Pull the ARM ddb unwind code out to a new file. This will allow it to be
used by other places that expect to unwind the stack, e.g. dtrace and stack(9). As I have written most of this code I'm changing the license to the standard FreeBSD license. I have received approval from the other developers who have changed any of the affected code. Approved by: ian, imp, rpaulo, eadler (all license change)
This commit is contained in:
parent
8a8f7d5bad
commit
6da235a325
sys
@ -38,6 +38,7 @@ __FBSDID("$FreeBSD$");
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#include <sys/proc.h>
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#include <sys/kdb.h>
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#include <sys/stack.h>
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#include <machine/armreg.h>
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#include <machine/asm.h>
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#include <machine/cpufunc.h>
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@ -45,322 +46,15 @@ __FBSDID("$FreeBSD$");
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#include <machine/pcb.h>
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#include <machine/stack.h>
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#include <machine/vmparam.h>
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#include <ddb/ddb.h>
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#include <ddb/db_access.h>
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#include <ddb/db_sym.h>
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#include <ddb/db_output.h>
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/*
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* Definitions for the instruction interpreter.
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*
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* The ARM EABI specifies how to perform the frame unwinding in the
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* Exception Handling ABI for the ARM Architecture document. To perform
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* the unwind we need to know the initial frame pointer, stack pointer,
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* link register and program counter. We then find the entry within the
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* index table that points to the function the program counter is within.
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* This gives us either a list of three instructions to process, a 31-bit
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* relative offset to a table of instructions, or a value telling us
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* we can't unwind any further.
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*
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* When we have the instructions to process we need to decode them
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* following table 4 in section 9.3. This describes a collection of bit
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* patterns to encode that steps to take to update the stack pointer and
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* link register to the correct values at the start of the function.
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*/
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/* A special case when we are unable to unwind past this function */
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#define EXIDX_CANTUNWIND 1
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/* The register names */
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#define FP 11
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#define SP 13
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#define LR 14
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#define PC 15
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/*
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* These are set in the linker script. Their addresses will be
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* either the start or end of the exception table or index.
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*/
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extern int extab_start, extab_end, exidx_start, exidx_end;
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/*
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* Entry types.
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* These are the only entry types that have been seen in the kernel.
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*/
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#define ENTRY_MASK 0xff000000
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#define ENTRY_ARM_SU16 0x80000000
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#define ENTRY_ARM_LU16 0x81000000
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/* Instruction masks. */
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#define INSN_VSP_MASK 0xc0
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#define INSN_VSP_SIZE_MASK 0x3f
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#define INSN_STD_MASK 0xf0
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#define INSN_STD_DATA_MASK 0x0f
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#define INSN_POP_TYPE_MASK 0x08
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#define INSN_POP_COUNT_MASK 0x07
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#define INSN_VSP_LARGE_INC_MASK 0xff
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/* Instruction definitions */
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#define INSN_VSP_INC 0x00
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#define INSN_VSP_DEC 0x40
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#define INSN_POP_MASKED 0x80
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#define INSN_VSP_REG 0x90
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#define INSN_POP_COUNT 0xa0
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#define INSN_FINISH 0xb0
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#define INSN_POP_REGS 0xb1
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#define INSN_VSP_LARGE_INC 0xb2
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/* An item in the exception index table */
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struct unwind_idx {
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uint32_t offset;
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uint32_t insn;
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};
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/* The state of the unwind process */
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struct unwind_state {
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uint32_t registers[16];
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uint32_t start_pc;
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uint32_t *insn;
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u_int entries;
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u_int byte;
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uint16_t update_mask;
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};
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/* Expand a 31-bit signed value to a 32-bit signed value */
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static __inline int32_t
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db_expand_prel31(uint32_t prel31)
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{
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return ((int32_t)(prel31 & 0x7fffffffu) << 1) / 2;
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}
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/*
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* Perform a binary search of the index table to find the function
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* with the largest address that doesn't exceed addr.
