break;
+	case ORC_REG_FP:
+		*base = CFI_FP;
+		break;
+	default:
+		return -1;
+	}
+
+	return 0;
+}
+
+static bool is_loongarch(const struct elf *elf)
+{
+	if (elf->ehdr.e_machine == EM_LOONGARCH)
+		return true;
+
+	ERROR("unexpected ELF machine type %d", elf->ehdr.e_machine);
+	return false;
+}
+
+#define ADD_OP(op) \
+	if (!(op = calloc(1, sizeof(*op)))) \
+		return -1; \
+	else for (*ops_list = op, ops_list = &op->next; op; op = NULL)
+
+static bool decode_insn_reg0i26_fomat(union loongarch_instruction inst,
+				      struct instruction *insn)
+{
+	switch (inst.reg0i26_format.opcode) {
+	case b_op:
+		insn->type = INSN_JUMP_UNCONDITIONAL;
+		insn->immediate = sign_extend64(inst.reg0i26_format.immediate_h << 16 |
+						inst.reg0i26_format.immediate_l, 25);
+		break;
+	case bl_op:
+		insn->type = INSN_CALL;
+		insn->immediate = sign_extend64(inst.reg0i26_format.immediate_h << 16 |
+						inst.reg0i26_format.immediate_l, 25);
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static bool decode_insn_reg1i21_fomat(union loongarch_instruction inst,
+				      struct instruction *insn)
+{
+	switch (inst.reg1i21_format.opcode) {
+	case beqz_op:
+	case bnez_op:
+	case bceqz_op:
+		insn->type = INSN_JUMP_CONDITIONAL;
+		insn->immediate = sign_extend64(inst.reg1i21_format.immediate_h << 16 |
+						inst.reg1i21_format.immediate_l, 20);
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static bool decode_insn_reg2i12_fomat(union loongarch_instruction inst,
+				      struct instruction *insn,
+				      struct stack_op **ops_list,
+				      struct stack_op *op)
+{
+	switch (inst.reg2i12_format.opcode) {
+	case addid_op:
+		if ((inst.reg2i12_format.rd == CFI_SP) || (inst.reg2i12_format.rj == CFI_SP)) {
+			/* addi.d sp,sp,si12 or addi.d fp,sp,si12 or addi.d sp,fp,si12 */
+			insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11);
+			ADD_OP(op) {
+				op->src.type = OP_SRC_ADD;
+				op->src.reg = inst.reg2i12_format.rj;
+				op->src.offset = insn->immediate;
+				op->dest.type = OP_DEST_REG;
+				op->dest.reg = inst.reg2i12_format.rd;
+			}
+		}
+		if ((inst.reg2i12_format.rd == CFI_SP) && (inst.reg2i12_format.rj == CFI_FP)) {
+			/* addi.d sp,fp,si12 */
+			struct symbol *func = find_func_containing(insn->sec, insn->offset);
+
+			if (!func)
+				return false;
+
+			func->frame_pointer = true;
+		}
+		break;
+	case ldd_op:
+		if (inst.reg2i12_format.rj == CFI_SP) {
+			/* ld.d rd,sp,si12 */
+			insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11);
+			ADD_OP(op) {
+				op->src.type = OP_SRC_REG_INDIRECT;
+				op->src.reg = CFI_SP;
+				op->src.offset = insn->immediate;
+				op->dest.type = OP_DEST_REG;
+				op->dest.reg = inst.reg2i12_format.rd;
+			}
+		}
+		break;
+	case std_op:
+		if (inst.reg2i12_format.rj == CFI_SP) {
+			/* st.d rd,sp,si12 */
