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Re: [PATCH] arm reversible : progress <patch_1_phase_2>


Hi,

I am done with the deisng for both thumb and arm framework.
coding guidelines are improved.

having some doubts as of now.

1) what is the API to read arm coprocessor registers ?
2) how to read SPSR value ?
3) there are couple of FIX me in code.

PS: patch progress is posted below. phase 3 will include thumb insn decoding 
part.phase 4 will include arm-linux ABI part.

PATCH STARTS
------------------------------------
diff -urN arm_new/arm-linux-tdep.c arm_orig/arm-linux-tdep.c
--- arm_new/arm-linux-tdep.c    2011-03-03 09:15:59.000000000 +0530
+++ arm_orig/arm-linux-tdep.c    2011-03-03 09:21:13.000000000 +0530
@@ -998,9 +998,6 @@
   set_gdbarch_fetch_tls_load_module_address (gdbarch,
                                              svr4_fetch_objfile_link_map);
 
-  /* Enable process record */
-  set_gdbarch_process_record(gdbarch, arm_process_record);
-
   tramp_frame_prepend_unwinder (gdbarch,
                 &arm_linux_sigreturn_tramp_frame);
   tramp_frame_prepend_unwinder (gdbarch,
diff -urN arm_new/arm-tdep.c arm_orig/arm-tdep.c
--- arm_new/arm-tdep.c    2011-03-03 09:15:59.000000000 +0530
+++ arm_orig/arm-tdep.c    2011-03-03 09:21:13.000000000 +0530
@@ -54,11 +54,8 @@
 #include "gdb_assert.h"
 #include "vec.h"
 
-#include "record.h"
-
 #include "features/arm-with-m.c"
 
-
 static int arm_debug;
 
