rockbox/lib/unwarminder/unwarmmem.c
Marcin Bukat b4eab59951 Arm stack unwinder
Simplified stack unwinder for ARM. This is port of
http://www.mcternan.me.uk/ArmStackUnwinding/
backtrace() is called from UIE() on native targets
and from panicf() on both native and ARM RaaA.

Change-Id: I8e4b3c02490dd60b30aa372fe842d193b8929ce0
2012-02-22 08:33:26 +01:00

175 lines
4.9 KiB
C

/***************************************************************************
* 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: Implementation of the memory tracking sub-system.
**************************************************************************/
#define MODULE_NAME "UNWARMMEM"
/***************************************************************************
* Include Files
**************************************************************************/
#include "types.h"
#include <stdio.h>
#include "unwarmmem.h"
#include "unwarm.h"
/***************************************************************************
* Manifest Constants
**************************************************************************/
/***************************************************************************
* Type Definitions
**************************************************************************/
/***************************************************************************
* Variables
**************************************************************************/
/***************************************************************************
* Macros
**************************************************************************/
#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)))
/***************************************************************************
* Local Functions
**************************************************************************/
/** 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 SignedInt16 memHashIndex(MemData * const memData,
const Int32 addr)
{
const Int16 v = addr % MEM_HASH_SIZE;
Int16 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;
}
/***************************************************************************
* Global Functions
**************************************************************************/
Boolean UnwMemHashRead(MemData * const memData,
Int32 addr,
Int32 * const data,
Boolean * const tracked)
{
SignedInt16 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;
}
}
Boolean UnwMemHashWrite(MemData * const memData,
Int32 addr,
Int32 val,
Boolean valValid)
{
SignedInt16 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 Int32 minValidAddr = state->regData[13].v;
MemData * const memData = &state->memData;
Int16 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);
}
}
}
/* END OF FILE */