+			insn->immediate = sign_extend64(inst.reg2i12_format.immediate, 11);
+			ADD_OP(op) {
+				op->src.type = OP_SRC_REG;
+				op->src.reg = inst.reg2i12_format.rd;
+				op->dest.type = OP_DEST_REG_INDIRECT;
+				op->dest.reg = CFI_SP;
+				op->dest.offset = insn->immediate;
+			}
+		}
+		break;
+	case andi_op:
+		if (inst.reg2i12_format.rd == 0 &&
+		    inst.reg2i12_format.rj == 0 &&
+		    inst.reg2i12_format.immediate == 0)
+			/* andi r0,r0,0 */
+			insn->type = INSN_NOP;
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static bool decode_insn_reg2i14_fomat(union loongarch_instruction inst,
+				      struct instruction *insn,
+				      struct stack_op **ops_list,
+				      struct stack_op *op)
+{
+	switch (inst.reg2i14_format.opcode) {
+	case ldptrd_op:
+		if (inst.reg2i14_format.rj == CFI_SP) {
+			/* ldptr.d rd,sp,si14 */
+			insn->immediate = sign_extend64(inst.reg2i14_format.immediate, 13);
+			ADD_OP(op) {
+				op->src.type = OP_SRC_REG_INDIRECT;
+				op->src.reg = CFI_SP;
+				op->src.offset = insn->immediate;
+				op->dest.type = OP_DEST_REG;
+				op->dest.reg = inst.reg2i14_format.rd;
+			}
+		}
+		break;
+	case stptrd_op:
+		if (inst.reg2i14_format.rj == CFI_SP) {
+			/* stptr.d ra,sp,0 */
+			if (inst.reg2i14_format.rd == LOONGARCH_GPR_RA &&
+			    inst.reg2i14_format.immediate == 0)
+				break;
+
+			/* stptr.d rd,sp,si14 */
+			insn->immediate = sign_extend64(inst.reg2i14_format.immediate, 13);
+			ADD_OP(op) {
+				op->src.type = OP_SRC_REG;
+				op->src.reg = inst.reg2i14_format.rd;
+				op->dest.type = OP_DEST_REG_INDIRECT;
+				op->dest.reg = CFI_SP;
+				op->dest.offset = insn->immediate;
+			}
+		}
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static bool decode_insn_reg2i16_fomat(union loongarch_instruction inst,
+				      struct instruction *insn)
+{
+	switch (inst.reg2i16_format.opcode) {
+	case jirl_op:
+		if (inst.reg2i16_format.rd == 0 &&
+		    inst.reg2i16_format.rj == CFI_RA &&
+		    inst.reg2i16_format.immediate == 0) {
+			/* jirl r0,ra,0 */
+			insn->type = INSN_RETURN;
+		} else if (inst.reg2i16_format.rd == CFI_RA) {
+			/* jirl ra,rj,offs16 */
+			insn->type = INSN_CALL_DYNAMIC;
+		} else if (inst.reg2i16_format.rd == CFI_A0 &&
+			   inst.reg2i16_format.immediate == 0) {
+			/*
+			 * jirl a0,t0,0
+			 * this is a special case in loongarch_suspend_enter,
+			 * just treat it as a call instruction.
+			 */
+			insn->type = INSN_CALL_DYNAMIC;
+		} else if (inst.reg2i16_format.rd == 0 &&
+			   inst.reg2i16_format.immediate == 0) {
+			/* jirl r0,rj,0 */
+			insn->type = INSN_JUMP_DYNAMIC;
+		} else if (inst.reg2i16_format.rd == 0 &&
+			   inst.reg2i16_format.immediate != 0) {
+			/*
+			 * jirl r0,t0,12
+			 * this is a rare case in JUMP_VIRT_ADDR,
+			 * just ignore it due to it is harmless for tracing.
