Merge pull request #10221 from ejtagle/bugfix-2.0.x

[2.0.x] DUE: Several fixes to the backtracker
This commit is contained in:
Bob-the-Kuhn 2018-03-27 03:26:10 -05:00 committed by GitHub
commit 78df07ac71
Signed by: GitHub
GPG key ID: 4AEE18F83AFDEB23
13 changed files with 3054 additions and 626 deletions

View file

@ -24,7 +24,7 @@
#include "../../inc/MarlinConfig.h"
#include "../../Marlin.h"
#include "backtrace/backtrace.h"
#include "backtrace/unwinder.h"
// Debug monitor that dumps to the Programming port all status when
// an exception or WDT timeout happens - And then resets the board
@ -112,13 +112,79 @@ static void TXDec(uint32_t v) {
} while (p != &nbrs[0]);
}
// Dump a backtrace entry
static void backtrace_dump_fn(int idx, const backtrace_t* bte, void* ctx) {
TX('#'); TXDec(idx); TX(' ');
TX(bte->name); TX('@');TXHex((uint32_t)bte->function); TX('+'); TXDec((uint32_t)bte->address - (uint32_t)bte->function);
TX(" PC:");TXHex((uint32_t)bte->address); TX('\n');
/* Validate address */
static bool validate_addr(uint32_t addr) {
// Address must be in SRAM (0x20070000 - 0x20088000)
if (addr >= 0x20070000 && addr < 0x20088000)
return true;
// Or in FLASH (0x00080000 - 0x00100000)
if (addr >= 0x00080000 && addr < 0x00100000)
return true;
return false;
}
static bool UnwReadW(const uint32_t a, uint32_t *v) {
if (!validate_addr(a))
return false;
*v = *(uint32_t *)a;
return true;
}
static bool UnwReadH(const uint32_t a, uint16_t *v) {
if (!validate_addr(a))
return false;
*v = *(uint16_t *)a;
return true;
}
static bool UnwReadB(const uint32_t a, uint8_t *v) {
if (!validate_addr(a))
return false;
*v = *(uint8_t *)a;
return true;
}
// Dump a backtrace entry
static bool UnwReportOut(void* ctx, const UnwReport* bte) {
int* p = (int*)ctx;
(*p)++;
TX('#'); TXDec(*p); TX(" : ");
TX(bte->name?bte->name:"unknown"); TX('@'); TXHex(bte->function);
TX('+'); TXDec(bte->address - bte->function);
TX(" PC:");TXHex(bte->address); TX('\n');
return true;
}
#if defined(UNW_DEBUG)
void UnwPrintf(const char* format, ...) {
char dest[256];
va_list argptr;
va_start(argptr, format);
vsprintf(dest, format, argptr);
va_end(argptr);
TX(&dest[0]);
}
#endif
/* Table of function pointers for passing to the unwinder */
static const UnwindCallbacks UnwCallbacks = {
UnwReportOut,
UnwReadW,
UnwReadH,
UnwReadB
#if defined(UNW_DEBUG)
,UnwPrintf
#endif
};
/**
* HardFaultHandler_C:
* This is called from the HardFault_HandlerAsm with a pointer the Fault stack
@ -129,24 +195,27 @@ static void backtrace_dump_fn(int idx, const backtrace_t* bte, void* ctx) {
* The function ends with a BKPT instruction to force control back into the debugger
*/
extern "C"
void HardFault_HandlerC(unsigned long *hardfault_args, unsigned long cause) {
void HardFault_HandlerC(unsigned long *sp, unsigned long lr, unsigned long cause) {
static const char* causestr[] = {
"NMI","Hard","Mem","Bus","Usage","Debug","WDT","RSTC"
};
UnwindFrame btf;
// Dump report to the Programming port (interrupts are DISABLED)
TXBegin();
TX("\n\n## Software Fault detected ##\n");
TX("Cause: "); TX(causestr[cause]); TX('\n');
TX("R0 : "); TXHex(((unsigned long)hardfault_args[0])); TX('\n');
TX("R1 : "); TXHex(((unsigned long)hardfault_args[1])); TX('\n');
TX("R2 : "); TXHex(((unsigned long)hardfault_args[2])); TX('\n');
TX("R3 : "); TXHex(((unsigned long)hardfault_args[3])); TX('\n');
TX("R12 : "); TXHex(((unsigned long)hardfault_args[4])); TX('\n');
TX("LR : "); TXHex(((unsigned long)hardfault_args[5])); TX('\n');
TX("PC : "); TXHex(((unsigned long)hardfault_args[6])); TX('\n');
TX("PSR : "); TXHex(((unsigned long)hardfault_args[7])); TX('\n');
TX("R0 : "); TXHex(((unsigned long)sp[0])); TX('\n');
TX("R1 : "); TXHex(((unsigned long)sp[1])); TX('\n');
TX("R2 : "); TXHex(((unsigned long)sp[2])); TX('\n');
TX("R3 : "); TXHex(((unsigned long)sp[3])); TX('\n');
TX("R12 : "); TXHex(((unsigned long)sp[4])); TX('\n');
TX("LR : "); TXHex(((unsigned long)sp[5])); TX('\n');
TX("PC : "); TXHex(((unsigned long)sp[6])); TX('\n');
TX("PSR : "); TXHex(((unsigned long)sp[7])); TX('\n');
// Configurable Fault Status Register
// Consists of MMSR, BFSR and UFSR
@ -169,14 +238,18 @@ void HardFault_HandlerC(unsigned long *hardfault_args, unsigned long cause) {
// Bus Fault Address Register
TX("BFAR : "); TXHex((*((volatile unsigned long *)(0xE000ED38)))); TX('\n');
TX("ExcLR: "); TXHex(lr); TX('\n');
TX("ExcSP: "); TXHex((unsigned long)sp); TX('\n');
btf.sp = ((unsigned long)sp) + 8*4; // The original stack pointer
btf.fp = btf.sp;
btf.lr = ((unsigned long)sp[5]);
btf.pc = ((unsigned long)sp[6]) | 1; // Force Thumb, as CORTEX only support it
// Perform a backtrace
TX("\nBacktrace:\n\n");
backtrace_frame_t btf;
btf.sp = ((unsigned long)hardfault_args[7]);
btf.fp = btf.sp;
btf.lr = ((unsigned long)hardfault_args[5]);
btf.pc = ((unsigned long)hardfault_args[6]);
backtrace_dump(&btf, backtrace_dump_fn, nullptr);
int ctr = 0;
UnwindStart(&btf, &UnwCallbacks, &ctr);
// Disable all NVIC interrupts
NVIC->ICER[0] = 0xFFFFFFFF;
@ -202,7 +275,8 @@ __attribute__((naked)) void NMI_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#0 \n"
" mov r1,lr \n"
" mov r2,#0 \n"
" b HardFault_HandlerC \n"
);
}
@ -213,7 +287,8 @@ __attribute__((naked)) void HardFault_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#1 \n"
" mov r1,lr \n"
" mov r2,#1 \n"
" b HardFault_HandlerC \n"
);
}
@ -224,7 +299,8 @@ __attribute__((naked)) void MemManage_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#2 \n"
" mov r1,lr \n"
" mov r2,#2 \n"
" b HardFault_HandlerC \n"
);
}
@ -235,7 +311,8 @@ __attribute__((naked)) void BusFault_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#3 \n"
" mov r1,lr \n"
" mov r2,#3 \n"
" b HardFault_HandlerC \n"
);
}
@ -246,7 +323,8 @@ __attribute__((naked)) void UsageFault_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#4 \n"
" mov r1,lr \n"
" mov r2,#4 \n"
" b HardFault_HandlerC \n"
);
}
@ -257,18 +335,21 @@ __attribute__((naked)) void DebugMon_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#5 \n"
" mov r1,lr \n"
" mov r2,#5 \n"
" b HardFault_HandlerC \n"
);
}
/* This is NOT an exception, it is an interrupt handler - Nevertheless, the framing is the same */
__attribute__((naked)) void WDT_Handler(void) {
__asm volatile (
" tst lr, #4 \n"
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#6 \n"
" mov r1,lr \n"
" mov r2,#6 \n"
" b HardFault_HandlerC \n"
);
}
@ -279,7 +360,8 @@ __attribute__((naked)) void RSTC_Handler(void) {
" ite eq \n"
" mrseq r0, msp \n"
" mrsne r0, psp \n"
" mov r1,#7 \n"
" mov r1,lr \n"
" mov r2,#7 \n"
" b HardFault_HandlerC \n"
);
}