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*/
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static struct unwind_idx *
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db_find_index(uint32_t addr)
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{
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unsigned int min, mid, max;
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struct unwind_idx *start;
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struct unwind_idx *item;
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int32_t prel31_addr;
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uint32_t func_addr;
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start = (struct unwind_idx *)&exidx_start;
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min = 0;
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max = (&exidx_end - &exidx_start) / 2;
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while (min != max) {
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mid = min + (max - min + 1) / 2;
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item = &start[mid];
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prel31_addr = db_expand_prel31(item->offset);
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func_addr = (uint32_t)&item->offset + prel31_addr;
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if (func_addr <= addr) {
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min = mid;
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} else {
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max = mid - 1;
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}
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}
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return &start[min];
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}
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/* Reads the next byte from the instruction list */
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static uint8_t
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db_unwind_exec_read_byte(struct unwind_state *state)
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{
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uint8_t insn;
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/* Read the unwind instruction */
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insn = (*state->insn) >> (state->byte * 8);
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/* Update the location of the next instruction */
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if (state->byte == 0) {
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state->byte = 3;
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state->insn++;
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state->entries--;
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} else
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state->byte--;
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return insn;
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}
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/* Executes the next instruction on the list */
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static int
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db_unwind_exec_insn(struct unwind_state *state)
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{
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unsigned int insn;
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uint32_t *vsp = (uint32_t *)state->registers[SP];
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int update_vsp = 0;
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/* This should never happen */
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if (state->entries == 0)
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return 1;
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/* Read the next instruction */
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insn = db_unwind_exec_read_byte(state);
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if ((insn & INSN_VSP_MASK) == INSN_VSP_INC) {
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state->registers[SP] += ((insn & INSN_VSP_SIZE_MASK) << 2) + 4;
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} else if ((insn & INSN_VSP_MASK) == INSN_VSP_DEC) {
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state->registers[SP] -= ((insn & INSN_VSP_SIZE_MASK) << 2) + 4;
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} else if ((insn & INSN_STD_MASK) == INSN_POP_MASKED) {
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unsigned int mask, reg;
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/* Load the mask */
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mask = db_unwind_exec_read_byte(state);
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mask |= (insn & INSN_STD_DATA_MASK) << 8;
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/* We have a refuse to unwind instruction */
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if (mask == 0)
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return 1;
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/* Update SP */
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update_vsp = 1;
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/* Load the registers */
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for (reg = 4; mask && reg < 16; mask >>= 1, reg++) {
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if (mask & 1) {
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state->registers[reg] = *vsp++;
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state->update_mask |= 1 << reg;
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/* If we have updated SP kep its value */
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if (reg == SP)
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update_vsp = 0;
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}
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}
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} else if ((insn & INSN_STD_MASK) == INSN_VSP_REG &&
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((insn & INSN_STD_DATA_MASK) != 13) &&
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((insn & INSN_STD_DATA_MASK) != 15)) {
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/* sp = register */
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state->registers[SP] =
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state->registers[insn & INSN_STD_DATA_MASK];
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} else if ((insn & INSN_STD_MASK) == INSN_POP_COUNT) {
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unsigned int count, reg;
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/* Read how many registers to load */
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count = insn & INSN_POP_COUNT_MASK;
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/* Update sp */
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update_vsp = 1;
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/* Pop the registers */
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for (reg = 4; reg <= 4 + count; reg++) {
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state->registers[reg] = *vsp++;
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state->update_mask |= 1 << reg;
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}
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/* Check if we are in the pop r14 version */
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if ((insn & INSN_POP_TYPE_MASK) != 0) {
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state->registers[14] = *vsp++;
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}
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} else if (insn == INSN_FINISH) {
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/* Stop processing */
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state->entries = 0;
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} else if (insn == INSN_POP_REGS) {
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unsigned int mask, reg;
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mask = db_unwind_exec_read_byte(state);
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if (mask == 0 || (mask & 0xf0) != 0)
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return 1;
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/* Update SP */
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update_vsp = 1;
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/* Load the registers */
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for (reg = 0; mask && reg < 4; mask >>= 1, reg++) {
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if (mask & 1) {
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state->registers[reg] = *vsp++;
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state->update_mask |= 1 << reg;
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}
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}
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} else if ((insn & INSN_VSP_LARGE_INC_MASK) == INSN_VSP_LARGE_INC) {
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unsigned int uleb128;
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/* Read the increment value */
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uleb128 = db_unwind_exec_read_byte(state);
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state->registers[SP] += 0x204 + (uleb128 << 2);
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} else {
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/* We hit a new instruction that needs to be implemented */
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db_printf("Unhandled instruction %.2x\n", insn);
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return 1;
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}
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if (update_vsp) {
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state->registers[SP] = (uint32_t)vsp;
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}
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#if 0
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db_printf("fp = %08x, sp = %08x, lr = %08x, pc = %08x\n",
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state->registers[FP], state->registers[SP], state->registers[LR],
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state->registers[PC]);
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#endif
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return 0;
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}
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/* Performs the unwind of a function */
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static int
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db_unwind_tab(struct unwind_state *state)
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{
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uint32_t entry;
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/* Set PC to a known value */
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state->registers[PC] = 0;
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/* Read the personality */
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entry = *state->insn & ENTRY_MASK;
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if (entry == ENTRY_ARM_SU16) {
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state->byte = 2;
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state->entries = 1;
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} else if (entry == ENTRY_ARM_LU16) {
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state->byte = 1;
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state->entries = ((*state->insn >> 16) & 0xFF) + 1;
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} else {
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db_printf("Unknown entry: %x\n", entry);
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return 1;
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}
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while (state->entries > 0) {
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if (db_unwind_exec_insn(state) != 0)
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return 1;
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}
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/*
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* The program counter was not updated, load it from the link register.