+			 */
+			break;
+		} else {
+			/* jirl rd,rj,offs16 */
+			insn->type = INSN_JUMP_UNCONDITIONAL;
+			insn->immediate = sign_extend64(inst.reg2i16_format.immediate, 15);
+		}
+		break;
+	case beq_op:
+	case bne_op:
+	case blt_op:
+	case bge_op:
+	case bltu_op:
+	case bgeu_op:
+		insn->type = INSN_JUMP_CONDITIONAL;
+		insn->immediate = sign_extend64(inst.reg2i16_format.immediate, 15);
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+static bool decode_insn_reg3_fomat(union loongarch_instruction inst,
+				   struct instruction *insn)
+{
+	switch (inst.reg3_format.opcode) {
+	case amswapw_op:
+		if (inst.reg3_format.rd == LOONGARCH_GPR_ZERO &&
+		    inst.reg3_format.rk == LOONGARCH_GPR_RA &&
+		    inst.reg3_format.rj == LOONGARCH_GPR_ZERO) {
+			/* amswap.w $zero, $ra, $zero */
+			insn->type = INSN_BUG;
+		}
+		break;
+	default:
+		return false;
+	}
+
+	return true;
+}
+
+int arch_decode_instruction(struct objtool_file *file, const struct section *sec,
+			    unsigned long offset, unsigned int maxlen,
+			    struct instruction *insn)
+{
+	struct stack_op **ops_list = &insn->stack_ops;
+	const struct elf *elf = file->elf;
+	struct stack_op *op = NULL;
+	union loongarch_instruction inst;
+
+	if (!is_loongarch(elf))
+		return -1;
+
+	if (maxlen < LOONGARCH_INSN_SIZE)
+		return 0;
+
+	insn->len = LOONGARCH_INSN_SIZE;
+	insn->type = INSN_OTHER;
+	insn->immediate = 0;
+
+	inst = *(union loongarch_instruction *)(sec->data->d_buf + offset);
+
+	if (decode_insn_reg0i26_fomat(inst, insn))
+		return 0;
+	if (decode_insn_reg1i21_fomat(inst, insn))
+		return 0;
+	if (decode_insn_reg2i12_fomat(inst, insn, ops_list, op))
+		return 0;
+	if (decode_insn_reg2i14_fomat(inst, insn, ops_list, op))
+		return 0;
+	if (decode_insn_reg2i16_fomat(inst, insn))
+		return 0;
+	if (decode_insn_reg3_fomat(inst, insn))
+		return 0;
+
+	if (inst.word == 0) {
+		/* andi $zero, $zero, 0x0 */
+		insn->type = INSN_NOP;
+	} else if (inst.reg0i15_format.opcode == break_op &&
+		   inst.reg0i15_format.immediate == 0x0) {
+		/* break 0x0 */
+		insn->type = INSN_TRAP;
+	} else if (inst.reg0i15_format.opcode == break_op &&
+		   inst.reg0i15_format.immediate == 0x1) {
+		/* break 0x1 */
+		insn->type = INSN_BUG;
+	} else if (inst.reg2_format.opcode == ertn_op) {
+		/* ertn */
+		insn->type = INSN_RETURN;
+	}
+
+	return 0;
+}
+
+const char *arch_nop_insn(int len)
+{
+	static u32 nop;
+
+	if (len != LOONGARCH_INSN_SIZE) {
+		ERROR("invalid NOP size: %d\n", len);
+		return NULL;
+	}
+
+	nop = LOONGARCH_INSN_NOP;
+
+	return (const char *)&nop;
+}
+
+const char *arch_ret_insn(int len)
+{
+	static u32 ret;
+
+	if (len != LOONGARCH_INSN_SIZE) {
+		ERROR("invalid RET size: %d\n", len);
+		return NULL;
+	}
+
+	emit_jirl((union loongarch_instruction *)&ret, LOONGARCH_GPR_RA, LOONGARCH_GPR_ZERO, 0);
+
+	return (const char *)&ret;
+}
+
+void arch_initial_func_cfi_state(struct cfi_init_state *state)
+{
+	int i;
+
+	for (i = 0; i < CFI_NUM_REGS; i++) {
+		state->regs[i].base = CFI_UNDEFINED;
+		state->regs[i].offset = 0;
+	}
+
+	/* initial CFA (call frame address) */
+	state->cfa.base = CFI_SP;
+	state->cfa.offset = 0;
+}
+
+unsigned int arch_reloc_size(struct reloc *reloc)
+{
+	switch (reloc_type(reloc)) {
+	case R_LARCH_32:
+	case R_LARCH_32_PCREL:
+		return 4;
+	default:
+		return 8;
+	}
+}
+
+unsigned long arch_jump_table_sym_offset(struct reloc *reloc, struct reloc *table)
+{
+	switch (reloc_type(reloc)) {
+	case R_LARCH_32_PCREL:
+	case R_LARCH_64_PCREL:
+		return reloc->sym->offset + reloc_addend(reloc) -
+		       (reloc_offset(reloc) - reloc_offset(table));
+	default:
+		return reloc->sym->offset + reloc_addend(reloc);
+	}
+}
+
+#ifdef DISAS
+
+int arch_disas_info_init(struct disassemble_info *dinfo)
+{
+	return disas_info_init(dinfo, bfd_arch_loongarch,
+			       bfd_mach_loongarch32, bfd_mach_loongarch64,
+			       NULL);
+}
+
+#endif /* DISAS */

linux-7.2.3/tools/objtool/arch/loongarch/include/arch/cfi_regs.h

@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_CFI_REGS_H
+#define _OBJTOOL_ARCH_CFI_REGS_H
+
+#define CFI_RA		1
+#define CFI_SP		3
+#define CFI_A0		4
+#define CFI_FP		22
+#define CFI_S0		23
+#define CFI_S1		24
+#define CFI_S2		25
+#define CFI_S3		26
+#define CFI_S4		27
+#define CFI_S5		28
+#define CFI_S6		29
+#define CFI_S7		30
+#define CFI_S8		31
+#define CFI_NUM_REGS	32
+
+#define CFI_BP		CFI_FP
+
+#endif /* _OBJTOOL_ARCH_CFI_REGS_H */

linux-7.2.3/tools/objtool/arch/loongarch/include/arch/elf.h

@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_ELF_H
+#define _OBJTOOL_ARCH_ELF_H
+
+/*
+ * See the following link for more info about ELF Relocation types:
+ * https://loongson.github.io/LoongArch-Documentation/LoongArch-ELF-ABI-EN.html#_relocations
+ */
+#ifndef R_LARCH_NONE
+#define R_LARCH_NONE		0
+#endif
+#ifndef R_LARCH_32
+#define R_LARCH_32		1
+#endif
+#ifndef R_LARCH_64
+#define R_LARCH_64		2
+#endif
+#ifndef R_LARCH_32_PCREL
+#define R_LARCH_32_PCREL	99
+#endif
+#ifndef R_LARCH_64_PCREL
+#define R_LARCH_64_PCREL	109
+#endif
+
+#ifndef EM_LOONGARCH
+#define EM_LOONGARCH		258
+#endif
+
+#define R_NONE			R_LARCH_NONE
+#define R_ABS32			R_LARCH_32
+#define R_ABS64			R_LARCH_64
+#define R_DATA32		R_LARCH_32_PCREL
+#define R_DATA64		R_LARCH_32_PCREL
+#define R_TEXT32		R_LARCH_32_PCREL
+#define R_TEXT64		R_LARCH_32_PCREL
+
+#endif /* _OBJTOOL_ARCH_ELF_H */

linux-7.2.3/tools/objtool/arch/loongarch/include/arch/special.h

@@ -0,0 +1,33 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+#ifndef _OBJTOOL_ARCH_SPECIAL_H
+#define _OBJTOOL_ARCH_SPECIAL_H
+
+/*
+ * See more info about struct exception_table_entry
+ * in arch/loongarch/include/asm/extable.h
+ */
+#define EX_ENTRY_SIZE		12
+#define EX_ORIG_OFFSET		0
+#define EX_NEW_OFFSET		4
+
+/*
+ * See more info about struct jump_entry
+ * in include/linux/jump_label.h
+ */
+#define JUMP_ENTRY_SIZE		16
+#define JUMP_ORIG_OFFSET	0
+#define JUMP_NEW_OFFSET		4
+#define JUMP_KEY_OFFSET		8
+
+/*
+ * See more info about struct alt_instr
+ * in arch/loongarch/include/asm/alternative.h
+ */
+#define ALT_ENTRY_SIZE		12
+#define ALT_ORIG_OFFSET		0
+#define ALT_NEW_OFFSET		4
+#define ALT_FEATURE_OFFSET	8
+#define ALT_ORIG_LEN_OFFSET	10
+#define ALT_NEW_LEN_OFFSET	11
+
+#endif /* _OBJTOOL_ARCH_SPECIAL_H */

linux-7.2.3/tools/objtool/arch/loongarch/orc.c

@@ -0,0 +1,170 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <linux/objtool_types.h>
+#include <asm/orc_types.h>
+
+#include <objtool/check.h>
+#include <objtool/orc.h>
+#include <objtool/warn.h>
+
+int init_orc_entry(struct orc_entry *orc, struct cfi_state *cfi, struct instruction *insn)
+{
+	struct cfi_reg *fp = &cfi->regs[CFI_FP];
+	struct cfi_reg *ra = &cfi->regs[CFI_RA];
+
+	memset(orc, 0, sizeof(*orc));
+
+	if (!cfi) {
+		/*
+		 * This is usually either unreachable nops/traps (which don't
+		 * trigger unreachable instruction warnings), or
+		 * STACK_FRAME_NON_STANDARD functions.