View file

@ -1,544 +0,0 @@
/*
* Libbacktrace
* Copyright 2015 Stephen Street <stephen@redrocketcomputing.com>
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This library was modified, some bugs fixed, stack address validated
* and adapted to be used in Marlin 3D printer firmware as backtracer
* for exceptions for debugging purposes in 2018 by Eduardo José Tagle.
*/
#ifdef ARDUINO_ARCH_SAM
#include "backtrace.h"
#include <stdint.h>
#include <string.h>
typedef struct unwind_control_block {
uint32_t vrs[16];
const uint32_t *current;
int remaining;
int byte;
} unwind_control_block_t;
typedef struct unwind_index {
uint32_t addr_offset;
uint32_t insn;
} unwind_index_t;
/* These symbols point to the unwind index and should be provide by the linker script */
extern const unwind_index_t __exidx_start[];
extern const unwind_index_t __exidx_end[];
/* This prevents the linking of libgcc unwinder code */
void __aeabi_unwind_cpp_pr0(void) {};
void __aeabi_unwind_cpp_pr1(void) {};
void __aeabi_unwind_cpp_pr2(void) {};
/* These symbols point to the start and end of stack */
extern const int _sstack;
extern const int _estack;
/* These symbols point to the start and end of the code section */
extern const int _sfixed;
extern const int _efixed;
/* These symbols point to the start and end of initialized data (could be SRAM functions!) */
extern const int _srelocate;
extern const int _erelocate;
/* Validate stack pointer (SP): It must be in the stack area */
static inline __attribute__((always_inline)) int validate_sp(const void* sp) {
// SP must point into the allocated stack area
if ((uint32_t)sp >= (uint32_t)&_sstack && (uint32_t)sp <= (uint32_t)&_estack)
return 0;
return -1;
}
/* Validate code pointer (PC): It must be either in TEXT or in SRAM */
static inline __attribute__((always_inline)) int validate_pc(const void* pc) {
// PC must point into the text (CODE) area
if ((uint32_t)pc >= (uint32_t)&_sfixed && (uint32_t)pc <= (uint32_t)&_efixed)
return 0;
// Or into the SRAM function area
if ((uint32_t)pc >= (uint32_t)&_srelocate && (uint32_t)pc <= (uint32_t)&_erelocate)
return 0;
return 0;
}
static inline __attribute__((always_inline)) uint32_t prel31_to_addr(const uint32_t *prel31) {
int32_t offset = (((int32_t)(*prel31)) << 1) >> 1;
return ((uint32_t)prel31 + offset) & 0x7fffffff;
}
static const struct unwind_index *unwind_search_index(const unwind_index_t *start, const unwind_index_t *end, uint32_t ip) {
const struct unwind_index *middle;
/* Perform a binary search of the unwind index */
while (start < end - 1) {
middle = start + ((end - start + 1) >> 1);
if (ip < prel31_to_addr(&middle->addr_offset))
end = middle;
else
start = middle;
}
return start;
}
static const char *unwind_get_function_name(void *address) {
uint32_t flag_word = *(uint32_t *)(address - 4);
if ((flag_word & 0xff000000) == 0xff000000) {
return (const char *)(address - 4 - (flag_word & 0x00ffffff));
}
return "unknown";
}
static int unwind_get_next_byte(unwind_control_block_t *ucb) {
int instruction;
/* Are there more instructions */
if (ucb->remaining == 0)
return -1;
/* Extract the current instruction */
instruction = ((*ucb->current) >> (ucb->byte << 3)) & 0xff;
/* Move the next byte */
--ucb->byte;
if (ucb->byte < 0) {
++ucb->current;
ucb->byte = 3;
}
--ucb->remaining;
return instruction;
}
static int unwind_control_block_init(unwind_control_block_t *ucb, const uint32_t *instructions, const backtrace_frame_t *frame) {
/* Initialize control block */
memset(ucb, 0, sizeof(unwind_control_block_t));
ucb->current = instructions;
/* Is a short unwind description */
if ((*instructions & 0xff000000) == 0x80000000) {
ucb->remaining = 3;
ucb->byte = 2;
/* Is a long unwind description */
} else if ((*instructions & 0xff000000) == 0x81000000) {
ucb->remaining = ((*instructions & 0x00ff0000) >> 14) + 2;
ucb->byte = 1;
} else
return -1;
/* Initialize the virtual register set */
ucb->vrs[7] = frame->fp;
ucb->vrs[13] = frame->sp;
ucb->vrs[14] = frame->lr;
ucb->vrs[15] = 0;
/* All good */
return 0;
}
static int unwind_execute_instruction(unwind_control_block_t *ucb) {
int instruction;
uint32_t mask;
uint32_t reg;
uint32_t *vsp;
/* Consume all instruction byte */
while ((instruction = unwind_get_next_byte(ucb)) != -1) {
if ((instruction & 0xc0) == 0x00) { // ARM_EXIDX_CMD_DATA_POP
/* vsp = vsp + (xxxxxx << 2) + 4 */
ucb->vrs[13] += ((instruction & 0x3f) << 2) + 4;
} else
if ((instruction & 0xc0) == 0x40) { // ARM_EXIDX_CMD_DATA_PUSH
/* vsp = vsp - (xxxxxx << 2) - 4 */
ucb->vrs[13] -= ((instruction & 0x3f) << 2) - 4;
} else
if ((instruction & 0xf0) == 0x80) {
/* pop under mask {r15-r12},{r11-r4} or refuse to unwind */
instruction = instruction << 8 | unwind_get_next_byte(ucb);
/* Check for refuse to unwind */
if (instruction == 0x8000) // ARM_EXIDX_CMD_REFUSED
return 0;
/* Pop registers using mask */ // ARM_EXIDX_CMD_REG_POP
vsp = (uint32_t *)ucb->vrs[13];
mask = instruction & 0xfff;
reg = 4;
while (mask) {
if ((mask & 1) != 0) {
if (validate_sp(vsp))
return -1;
ucb->vrs[reg] = *vsp++;
}
mask >>= 1;
++reg;
}
/* Patch up the vrs sp if it was in the mask */
if ((instruction & (1 << (13 - 4))) != 0)
ucb->vrs[13] = (uint32_t)vsp;
} else
if ((instruction & 0xf0) == 0x90 && // ARM_EXIDX_CMD_REG_TO_SP
instruction != 0x9d &&
instruction != 0x9f) {
/* vsp = r[nnnn] */
ucb->vrs[13] = ucb->vrs[instruction & 0x0f];
} else
if ((instruction & 0xf0) == 0xa0) { // ARM_EXIDX_CMD_REG_POP
/* pop r4-r[4+nnn] or pop r4-r[4+nnn], r14*/
vsp = (uint32_t *)ucb->vrs[13];
for (reg = 4; reg <= (instruction & 0x07) + 4; ++reg) {
if (validate_sp(vsp))
return -1;
ucb->vrs[reg] = *vsp++;
}
if (instruction & 0x08) { // ARM_EXIDX_CMD_REG_POP
if (validate_sp(vsp))
return -1;
ucb->vrs[14] = *vsp++;
}
ucb->vrs[13] = (uint32_t)vsp;
} else
if (instruction == 0xb0) { // ARM_EXIDX_CMD_FINISH
/* finished */
if (ucb->vrs[15] == 0)
ucb->vrs[15] = ucb->vrs[14];
/* All done unwinding */
return 0;
} else
if (instruction == 0xb1) { // ARM_EXIDX_CMD_REG_POP
/* pop register under mask {r3,r2,r1,r0} */
vsp = (uint32_t *)ucb->vrs[13];
mask = unwind_get_next_byte(ucb);
reg = 0;
while (mask) {
if ((mask & 1) != 0) {
if (validate_sp(vsp))
return -1;
ucb->vrs[reg] = *vsp++;
}
mask >>= 1;
++reg;
}
ucb->vrs[13] = (uint32_t)vsp;
} else
if (instruction == 0xb2) { // ARM_EXIDX_CMD_DATA_POP
/* vps = vsp + 0x204 + (uleb128 << 2) */
ucb->vrs[13] += 0x204 + (unwind_get_next_byte(ucb) << 2);
} else
if (instruction == 0xb3 || // ARM_EXIDX_CMD_VFP_POP
instruction == 0xc8 ||
instruction == 0xc9) {
/* pop VFP double-precision registers */
vsp = (uint32_t *)ucb->vrs[13];
/* D[ssss]-D[ssss+cccc] */
if (validate_sp(vsp))
return -1;
ucb->vrs[14] = *vsp++;
if (instruction == 0xc8) {
/* D[16+sssss]-D[16+ssss+cccc] */
ucb->vrs[14] |= 1 << 16;
}
if (instruction != 0xb3) {
/* D[sssss]-D[ssss+cccc] */
ucb->vrs[14] |= 1 << 17;
}
ucb->vrs[13] = (uint32_t)vsp;
} else
if ((instruction & 0xf8) == 0xb8 ||
(instruction & 0xf8) == 0xd0) {
/* Pop VFP double precision registers D[8]-D[8+nnn] */
ucb->vrs[14] = 0x80 | (instruction & 0x07);
if ((instruction & 0xf8) == 0xd0) {
ucb->vrs[14] = 1 << 17;
}
} else
return -1;
}
return instruction != -1;
}
static inline __attribute__((always_inline)) uint32_t *read_psp(void) {
/* Read the current PSP and return its value as a pointer */
uint32_t psp;
__asm volatile (
" mrs %0, psp \n"
: "=r" (psp) : :
);
return (uint32_t*)psp;
}
static int unwind_frame(backtrace_frame_t *frame) {
unwind_control_block_t ucb;
const unwind_index_t *index;
const uint32_t *instructions;
int execution_result;
/* Search the unwind index for the matching unwind table */
index = unwind_search_index(__exidx_start, __exidx_end, frame->pc);
if (index == NULL)
return -1;
/* Make sure we can unwind this frame */
if (index->insn == 0x00000001)
return 0;
/* Get the pointer to the first unwind instruction */
if (index->insn & 0x80000000)
instructions = &index->insn;
else
instructions = (uint32_t *)prel31_to_addr(&index->insn);
/* Initialize the unwind control block */
if (unwind_control_block_init(&ucb, instructions, frame) < 0)
return -1;
/* Execute the unwind instructions */
while ((execution_result = unwind_execute_instruction(&ucb)) > 0);
if (execution_result == -1)
return -1;
/* Set the virtual pc to the virtual lr if this is the first unwind */
if (ucb.vrs[15] == 0)
ucb.vrs[15] = ucb.vrs[14];
/* Check for exception return */
/* TODO Test with other ARM processors to verify this method. */
if ((ucb.vrs[15] & 0xf0000000) == 0xf0000000) {
/* According to the Cortex Programming Manual (p.44), the stack address is always 8-byte aligned (Cortex-M7).
Depending on where the exception came from (MSP or PSP), we need the right SP value to work with.
ucb.vrs[7] contains the right value, so take it and align it by 8 bytes, store it as the current
SP to work with (ucb.vrs[13]) which is then saved as the current (virtual) frame's SP.
*/
uint32_t *stack;
ucb.vrs[13] = (ucb.vrs[7] & ~7);
/* If we need to start from the MSP, we need to go down X words to find the PC, where:
X=2 if it was a non-floating-point exception
X=20 if it was a floating-point (VFP) exception
If we need to start from the PSP, we need to go up exactly 6 words to find the PC.
See the ARMv7-M Architecture Reference Manual p.594 and Cortex-M7 Processor Programming Manual p.44/p.45 for details.
*/
if ((ucb.vrs[15] & 0xc) == 0) {
/* Return to Handler Mode: MSP (0xffffff-1) */
stack = (uint32_t*)(ucb.vrs[13]);
/* The PC is always 2 words down from the MSP, if it was a non-floating-point exception */
stack -= 2;
/* If there was a VFP exception (0xffffffe1), the PC is located another 18 words down */
if ((ucb.vrs[15] & 0xf0) == 0xe0) {
stack -= 18;
}
}
else {
/* Return to Thread Mode: PSP (0xffffff-d) */
stack = read_psp();
/* The PC is always 6 words up from the PSP */
stack += 6;
}
/* Store the PC */
ucb.vrs[15] = *stack--;
/* Store the LR */
ucb.vrs[14] = *stack--;
}
/* We are done if current frame pc is equal to the virtual pc, prevent infinite loop */
if (frame->pc == ucb.vrs[15])
return 0;
/* Update the frame */
frame->fp = ucb.vrs[7];
frame->sp = ucb.vrs[13];
frame->lr = ucb.vrs[14];
frame->pc = ucb.vrs[15];
/* All good */
return 1;
}
// Detect if function names are available
static int __attribute__ ((noinline)) has_function_names(void) {
uint32_t flag_word = ((uint32_t*)&has_function_names)[-1];
return ((flag_word & 0xff000000) == 0xff000000) ? 1 : 0;
}
// Detect if unwind information is present or not
static int has_unwind_info(void) {
return ((char*)(&__exidx_end) - (char*)(&__exidx_start)) > 16 ? 1 : 0; // 16 because there are default entries we can´t supress
}
int backtrace_dump(backtrace_frame_t *frame, backtrace_dump_fn_t dump_entry, void* ctx )
{
backtrace_t entry;
int count = 1;
/* If there is no unwind information, perform a RAW try at it. Idea was taken from
* https://stackoverflow.com/questions/3398664/how-to-get-a-call-stack-backtrace-deeply-embedded-no-library-support
*
* And requires code to be compiled with the following flags:
* -mtpcs-frame -mtpcs-leaf-frame -fno-omit-frame-pointer
* With these options, the Stack pointer is automatically
* pushed to the stack at the beginning of each function.
*/
if (!has_unwind_info()) {
/*
* We basically iterate through the current stack finding the
* following combination of values:
* - <Frame Address>
* - <Link Address>
* This combination will occur for each function in the call stack
*/
uint32_t previous_frame_address = (uint32_t)frame->sp;
uint32_t* stack_pointer = (uint32_t*)frame->sp;
// loop following stack frames
while (1) {
// Validate stack address
if (validate_sp(stack_pointer))
break;
// Attempt to obtain next stack pointer
// The link address should come immediately after
const uint32_t possible_frame_address = *stack_pointer;
const uint32_t possible_link_address = *(stack_pointer+1);
// Next check that the frame addresss (i.e. stack pointer for the function)
// and Link address are within an acceptable range
if(possible_frame_address > previous_frame_address &&
validate_sp((const void *)possible_frame_address) == 0 &&
(possible_link_address & 1) != 0 && // in THUMB mode the address will be odd
validate_pc((const void *)possible_link_address) == 0) {
// We found two acceptable values.
entry.name = "unknown";
entry.address = (void*)possible_link_address;
entry.function = 0;
// If there are function names, try to solve name
if (has_function_names()) {
// Lets find the function name, if possible
// Align address to 4 bytes
uint32_t* pf = (uint32_t*) (((uint32_t)possible_link_address) & (-4));
// Scan backwards until we find the function name
while(validate_pc(pf-1) == 0) {
// Get name descriptor value
uint32_t v = pf[-1];
// Check if name descriptor is valid and name is terminated in 0.
if ((v & 0xffffff00) == 0xff000000 &&
(v & 0xff) > 1) {
// Assume the name was found!
entry.name = ((const char*)pf) - 4 - (v & 0xff);
entry.function = (void*)pf;
break;
}
// Go backwards to the previous word
--pf;
}
}
dump_entry(count, &entry, ctx);
++count;
// Update the book-keeping registers for the next search
previous_frame_address = possible_frame_address;
stack_pointer = (uint32_t*)(possible_frame_address + 4);
} else {
// Keep iterating through the stack until we find an acceptable combination
++stack_pointer;
}
}
} else {
/* Otherwise, unwind information is present. Use it to unwind frames */
do {
if (frame->pc == 0) {
/* Reached __exidx_end. */
entry.name = "<reached end of unwind table>";
entry.address = 0;
entry.function = 0;
dump_entry(count, &entry, ctx);
break;
}
if (frame->pc == 0x00000001) {
/* Reached .cantunwind instruction. */
entry.name = "<reached .cantunwind>";
entry.address = 0;
entry.function = 0;
dump_entry(count, &entry, ctx);
break;
}
/* Find the unwind index of the current frame pc */
const unwind_index_t *index = unwind_search_index(__exidx_start, __exidx_end, frame->pc);
/* Clear last bit (Thumb indicator) */
frame->pc &= 0xfffffffeU;
/* Generate the backtrace information */
entry.address = (void *)frame->pc;
entry.function = (void *)prel31_to_addr(&index->addr_offset);
entry.name = unwind_get_function_name(entry.function);
dump_entry(count, &entry, ctx);
/* Next backtrace frame */
++count;
} while (unwind_frame(frame) == 1);
}
/* All done */
return count;
}
#endif

View file

@ -1,53 +0,0 @@
/*
* Libbacktrace
* Copyright 2015 Stephen Street <stephen@redrocketcomputing.com>
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This library was modified and adapted to be used in Marlin 3D printer
* firmware as backtracer for exceptions for debugging purposes in 2018
* by Eduardo José Tagle.
*/
/*
* For this library to work, you need to compile with the following options
* -funwind-tables => So we will have unwind information to perform the stack trace
* -mpoke-function-name => So we will have function names in the trace
*/
#ifndef _BACKTRACE_H_
#define _BACKTRACE_H_
#include <stdint.h>
#ifdef __cplusplus
extern "C" {
#endif
/* A frame */
typedef struct backtrace_frame {
uint32_t fp;
uint32_t sp;
uint32_t lr;
uint32_t pc;
} backtrace_frame_t;
/* A backtrace */
typedef struct backtrace {
void *function;
void *address;
const char *name;
} backtrace_t;
typedef void (*backtrace_dump_fn_t)(int idx, const backtrace_t* bte, void* ctx);
/* Perform a backtrace, given the specified stack start frame */
int backtrace_dump(backtrace_frame_t *startframe, backtrace_dump_fn_t fn, void* ctx );
#ifdef __cplusplus
}
#endif
#endif // _BACKTRACE_H_

