Several fixes to the backtracer. Tested ant it works

This commit is contained in:
etagle 2018-03-26 03:42:54 -03:00
parent 9a24c0ae3f
commit 328edea03a
5 changed files with 444 additions and 105 deletions

View File

@ -34,19 +34,6 @@
// Serial interrupt routines or any C runtime, as we don't know the
// state we are when running them
/* These symbols point to the start and end of stack */
extern "C" const int _sstack;
extern "C" const int _estack;
/* These symbols point to the start and end of the code section */
extern "C" const int _sfixed;
extern "C" const int _efixed;
/* These symbols point to the start and end of initialized data (could be SRAM functions!) */
extern "C" const int _srelocate;
extern "C" const int _erelocate;
// A SW memory barrier, to ensure GCC does not overoptimize loops
#define sw_barrier() asm volatile("": : :"memory");
@ -126,25 +113,20 @@ static void TXDec(uint32_t v) {
}
/* Validate address */
static bool validate_addr(uint16_t addr) {
static bool validate_addr(uint32_t addr) {
// PC must point into the text (CODE) area
if (addr >= (uint32_t)&_sfixed && addr <= (uint32_t)&_efixed)
// Address must be in SRAM (0x20070000 - 0x20088000)
if (addr >= 0x20070000 && addr < 0x20088000)
return true;
// Or into the SRAM function area
if (addr >= (uint32_t)&_srelocate && addr <= (uint32_t)&_erelocate)
return true;
// SP must point into the allocated stack area
if (addr >= (uint32_t)&_sstack && addr <= (uint32_t)&_estack)
// 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;
@ -153,7 +135,6 @@ static bool UnwReadW(const uint32_t a, uint32_t *v) {
}
static bool UnwReadH(const uint32_t a, uint16_t *v) {
if (!validate_addr(a))
return false;
@ -162,7 +143,6 @@ static bool UnwReadH(const uint32_t a, uint16_t *v) {
}
static bool UnwReadB(const uint32_t a, uint8_t *v) {
if (!validate_addr(a))
return false;
@ -173,13 +153,27 @@ static bool UnwReadB(const uint32_t a, uint8_t *v) {
// Dump a backtrace entry
static bool UnwReportOut(void* ctx, const UnwReport* bte) {
int* p = (int*)ctx;
TX(bte->name?bte->name:"unknown"); TX('@');TXHex(bte->function);
(*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,
@ -187,7 +181,7 @@ static const UnwindCallbacks UnwCallbacks = {
UnwReadH,
UnwReadB
#if defined(UNW_DEBUG)
,printf
,UnwPrintf
#endif
};
@ -201,24 +195,27 @@ static const UnwindCallbacks UnwCallbacks = {
* 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
@ -241,14 +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");
UnwindFrame 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]);
UnwindStart(&btf, &UnwCallbacks, nullptr);
int ctr = 0;
UnwindStart(&btf, &UnwCallbacks, &ctr);
// Disable all NVIC interrupts
NVIC->ICER[0] = 0xFFFFFFFF;
@ -274,7 +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"
);
}
@ -285,7 +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"
);
}
@ -296,7 +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"
);
}
@ -307,7 +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"
);
}
@ -318,7 +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"
);
}
@ -329,18 +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"
);
}
@ -351,7 +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

@ -79,7 +79,7 @@ void UnwInitState(UnwState * const state, /**< Pointer to structure to fill.
// Detect if function names are available
static int __attribute__ ((noinline)) has_function_names(void) {
uint32_t flag_word = ((uint32_t*)&has_function_names)[-1];
uint32_t flag_word = ((uint32_t*)(((uint32_t)(&has_function_names)) & (-4))) [-1];
return ((flag_word & 0xff000000) == 0xff000000) ? 1 : 0;
}
@ -93,7 +93,7 @@ bool UnwReportRetAddr(UnwState * const state, uint32_t addr) {
// We found two acceptable values.
entry.name = NULL;
entry.address = addr;
entry.address = addr & 0xFFFFFFFE; // Remove Thumb bit
entry.function = 0;
// If there are function names, try to solve name
@ -108,7 +108,7 @@ bool UnwReportRetAddr(UnwState * const state, uint32_t addr) {
uint32_t v;
while(state->cb->readW(pf-4,&v)) {
// Check if name descriptor is valid and name is terminated in 0.
// Check if name descriptor is valid
if ((v & 0xffffff00) == 0xff000000 &&
(v & 0xff) > 1) {