+		 */
+		orc->type = ORC_TYPE_UNDEFINED;
+		return 0;
+	}
+
+	switch (cfi->type) {
+	case UNWIND_HINT_TYPE_UNDEFINED:
+		orc->type = ORC_TYPE_UNDEFINED;
+		return 0;
+	case UNWIND_HINT_TYPE_END_OF_STACK:
+		orc->type = ORC_TYPE_END_OF_STACK;
+		return 0;
+	case UNWIND_HINT_TYPE_CALL:
+		orc->type = ORC_TYPE_CALL;
+		break;
+	case UNWIND_HINT_TYPE_REGS:
+		orc->type = ORC_TYPE_REGS;
+		break;
+	case UNWIND_HINT_TYPE_REGS_PARTIAL:
+		orc->type = ORC_TYPE_REGS_PARTIAL;
+		break;
+	default:
+		ERROR_INSN(insn, "unknown unwind hint type %d", cfi->type);
+		return -1;
+	}
+
+	orc->signal = cfi->signal;
+
+	switch (cfi->cfa.base) {
+	case CFI_SP:
+		orc->sp_reg = ORC_REG_SP;
+		break;
+	case CFI_FP:
+		orc->sp_reg = ORC_REG_FP;
+		break;
+	default:
+		ERROR_INSN(insn, "unknown CFA base reg %d", cfi->cfa.base);
+		return -1;
+	}
+
+	switch (fp->base) {
+	case CFI_UNDEFINED:
+		orc->fp_reg = ORC_REG_UNDEFINED;
+		orc->fp_offset = 0;
+		break;
+	case CFI_CFA:
+		orc->fp_reg = ORC_REG_PREV_SP;
+		orc->fp_offset = fp->offset;
+		break;
+	case CFI_FP:
+		orc->fp_reg = ORC_REG_FP;
+		break;
+	default:
+		ERROR_INSN(insn, "unknown FP base reg %d", fp->base);
+		return -1;
+	}
+
+	switch (ra->base) {
+	case CFI_UNDEFINED:
+		orc->ra_reg = ORC_REG_UNDEFINED;
+		orc->ra_offset = 0;
+		break;
+	case CFI_CFA:
+		orc->ra_reg = ORC_REG_PREV_SP;
+		orc->ra_offset = ra->offset;
+		break;
+	case CFI_FP:
+		orc->ra_reg = ORC_REG_FP;
+		break;
+	default:
+		ERROR_INSN(insn, "unknown RA base reg %d", ra->base);
+		return -1;
+	}
+
+	orc->sp_offset = cfi->cfa.offset;
+
+	return 0;
+}
+
+int write_orc_entry(struct elf *elf, struct section *orc_sec,
+		    struct section *ip_sec, unsigned int idx,
+		    struct section *insn_sec, unsigned long insn_off,
+		    struct orc_entry *o)
+{
+	struct orc_entry *orc;
+
+	/* populate ORC data */
+	orc = (struct orc_entry *)orc_sec->data->d_buf + idx;
+	memcpy(orc, o, sizeof(*orc));
+
+	/* populate reloc for ip */
+	if (!elf_init_reloc_text_sym(elf, ip_sec, idx * sizeof(int), idx,
+				     insn_sec, insn_off))
+		return -1;
+
+	return 0;
+}
+
+static const char *reg_name(unsigned int reg)
+{
+	switch (reg) {
+	case ORC_REG_SP:
+		return "sp";
+	case ORC_REG_FP:
+		return "fp";
+	case ORC_REG_PREV_SP:
+		return "prevsp";
+	default:
+		return "?";
+	}
+}
+
+static const char *orc_type_name(unsigned int type)
+{
+	switch (type) {
+	case UNWIND_HINT_TYPE_CALL:
+		return "call";
+	case UNWIND_HINT_TYPE_REGS:
+		return "regs";
+	case UNWIND_HINT_TYPE_REGS_PARTIAL:
+		return "regs (partial)";
+	default:
+		return "?";
+	}
+}
+
+static void print_reg(unsigned int reg, int offset)
+{
+	if (reg == ORC_REG_UNDEFINED)
+		printf(" (und) ");
+	else
+		printf("%s + %3d", reg_name(reg), offset);
+
+}
+