View file

@ -0,0 +1,179 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commercially or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liability for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Utility functions and glue for ARM unwinding sub-modules.
**************************************************************************/
#ifdef ARDUINO_ARCH_SAM
#define MODULE_NAME "UNWARM"
#include <stdint.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdarg.h>
#include <string.h>
#include "unwarm.h"
#include "unwarmmem.h"
#if defined(UNW_DEBUG)
/** Printf wrapper.
* This is used such that alternative outputs for any output can be selected
* by modification of this wrapper function.
*/
void UnwPrintf(const char *format, ...) {
va_list args;
va_start( args, format );
vprintf(format, args );
}
#endif
/** Invalidate all general purpose registers.
*/
void UnwInvalidateRegisterFile(RegData *regFile) {
uint8_t t = 0;
do {
regFile[t].o = REG_VAL_INVALID;
t++;
} while(t < 13);
}
/** Initialise the data used for unwinding.
*/
void UnwInitState(UnwState * const state, /**< Pointer to structure to fill. */
const UnwindCallbacks *cb, /**< Callbacks. */
void *rptData, /**< Data to pass to report function. */
uint32_t pcValue, /**< PC at which to start unwinding. */
uint32_t spValue) { /**< SP at which to start unwinding. */
UnwInvalidateRegisterFile(state->regData);
/* Store the pointer to the callbacks */
state->cb = cb;
state->reportData = rptData;
/* Setup the SP and PC */
state->regData[13].v = spValue;
state->regData[13].o = REG_VAL_FROM_CONST;
state->regData[15].v = pcValue;
state->regData[15].o = REG_VAL_FROM_CONST;
UnwPrintd3("\nInitial: PC=0x%08x SP=0x%08x\n", pcValue, spValue);
/* Invalidate all memory addresses */
memset(state->memData.used, 0, sizeof(state->memData.used));
}
// Detect if function names are available
static int __attribute__ ((noinline)) has_function_names(void) {
uint32_t flag_word = ((uint32_t*)(((uint32_t)(&has_function_names)) & (-4))) [-1];
return ((flag_word & 0xff000000) == 0xff000000) ? 1 : 0;
}
/** Call the report function to indicate some return address.
* This returns the value of the report function, which if true
* indicates that unwinding may continue.
*/
bool UnwReportRetAddr(UnwState * const state, uint32_t addr) {
UnwReport entry;
// We found two acceptable values.
entry.name = NULL;
entry.address = addr & 0xFFFFFFFE; // Remove Thumb bit
entry.function = 0;
// If there are function names, try to solve name
if (has_function_names()) {
// Lets find the function name, if possible
// Align address to 4 bytes
uint32_t pf = addr & (-4);
// Scan backwards until we find the function name
uint32_t v;
while(state->cb->readW(pf-4,&v)) {
// Check if name descriptor is valid
if ((v & 0xffffff00) == 0xff000000 &&
(v & 0xff) > 1) {
// Assume the name was found!
entry.name = ((const char*)pf) - 4 - (v & 0xff);
entry.function = pf;
break;
}
// Go backwards to the previous word
pf -= 4;;
}
}
/* Cast away const from reportData.
* The const is only to prevent the unw module modifying the data.
*/
return state->cb->report((void *)state->reportData, &entry);
}
/** Write some register to memory.
* This will store some register and meta data onto the virtual stack.
* The address for the write
* \param state [in/out] The unwinding state.
* \param wAddr [in] The address at which to write the data.
* \param reg [in] The register to store.
* \return true if the write was successful, false otherwise.
*/
bool UnwMemWriteRegister(UnwState * const state, const uint32_t addr, const RegData * const reg) {
return UnwMemHashWrite(&state->memData, addr, reg->v, M_IsOriginValid(reg->o));
}
/** Read a register from memory.
* This will read a register from memory, and setup the meta data.
* If the register has been previously written to memory using
* UnwMemWriteRegister, the local hash will be used to return the
* value while respecting whether the data was valid or not. If the
* register was previously written and was invalid at that point,
* REG_VAL_INVALID will be returned in *reg.
* \param state [in] The unwinding state.
* \param addr [in] The address to read.
* \param reg [out] The result, containing the data value and the origin
* which will be REG_VAL_FROM_MEMORY, or REG_VAL_INVALID.
* \return true if the address could be read and *reg has been filled in.
* false is the data could not be read.
*/
bool UnwMemReadRegister(UnwState * const state, const uint32_t addr, RegData * const reg) {
bool tracked;
/* Check if the value can be found in the hash */
if(UnwMemHashRead(&state->memData, addr, &reg->v, &tracked)) {
reg->o = tracked ? REG_VAL_FROM_MEMORY : REG_VAL_INVALID;
return true;
}
/* Not in the hash, so read from real memory */
else if(state->cb->readW(addr, &reg->v)) {
reg->o = REG_VAL_FROM_MEMORY;
return true;
}
/* Not in the hash, and failed to read from memory */
else {
return false;
}
}
#endif

View file

@ -0,0 +1,155 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commerically or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liablity for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Internal interface between the ARM unwinding sub-modules.
**************************************************************************/
#ifndef UNWARM_H
#define UNWARM_H
#include "unwinder.h"
/** The maximum number of instructions to interpet in a function.
* Unwinding will be unconditionally stopped and UNWIND_EXHAUSTED returned
* if more than this number of instructions are interpreted in a single
* function without unwinding a stack frame. This prevents infinite loops
* or corrupted program memory from preventing unwinding from progressing.
*/
#define UNW_MAX_INSTR_COUNT 500
/** The size of the hash used to track reads and writes to memory.
* This should be a prime value for efficiency.
*/
#define MEM_HASH_SIZE 31
/***************************************************************************
* Type Definitions
**************************************************************************/
typedef enum {
/** Invalid value. */
REG_VAL_INVALID = 0x00,
REG_VAL_FROM_STACK = 0x01,
REG_VAL_FROM_MEMORY = 0x02,
REG_VAL_FROM_CONST = 0x04,
REG_VAL_ARITHMETIC = 0x80
} RegValOrigin;
/** Type for tracking information about a register.
* This stores the register value, as well as other data that helps unwinding.
*/
typedef struct {
/** The value held in the register. */
uint32_t v;
/** The origin of the register value.
* This is used to track how the value in the register was loaded.
*/
RegValOrigin o;
} RegData;
/** Structure used to track reads and writes to memory.
* This structure is used as a hash to store a small number of writes
* to memory.
*/
typedef struct {
/** Memory contents. */
uint32_t v[MEM_HASH_SIZE];
/** Address at which v[n] represents. */
uint32_t a[MEM_HASH_SIZE];
/** Indicates whether the data in v[n] and a[n] is occupied.
* Each bit represents one hash value.
*/
uint8_t used[(MEM_HASH_SIZE + 7) / 8];
/** Indicates whether the data in v[n] is valid.
* This allows a[n] to be set, but for v[n] to be marked as invalid.
* Specifically this is needed for when an untracked register value
* is written to memory.
*/
uint8_t tracked[(MEM_HASH_SIZE + 7) / 8];
} MemData;
/** Structure that is used to keep track of unwinding meta-data.
* This data is passed between all the unwinding functions.
*/
typedef struct {
/** The register values and meta-data. */
RegData regData[16];
/** Memory tracking data. */
MemData memData;
/** Pointer to the callback functions */
const UnwindCallbacks *cb;
/** Pointer to pass to the report function. */
const void *reportData;
} UnwState;
/***************************************************************************
* Macros
**************************************************************************/
#define M_IsOriginValid(v) (((v) & 0x7f) ? true : false)
#define M_Origin2Str(v) ((v) ? "VALID" : "INVALID")
#if defined(UNW_DEBUG)
#define UnwPrintd1(a) state->cb->printf(a)
#define UnwPrintd2(a,b) state->cb->printf(a,b)
#define UnwPrintd3(a,b,c) state->cb->printf(a,b,c)
#define UnwPrintd4(a,b,c,d) state->cb->printf(a,b,c,d)
#define UnwPrintd5(a,b,c,d,e) state->cb->printf(a,b,c,d,e)
#define UnwPrintd6(a,b,c,d,e,f) state->cb->printf(a,b,c,d,e,f)
#define UnwPrintd7(a,b,c,d,e,f,g) state->cb->printf(a,b,c,d,e,f,g)
#define UnwPrintd8(a,b,c,d,e,f,g,h) state->cb->printf(a,b,c,d,e,f,g,h)
#else
#define UnwPrintd1(a)
#define UnwPrintd2(a,b)
#define UnwPrintd3(a,b,c)
#define UnwPrintd4(a,b,c,d)
#define UnwPrintd5(a,b,c,d,e)
#define UnwPrintd6(a,b,c,d,e,f)
#define UnwPrintd7(a,b,c,d,e,f,g)
#define UnwPrintd8(a,b,c,d,e,f,g,h)
#endif
/***************************************************************************
* Function Prototypes
**************************************************************************/
#ifdef __cplusplus
extern "C" {
#endif
UnwResult UnwStartArm(UnwState * const state);
UnwResult UnwStartThumb(UnwState * const state);
void UnwInvalidateRegisterFile(RegData *regFile);
void UnwInitState(UnwState * const state, const UnwindCallbacks *cb, void *rptData, uint32_t pcValue, uint32_t spValue);
bool UnwReportRetAddr(UnwState * const state, uint32_t addr);
bool UnwMemWriteRegister(UnwState * const state, const uint32_t addr, const RegData * const reg);
bool UnwMemReadRegister(UnwState * const state, const uint32_t addr, RegData * const reg);
void UnwMemHashGC(UnwState * const state);
#ifdef __cplusplus
}
#endif
#endif /* UNWARM_H */
/* END OF FILE */

