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-rw-r--r--tools/objtool/arch/loongarch/decode.c356
1 files changed, 356 insertions, 0 deletions
diff --git a/tools/objtool/arch/loongarch/decode.c b/tools/objtool/arch/loongarch/decode.c
new file mode 100644
index 00000000000000..aee479d2191c21
--- /dev/null
+++ b/tools/objtool/arch/loongarch/decode.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#include <string.h>
+#include <objtool/check.h>
+#include <objtool/warn.h>
+#include <asm/inst.h>
+#include <asm/orc_types.h>
+#include <linux/objtool_types.h>
+
+#ifndef EM_LOONGARCH
+#define EM_LOONGARCH 258
+#endif
+
+int arch_ftrace_match(char *name)
+{
+ return !strcmp(name, "_mcount");
+}
+
+unsigned long arch_jump_destination(struct instruction *insn)
+{
+ return insn->offset + (insn->immediate << 2);
+}
+
+unsigned long arch_dest_reloc_offset(int addend)
+{
+ return addend;
+}
+
+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;
+
+ WARN("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 */
+ 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;
+ }
+ }
+ 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;
+}
+
+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 (inst.word == 0)
+ insn->type = INSN_NOP;
+ else if (inst.reg0i15_format.opcode == break_op) {
+ /* break */
+ 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)
+ WARN("invalid NOP size: %d\n", len);
+
+ nop = LOONGARCH_INSN_NOP;
+
+ return (const char *)&nop;
+}
+
+const char *arch_ret_insn(int len)
+{
+ static u32 ret;
+
+ if (len != LOONGARCH_INSN_SIZE)
+ WARN("invalid RET size: %d\n", len);
+
+ 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;
+}
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-11 18:31:19 +0000