+void orc_print_dump(struct elf *dummy_elf, struct orc_entry *orc, int i)
+{
+	printf("type:%s", orc_type_name(orc[i].type));
+
+	printf(" sp:");
+	print_reg(orc[i].sp_reg, orc[i].sp_offset);
+
+	printf(" fp:");
+	print_reg(orc[i].fp_reg, orc[i].fp_offset);
+
+	printf(" ra:");
+	print_reg(orc[i].ra_reg, orc[i].ra_offset);
+
+	printf(" signal:%d\n", orc[i].signal);
+}

linux-7.2.3/tools/objtool/arch/loongarch/special.c

@@ -0,0 +1,201 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <objtool/special.h>
+#include <objtool/warn.h>
+
+bool arch_support_alt_relocation(struct special_alt *special_alt,
+				 struct instruction *insn,
+				 struct reloc *reloc)
+{
+	return false;
+}
+
+struct table_info {
+	struct list_head jump_info;
+	unsigned long insn_offset;
+	unsigned long rodata_offset;
+};
+
+static void get_rodata_table_size_by_table_annotate(struct objtool_file *file,
+						    struct instruction *insn,
+						    unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+	struct list_head table_list;
+	struct table_info *orig_table;
+	struct table_info *next_table;
+	unsigned long tmp_insn_offset;
+	unsigned long tmp_rodata_offset;
+	bool is_valid_list = false;
+
+	rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate");
+	if (!rsec)
+		return;
+
+	INIT_LIST_HEAD(&table_list);
+
+	for_each_reloc(rsec, reloc) {
+		if (reloc->sym->sec->rodata)
+			continue;
+
+		if (strcmp(insn->sec->name, reloc->sym->sec->name))
+			continue;
+
+		orig_table = malloc(sizeof(struct table_info));
+		if (!orig_table) {
+			WARN("malloc failed");
+			return;
+		}
+
+		orig_table->insn_offset = reloc->sym->offset + reloc_addend(reloc);
+		reloc++;
+		orig_table->rodata_offset = reloc->sym->offset + reloc_addend(reloc);
+
+		list_add_tail(&orig_table->jump_info, &table_list);
+
+		if (reloc_idx(reloc) + 1 == sec_num_entries(rsec))
+			break;
+
+		if (strcmp(insn->sec->name, (reloc + 1)->sym->sec->name)) {
+			list_for_each_entry(orig_table, &table_list, jump_info) {
+				if (orig_table->insn_offset == insn->offset) {
+					is_valid_list = true;
+					break;
+				}
+			}
+
+			if (!is_valid_list) {
+				list_del_init(&table_list);
+				continue;
+			}
+
+			break;
+		}
+	}
+
+	list_for_each_entry(orig_table, &table_list, jump_info) {
+		next_table = list_next_entry(orig_table, jump_info);
+		list_for_each_entry_from(next_table, &table_list, jump_info) {
+			if (next_table->rodata_offset < orig_table->rodata_offset) {
+				tmp_insn_offset = next_table->insn_offset;
+				tmp_rodata_offset = next_table->rodata_offset;
+				next_table->insn_offset = orig_table->insn_offset;
+				next_table->rodata_offset = orig_table->rodata_offset;
+				orig_table->insn_offset = tmp_insn_offset;
+				orig_table->rodata_offset = tmp_rodata_offset;