View file

@ -0,0 +1,597 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commercially or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liability for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Abstract interpreter for ARM mode.
**************************************************************************/
#ifdef ARDUINO_ARCH_SAM
#define MODULE_NAME "UNWARM_ARM"
#include <stdio.h>
#include "unwarm.h"
/** Check if some instruction is a data-processing instruction.
* Decodes the passed instruction, checks if it is a data-processing and
* verifies that the parameters and operation really indicate a data-
* processing instruction. This is needed because some parts of the
* instruction space under this instruction can be extended or represent
* other operations such as MRS, MSR.
*
* \param[in] inst The instruction word.
* \retval true Further decoding of the instruction indicates that this is
* a valid data-processing instruction.
* \retval false This is not a data-processing instruction,
*/
static bool isDataProc(uint32_t instr) {
uint8_t opcode = (instr & 0x01e00000) >> 21;
bool S = (instr & 0x00100000) ? true : false;
if((instr & 0xfc000000) != 0xe0000000) {
return false;
} else
if(!S && opcode >= 8 && opcode <= 11) {
/* TST, TEQ, CMP and CMN all require S to be set */
return false;
} else {
return true;
}
}
UnwResult UnwStartArm(UnwState * const state) {
bool found = false;
uint16_t t = UNW_MAX_INSTR_COUNT;
do {
uint32_t instr;
/* Attempt to read the instruction */
if(!state->cb->readW(state->regData[15].v, &instr)) {
return UNWIND_IREAD_W_FAIL;
}
UnwPrintd4("A %x %x %08x:", state->regData[13].v, state->regData[15].v, instr);
/* Check that the PC is still on Arm alignment */
if(state->regData[15].v & 0x3) {
UnwPrintd1("\nError: PC misalignment\n");
return UNWIND_INCONSISTENT;
}
/* Check that the SP and PC have not been invalidated */
if(!M_IsOriginValid(state->regData[13].o) || !M_IsOriginValid(state->regData[15].o)) {
UnwPrintd1("\nError: PC or SP invalidated\n");
return UNWIND_INCONSISTENT;
}
/* Branch and Exchange (BX)
* This is tested prior to data processing to prevent
* mis-interpretation as an invalid TEQ instruction.
*/
if((instr & 0xfffffff0) == 0xe12fff10) {
uint8_t rn = instr & 0xf;
UnwPrintd4("BX r%d\t ; r%d %s\n", rn, rn, M_Origin2Str(state->regData[rn].o));
if(!M_IsOriginValid(state->regData[rn].o)) {
UnwPrintd1("\nUnwind failure: BX to untracked register\n");
return UNWIND_FAILURE;
}
/* Set the new PC value */
state->regData[15].v = state->regData[rn].v;
/* Check if the return value is from the stack */
if(state->regData[rn].o == REG_VAL_FROM_STACK) {
/* Now have the return address */
UnwPrintd2(" Return PC=%x\n", state->regData[15].v & (~0x1));
/* Report the return address */
if(!UnwReportRetAddr(state, state->regData[rn].v)) {
return UNWIND_TRUNCATED;
}
}
/* Determine the return mode */
if(state->regData[rn].v & 0x1) {
/* Branching to THUMB */
return UnwStartThumb(state);
}
else {
/* Branch to ARM */
/* Account for the auto-increment which isn't needed */
state->regData[15].v -= 4;
}
}
/* Branch */
else if((instr & 0xff000000) == 0xea000000) {
int32_t offset = (instr & 0x00ffffff);
/* Shift value */
offset = offset << 2;
/* Sign extend if needed */
if(offset & 0x02000000) {
offset |= 0xfc000000;
}
UnwPrintd2("B %d\n", offset);
/* Adjust PC */
state->regData[15].v += offset;
/* Account for pre-fetch, where normally the PC is 8 bytes
* ahead of the instruction just executed.
*/
state->regData[15].v += 4;
}
/* MRS */
else if((instr & 0xffbf0fff) == 0xe10f0000) {
#if defined(UNW_DEBUG)
bool R = (instr & 0x00400000) ? true : false;
#endif
uint8_t rd = (instr & 0x0000f000) >> 12;
UnwPrintd4("MRS r%d,%s\t; r%d invalidated", rd, R ? "SPSR" : "CPSR", rd);
/* Status registers untracked */
state->regData[rd].o = REG_VAL_INVALID;
}
/* MSR */
else if((instr & 0xffb0f000) == 0xe120f000) {
#if defined(UNW_DEBUG)
bool R = (instr & 0x00400000) ? true : false;
UnwPrintd2("MSR %s_?, ???", R ? "SPSR" : "CPSR");
#endif
/* Status registers untracked.
* Potentially this could change processor mode and switch
* banked registers r8-r14. Most likely is that r13 (sp) will
* be banked. However, invalidating r13 will stop unwinding
* when potentially this write is being used to disable/enable
* interrupts (a common case). Therefore no invalidation is
* performed.
*/
}
/* Data processing */
else if(isDataProc(instr)) {
bool I = (instr & 0x02000000) ? true : false;
uint8_t opcode = (instr & 0x01e00000) >> 21;
#if defined(UNW_DEBUG)
bool S = (instr & 0x00100000) ? true : false;
#endif
uint8_t rn = (instr & 0x000f0000) >> 16;
uint8_t rd = (instr & 0x0000f000) >> 12;
uint16_t operand2 = (instr & 0x00000fff);
uint32_t op2val;
RegValOrigin op2origin;
switch(opcode) {
case 0: UnwPrintd4("AND%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 1: UnwPrintd4("EOR%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 2: UnwPrintd4("SUB%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 3: UnwPrintd4("RSB%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 4: UnwPrintd4("ADD%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 5: UnwPrintd4("ADC%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 6: UnwPrintd4("SBC%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 7: UnwPrintd4("RSC%s r%d,r%d,", S ? "S" : "", rd, rn); break;
case 8: UnwPrintd3("TST%s r%d,", S ? "S" : "", rn); break;
case 9: UnwPrintd3("TEQ%s r%d,", S ? "S" : "", rn); break;
case 10: UnwPrintd3("CMP%s r%d,", S ? "S" : "", rn); break;
case 11: UnwPrintd3("CMN%s r%d,", S ? "S" : "", rn); break;
case 12: UnwPrintd3("ORR%s r%d,", S ? "S" : "", rn); break;
case 13: UnwPrintd3("MOV%s r%d,", S ? "S" : "", rd); break;
case 14: UnwPrintd4("BIC%s r%d,r%d", S ? "S" : "", rd, rn); break;
case 15: UnwPrintd3("MVN%s r%d,", S ? "S" : "", rd); break;
}
/* Decode operand 2 */
if (I) {
uint8_t shiftDist = (operand2 & 0x0f00) >> 8;
uint8_t shiftConst = (operand2 & 0x00ff);
/* rotate const right by 2 * shiftDist */
shiftDist *= 2;
op2val = (shiftConst >> shiftDist) |
(shiftConst << (32 - shiftDist));
op2origin = REG_VAL_FROM_CONST;
UnwPrintd2("#0x%x", op2val);
}
else {
/* Register and shift */
uint8_t rm = (operand2 & 0x000f);
uint8_t regShift = (operand2 & 0x0010) ? true : false;
uint8_t shiftType = (operand2 & 0x0060) >> 5;
uint32_t shiftDist;
#if defined(UNW_DEBUG)
const char * const shiftMnu[4] = { "LSL", "LSR", "ASR", "ROR" };
#endif
UnwPrintd2("r%d ", rm);
/* Get the shift distance */
if(regShift) {
uint8_t rs = (operand2 & 0x0f00) >> 8;
if(operand2 & 0x00800) {
UnwPrintd1("\nError: Bit should be zero\n");
return UNWIND_ILLEGAL_INSTR;
}
else if(rs == 15) {
UnwPrintd1("\nError: Cannot use R15 with register shift\n");
return UNWIND_ILLEGAL_INSTR;
}
/* Get shift distance */
shiftDist = state->regData[rs].v;
op2origin = state->regData[rs].o;
UnwPrintd7("%s r%d\t; r%d %s r%d %s", shiftMnu[shiftType], rs, rm, M_Origin2Str(state->regData[rm].o), rs, M_Origin2Str(state->regData[rs].o));
}
else {
shiftDist = (operand2 & 0x0f80) >> 7;
op2origin = REG_VAL_FROM_CONST;
if(shiftDist) {
UnwPrintd3("%s #%d", shiftMnu[shiftType], shiftDist);
}
UnwPrintd3("\t; r%d %s", rm, M_Origin2Str(state->regData[rm].o));
}
/* Apply the shift type to the source register */
switch(shiftType) {
case 0: /* logical left */
op2val = state->regData[rm].v << shiftDist;
break;
case 1: /* logical right */
if(!regShift && shiftDist == 0) {
shiftDist = 32;
}
op2val = state->regData[rm].v >> shiftDist;
break;
case 2: /* arithmetic right */
if(!regShift && shiftDist == 0) {
shiftDist = 32;
}
if(state->regData[rm].v & 0x80000000) {
/* Register shifts maybe greater than 32 */
if(shiftDist >= 32) {
op2val = 0xffffffff;
}
else {
op2val = state->regData[rm].v >> shiftDist;
op2val |= 0xffffffff << (32 - shiftDist);
}
}
else {
op2val = state->regData[rm].v >> shiftDist;
}
break;
case 3: /* rotate right */
if(!regShift && shiftDist == 0) {
/* Rotate right with extend.
* This uses the carry bit and so always has an
* untracked result.
*/
op2origin = REG_VAL_INVALID;
op2val = 0;
}
else {
/* Limit shift distance to 0-31 incase of register shift */
shiftDist &= 0x1f;
op2val = (state->regData[rm].v >> shiftDist) |
(state->regData[rm].v << (32 - shiftDist));
}
break;
default:
UnwPrintd2("\nError: Invalid shift type: %d\n", shiftType);
return UNWIND_FAILURE;
}
/* Decide the data origin */
if(M_IsOriginValid(op2origin) &&
M_IsOriginValid(state->regData[rm].o)) {
op2origin = state->regData[rm].o;
op2origin |= REG_VAL_ARITHMETIC;
}
else {
op2origin = REG_VAL_INVALID;
}
}
/* Propagate register validity */
switch(opcode) {
case 0: /* AND: Rd := Op1 AND Op2 */
case 1: /* EOR: Rd := Op1 EOR Op2 */
case 2: /* SUB: Rd:= Op1 - Op2 */
case 3: /* RSB: Rd:= Op2 - Op1 */
case 4: /* ADD: Rd:= Op1 + Op2 */
case 12: /* ORR: Rd:= Op1 OR Op2 */
case 14: /* BIC: Rd:= Op1 AND NOT Op2 */
if(!M_IsOriginValid(state->regData[rn].o) ||
!M_IsOriginValid(op2origin)) {
state->regData[rd].o = REG_VAL_INVALID;
}
else {
state->regData[rd].o = state->regData[rn].o;
state->regData[rd].o |= op2origin;
}
break;
case 5: /* ADC: Rd:= Op1 + Op2 + C */
case 6: /* SBC: Rd:= Op1 - Op2 + C */
case 7: /* RSC: Rd:= Op2 - Op1 + C */
/* CPSR is not tracked */
state->regData[rd].o = REG_VAL_INVALID;
break;
case 8: /* TST: set condition codes on Op1 AND Op2 */
case 9: /* TEQ: set condition codes on Op1 EOR Op2 */
case 10: /* CMP: set condition codes on Op1 - Op2 */
case 11: /* CMN: set condition codes on Op1 + Op2 */
break;
case 13: /* MOV: Rd:= Op2 */
case 15: /* MVN: Rd:= NOT Op2 */
state->regData[rd].o = op2origin;
break;
}
/* Account for pre-fetch by temporarily adjusting PC */
if(rn == 15) {
/* If the shift amount is specified in the instruction,
* the PC will be 8 bytes ahead. If a register is used
* to specify the shift amount the PC will be 12 bytes
* ahead.
*/
if(!I && (operand2 & 0x0010))
state->regData[rn].v += 12;
else
state->regData[rn].v += 8;
}
/* Compute values */
switch(opcode) {
case 0: /* AND: Rd := Op1 AND Op2 */
state->regData[rd].v = state->regData[rn].v & op2val;
break;
case 1: /* EOR: Rd := Op1 EOR Op2 */
state->regData[rd].v = state->regData[rn].v ^ op2val;
break;
case 2: /* SUB: Rd:= Op1 - Op2 */
state->regData[rd].v = state->regData[rn].v - op2val;
break;
case 3: /* RSB: Rd:= Op2 - Op1 */
state->regData[rd].v = op2val - state->regData[rn].v;
break;
case 4: /* ADD: Rd:= Op1 + Op2 */
state->regData[rd].v = state->regData[rn].v + op2val;
break;
case 5: /* ADC: Rd:= Op1 + Op2 + C */
case 6: /* SBC: Rd:= Op1 - Op2 + C */
case 7: /* RSC: Rd:= Op2 - Op1 + C */
case 8: /* TST: set condition codes on Op1 AND Op2 */
case 9: /* TEQ: set condition codes on Op1 EOR Op2 */
case 10: /* CMP: set condition codes on Op1 - Op2 */
case 11: /* CMN: set condition codes on Op1 + Op2 */
UnwPrintd1("\t; ????");
break;
case 12: /* ORR: Rd:= Op1 OR Op2 */
state->regData[rd].v = state->regData[rn].v | op2val;
break;
case 13: /* MOV: Rd:= Op2 */
state->regData[rd].v = op2val;
break;
case 14: /* BIC: Rd:= Op1 AND NOT Op2 */
state->regData[rd].v = state->regData[rn].v & (~op2val);
break;
case 15: /* MVN: Rd:= NOT Op2 */
state->regData[rd].v = ~op2val;
break;
}
/* Remove the prefetch offset from the PC */
if(rd != 15 && rn == 15) {
if(!I && (operand2 & 0x0010))
state->regData[rn].v -= 12;
else
state->regData[rn].v -= 8;
}
}
/* Block Data Transfer
* LDM, STM
*/
else if((instr & 0xfe000000) == 0xe8000000) {
bool P = (instr & 0x01000000) ? true : false;
bool U = (instr & 0x00800000) ? true : false;
bool S = (instr & 0x00400000) ? true : false;
bool W = (instr & 0x00200000) ? true : false;
bool L = (instr & 0x00100000) ? true : false;
uint16_t baseReg = (instr & 0x000f0000) >> 16;
uint16_t regList = (instr & 0x0000ffff);
uint32_t addr = state->regData[baseReg].v;
bool addrValid = M_IsOriginValid(state->regData[baseReg].o);
int8_t r;
#if defined(UNW_DEBUG)
/* Display the instruction */
if(L) {
UnwPrintd6("LDM%c%c r%d%s, {reglist}%s\n", P ? 'E' : 'F', U ? 'D' : 'A', baseReg, W ? "!" : "", S ? "^" : "");
}
else {
UnwPrintd6("STM%c%c r%d%s, {reglist}%s\n", !P ? 'E' : 'F', !U ? 'D' : 'A', baseReg, W ? "!" : "", S ? "^" : "");
}
#endif
/* S indicates that banked registers (untracked) are used, unless
* this is a load including the PC when the S-bit indicates that
* that CPSR is loaded from SPSR (also untracked, but ignored).
*/
if(S && (!L || (regList & (0x01 << 15)) == 0)) {
UnwPrintd1("\nError:S-bit set requiring banked registers\n");
return UNWIND_FAILURE;
}
else if(baseReg == 15) {
UnwPrintd1("\nError: r15 used as base register\n");
return UNWIND_FAILURE;
}
else if(regList == 0) {
UnwPrintd1("\nError: Register list empty\n");
return UNWIND_FAILURE;
}
/* Check if ascending or descending.
* Registers are loaded/stored in order of address.
* i.e. r0 is at the lowest address, r15 at the highest.
*/
r = U ? 0 : 15;
do {
/* Check if the register is to be transferred */
if(regList & (0x01 << r)) {
if(P)
addr += U ? 4 : -4;
if(L) {
if(addrValid) {
if(!UnwMemReadRegister(state, addr, &state->regData[r])) {
return UNWIND_DREAD_W_FAIL;
}
/* Update the origin if read via the stack pointer */
if(M_IsOriginValid(state->regData[r].o) && baseReg == 13) {
state->regData[r].o = REG_VAL_FROM_STACK;
}
UnwPrintd5(" R%d = 0x%08x\t; r%d %s\n",r,state->regData[r].v,r, M_Origin2Str(state->regData[r].o));
}
else {
/* Invalidate the register as the base reg was invalid */
state->regData[r].o = REG_VAL_INVALID;
UnwPrintd2(" R%d = ???\n", r);
}
}
else {
if(addrValid) {
if(!UnwMemWriteRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DWRITE_W_FAIL;
}
}
UnwPrintd2(" R%d = 0x%08x\n", r);
}
if(!P)
addr += U ? 4 : -4;
}
/* Check the next register */
r += U ? 1 : -1;
} while(r >= 0 && r <= 15);
/* Check the writeback bit */
if(W)
state->regData[baseReg].v = addr;
/* Check if the PC was loaded */
if(L && (regList & (0x01 << 15))) {
if(!M_IsOriginValid(state->regData[15].o)) {
/* Return address is not valid */
UnwPrintd1("PC popped with invalid address\n");
return UNWIND_FAILURE;
}
else {
/* Store the return address */
if(!UnwReportRetAddr(state, state->regData[15].v)) {
return UNWIND_TRUNCATED;
}
UnwPrintd2(" Return PC=0x%x", state->regData[15].v);
/* Determine the return mode */
if(state->regData[15].v & 0x1) {
/* Branching to THUMB */
return UnwStartThumb(state);
}
else {
/* Branch to ARM */
/* Account for the auto-increment which isn't needed */
state->regData[15].v -= 4;
}
}
}
}
else {
UnwPrintd1("????");
/* Unknown/undecoded. May alter some register, so invalidate file */
UnwInvalidateRegisterFile(state->regData);
}
UnwPrintd1("\n");
/* Should never hit the reset vector */
if(state->regData[15].v == 0) return UNWIND_RESET;
/* Check next address */
state->regData[15].v += 4;
/* Garbage collect the memory hash (used only for the stack) */
UnwMemHashGC(state);
t--;
if(t == 0)
return UNWIND_EXHAUSTED;
} while(!found);
return UNWIND_UNSUPPORTED;
}
#endif