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*/
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if (state->registers[PC] == 0) {
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state->registers[PC] = state->registers[LR];
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/*
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* If the program counter changed, flag it in the update mask.
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*/
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if (state->start_pc != state->registers[PC])
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state->update_mask |= 1 << PC;
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}
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return 0;
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}
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static void
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db_stack_trace_cmd(struct unwind_state *state)
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{
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struct unwind_idx *index;
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const char *name;
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db_expr_t value;
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db_expr_t offset;
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@ -372,28 +66,7 @@ db_stack_trace_cmd(struct unwind_state *state)
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finished = false;
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while (!finished) {
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/* Reset the mask of updated registers */
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state->update_mask = 0;
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/* The pc value is correct and will be overwritten, save it */
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state->start_pc = state->registers[PC];
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/* Find the item to run */
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index = db_find_index(state->start_pc);
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if (index->insn != EXIDX_CANTUNWIND) {
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if (index->insn & (1U << 31)) {
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/* The data is within the instruction */
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state->insn = &index->insn;
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} else {
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/* A prel31 offset to the unwind table */
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state->insn = (uint32_t *)
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((uintptr_t)&index->insn +
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db_expand_prel31(index->insn));
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}
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/* Run the unwind function */
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finished = db_unwind_tab(state);
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}
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finished = unwind_stack_one(state);
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/* Print the frame details */
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sym = db_search_symbol(state->start_pc, DB_STGY_ANY, &offset);
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@ -432,6 +105,9 @@ db_stack_trace_cmd(struct unwind_state *state)
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}
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db_printf("\n");
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if (finished)
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break;
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/*
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* Stop if directed to do so, or if we've unwound back to the
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* kernel entry point, or if the unwind function didn't change
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@ -441,9 +117,7 @@ db_stack_trace_cmd(struct unwind_state *state)
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* the last frame printed before you see the unwind failure
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* message (maybe it needs a STOP_UNWINDING).
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*/
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if (index->insn == EXIDX_CANTUNWIND) {
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finished = true;
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} else if (state->registers[PC] < VM_MIN_KERNEL_ADDRESS) {
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if (state->registers[PC] < VM_MIN_KERNEL_ADDRESS) {
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db_printf("Unable to unwind into user mode\n");
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finished = true;
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} else if (state->update_mask == 0) {
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369
sys/arm/arm/unwind.c
Normal file
369
sys/arm/arm/unwind.c
Normal file
@ -0,0 +1,369 @@
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/*
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* Copyright 2013-2014 Andrew Turner.
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* Copyright 2013-2014 Ian Lepore.
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* Copyright 2013-2014 Rui Paulo.
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* Copyright 2013 Eitan Adler.
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are
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* met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE
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* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
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* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
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* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
|
||||
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
|
||||
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
|
||||
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <machine/stack.h>
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/*
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* Definitions for the instruction interpreter.
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*
|
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* The ARM EABI specifies how to perform the frame unwinding in the
|
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* Exception Handling ABI for the ARM Architecture document. To perform
|
||||
* the unwind we need to know the initial frame pointer, stack pointer,
|
||||
* link register and program counter. We then find the entry within the
|
||||
* index table that points to the function the program counter is within.
|
||||
* This gives us either a list of three instructions to process, a 31-bit
|
||||
* relative offset to a table of instructions, or a value telling us
|
||||
* we can't unwind any further.
|
||||
*
|
||||
* When we have the instructions to process we need to decode them
|
||||
* following table 4 in section 9.3. This describes a collection of bit
|
||||
* patterns to encode that steps to take to update the stack pointer and
|
||||
* link register to the correct values at the start of the function.
|
||||
*/
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||||
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/* A special case when we are unable to unwind past this function */
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#define EXIDX_CANTUNWIND 1
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/*
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* These are set in the linker script. Their addresses will be
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* either the start or end of the exception table or index.