 /* Macros for setting and testing a bit in a minimal symbol that marks
@@ -7932,1168 +7929,3 @@
                NULL, /* FIXME: i18n: "ARM debugging is %s.  */
                &setdebuglist, &showdebuglist);
 }
-
-
-
-/* arm-reversible process reacord data structures */
-
-#define ARM_INSN_SIZE_BYTES 4    
-#define THUMB_INSN_SIZE_BYTES 2
-#define NO_OF_TYPE_OF_ARM_INSNS 8
-#define NO_OF_TYPE_OF_THUMB_INSNS 8
-
-#define ARM_RECORD_ARCH_LIST_ADD_REG(regnum) \
-    record_arch_list_add_reg (arm_record.regcache, regnum)
-
-#define GET_REG_VAL(REGCACHE,NO,BUF)  regcache_raw_read (REGCACHE, NO, BUF);
-
-#define IS_IT_ARM_INSN(X) ((X & 0x00000010) >> 4)
-#define ARM_PARSE_INSN(X,BIT_POS,NO_OF_BITS) \
-                ((X >> (BIT_POS-1)) & (0xFFFFFFFF >> ((sizeof(uint32_t)*8) - \
-                  NO_OF_BITS)))
-
-#define INSN_S_L_BIT_NUM 21
-#define ARM_BIT_SET(X, NUM) (((X >> (NUM-1)) & 0x00000001) == 1)  
-#define GET_BIT(X, NUM) (((X >> (NUM-1)) & 0x00000001))
-
-
-
-int arm_handle_data_proc_misc_load_str_insn (void*);
-int arm_handle_data_proc_misc_load_str_insn (void*);
-int arm_handle_data_proc_imm_insn (void*);
-int arm_handle_ld_st_imm_offset_insn (void*);
-int arm_handle_ld_st_reg_offset_insn (void*);
-int arm_hamdle_ld_st_multiple_insn (void*);
-int arm_handle_brn_insn (void*);
-int arm_handle_coproc_insn (void*);
-int arm_handle_coproc_data_proc_insn (void*);
-
-int thumb_handle_shift_add_sub_insn (void*);         
-int thumb_handle_data_proc_load_strbrn_insn (void*); 
-int thumb_handle_ld_st_reg_offset_insn (void*);      
-int thumb_handle_ld_st_imm_offset_insn (void*);      
-int thumb_hamdle_ld_st_stack_insn (void*);        
-int thumb_handle_misc_insn (void*);             
-int thumb_handle_swi_insn (void*);                    
-int thumb_handle_branch_insn (void*);                
-
-
-/* (starting from numerical 0); bits 25,26,27 decodes type of arm instruction 
*/
-int (*const arm_handle_insn[NO_OF_TYPE_OF_ARM_INSNS]) (void*) = 
-{ 
-    arm_handle_data_proc_misc_load_str_insn, /* 000 */
-    arm_handle_data_proc_imm_insn,             /* 001 */
-    arm_handle_ld_st_imm_offset_insn,         /* 010 */
-    arm_handle_ld_st_reg_offset_insn,         /* 011 */    
-    arm_hamdle_ld_st_multiple_insn,             /* 100 */
-    arm_handle_brn_insn,                     /* 101 */
-    arm_handle_coproc_insn,                     /* 110 */
-    arm_handle_coproc_data_proc_insn         /* 111 */    
-};
-
-/* (starting from numerical 0); bits 13,14,15 decodes type of thumb instruction 
*/
-int (*const thumb_handle_insn[NO_OF_TYPE_OF_THUMB_INSNS]) (void*) = 
-{ 
-    thumb_handle_shift_add_sub_insn,          /* 000 */
-    thumb_handle_data_proc_load_strbrn_insn, /* 001 */
-    thumb_handle_ld_st_reg_offset_insn,         /* 010 */
-    thumb_handle_ld_st_imm_offset_insn,         /* 011 */    
-    thumb_hamdle_ld_st_stack_insn,             /* 100 */
-    thumb_handle_misc_insn,                     /* 101 */
-    thumb_handle_swi_insn,                     /* 110 */
-    thumb_handle_branch_insn                  /* 111 */    
-};
-
-
-struct arm_mem_r
-{
-    uint32_t len;
-    CORE_ADDR addr;
-};
-
-typedef struct arm_insn_decode_record_t
-{
-  struct gdbarch *gdbarch;
-  struct regcache *regcache;
-  CORE_ADDR this_addr;          /* address of the insn being decoded */
-  uint32_t arm_insn;            /* should accomodate thumb */
-  uint32_t cond;                /* condition code */
-  uint32_t id;                  /* type of insn */
-  uint32_t opcode;              /* insn opcode */
-  uint32_t decode;              /* insn decode bits */
-  uint32_t *arm_regs;           /* registers to be saved for this record */
-  struct arm_mem_r *arm_mems;   /* memory to be saved for this record */
-} arm_insn_decode_record;
-
-
-int 
-decode_insn (arm_insn_decode_record *arm_record, uint32_t insn_size)
-{
-  union
-    {
-      uint32_t s_word;
-      gdb_byte buf[insn_size];
-    } u_buf;
-
-  memset (&u_buf, 0, sizeof(u_buf));
-  if (target_read_memory (arm_record->this_addr, &u_buf.buf[0], insn_size))    
-    {        
-      if (record_debug)
-        {
-          printf_unfiltered (_("Process record: error reading memory at "
-                               "addr %s len = %d.\n"),
-          paddress (arm_record->gdbarch, arm_record->this_addr), insn_size);
-          return -1;
-        }
-    }
-  else if(ARM_INSN_SIZE_BYTES == insn_size)
-    {
-      arm_record->arm_insn = u_buf.s_word;
-      arm_record->id = ARM_PARSE_INSN (arm_record->arm_insn,26,3);
-      arm_handle_insn[arm_record->id] ((void*)arm_record);
-    }    
-  else if(THUMB_INSN_SIZE_BYTES == insn_size)
-    {
-      arm_record->arm_insn = u_buf.s_word;  
-      arm_record->id = ARM_PARSE_INSN (arm_record->arm_insn,14,3);
-      thumb_handle_insn[arm_record->id] ((void*)arm_record);
-    }
-  return 0;
-}
-
-/* Parse the current instruction and record the values of the registers and
-   memory that will be changed in current instruction to "record_arch_list".
-   Return -1 if something is wrong. */
-
-int 
-arm_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
-                             CORE_ADDR insn_addr)
-{
-
-  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);  