+			}
+		}
+	}
+
+	list_for_each_entry(orig_table, &table_list, jump_info) {
+		if (insn->offset == orig_table->insn_offset) {
+			next_table = list_next_entry(orig_table, jump_info);
+			if (&next_table->jump_info == &table_list) {
+				*table_size = 0;
+				return;
+			}
+
+			while (next_table->rodata_offset == orig_table->rodata_offset) {
+				next_table = list_next_entry(next_table, jump_info);
+				if (&next_table->jump_info == &table_list) {
+					*table_size = 0;
+					return;
+				}
+			}
+
+			*table_size = next_table->rodata_offset - orig_table->rodata_offset;
+		}
+	}
+}
+
+static struct reloc *find_reloc_by_table_annotate(struct objtool_file *file,
+						  struct instruction *insn,
+						  unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+	unsigned long offset;
+
+	rsec = find_section_by_name(file->elf, ".rela.discard.tablejump_annotate");
+	if (!rsec)
+		return NULL;
+
+	for_each_reloc(rsec, reloc) {
+		if (reloc->sym->sec->rodata)
+			continue;
+
+		if (strcmp(insn->sec->name, reloc->sym->sec->name))
+			continue;
+
+		offset = reloc->sym->offset + reloc_addend(reloc);
+		if (insn->offset == offset) {
+			get_rodata_table_size_by_table_annotate(file, insn, table_size);
+			reloc++;
+			return reloc;
+		}
+	}
+
+	return NULL;
+}
+
+static struct reloc *find_reloc_of_rodata_c_jump_table(struct section *sec,
+						       unsigned long offset,
+						       unsigned long *table_size)
+{
+	struct section *rsec;
+	struct reloc *reloc;
+
+	rsec = sec->rsec;
+	if (!rsec)
+		return NULL;
+
+	for_each_reloc(rsec, reloc) {
+		if (reloc_offset(reloc) > offset)
+			break;
+
+		if (!strcmp(reloc->sym->sec->name, C_JUMP_TABLE_SECTION)) {
+			*table_size = 0;
+			return reloc;
+		}
+	}
+
+	return NULL;
+}
+
+struct reloc *arch_find_switch_table(struct objtool_file *file,
+				     struct instruction *insn,
+				     unsigned long *table_size)
+{
+	struct reloc *annotate_reloc;
+	struct reloc *rodata_reloc;
+	struct section *table_sec;
+	unsigned long table_offset;
+
+	annotate_reloc = find_reloc_by_table_annotate(file, insn, table_size);
+	if (!annotate_reloc) {
+		annotate_reloc = find_reloc_of_rodata_c_jump_table(
+				 insn->sec, insn->offset, table_size);
+		if (!annotate_reloc)
+			return NULL;
+	}
+
+	table_sec = annotate_reloc->sym->sec;
+	table_offset = annotate_reloc->sym->offset + reloc_addend(annotate_reloc);
+
+	/*
+	 * Each table entry has a rela associated with it.  The rela
+	 * should reference text in the same function as the original
+	 * instruction.
+	 */
+	rodata_reloc = find_reloc_by_dest(file->elf, table_sec, table_offset);
+	if (!rodata_reloc)
+		return NULL;
+
+	return rodata_reloc;
+}
+
+const char *arch_cpu_feature_name(int feature_number)
+{
+	return NULL;
+}