View file

@ -0,0 +1,1129 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commercially or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liability for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Abstract interpretation for Thumb mode.
**************************************************************************/
#ifdef ARDUINO_ARCH_SAM
#define MODULE_NAME "UNWARM_THUMB"
#include <stdio.h>
#include "unwarm.h"
/** Sign extend an 11 bit value.
* This function simply inspects bit 11 of the input \a value, and if
* set, the top 5 bits are set to give a 2's compliment signed value.
* \param value The value to sign extend.
* \return The signed-11 bit value stored in a 16bit data type.
*/
static int32_t signExtend11(uint16_t value) {
if(value & 0x400) {
value |= 0xfffff800;
}
return value;
}
UnwResult UnwStartThumb(UnwState * const state) {
bool found = false;
uint16_t t = UNW_MAX_INSTR_COUNT;
uint32_t lastJumpAddr = 0; // Last JUMP address, to try to detect infinite loops
bool loopDetected = false; // If a loop was detected
do {
uint16_t instr;
/* Attempt to read the instruction */
if(!state->cb->readH(state->regData[15].v & (~0x1), &instr)) {
return UNWIND_IREAD_H_FAIL;
}
UnwPrintd4("T %x %x %04x:", state->regData[13].v, state->regData[15].v, instr);
/* Check that the PC is still on Thumb alignment */
if(!(state->regData[15].v & 0x1)) {
UnwPrintd1("\nError: PC misalignment\n");
return UNWIND_INCONSISTENT;
}
/* Check that the SP and PC have not been invalidated */
if(!M_IsOriginValid(state->regData[13].o) || !M_IsOriginValid(state->regData[15].o)) {
UnwPrintd1("\nError: PC or SP invalidated\n");
return UNWIND_INCONSISTENT;
}
/*
* Detect 32bit thumb instructions
*/
if ((instr & 0xe000) == 0xe000 && (instr & 0x1800) != 0) {
uint16_t instr2;
/* Check next address */
state->regData[15].v += 2;
/* Attempt to read the 2nd part of the instruction */
if(!state->cb->readH(state->regData[15].v & (~0x1), &instr2)) {
return UNWIND_IREAD_H_FAIL;
}
UnwPrintd3(" %x %04x:", state->regData[15].v, instr2);
/*
* Load/Store multiple: Only interpret
* PUSH and POP
*/
if ((instr & 0xfe6f) == 0xe82d) {
bool L = (instr & 0x10) ? true : false;
uint16_t rList = instr2;
if(L) {
uint8_t r;
/* Load from memory: POP */
UnwPrintd1("POP {Rlist}\n");
/* Load registers from stack */
for(r = 0; r < 16; r++) {
if(rList & (0x1 << r)) {
/* Read the word */
if(!UnwMemReadRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DREAD_W_FAIL;
}
/* Alter the origin to be from the stack if it was valid */
if(M_IsOriginValid(state->regData[r].o)) {
state->regData[r].o = REG_VAL_FROM_STACK;
/* If restoring the PC */
if (r == 15) {
/* The bottom bit should have been set to indicate that
* the caller was from Thumb. This would allow return
* by BX for interworking APCS.
*/
if((state->regData[15].v & 0x1) == 0) {
UnwPrintd2("Warning: Return address not to Thumb: 0x%08x\n", state->regData[15].v);
/* Pop into the PC will not switch mode */
return UNWIND_INCONSISTENT;
}
/* Store the return address */
if(!UnwReportRetAddr(state, state->regData[15].v)) {
return UNWIND_TRUNCATED;
}
/* Now have the return address */
UnwPrintd2(" Return PC=%x\n", state->regData[15].v);
/* Compensate for the auto-increment, which isn't needed here */
state->regData[15].v -= 2;
}
} else {
if (r == 15) {
/* Return address is not valid */
UnwPrintd1("PC popped with invalid address\n");
return UNWIND_FAILURE;
}
}
state->regData[13].v += 4;
UnwPrintd3(" r%d = 0x%08x\n", r, state->regData[r].v);
}
}
}
else {
int8_t r;
/* Store to memory: PUSH */
UnwPrintd1("PUSH {Rlist}");
for(r = 15; r >= 0; r--) {
if(rList & (0x1 << r)) {
UnwPrintd4("\n r%d = 0x%08x\t; %s", r, state->regData[r].v, M_Origin2Str(state->regData[r].o));
state->regData[13].v -= 4;
if(!UnwMemWriteRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DWRITE_W_FAIL;
}
}
}
}
}
/*
* PUSH register
*/
else if (instr == 0xf84d && (instr2 & 0x0fff) == 0x0d04) {
uint8_t r = instr2 >> 12;
/* Store to memory: PUSH */
UnwPrintd2("PUSH {R%d}\n", r);
UnwPrintd4("\n r%d = 0x%08x\t; %s", r, state->regData[r].v, M_Origin2Str(state->regData[r].o));
state->regData[13].v -= 4;
if(!UnwMemWriteRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DWRITE_W_FAIL;
}
}
/*
* POP register
*/
else if (instr == 0xf85d && (instr2 & 0x0fff) == 0x0b04) {
uint8_t r = instr2 >> 12;
/* Load from memory: POP */
UnwPrintd2("POP {R%d}\n", r);
/* Read the word */
if(!UnwMemReadRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DREAD_W_FAIL;
}
/* Alter the origin to be from the stack if it was valid */
if(M_IsOriginValid(state->regData[r].o)) {
state->regData[r].o = REG_VAL_FROM_STACK;
/* If restoring the PC */
if (r == 15) {
/* The bottom bit should have been set to indicate that
* the caller was from Thumb. This would allow return
* by BX for interworking APCS.
*/
if((state->regData[15].v & 0x1) == 0) {
UnwPrintd2("Warning: Return address not to Thumb: 0x%08x\n", state->regData[15].v);
/* Pop into the PC will not switch mode */
return UNWIND_INCONSISTENT;
}
/* Store the return address */
if(!UnwReportRetAddr(state, state->regData[15].v)) {
return UNWIND_TRUNCATED;
}
/* Now have the return address */
UnwPrintd2(" Return PC=%x\n", state->regData[15].v);
/* Compensate for the auto-increment, which isn't needed here */
state->regData[15].v -= 2;
}
} else {
if (r == 15) {
/* Return address is not valid */
UnwPrintd1("PC popped with invalid address\n");
return UNWIND_FAILURE;
}
}
state->regData[13].v += 4;
UnwPrintd3(" r%d = 0x%08x\n", r, state->regData[r].v);
}
/*
* TBB / TBH
*/
else if ((instr & 0xfff0) == 0xe8d0 && (instr2 & 0xffe0) == 0xf000) {
/* We are only interested in
* the forms
* TBB [PC, ...]
* TBH [PC, ..., LSL #1]
* as those are used by the C compiler to implement
* the switch clauses
*/
uint8_t rn = instr & 0xf;
uint8_t rm = instr2 & 0xf;
bool H = (instr2 & 0x10) ? true : false;
UnwPrintd5("TB%c [r%d,r%d%s]\n", H ? 'H' : 'B', rn, rm, H ? ",LSL #1" : "");
// We are only interested if the RN is the PC. Let´s choose the 1st destination
if (rn == 15) {
if (H) {
uint16_t rv;
if(!state->cb->readH((state->regData[15].v & (~1)) + 2, &rv)) {
return UNWIND_DREAD_H_FAIL;
}
state->regData[15].v += rv * 2;
} else {
uint8_t rv;
if(!state->cb->readB((state->regData[15].v & (~1)) + 2, &rv)) {
return UNWIND_DREAD_B_FAIL;
}
state->regData[15].v += rv * 2;
}
}
}
/*
* Unconditional branch
*/
else if ((instr & 0xf800) == 0xf000 && (instr2 & 0xd000) == 0x9000) {
uint32_t v;
uint8_t S = (instr & 0x400) >> 10;
uint16_t imm10 = (instr & 0x3ff);
uint8_t J1 = (instr2 & 0x2000) >> 13;
uint8_t J2 = (instr2 & 0x0800) >> 11;
uint16_t imm11 = (instr2 & 0x7ff);
uint8_t I1 = J1 ^ S ^ 1;
uint8_t I2 = J2 ^ S ^ 1;
uint32_t imm32 = (S << 24) | (I1 << 23) | (I2 << 22) |(imm10 << 12) | (imm11 << 1);
if (S) imm32 |= 0xfe000000;
UnwPrintd2("B %d \n", imm32);
/* Update PC */
state->regData[15].v += imm32;
/* Need to advance by a word to account for pre-fetch.
* Advance by a half word here, allowing the normal address
* advance to account for the other half word.
*/
state->regData[15].v += 2;
/* Compute the jump address */
v = state->regData[15].v + 2;
/* Display PC of next instruction */
UnwPrintd2(" New PC=%x", v);
/* Did we detect an infinite loop ? */
loopDetected = lastJumpAddr == v;
/* Remember the last address we jumped to */
lastJumpAddr = v;
}
/*
* Branch with link
*/
else if ((instr & 0xf800) == 0xf000 && (instr2 & 0xd000) == 0xd000) {
uint8_t S = (instr & 0x400) >> 10;
uint16_t imm10 = (instr & 0x3ff);
uint8_t J1 = (instr2 & 0x2000) >> 13;
uint8_t J2 = (instr2 & 0x0800) >> 11;
uint16_t imm11 = (instr2 & 0x7ff);
uint8_t I1 = J1 ^ S ^ 1;
uint8_t I2 = J2 ^ S ^ 1;
uint32_t imm32 = (S << 24) | (I1 << 23) | (I2 << 22) |(imm10 << 12) | (imm11 << 1);
if (S) imm32 |= 0xfe000000;
UnwPrintd2("BL %d \n", imm32);
/* Never taken, as we are unwinding the stack */
if (0) {
/* Store return address in LR register */
state->regData[14].v = state->regData[15].v + 2;
state->regData[14].o = REG_VAL_FROM_CONST;
/* Update PC */
state->regData[15].v += imm32;
/* Need to advance by a word to account for pre-fetch.
* Advance by a half word here, allowing the normal address
* advance to account for the other half word.
*/
state->regData[15].v += 2;
/* Display PC of next instruction */
UnwPrintd2(" Return PC=%x", state->regData[15].v);
/* Report the return address, including mode bit */
if(!UnwReportRetAddr(state, state->regData[15].v)) {
return UNWIND_TRUNCATED;
}
/* Determine the new mode */
if(state->regData[15].v & 0x1) {
/* Branching to THUMB */
/* Account for the auto-increment which isn't needed */
state->regData[15].v -= 2;
}
else {
/* Branch to ARM */
return UnwStartArm(state);
}
}
}
/*
* Conditional branches. Usually not taken, unless infinite loop is detected
*/
else if ((instr & 0xf800) == 0xf000 && (instr2 & 0xd000) == 0x8000) {
uint8_t S = (instr & 0x400) >> 10;
uint16_t imm6 = (instr & 0x3f);
uint8_t J1 = (instr2 & 0x2000) >> 13;
uint8_t J2 = (instr2 & 0x0800) >> 11;
uint16_t imm11 = (instr2 & 0x7ff);
uint8_t I1 = J1 ^ S ^ 1;
uint8_t I2 = J2 ^ S ^ 1;
uint32_t imm32 = (S << 20) | (I1 << 19) | (I2 << 18) |(imm6 << 12) | (imm11 << 1);
if (S) imm32 |= 0xffe00000;
UnwPrintd2("Bcond %d\n", imm32);
/* Take the jump only if a loop is detected */
if (loopDetected) {
/* Update PC */
state->regData[15].v += imm32;
/* Need to advance by a word to account for pre-fetch.
* Advance by a half word here, allowing the normal address
* advance to account for the other half word.
*/
state->regData[15].v += 2;
/* Display PC of next instruction */
UnwPrintd2(" New PC=%x", state->regData[15].v + 2);
}
}
/*
* PC-relative load
* LDR Rd,[PC, #+/-imm]
*/
else if((instr & 0xff7f) == 0xf85f) {
uint8_t rt = (instr2 & 0xf000) >> 12;
uint8_t imm12 = (instr2 & 0x0fff);
bool A = (instr & 0x80) ? true : false;
uint32_t address;
/* Compute load address, adding a word to account for prefetch */
address = (state->regData[15].v & (~0x3)) + 4;
if (A) address += imm12;
else address -= imm12;
UnwPrintd4("LDR r%d,[PC #%c0x%08x]", rt, A?'+':'-', address);
if(!UnwMemReadRegister(state, address, &state->regData[rt])) {
return UNWIND_DREAD_W_FAIL;
}
}
/*
* LDR immediate.
* We are only interested when destination is PC.
* LDR Rt,[Rn , #n]
*/
else if ((instr & 0xfff0) == 0xf8d0) {
uint8_t rn = (instr & 0xf);
uint8_t rt = (instr2 & 0xf000) >> 12;
uint16_t imm12 = (instr2 & 0xfff);
/* If destination is PC and we don't know the source value, then fail */
if (!M_IsOriginValid(state->regData[rn].o)) {
state->regData[rt].o = state->regData[rn].o;
} else {
uint32_t address = state->regData[rn].v + imm12;
if(!UnwMemReadRegister(state, address, &state->regData[rt])) {
return UNWIND_DREAD_W_FAIL;
}
}
}
/*
* LDR immediate
* We are only interested when destination is PC.
* LDR Rt,[Rn , #-n]
* LDR Rt,[Rn], #+/-n]
* LDR Rt,[Rn, #+/-n]!
*/
else if ((instr & 0xfff0) == 0xf850 && (instr2 & 0x0800) == 0x0800) {
uint8_t rn = (instr & 0xf);
uint8_t rt = (instr2 & 0xf000) >> 12;
uint16_t imm8 = (instr2 & 0xff);
bool P = (instr2 & 0x400) ? true : false;
bool U = (instr2 & 0x200) ? true : false;
bool W = (instr2 & 0x100) ? true : false;
if (!M_IsOriginValid(state->regData[rn].o)) {
state->regData[rt].o = state->regData[rn].o;
} else {
uint32_t offaddress = state->regData[rn].v + imm8;
if (U) offaddress += imm8;
else offaddress -= imm8;
uint32_t address;
if (P) {
address = offaddress;
} else {
address = state->regData[rn].v;
}
if(!UnwMemReadRegister(state, address, &state->regData[rt])) {
return UNWIND_DREAD_W_FAIL;
}
if (W) {
state->regData[rn].v = offaddress;
}
}
}
/*
* LDR (register).
* We are interested in the form
* ldr Rt, [Rn, Rm, lsl #x]
* Where Rt is PC, Rn value is known, Rm is not known or unknown
*/
else if ((instr & 0xfff0) == 0xf850 && (instr2 & 0x0fc0) == 0x0000) {
uint8_t rn = (instr & 0xf);
uint8_t rt = (instr2 & 0xf000) >> 12;
uint8_t rm = (instr2 & 0xf);
uint8_t imm2 = (instr2 & 0x30) >> 4;
if (!M_IsOriginValid(state->regData[rn].o) ||
!M_IsOriginValid(state->regData[rm].o)) {
/* If Rt is PC, and Rn is known, then do an exception and assume
Rm equals 0 => This takes the first case in a switch() */
if (rt == 15 && M_IsOriginValid(state->regData[rn].o)) {
uint32_t address = state->regData[rn].v;
if(!UnwMemReadRegister(state, address, &state->regData[rt])) {
return UNWIND_DREAD_W_FAIL;
}
} else {
/* Propagate unknown value */
state->regData[rt].o = state->regData[rn].o;
}
} else {
uint32_t address = state->regData[rn].v + (state->regData[rm].v << imm2);
if(!UnwMemReadRegister(state, address, &state->regData[rt])) {
return UNWIND_DREAD_W_FAIL;
}
}
}
else {
UnwPrintd1("???? (32)");
/* Unknown/undecoded. May alter some register, so invalidate file */
UnwInvalidateRegisterFile(state->regData);
}
/* End of thumb 32bit code */
}
/* Format 1: Move shifted register
* LSL Rd, Rs, #Offset5
* LSR Rd, Rs, #Offset5
* ASR Rd, Rs, #Offset5
*/
else if((instr & 0xe000) == 0x0000 && (instr & 0x1800) != 0x1800) {
bool signExtend;
uint8_t op = (instr & 0x1800) >> 11;
uint8_t offset5 = (instr & 0x07c0) >> 6;
uint8_t rs = (instr & 0x0038) >> 3;
uint8_t rd = (instr & 0x0007);
switch(op) {
case 0: /* LSL */
UnwPrintd6("LSL r%d, r%d, #%d\t; r%d %s", rd, rs, offset5, rs, M_Origin2Str(state->regData[rs].o));