-  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
-  int no_of_rec=0;
-
-  union
-    {
-      uint32_t s_word;
-      gdb_byte buf[4];
-    } u_buf;
-
-  arm_insn_decode_record arm_record;
-
-  memset (&u_buf, 0, sizeof(u_buf));
-  memset (&arm_record, 0, sizeof (arm_insn_decode_record));
-  arm_record.regcache = regcache;
-  arm_record.this_addr = insn_addr;
-  arm_record.gdbarch = gdbarch;
-
-
-  if (record_debug > 1)
-    {
-      fprintf_unfiltered (gdb_stdlog, "Process record: arm_process_record "
-                                      "addr = %s\n",
-      paddress (gdbarch, arm_record.this_addr));
-    }
-
-  /* check the insn, whether it is thumb or arm one */
-  GET_REG_VAL (arm_record.regcache, ARM_PS_REGNUM, &u_buf.buf[0]);
-  if (IS_IT_ARM_INSN (u_buf.s_word))
-    {
-      /* we are decoding arm insn */
-      decode_insn (&arm_record, 4);
-    }
-  else
-    {
-      /* we are decoding thumb insn */
-      decode_insn (&arm_record, 2);    
-    }
-
-  /* record registers */
-  ARM_RECORD_ARCH_LIST_ADD_REG(ARM_PC_REGNUM);
-  if(arm_record.arm_regs)
-    {
-      for(no_of_rec=1;no_of_rec<=arm_record.arm_regs[0];no_of_rec++)
-        {
-          if(ARM_RECORD_ARCH_LIST_ADD_REG (arm_record.arm_regs[no_of_rec]))
-          return -1;
-        }
-    }   
-  /* record memories */
-  if(arm_record.arm_mems)
-    {
-      for(no_of_rec=1;no_of_rec<=arm_record.arm_mems[0].len;no_of_rec++)
-       {
-          if(record_arch_list_add_mem \
-            ((CORE_ADDR)arm_record.arm_mems[no_of_rec].addr,
-            arm_record.arm_mems[no_of_rec].len))
-            return -1;
-       }
-    }
-
-  if (record_arch_list_add_end ())
-    return -1;
-
-  xfree (arm_record.arm_regs);
-  xfree (arm_record.arm_mems);
-  return 0; 
-}
-
-int 
-arm_handle_data_proc_misc_load_str_insn (void *data)
-{
-
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = gdbarch_tdep ((struct gdbarch*) 
arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  union
-    {
-      uint32_t s_word;
-      gdb_byte buf[4];
-    } u_buf[2];
-
-
-  uint32_t reg_val1=0,reg_val2=0;
-  uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
-  uint32_t immed_high=0,immed_low=0,offset_8=0,tgt_mem_addr=0;
-
-  memset(&u_buf, 0, sizeof(u_buf));
-
-  arm_insn_r->opcode = ARM_PARSE_INSN (arm_insn_r->arm_insn,22,4);
-  arm_insn_r->decode = ARM_PARSE_INSN (arm_insn_r->arm_insn,5,4);
-
-  if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_L_BIT_NUM)) 
-    {
-    /* data processing insn /multiply sinsn */     
-    if(9 == arm_insn_r->decode)
-      {
-      /* handle multiply instructions */
-      /* MLA, MUL, SMLAL, SMULL, UMLAL, UMULL */
-        if((0 == arm_insn_r->opcode) || (1 == arm_insn_r->opcode))
-          {
-            /* handle MLA and MUL */
-            arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-            arm_insn_r->arm_regs[0] = 2;
-            arm_insn_r->arm_regs[1] = ARM_PARSE_INSN \
-                                      (arm_insn_r->arm_insn,17,4);
-            arm_insn_r->arm_regs[2] = ARM_PS_REGNUM;
-          }
-        else if((4 <= arm_insn_r->opcode) && (7 >= arm_insn_r->opcode))
-         {
-          /* handle SMLAL, SMULL, UMLAL, UMULL */
-           arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*4);
-           arm_insn_r->arm_regs[0] = 3;
-           arm_insn_r->arm_regs[1] = ARM_PARSE_INSN 
(arm_insn_r->arm_insn,17,4);
-           arm_insn_r->arm_regs[2] = ARM_PARSE_INSN 
(arm_insn_r->arm_insn,13,4);
-           arm_insn_r->arm_regs[3] = ARM_PS_REGNUM;  
-         }        
-      }
-    else if((11 == arm_insn_r->decode) || (13 == arm_insn_r->decode))
-      {
-        /* handle misc load insns, as 20th bit (L = 1) */
-        /* LDR insn has a capability to do branching, if
-        MOV LR, PC is precedded by LDR insn having Rn as R15 
-        in that case, it emulates branch and link insn, and hence we 
-        need to save CSPR and PC as well. I am not sure this is right 
-        place as opcode = 010 LDR insn make this happen, if R15 was 
-        used. */
-        reg_dest = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
-        if(15 != reg_dest)
-          {
-            arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-            arm_insn_r->arm_regs[0] = 1;
-            arm_insn_r->arm_regs[1] = ARM_PARSE_INSN \
-                                      (arm_insn_r->arm_insn,13,4);
-          }
-        else
-          {
-            arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-            arm_insn_r->arm_regs[0] = 2;
-            arm_insn_r->arm_regs[1] = reg_dest;
-            arm_insn_r->arm_regs[2] = ARM_PS_REGNUM; 
-          }
-      }
-    else
-      {
-        /* normal data processing insns */
-        /* out of 11 shifter operands mode, all the insn modifies destination 
-          register, which is specified by 13-16 decode */
-        arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-        arm_insn_r->arm_regs[0] = 2;
-        arm_insn_r->arm_regs[0] = ARM_PARSE_INSN (arm_insn_r->arm_insn,13,4);
-        arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;        
-      }
-    }
-  else
-    {
-    /* handle misc, swap insns, and store instructions as 20th bit ((L = 0) */  