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||||
*/
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extern int extab_start, extab_end, exidx_start, exidx_end;
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/*
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* Entry types.
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* These are the only entry types that have been seen in the kernel.
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||||
*/
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#define ENTRY_MASK 0xff000000
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#define ENTRY_ARM_SU16 0x80000000
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#define ENTRY_ARM_LU16 0x81000000
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/* Instruction masks. */
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#define INSN_VSP_MASK 0xc0
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#define INSN_VSP_SIZE_MASK 0x3f
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#define INSN_STD_MASK 0xf0
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#define INSN_STD_DATA_MASK 0x0f
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#define INSN_POP_TYPE_MASK 0x08
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#define INSN_POP_COUNT_MASK 0x07
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#define INSN_VSP_LARGE_INC_MASK 0xff
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/* Instruction definitions */
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#define INSN_VSP_INC 0x00
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#define INSN_VSP_DEC 0x40
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#define INSN_POP_MASKED 0x80
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#define INSN_VSP_REG 0x90
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#define INSN_POP_COUNT 0xa0
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#define INSN_FINISH 0xb0
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#define INSN_POP_REGS 0xb1
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#define INSN_VSP_LARGE_INC 0xb2
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/* An item in the exception index table */
|
||||
struct unwind_idx {
|
||||
uint32_t offset;
|
||||
uint32_t insn;
|
||||
};
|
||||
|
||||
/* Expand a 31-bit signed value to a 32-bit signed value */
|
||||
static __inline int32_t
|
||||
expand_prel31(uint32_t prel31)
|
||||
{
|
||||
|
||||
return ((int32_t)(prel31 & 0x7fffffffu) << 1) / 2;
|
||||
}
|
||||
|
||||
/*
|
||||
* Perform a binary search of the index table to find the function
|
||||
* with the largest address that doesn't exceed addr.
|
||||
*/
|
||||
static struct unwind_idx *
|
||||
find_index(uint32_t addr)
|
||||
{
|
||||
unsigned int min, mid, max;
|
||||
struct unwind_idx *start;
|
||||
struct unwind_idx *item;
|
||||
int32_t prel31_addr;
|
||||
uint32_t func_addr;
|
||||
|
||||
start = (struct unwind_idx *)&exidx_start;
|
||||
|
||||
min = 0;
|
||||
max = (&exidx_end - &exidx_start) / 2;
|
||||
|
||||
while (min != max) {
|
||||
mid = min + (max - min + 1) / 2;
|
||||
|
||||
item = &start[mid];
|
||||
|
||||
prel31_addr = expand_prel31(item->offset);
|
||||
func_addr = (uint32_t)&item->offset + prel31_addr;
|
||||
|
||||
if (func_addr <= addr) {
|
||||
min = mid;
|
||||
} else {
|
||||
max = mid - 1;
|
||||
}
|
||||
}
|
||||
|
||||
return &start[min];
|
||||
}
|
||||
|
||||
/* Reads the next byte from the instruction list */
|
||||
static uint8_t
|
||||
unwind_exec_read_byte(struct unwind_state *state)