state->regData[rd].v = state->regData[rs].v << offset5;
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
case 1: /* LSR */
UnwPrintd6("LSR r%d, r%d, #%d\t; r%d %s", rd, rs, offset5, rs, M_Origin2Str(state->regData[rs].o));
state->regData[rd].v = state->regData[rs].v >> offset5;
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
case 2: /* ASR */
UnwPrintd6("ASL r%d, r%d, #%d\t; r%d %s", rd, rs, offset5, rs, M_Origin2Str(state->regData[rs].o));
signExtend = (state->regData[rs].v & 0x8000) ? true : false;
state->regData[rd].v = state->regData[rs].v >> offset5;
if(signExtend) {
state->regData[rd].v |= 0xffffffff << (32 - offset5);
}
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
}
}
/* Format 2: add/subtract
* ADD Rd, Rs, Rn
* ADD Rd, Rs, #Offset3
* SUB Rd, Rs, Rn
* SUB Rd, Rs, #Offset3
*/
else if((instr & 0xf800) == 0x1800) {
bool I = (instr & 0x0400) ? true : false;
bool op = (instr & 0x0200) ? true : false;
uint8_t rn = (instr & 0x01c0) >> 6;
uint8_t rs = (instr & 0x0038) >> 3;
uint8_t rd = (instr & 0x0007);
/* Print decoding */
UnwPrintd6("%s r%d, r%d, %c%d\t;",op ? "SUB" : "ADD",rd, rs,I ? '#' : 'r',rn);
UnwPrintd5("r%d %s, r%d %s",rd, M_Origin2Str(state->regData[rd].o),rs, M_Origin2Str(state->regData[rs].o));
if(!I) {
UnwPrintd3(", r%d %s", rn, M_Origin2Str(state->regData[rn].o));
/* Perform calculation */
if(op) {
state->regData[rd].v = state->regData[rs].v - state->regData[rn].v;
}
else {
state->regData[rd].v = state->regData[rs].v + state->regData[rn].v;
}
/* Propagate the origin */
if(M_IsOriginValid(state->regData[rs].o) &&
M_IsOriginValid(state->regData[rn].o)) {
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
}
else {
state->regData[rd].o = REG_VAL_INVALID;
}
}
else {
/* Perform calculation */
if(op) {
state->regData[rd].v = state->regData[rs].v - rn;
}
else {
state->regData[rd].v = state->regData[rs].v + rn;
}
/* Propagate the origin */
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
}
}
/* Format 3: move/compare/add/subtract immediate
* MOV Rd, #Offset8
* CMP Rd, #Offset8
* ADD Rd, #Offset8
* SUB Rd, #Offset8
*/
else if((instr & 0xe000) == 0x2000) {
uint8_t op = (instr & 0x1800) >> 11;
uint8_t rd = (instr & 0x0700) >> 8;
uint8_t offset8 = (instr & 0x00ff);
switch(op) {
case 0: /* MOV */
UnwPrintd3("MOV r%d, #0x%x", rd, offset8);
state->regData[rd].v = offset8;
state->regData[rd].o = REG_VAL_FROM_CONST;
break;
case 1: /* CMP */
/* Irrelevant to unwinding */
UnwPrintd1("CMP ???");
break;
case 2: /* ADD */
UnwPrintd5("ADD r%d, #0x%x\t; r%d %s", rd, offset8, rd, M_Origin2Str(state->regData[rd].o));
state->regData[rd].v += offset8;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
case 3: /* SUB */
UnwPrintd5("SUB r%d, #0x%d\t; r%d %s", rd, offset8, rd, M_Origin2Str(state->regData[rd].o));
state->regData[rd].v -= offset8;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
}
}
/* Format 4: ALU operations
* AND Rd, Rs
* EOR Rd, Rs
* LSL Rd, Rs
* LSR Rd, Rs
* ASR Rd, Rs
* ADC Rd, Rs
* SBC Rd, Rs
* ROR Rd, Rs
* TST Rd, Rs
* NEG Rd, Rs
* CMP Rd, Rs
* CMN Rd, Rs
* ORR Rd, Rs
* MUL Rd, Rs
* BIC Rd, Rs
* MVN Rd, Rs
*/
else if((instr & 0xfc00) == 0x4000) {
uint8_t op = (instr & 0x03c0) >> 6;
uint8_t rs = (instr & 0x0038) >> 3;
uint8_t rd = (instr & 0x0007);
#if defined(UNW_DEBUG)
static const char * const mnu[16] = {
"AND", "EOR", "LSL", "LSR",
"ASR", "ADC", "SBC", "ROR",
"TST", "NEG", "CMP", "CMN",
"ORR", "MUL", "BIC", "MVN" };
#endif
/* Print the mnemonic and registers */
switch(op) {
case 0: /* AND */
case 1: /* EOR */
case 2: /* LSL */
case 3: /* LSR */
case 4: /* ASR */
case 7: /* ROR */
case 9: /* NEG */
case 12: /* ORR */
case 13: /* MUL */
case 15: /* MVN */
UnwPrintd8("%s r%d ,r%d\t; r%d %s, r%d %s",mnu[op],rd, rs, rd, M_Origin2Str(state->regData[rd].o), rs, M_Origin2Str(state->regData[rs].o));
break;
case 5: /* ADC */
case 6: /* SBC */
UnwPrintd4("%s r%d, r%d", mnu[op], rd, rs);
break;
case 8: /* TST */
case 10: /* CMP */
case 11: /* CMN */
/* Irrelevant to unwinding */
UnwPrintd2("%s ???", mnu[op]);
break;
case 14: /* BIC */
UnwPrintd5("r%d ,r%d\t; r%d %s", rd, rs, rs, M_Origin2Str(state->regData[rs].o));
break;
}
/* Perform operation */
switch(op) {
case 0: /* AND */
state->regData[rd].v &= state->regData[rs].v;
break;
case 1: /* EOR */
state->regData[rd].v ^= state->regData[rs].v;
break;
case 2: /* LSL */
state->regData[rd].v <<= state->regData[rs].v;
break;
case 3: /* LSR */
state->regData[rd].v >>= state->regData[rs].v;
break;
case 4: /* ASR */
if(state->regData[rd].v & 0x80000000) {
state->regData[rd].v >>= state->regData[rs].v;
state->regData[rd].v |= 0xffffffff << (32 - state->regData[rs].v);
}
else {
state->regData[rd].v >>= state->regData[rs].v;
}
break;
case 5: /* ADC */
case 6: /* SBC */
case 8: /* TST */
case 10: /* CMP */
case 11: /* CMN */
break;
case 7: /* ROR */
state->regData[rd].v = (state->regData[rd].v >> state->regData[rs].v) |
(state->regData[rd].v << (32 - state->regData[rs].v));
break;
case 9: /* NEG */
state->regData[rd].v = -state->regData[rs].v;
break;
case 12: /* ORR */
state->regData[rd].v |= state->regData[rs].v;
break;
case 13: /* MUL */
state->regData[rd].v *= state->regData[rs].v;
break;
case 14: /* BIC */
state->regData[rd].v &= ~state->regData[rs].v;
break;
case 15: /* MVN */
state->regData[rd].v = ~state->regData[rs].v;
break;
}
/* Propagate data origins */
switch(op) {
case 0: /* AND */
case 1: /* EOR */
case 2: /* LSL */
case 3: /* LSR */
case 4: /* ASR */
case 7: /* ROR */
case 12: /* ORR */
case 13: /* MUL */
case 14: /* BIC */
if(M_IsOriginValid(state->regData[rd].o) && M_IsOriginValid(state->regData[rs].o)) {
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
}
else {
state->regData[rd].o = REG_VAL_INVALID;
}
break;
case 5: /* ADC */
case 6: /* SBC */
/* C-bit not tracked */
state->regData[rd].o = REG_VAL_INVALID;
break;
case 8: /* TST */
case 10: /* CMP */
case 11: /* CMN */
/* Nothing propagated */
break;
case 9: /* NEG */
case 15: /* MVN */
state->regData[rd].o = state->regData[rs].o;
state->regData[rd].o |= REG_VAL_ARITHMETIC;
break;
}
}
/* Format 5: Hi register operations/branch exchange
* ADD Rd, Hs
* CMP Hd, Rs
* MOV Hd, Hs
*/
else if((instr & 0xfc00) == 0x4400) {
uint8_t op = (instr & 0x0300) >> 8;
bool h1 = (instr & 0x0080) ? true: false;
bool h2 = (instr & 0x0040) ? true: false;
uint8_t rhs = (instr & 0x0038) >> 3;
uint8_t rhd = (instr & 0x0007);
/* Adjust the register numbers */
if(h2)
rhs += 8;
if(h1)
rhd += 8;
switch(op) {
case 0: /* ADD */
UnwPrintd5("ADD r%d, r%d\t; r%d %s", rhd, rhs, rhs, M_Origin2Str(state->regData[rhs].o));
state->regData[rhd].v += state->regData[rhs].v;
state->regData[rhd].o = state->regData[rhs].o;
state->regData[rhd].o |= REG_VAL_ARITHMETIC;
break;
case 1: /* CMP */
/* Irrelevant to unwinding */
UnwPrintd1("CMP ???");
break;
case 2: /* MOV */
UnwPrintd5("MOV r%d, r%d\t; r%d %s", rhd, rhs, rhd, M_Origin2Str(state->regData[rhs].o));
state->regData[rhd].v = state->regData[rhs].v;
state->regData[rhd].o = state->regData[rhd].o;
break;
case 3: /* BX */
UnwPrintd4("BX r%d\t; r%d %s\n", rhs, rhs, M_Origin2Str(state->regData[rhs].o));
/* Only follow BX if the data was from the stack or BX LR */
if(rhs == 14 || state->regData[rhs].o == REG_VAL_FROM_STACK) {
UnwPrintd2(" Return PC=0x%x\n", state->regData[rhs].v & (~0x1));
/* Report the return address, including mode bit */
if(!UnwReportRetAddr(state, state->regData[rhs].v)) {
return UNWIND_TRUNCATED;
}
/* Update the PC */
state->regData[15].v = state->regData[rhs].v;
/* Determine the new mode */
if(state->regData[rhs].v & 0x1) {
/* Branching to THUMB */
/* Account for the auto-increment which isn't needed */
state->regData[15].v -= 2;
}
else {
/* Branch to ARM */
return UnwStartArm(state);
}
}
else {
UnwPrintd4("\nError: BX to invalid register: r%d = 0x%x (%s)\n", rhs, state->regData[rhs].o, M_Origin2Str(state->regData[rhs].o));
return UNWIND_FAILURE;
}
}
}
/* Format 9: PC-relative load
* LDR Rd,[PC, #imm]
*/
else if((instr & 0xf800) == 0x4800) {
uint8_t rd = (instr & 0x0700) >> 8;
uint8_t word8 = (instr & 0x00ff);
uint32_t address;
/* Compute load address, adding a word to account for prefetch */
address = (state->regData[15].v & (~0x3)) + 4 + (word8 << 2);
UnwPrintd3("LDR r%d, 0x%08x", rd, address);
if(!UnwMemReadRegister(state, address, &state->regData[rd])) {
return UNWIND_DREAD_W_FAIL;
}
}
/* Format 13: add offset to Stack Pointer
* ADD sp,#+imm
* ADD sp,#-imm
*/
else if((instr & 0xff00) == 0xB000) {
uint8_t value = (instr & 0x7f) * 4;
/* Check the negative bit */
if((instr & 0x80) != 0) {
UnwPrintd2("SUB sp,#0x%x", value);
state->regData[13].v -= value;
}
else {
UnwPrintd2("ADD sp,#0x%x", value);
state->regData[13].v += value;
}
}
/* Format 14: push/pop registers
* PUSH {Rlist}
* PUSH {Rlist, LR}
* POP {Rlist}
* POP {Rlist, PC}
*/
else if((instr & 0xf600) == 0xb400) {
bool L = (instr & 0x0800) ? true : false;
bool R = (instr & 0x0100) ? true : false;
uint8_t rList = (instr & 0x00ff);
if(L) {
uint8_t r;
/* Load from memory: POP */
UnwPrintd2("POP {Rlist%s}\n", R ? ", PC" : "");
for(r = 0; r < 8; r++) {
if(rList & (0x1 << r)) {
/* Read the word */
if(!UnwMemReadRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DREAD_W_FAIL;
}
/* Alter the origin to be from the stack if it was valid */
if(M_IsOriginValid(state->regData[r].o)) {
state->regData[r].o = REG_VAL_FROM_STACK;
}
state->regData[13].v += 4;
UnwPrintd3(" r%d = 0x%08x\n", r, state->regData[r].v);
}
}
/* Check if the PC is to be popped */
if(R) {
/* Get the return address */
if(!UnwMemReadRegister(state, state->regData[13].v, &state->regData[15])) {
return UNWIND_DREAD_W_FAIL;
}
/* Alter the origin to be from the stack if it was valid */
if(!M_IsOriginValid(state->regData[15].o)) {
/* Return address is not valid */
UnwPrintd1("PC popped with invalid address\n");
return UNWIND_FAILURE;
}
else {
/* The bottom bit should have been set to indicate that
* the caller was from Thumb. This would allow return
* by BX for interworking APCS.
*/
if((state->regData[15].v & 0x1) == 0) {
UnwPrintd2("Warning: Return address not to Thumb: 0x%08x\n", state->regData[15].v);
/* Pop into the PC will not switch mode */
return UNWIND_INCONSISTENT;
}
/* Store the return address */
if(!UnwReportRetAddr(state, state->regData[15].v)) {
return UNWIND_TRUNCATED;
}
/* Now have the return address */
UnwPrintd2(" Return PC=%x\n", state->regData[15].v);
/* Update the pc */
state->regData[13].v += 4;
/* Compensate for the auto-increment, which isn't needed here */
state->regData[15].v -= 2;
}
}
}
else {
int8_t r;
/* Store to memory: PUSH */
UnwPrintd2("PUSH {Rlist%s}", R ? ", LR" : "");
/* Check if the LR is to be pushed */
if(R) {
UnwPrintd3("\n lr = 0x%08x\t; %s", state->regData[14].v, M_Origin2Str(state->regData[14].o));
state->regData[13].v -= 4;
/* Write the register value to memory */
if(!UnwMemWriteRegister(state, state->regData[13].v, &state->regData[14])) {
return UNWIND_DWRITE_W_FAIL;
}
}
for(r = 7; r >= 0; r--) {
if(rList & (0x1 << r)) {
UnwPrintd4("\n r%d = 0x%08x\t; %s", r, state->regData[r].v, M_Origin2Str(state->regData[r].o));
state->regData[13].v -= 4;
if(!UnwMemWriteRegister(state, state->regData[13].v, &state->regData[r])) {
return UNWIND_DWRITE_W_FAIL;
}
}
}
}
}
/*
* Conditional branches
* Bcond
*/
else if((instr & 0xf000) == 0xd000) {
int32_t branchValue = (instr & 0xff);
if (branchValue & 0x80) branchValue |= 0xffffff00;
/* Branch distance is twice that specified in the instruction. */
branchValue *= 2;
UnwPrintd2("Bcond %d \n", branchValue);
/* Only take the branch if a loop was detected */
if (loopDetected) {
/* Update PC */
state->regData[15].v += branchValue;
/* Need to advance by a word to account for pre-fetch.
* Advance by a half word here, allowing the normal address
* advance to account for the other half word.
*/
state->regData[15].v += 2;
/* Display PC of next instruction */
UnwPrintd2(" New PC=%x", state->regData[15].v + 2);
}
}
/* Format 18: unconditional branch
* B label
*/
else if((instr & 0xf800) == 0xe000) {
uint32_t v;
int32_t branchValue = signExtend11(instr & 0x07ff);
/* Branch distance is twice that specified in the instruction. */
branchValue *= 2;
UnwPrintd2("B %d \n", branchValue);
/* Update PC */
state->regData[15].v += branchValue;
/* Need to advance by a word to account for pre-fetch.
* Advance by a half word here, allowing the normal address
* advance to account for the other half word.
*/
state->regData[15].v += 2;
/* Compute the jump address */
v = state->regData[15].v + 2;
/* Display PC of next instruction */
UnwPrintd2(" New PC=%x", v);
/* Did we detect an infinite loop ? */
loopDetected = lastJumpAddr == v;
/* Remember the last address we jumped to */
lastJumpAddr = v;
}
else {
UnwPrintd1("????");
/* Unknown/undecoded. May alter some register, so invalidate file */
UnwInvalidateRegisterFile(state->regData);
}
UnwPrintd1("\n");
/* Should never hit the reset vector */
if(state->regData[15].v == 0)
return UNWIND_RESET;
/* Check next address */
state->regData[15].v += 2;
/* Garbage collect the memory hash (used only for the stack) */
UnwMemHashGC(state);
t--;
if(t == 0)
return UNWIND_EXHAUSTED;
} while(!found);
return UNWIND_SUCCESS;
}
#endif

