[2.0.x] Move backtrace to a shared location (#10237)

- And implement the `backtrace()` function call

Marlin/src/backtrace/unwarm.h

@@ -0,0 +1,147 @@
+/***************************************************************************
+ * 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.
+   */
+  int o; /* (RegValOrigin) */
+} 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
+ **************************************************************************/
+
+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);
+
+#endif /* UNWARM_H */
+
+/* END OF FILE */
+
+