|
||||
{
|
||||
uint8_t insn;
|
||||
|
||||
/* Read the unwind instruction */
|
||||
insn = (*state->insn) >> (state->byte * 8);
|
||||
|
||||
/* Update the location of the next instruction */
|
||||
if (state->byte == 0) {
|
||||
state->byte = 3;
|
||||
state->insn++;
|
||||
state->entries--;
|
||||
} else
|
||||
state->byte--;
|
||||
|
||||
return insn;
|
||||
}
|
||||
|
||||
/* Executes the next instruction on the list */
|
||||
static int
|
||||
unwind_exec_insn(struct unwind_state *state)
|
||||
{
|
||||
unsigned int insn;
|
||||
uint32_t *vsp = (uint32_t *)state->registers[SP];
|
||||
int update_vsp = 0;
|
||||
|
||||
/* This should never happen */
|
||||
if (state->entries == 0)
|
||||
return 1;
|
||||
|
||||
/* Read the next instruction */
|
||||
insn = unwind_exec_read_byte(state);
|
||||
|
||||
if ((insn & INSN_VSP_MASK) == INSN_VSP_INC) {
|
||||
state->registers[SP] += ((insn & INSN_VSP_SIZE_MASK) << 2) + 4;
|
||||
|
||||
} else if ((insn & INSN_VSP_MASK) == INSN_VSP_DEC) {
|
||||
state->registers[SP] -= ((insn & INSN_VSP_SIZE_MASK) << 2) + 4;
|
||||
|
||||
} else if ((insn & INSN_STD_MASK) == INSN_POP_MASKED) {
|
||||
unsigned int mask, reg;
|
||||
|
||||
/* Load the mask */
|
||||
mask = unwind_exec_read_byte(state);
|
||||
mask |= (insn & INSN_STD_DATA_MASK) << 8;
|
||||
|
||||
/* We have a refuse to unwind instruction */
|
||||
if (mask == 0)
|
||||
return 1;
|
||||
|
||||
/* Update SP */
|
||||
update_vsp = 1;
|
||||
|
||||
/* Load the registers */
|
||||
for (reg = 4; mask && reg < 16; mask >>= 1, reg++) {
|
||||
if (mask & 1) {
|
||||
state->registers[reg] = *vsp++;
|
||||
state->update_mask |= 1 << reg;
|
||||
|
||||
/* If we have updated SP kep its value */
|
||||
if (reg == SP)
|
||||
update_vsp = 0;
|
||||
}
|
||||
}
|
||||
|
||||
} else if ((insn & INSN_STD_MASK) == INSN_VSP_REG &&
|
||||
((insn & INSN_STD_DATA_MASK) != 13) &&
|
||||
((insn & INSN_STD_DATA_MASK) != 15)) {
|
||||
/* sp = register */
|
||||
state->registers[SP] =
|
||||
state->registers[insn & INSN_STD_DATA_MASK];
|
||||
|
||||
} else if ((insn & INSN_STD_MASK) == INSN_POP_COUNT) {
|
||||
unsigned int count, reg;
|
||||
|
||||
/* Read how many registers to load */
|
||||
count = insn & INSN_POP_COUNT_MASK;
|
||||
|
||||
/* Update sp */
|
||||
update_vsp = 1;
|
||||
|
||||
/* Pop the registers */
|
||||
for (reg = 4; reg <= 4 + count; reg++) {
|
||||
state->registers[reg] = *vsp++;
|
||||
state->update_mask |= 1 << reg;
|
||||
}
|
||||
|
||||
/* Check if we are in the pop r14 version */
|
||||
if ((insn & INSN_POP_TYPE_MASK) != 0) {
|
||||
state->registers[14] = *vsp++;
|
||||
}
|
||||
|
||||
} else if (insn == INSN_FINISH) {
|
||||
/* Stop processing */
|
||||
state->entries = 0;
|
||||
|
||||
} else if (insn == INSN_POP_REGS) {
|
||||
unsigned int mask, reg;
|
||||
|
||||
mask = unwind_exec_read_byte(state);
|
||||
if (mask == 0 || (mask & 0xf0) != 0)
|
||||
return 1;
|
||||
|
||||
/* Update SP */
|
||||
update_vsp = 1;
|
||||
|
||||
/* Load the registers */
|
||||
for (reg = 0; mask && reg < 4; mask >>= 1, reg++) {
|
||||
if (mask & 1) {
|
||||
state->registers[reg] = *vsp++;
|
||||
state->update_mask |= 1 << reg;
|
||||
}
|
||||
}
|
||||
|
||||
} else if ((insn & INSN_VSP_LARGE_INC_MASK) == INSN_VSP_LARGE_INC) {
|
||||
unsigned int uleb128;
|
||||
|
||||
/* Read the increment value */
|
||||
uleb128 = unwind_exec_read_byte(state);
|
||||
|
||||
state->registers[SP] += 0x204 + (uleb128 << 2);
|
||||
|
||||
} else {
|
||||
/* We hit a new instruction that needs to be implemented */
|
||||
#if 0
|