View file

@ -0,0 +1,443 @@
/*
* Libbacktrace
* Copyright 2015 Stephen Street <stephen@redrocketcomputing.com>
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This library was modified, some bugs fixed, stack address validated
* and adapted to be used in Marlin 3D printer firmware as backtracer
* for exceptions for debugging purposes in 2018 by Eduardo José Tagle.
*/
#ifdef ARDUINO_ARCH_SAM
#include "unwarmbytab.h"
#include <stdint.h>
#include <string.h>
/* These symbols point to the unwind index and should be provide by the linker script */
extern const UnwTabEntry __exidx_start[];
extern const UnwTabEntry __exidx_end[];
/* This prevents the linking of libgcc unwinder code */
void __aeabi_unwind_cpp_pr0(void) {};
void __aeabi_unwind_cpp_pr1(void) {};
void __aeabi_unwind_cpp_pr2(void) {};
static inline __attribute__((always_inline)) uint32_t prel31_to_addr(const uint32_t *prel31) {
uint32_t offset = (((uint32_t)(*prel31)) << 1) >> 1;
return ((uint32_t)prel31 + offset) & 0x7fffffff;
}
static const UnwTabEntry *UnwTabSearchIndex(const UnwTabEntry *start, const UnwTabEntry *end, uint32_t ip) {
const UnwTabEntry *middle;
/* Perform a binary search of the unwind index */
while (start < end - 1) {
middle = start + ((end - start + 1) >> 1);
if (ip < prel31_to_addr(&middle->addr_offset))
end = middle;
else
start = middle;
}
return start;
}
/*
* Get the function name or NULL if not found
*/
static const char *UnwTabGetFunctionName(const UnwindCallbacks *cb, uint32_t address) {
uint32_t flag_word = 0;
if (!cb->readW(address-4,&flag_word))
return NULL;
if ((flag_word & 0xff000000) == 0xff000000) {
return (const char *)(address - 4 - (flag_word & 0x00ffffff));
}
return NULL;
}
/**
* Get the next frame unwinding instruction
*
* Return either the instruction or -1 to signal no more instructions
* are available
*/
static int UnwTabGetNextInstruction(const UnwindCallbacks *cb, UnwTabState *ucb) {
int instruction;
/* Are there more instructions */
if (ucb->remaining == 0)
return -1;
/* Extract the current instruction */
uint32_t v = 0;
if (!cb->readW(ucb->current, &v))
return -1;
instruction = (v >> (ucb->byte << 3)) & 0xff;
/* Move the next byte */
--ucb->byte;
if (ucb->byte < 0) {
ucb->current += 4;
ucb->byte = 3;
}
--ucb->remaining;
return instruction;
}
/**
* Initialize the frame unwinding state
*/
static UnwResult UnwTabStateInit(const UnwindCallbacks *cb, UnwTabState *ucb, uint32_t instructions, const UnwindFrame *frame) {
/* Initialize control block */
memset(ucb, 0, sizeof(UnwTabState));
ucb->current = instructions;
/* Is a short unwind description */
uint32_t v = 0;
if (!cb->readW(instructions, &v))
return UNWIND_DREAD_W_FAIL;
if ((v & 0xff000000) == 0x80000000) {
ucb->remaining = 3;
ucb->byte = 2;
/* Is a long unwind description */
} else if ((v & 0xff000000) == 0x81000000) {
ucb->remaining = ((v & 0x00ff0000) >> 14) + 2;
ucb->byte = 1;
} else
return UNWIND_UNSUPPORTED_DWARF_PERSONALITY;
/* Initialize the virtual register set */
ucb->vrs[7] = frame->fp;
ucb->vrs[13] = frame->sp;
ucb->vrs[14] = frame->lr;
ucb->vrs[15] = 0;
/* All good */
return UNWIND_SUCCESS;
}
/*
* Execute unwinding instructions
*/
static UnwResult UnwTabExecuteInstructions(const UnwindCallbacks *cb, UnwTabState *ucb) {
UnwResult err;
int instruction;
uint32_t mask;
uint32_t reg;
uint32_t vsp;
/* Consume all instruction byte */
while ((instruction = UnwTabGetNextInstruction(cb, ucb)) != -1) {
if ((instruction & 0xc0) == 0x00) { // ARM_EXIDX_CMD_DATA_POP
/* vsp = vsp + (xxxxxx << 2) + 4 */
ucb->vrs[13] += ((instruction & 0x3f) << 2) + 4;
} else
if ((instruction & 0xc0) == 0x40) { // ARM_EXIDX_CMD_DATA_PUSH
/* vsp = vsp - (xxxxxx << 2) - 4 */
ucb->vrs[13] -= ((instruction & 0x3f) << 2) - 4;
} else
if ((instruction & 0xf0) == 0x80) {
/* pop under mask {r15-r12},{r11-r4} or refuse to unwind */
instruction = instruction << 8 | UnwTabGetNextInstruction(cb, ucb);
/* Check for refuse to unwind */
if (instruction == 0x8000) // ARM_EXIDX_CMD_REFUSED
return UNWIND_REFUSED;
/* Pop registers using mask */ // ARM_EXIDX_CMD_REG_POP
vsp = ucb->vrs[13];
mask = instruction & 0xfff;
reg = 4;
while (mask) {
if ((mask & 1) != 0) {
uint32_t v;
if (!cb->readW(vsp,&v))
return UNWIND_DREAD_W_FAIL;
ucb->vrs[reg] = v;
v += 4;
}
mask >>= 1;
++reg;
}
/* Patch up the vrs sp if it was in the mask */
if ((instruction & (1 << (13 - 4))) != 0)
ucb->vrs[13] = vsp;
} else
if ((instruction & 0xf0) == 0x90 && // ARM_EXIDX_CMD_REG_TO_SP
instruction != 0x9d &&
instruction != 0x9f) {
/* vsp = r[nnnn] */
ucb->vrs[13] = ucb->vrs[instruction & 0x0f];
} else
if ((instruction & 0xf0) == 0xa0) { // ARM_EXIDX_CMD_REG_POP
/* pop r4-r[4+nnn] or pop r4-r[4+nnn], r14*/
vsp = ucb->vrs[13];
for (reg = 4; reg <= (instruction & 0x07) + 4; ++reg) {
uint32_t v;
if (!cb->readW(vsp,&v))
return UNWIND_DREAD_W_FAIL;
ucb->vrs[reg] = v;
vsp += 4;
}
if (instruction & 0x08) { // ARM_EXIDX_CMD_REG_POP
uint32_t v;
if (!cb->readW(vsp,&v))
return UNWIND_DREAD_W_FAIL;
ucb->vrs[14] = v;
vsp += 4;
}
ucb->vrs[13] = vsp;
} else
if (instruction == 0xb0) { // ARM_EXIDX_CMD_FINISH
/* finished */
if (ucb->vrs[15] == 0)
ucb->vrs[15] = ucb->vrs[14];
/* All done unwinding */
return UNWIND_SUCCESS;
} else
if (instruction == 0xb1) { // ARM_EXIDX_CMD_REG_POP
/* pop register under mask {r3,r2,r1,r0} */
vsp = ucb->vrs[13];
mask = UnwTabGetNextInstruction(cb, ucb);
reg = 0;
while (mask) {
if ((mask & 1) != 0) {
uint32_t v;
if (!cb->readW(vsp,&v))
return UNWIND_DREAD_W_FAIL;
ucb->vrs[reg] = v;
vsp += 4;
}
mask >>= 1;
++reg;
}
ucb->vrs[13] = (uint32_t)vsp;
} else
if (instruction == 0xb2) { // ARM_EXIDX_CMD_DATA_POP
/* vps = vsp + 0x204 + (uleb128 << 2) */
ucb->vrs[13] += 0x204 + (UnwTabGetNextInstruction(cb, ucb) << 2);
} else
if (instruction == 0xb3 || // ARM_EXIDX_CMD_VFP_POP
instruction == 0xc8 ||
instruction == 0xc9) {
/* pop VFP double-precision registers */
vsp = ucb->vrs[13];
/* D[ssss]-D[ssss+cccc] */
uint32_t v;
if (!cb->readW(vsp,&v))
return UNWIND_DREAD_W_FAIL;
ucb->vrs[14] = v;
vsp += 4;
if (instruction == 0xc8) {
/* D[16+sssss]-D[16+ssss+cccc] */
ucb->vrs[14] |= 1 << 16;
}
if (instruction != 0xb3) {
/* D[sssss]-D[ssss+cccc] */
ucb->vrs[14] |= 1 << 17;
}
ucb->vrs[13] = vsp;
} else
if ((instruction & 0xf8) == 0xb8 ||
(instruction & 0xf8) == 0xd0) {
/* Pop VFP double precision registers D[8]-D[8+nnn] */
ucb->vrs[14] = 0x80 | (instruction & 0x07);
if ((instruction & 0xf8) == 0xd0) {
ucb->vrs[14] = 1 << 17;
}
} else
return UNWIND_UNSUPPORTED_DWARF_INSTR;
}
return UNWIND_SUCCESS;
}
static inline __attribute__((always_inline)) uint32_t read_psp(void) {
/* Read the current PSP and return its value as a pointer */
uint32_t psp;
__asm volatile (
" mrs %0, psp \n"
: "=r" (psp) : :
);
return psp;
}
/*
* Unwind the specified frame and goto the previous one
*/
static UnwResult UnwTabUnwindFrame(const UnwindCallbacks *cb, UnwindFrame *frame) {
UnwResult err;
UnwTabState ucb;
const UnwTabEntry *index;
uint32_t instructions;
/* Search the unwind index for the matching unwind table */
index = UnwTabSearchIndex(__exidx_start, __exidx_end, frame->pc);
/* Make sure we can unwind this frame */
if (index->insn == 0x00000001)
return UNWIND_SUCCESS;
/* Get the pointer to the first unwind instruction */
if (index->insn & 0x80000000)
instructions = (uint32_t)&index->insn;
else
instructions = prel31_to_addr(&index->insn);
/* Initialize the unwind control block */
if ((err = UnwTabStateInit(cb, &ucb, instructions, frame)) < 0)
return err;
/* Execute the unwind instructions */
err = UnwTabExecuteInstructions(cb, &ucb);
if (err < 0)
return err;
/* Set the virtual pc to the virtual lr if this is the first unwind */
if (ucb.vrs[15] == 0)
ucb.vrs[15] = ucb.vrs[14];
/* Check for exception return */
/* TODO Test with other ARM processors to verify this method. */
if ((ucb.vrs[15] & 0xf0000000) == 0xf0000000) {
/* According to the Cortex Programming Manual (p.44), the stack address is always 8-byte aligned (Cortex-M7).
Depending on where the exception came from (MSP or PSP), we need the right SP value to work with.
ucb.vrs[7] contains the right value, so take it and align it by 8 bytes, store it as the current
SP to work with (ucb.vrs[13]) which is then saved as the current (virtual) frame's SP.
*/
uint32_t stack;
ucb.vrs[13] = (ucb.vrs[7] & ~7);
/* If we need to start from the MSP, we need to go down X words to find the PC, where:
X=2 if it was a non-floating-point exception
X=20 if it was a floating-point (VFP) exception
If we need to start from the PSP, we need to go up exactly 6 words to find the PC.
See the ARMv7-M Architecture Reference Manual p.594 and Cortex-M7 Processor Programming Manual p.44/p.45 for details.
*/
if ((ucb.vrs[15] & 0xc) == 0) {
/* Return to Handler Mode: MSP (0xffffff-1) */
stack = ucb.vrs[13];
/* The PC is always 2 words down from the MSP, if it was a non-floating-point exception */
stack -= 2*4;
/* If there was a VFP exception (0xffffffe1), the PC is located another 18 words down */
if ((ucb.vrs[15] & 0xf0) == 0xe0) {
stack -= 18*4;
}
}
else {
/* Return to Thread Mode: PSP (0xffffff-d) */
stack = read_psp();
/* The PC is always 6 words up from the PSP */
stack += 6*4;
}
/* Store the PC */
uint32_t v;
if (!cb->readW(stack,&v))
return UNWIND_DREAD_W_FAIL;
ucb.vrs[15] = v;
stack -= 4;
/* Store the LR */
if (!cb->readW(stack,&v))
return UNWIND_DREAD_W_FAIL;
ucb.vrs[14] = v;
stack -= 4;
}
/* We are done if current frame pc is equal to the virtual pc, prevent infinite loop */
if (frame->pc == ucb.vrs[15])
return UNWIND_SUCCESS;
/* Update the frame */
frame->fp = ucb.vrs[7];
frame->sp = ucb.vrs[13];
frame->lr = ucb.vrs[14];
frame->pc = ucb.vrs[15];
/* All good - Continue unwinding */
return UNWIND_MORE_AVAILABLE;
}
UnwResult UnwindByTableStart(UnwindFrame* frame, const UnwindCallbacks *cb, void *data) {
UnwResult err = UNWIND_SUCCESS;
UnwReport entry;
/* Use DWARF unwind information to unwind frames */
do {
if (frame->pc == 0) {
/* Reached __exidx_end. */
break;
}
if (frame->pc == 0x00000001) {
/* Reached .cantunwind instruction. */
break;
}
/* Find the unwind index of the current frame pc */
const UnwTabEntry *index = UnwTabSearchIndex(__exidx_start, __exidx_end, frame->pc);
/* Clear last bit (Thumb indicator) */
frame->pc &= 0xfffffffeU;
/* Generate the backtrace information */
entry.address = frame->pc;
entry.function = prel31_to_addr(&index->addr_offset);
entry.name = UnwTabGetFunctionName(cb, entry.function);
if (!cb->report(data,&entry))
break;
/* Unwind frame and repeat */
} while ((err = UnwTabUnwindFrame(cb, frame)) == UNWIND_MORE_AVAILABLE);
/* All done */
return err;
}
#endif