View File

@ -38,6 +38,8 @@ 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;
@ -61,12 +63,332 @@ UnwResult UnwStartThumb(UnwState * const state) {
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);
}
/*
* 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);
}
}
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
*/
if((instr & 0xe000) == 0x0000 && (instr & 0x1800) != 0x1800) {
else if((instr & 0xe000) == 0x0000 && (instr & 0x1800) != 0x1800) {
bool signExtend;
uint8_t op = (instr & 0x1800) >> 11;
uint8_t offset5 = (instr & 0x07c0) >> 6;
@ -355,8 +677,8 @@ UnwResult UnwStartThumb(UnwState * const state) {
}
/* Format 5: Hi register operations/branch exchange
* ADD Rd, Hs
* ADD Hd, Rs
* ADD Hd, Hs
* CMP Hd, Rs
* MOV Hd, Hs
*/
else if((instr & 0xfc00) == 0x4400) {
uint8_t op = (instr & 0x0300) >> 8;
@ -371,11 +693,6 @@ UnwResult UnwStartThumb(UnwState * const state) {
if(h1)
rhd += 8;
if(op != 3 && !h1 && !h2) {
UnwPrintd1("\nError: h1 or h2 must be set for ADD, CMP or MOV\n");
return UNWIND_ILLEGAL_INSTR;
}
switch(op) {
case 0: /* ADD */
UnwPrintd5("ADD r%d, r%d\t; r%d %s", rhd, rhs, rhs, M_Origin2Str(state->regData[rhs].o));
@ -407,6 +724,10 @@ UnwResult UnwStartThumb(UnwState * const state) {
return UNWIND_TRUNCATED;
}
/* Store return address in LR register */
state->regData[14].v = state->regData[15].v + 2;
state->regData[14].o = REG_VAL_FROM_CONST;
/* Update the PC */
state->regData[15].v = state->regData[rhs].v;
@ -570,10 +891,42 @@ UnwResult UnwStartThumb(UnwState * const state) {
}
}
}
/*
* 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;
int16_t branchValue = signExtend11(instr & 0x07ff);
/* Branch distance is twice that specified in the instruction. */
@ -590,9 +943,17 @@ UnwResult UnwStartThumb(UnwState * const state) {
*/
state->regData[15].v += 2;
/* Display PC of next instruction */
UnwPrintd2(" New PC=%x", 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("????");

View File

@ -22,55 +22,18 @@
#include "unwarm.h"
#include "unwarmbytab.h"
/* 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)) UnwResult 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 UNWIND_SUCCESS;
return UNWIND_INVALID_SP;
}
/* Validate code pointer (PC): It must be either in TEXT or in SRAM */
static inline __attribute__((always_inline)) UnwResult 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 UNWIND_SUCCESS;
// Or into the SRAM function area
if ((uint32_t)pc >= (uint32_t)&_srelocate && (uint32_t)pc <= (uint32_t)&_erelocate)
return UNWIND_SUCCESS;
return UNWIND_INVALID_PC;
}
/* 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) {
return ((char*)(&__exidx_end) - (char*)(&__exidx_start)) > 16 ? 1 : 0; // 16 because there are default entries we can´t supress
// > 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)
{
UnwResult UnwindStart(UnwindFrame* frame, const UnwindCallbacks *cb, void *data) {
if (HasUnwindTableInfo()) {
/* We have unwind information tables */

View File

@ -149,7 +149,7 @@ typedef struct {
#if defined(UNW_DEBUG)
/** Print a formatted line for debug. */
int (*printf)(const char *format, ...);
void (*printf)(const char *format, ...);
#endif
} UnwindCallbacks;
@ -169,6 +169,11 @@ extern "C" {
* 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);