||||
db_printf("Unhandled instruction %.2x\n", insn);
|
||||
#endif
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (update_vsp) {
|
||||
state->registers[SP] = (uint32_t)vsp;
|
||||
}
|
||||
|
||||
#if 0
|
||||
db_printf("fp = %08x, sp = %08x, lr = %08x, pc = %08x\n",
|
||||
state->registers[FP], state->registers[SP], state->registers[LR],
|
||||
state->registers[PC]);
|
||||
#endif
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* Performs the unwind of a function */
|
||||
static int
|
||||
unwind_tab(struct unwind_state *state)
|
||||
{
|
||||
uint32_t entry;
|
||||
|
||||
/* Set PC to a known value */
|
||||
state->registers[PC] = 0;
|
||||
|
||||
/* Read the personality */
|
||||
entry = *state->insn & ENTRY_MASK;
|
||||
|
||||
if (entry == ENTRY_ARM_SU16) {
|
||||
state->byte = 2;
|
||||
state->entries = 1;
|
||||
} else if (entry == ENTRY_ARM_LU16) {
|
||||
state->byte = 1;
|
||||
state->entries = ((*state->insn >> 16) & 0xFF) + 1;
|
||||
} else {
|
||||
#if 0
|
||||
db_printf("Unknown entry: %x\n", entry);
|
||||
#endif
|
||||
return 1;
|
||||
}
|
||||
|
||||
while (state->entries > 0) {
|
||||
if (unwind_exec_insn(state) != 0)
|
||||
return 1;
|
||||
}
|
||||
|
||||
/*
|
||||
* The program counter was not updated, load it from the link register.
|
||||
*/
|
||||
if (state->registers[PC] == 0) {
|
||||
state->registers[PC] = state->registers[LR];
|
||||
|
||||
/*
|
||||
* If the program counter changed, flag it in the update mask.
|
||||
*/
|
||||
if (state->start_pc != state->registers[PC])
|
||||
state->update_mask |= 1 << PC;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
int
|
||||
unwind_stack_one(struct unwind_state *state)
|
||||
{
|
||||
struct unwind_idx *index;
|
||||
int finished;
|
||||
|
||||
/* Reset the mask of updated registers */
|
||||
state->update_mask = 0;
|
||||
|
||||
/* The pc value is correct and will be overwritten, save it */
|
||||
state->start_pc = state->registers[PC];
|
||||
|
||||
/* Find the item to run */
|
||||
index = find_index(state->start_pc);
|
||||
|
||||
finished = 0;
|
||||
if (index->insn != EXIDX_CANTUNWIND) {
|
||||
if (index->insn & (1U << 31)) {
|
||||
/* The data is within the instruction */
|
||||
state->insn = &index->insn;
|
||||
} else {
|
||||
/* A prel31 offset to the unwind table */
|
||||
state->insn = (uint32_t *)
|
||||
((uintptr_t)&index->insn +
|
||||
expand_prel31(index->insn));
|
||||
}
|
||||
/* Run the unwind function */
|
||||
finished = unwind_tab(state);
|
||||
}
|
||||
|
||||
/* This is the top of the stack, finish */
|
||||
if (index->insn == EXIDX_CANTUNWIND)
|
||||
finished = 1;
|
||||
|
||||
return (finished);
|
||||
}
|
@ -39,4 +39,22 @@
|
||||
#define FR_RSP (-2)
|
||||
#define FR_RFP (-3)
|
||||
|
||||
/* The state of the unwind process */
|
||||
struct unwind_state {
|
||||
uint32_t registers[16];
|
||||
uint32_t start_pc;
|
||||
uint32_t *insn;
|
||||
u_int entries;
|
||||
u_int byte;
|
||||
uint16_t update_mask;
|
||||
};
|
||||
|
||||
/* The register names */
|
||||
#define FP 11
|
||||
#define SP 13
|
||||
#define LR 14
|
||||
#define PC 15
|
||||
|
||||
int unwind_stack_one(struct unwind_state *);
|
||||
|
||||
#endif /* !_MACHINE_STACK_H_ */
|
||||
|
@ -57,6 +57,7 @@ arm/arm/trap.c optional !armv6
|
||||
arm/arm/trap-v6.c optional armv6
|
||||
arm/arm/uio_machdep.c standard
|
||||
arm/arm/undefined.c standard
|
||||
arm/arm/unwind.c optional ddb
|
||||
arm/arm/vm_machdep.c standard
|
||||
arm/arm/vfp.c standard
|
||||
board_id.h standard \
|
||||
|
Loading…
x
Reference in New Issue
Block a user