View file

@ -0,0 +1,44 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commerically or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liablity for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Interface to the memory tracking sub-system.
**************************************************************************/
#ifndef UNWARMBYTAB_H
#define UNWARMBYTAB_H
#include "unwarm.h"
typedef struct {
uint32_t vrs[16];
uint32_t current; /* Address of current byte */
int remaining;
int byte;
} UnwTabState;
typedef struct {
uint32_t addr_offset;
uint32_t insn;
} UnwTabEntry;
#ifdef __cplusplus
extern "C" {
#endif
UnwResult UnwindByTableStart(UnwindFrame* frame, const UnwindCallbacks *cb, void *data);
#ifdef __cplusplus
}
#endif
#endif
/* END OF FILE */

View file

@ -0,0 +1,118 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commerically or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liablity for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Implementation of the memory tracking sub-system.
**************************************************************************/
#ifdef ARDUINO_ARCH_SAM
#define MODULE_NAME "UNWARMMEM"
#include <stdio.h>
#include "unwarmmem.h"
#include "unwarm.h"
#define M_IsIdxUsed(a, v) (((a)[v >> 3] & (1 << (v & 0x7))) ? true : false)
#define M_SetIdxUsed(a, v) ((a)[v >> 3] |= (1 << (v & 0x7)))
#define M_ClrIdxUsed(a, v) ((a)[v >> 3] &= ~(1 << (v & 0x7)))
/** Search the memory hash to see if an entry is stored in the hash already.
* This will search the hash and either return the index where the item is
* stored, or -1 if the item was not found.
*/
static int16_t memHashIndex(MemData * const memData, const uint32_t addr) {
const uint16_t v = addr % MEM_HASH_SIZE;
uint16_t s = v;
do {
/* Check if the element is occupied */
if(M_IsIdxUsed(memData->used, s)) {
/* Check if it is occupied with the sought data */
if(memData->a[s] == addr) {
return s;
}
}
else {
/* Item is free, this is where the item should be stored */
return s;
}
/* Search the next entry */
s++;
if(s > MEM_HASH_SIZE) {
s = 0;
}
} while(s != v);
/* Search failed, hash is full and the address not stored */
return -1;
}
bool UnwMemHashRead(MemData * const memData, uint32_t addr,uint32_t * const data, bool * const tracked) {
int16_t i = memHashIndex(memData, addr);
if(i >= 0 && M_IsIdxUsed(memData->used, i) && memData->a[i] == addr) {
*data = memData->v[i];
*tracked = M_IsIdxUsed(memData->tracked, i);
return true;
}
else {
/* Address not found in the hash */
return false;
}
}
bool UnwMemHashWrite(MemData * const memData, uint32_t addr, uint32_t val, bool valValid) {
int16_t i = memHashIndex(memData, addr);
if(i < 0){
/* Hash full */
return false;
}
else {
/* Store the item */
memData->a[i] = addr;
M_SetIdxUsed(memData->used, i);
if(valValid)
{
memData->v[i] = val;
M_SetIdxUsed(memData->tracked, i);
}
else {
#if defined(UNW_DEBUG)
memData->v[i] = 0xdeadbeef;
#endif
M_ClrIdxUsed(memData->tracked, i);
}
return true;
}
}
void UnwMemHashGC(UnwState * const state) {
const uint32_t minValidAddr = state->regData[13].v;
MemData * const memData = &state->memData;
uint16_t t;
for(t = 0; t < MEM_HASH_SIZE; t++) {
if(M_IsIdxUsed(memData->used, t) && (memData->a[t] < minValidAddr)) {
UnwPrintd3("MemHashGC: Free elem %d, addr 0x%08x\n", t, memData->a[t]);
M_ClrIdxUsed(memData->used, t);
}
}
}
#endif

View file

@ -0,0 +1,33 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commerically or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liablity for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Interface to the memory tracking sub-system.
**************************************************************************/
#ifndef UNWARMMEM_H
#define UNWARMMEM_H
#include "unwarm.h"
#ifdef __cplusplus
extern "C" {
#endif
bool UnwMemHashRead(MemData * const memData, uint32_t addr, uint32_t * const data, bool * const tracked);
bool UnwMemHashWrite(MemData * const memData, uint32_t addr, uint32_t val, bool valValid);
void UnwMemHashGC(UnwState * const state);
#ifdef __cplusplus
}
#endif
#endif

View file

@ -0,0 +1,61 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commercially or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liability for it's use or misuse - this software is without warranty.
***************************************************************************
* File Description: Implementation of the interface into the ARM unwinder.
**************************************************************************/
#ifdef ARDUINO_ARCH_SAM
#define MODULE_NAME "UNWINDER"
#include <stdio.h>
#include <string.h>
#include "unwinder.h"
#include "unwarm.h"
#include "unwarmbytab.h"
/* These symbols point to the unwind index and should be provide by the linker script */
extern const UnwTabEntry __exidx_start[];
extern const UnwTabEntry __exidx_end[];
// Detect if unwind information is present or not
static int HasUnwindTableInfo(void) {
// > 16 because there are default entries we can´t supress
return ((char*)(&__exidx_end) - (char*)(&__exidx_start)) > 16 ? 1 : 0;
}
UnwResult UnwindStart(UnwindFrame* frame, const UnwindCallbacks *cb, void *data) {
if (HasUnwindTableInfo()) {
/* We have unwind information tables */
return UnwindByTableStart(frame, cb, data);
} else {
/* We don't have unwind information tables */
UnwState state;
/* Initialise the unwinding state */
UnwInitState(&state, cb, data, frame->pc, frame->sp);
/* Check the Thumb bit */
if(frame->pc & 0x1) {
return UnwStartThumb(&state);
}
else {
return UnwStartArm(&state);
}
}
}
#endif

View file

@ -0,0 +1,184 @@
/***************************************************************************
* ARM Stack Unwinder, Michael.McTernan.2001@cs.bris.ac.uk
* Updated, adapted and several bug fixes on 2018 by Eduardo José Tagle
*
* This program is PUBLIC DOMAIN.
* This means that there is no copyright and anyone is able to take a copy
* for free and use it as they wish, with or without modifications, and in
* any context, commerically or otherwise. The only limitation is that I
* don't guarantee that the software is fit for any purpose or accept any
* liablity for it's use or misuse - this software is without warranty.
**************************************************************************/
/** \file
* Interface to the ARM stack unwinding module.
**************************************************************************/
#ifndef UNWINDER_H
#define UNWINDER_H
#include <stdint.h>
#include <stdbool.h>
/** \def UNW_DEBUG
* If this define is set, additional information will be produced while
* unwinding the stack to allow debug of the unwind module itself.
*/
/* #define UNW_DEBUG 1 */
/***************************************************************************
* Type Definitions
**************************************************************************/
/** Possible results for UnwindStart to return.
*/
typedef enum {
/** Unwinding was successful and complete. */
UNWIND_SUCCESS = 0,
/** Not an error: More frames are available. */
UNWIND_MORE_AVAILABLE = 1,
/** Unsupported DWARF unwind personality. */
UNWIND_UNSUPPORTED_DWARF_PERSONALITY = -1,
/** Refused to perform unwind. */
UNWIND_REFUSED = -2,
/** Reached an invalid SP. */
UNWIND_INVALID_SP = -3,
/** Reached an invalid PC */
UNWIND_INVALID_PC = -4,
/** Unsupported DWARF instruction */
UNWIND_UNSUPPORTED_DWARF_INSTR = -5,
/** More than UNW_MAX_INSTR_COUNT instructions were interpreted. */
UNWIND_EXHAUSTED = -6,
/** Unwinding stopped because the reporting func returned false. */
UNWIND_TRUNCATED = -7,
/** Read data was found to be inconsistent. */
UNWIND_INCONSISTENT = -8,
/** Unsupported instruction or data found. */
UNWIND_UNSUPPORTED = -9,
/** General failure. */
UNWIND_FAILURE = -10,
/** Illegal instruction. */
UNWIND_ILLEGAL_INSTR = -11,
/** Unwinding hit the reset vector. */
UNWIND_RESET = -12,
/** Failed read for an instruction word. */
UNWIND_IREAD_W_FAIL = -13,
/** Failed read for an instruction half-word. */
UNWIND_IREAD_H_FAIL = -14,
/** Failed read for an instruction byte. */
UNWIND_IREAD_B_FAIL = -15,
/** Failed read for a data word. */
UNWIND_DREAD_W_FAIL = -16,
/** Failed read for a data half-word. */
UNWIND_DREAD_H_FAIL = -17,
/** Failed read for a data byte. */
UNWIND_DREAD_B_FAIL = -18,
/** Failed write for a data word. */
UNWIND_DWRITE_W_FAIL = -19
} UnwResult;
/** A backtrace report */
typedef struct {
uint32_t function; /** Starts address of function */
const char *name; /** Function name, or null if not available */
uint32_t address; /** PC on that function */
} UnwReport;
/** Type for function pointer for result callback.
* The function is passed two parameters, the first is a void * pointer,
* and the second is the return address of the function. The bottom bit
* of the passed address indicates the execution mode; if it is set,
* the execution mode at the return address is Thumb, otherwise it is
* ARM.
*
* The return value of this function determines whether unwinding should
* continue or not. If true is returned, unwinding will continue and the
* report function maybe called again in future. If false is returned,
* unwinding will stop with UnwindStart() returning UNWIND_TRUNCATED.
*/
typedef bool (*UnwindReportFunc)(void* data, const UnwReport* bte);
/** Structure that holds memory callback function pointers.
*/
typedef struct {
/** Report an unwind result. */
UnwindReportFunc report;
/** Read a 32 bit word from memory.
* The memory address to be read is passed as \a address, and
* \a *val is expected to be populated with the read value.
* If the address cannot or should not be read, false can be
* returned to indicate that unwinding should stop. If true
* is returned, \a *val is assumed to be valid and unwinding
* will continue.
*/
bool (*readW)(const uint32_t address, uint32_t *val);
/** Read a 16 bit half-word from memory.
* This function has the same usage as for readW, but is expected
* to read only a 16 bit value.
*/
bool (*readH)(const uint32_t address, uint16_t *val);
/** Read a byte from memory.
* This function has the same usage as for readW, but is expected
* to read only an 8 bit value.
*/
bool (*readB)(const uint32_t address, uint8_t *val);
#if defined(UNW_DEBUG)
/** Print a formatted line for debug. */
void (*printf)(const char *format, ...);
#endif
} UnwindCallbacks;
/* A frame */
typedef struct {
uint32_t fp;
uint32_t sp;
uint32_t lr;
uint32_t pc;
} UnwindFrame;
#ifdef __cplusplus
extern "C" {
#endif
/** Start unwinding the current stack.
* This will unwind the stack starting at the PC value supplied to in the
* link register (i.e. not a normal register) and the stack pointer value
* supplied.
*
* -If the program was compiled with -funwind-tables , it will use them to
* perform the traceback. Otherwise, brute force will be employed
* -If the program was compiled with -mpoke-function-name, then you will
* get function names in the traceback. Otherwise, you will not.
*/
UnwResult UnwindStart(UnwindFrame* frame, const UnwindCallbacks *cb, void *data);
#ifdef __cplusplus
}
#endif
#endif /* UNWINDER_H */