-      if(9 == arm_insn_r->decode)
-        {
-          /* Handling SWP, SWPB */
-          /* these insns, changes register and memory as well */
-          if((8 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode))
-            {
-              /* SWP or SWPB insn */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-              arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 

-                                      arm_mem_r)*2);
-              /* get memory address given by Rn */
-              reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4); 
-              GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-              arm_insn_r->arm_mems[0].len = 1;
-              /* SWP insn ?, swaps word */
-              if (8 == arm_insn_r->opcode)
-                {
-                  arm_insn_r->arm_mems[1].len = 4;
-                }
-                else
-                {   
-                  /* SWPB insn, swaps only byte */
-                  arm_insn_r->arm_mems[1].len = 1;
-                }
-              arm_insn_r->arm_mems[1].addr = u_buf[0].s_word;
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PARSE_INSN 
(arm_insn_r->arm_insn,13,4);    

-            }
-        }
-      else if(3 == arm_insn_r->decode)
-        {
-          /* handle BLX, branch and link/exchange */
-          if(9 == arm_insn_r->opcode)
-          {
-            /* branch is chosen by setting T bit of CSPR, bitp[0] of Rm, 
-                         and R14 stores the return address */
-            arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-            arm_insn_r->arm_regs[0] = 2;
-            arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
-            arm_insn_r->arm_regs[2] = ARM_LR_REGNUM;
-          }
-        }
-      else if(7 == arm_insn_r->decode)
-        {
-          /* handle enhanced software breakpoint insn, BKPT */
-          /* CPSR is changed to be executed in ARM state,  disabling normal 
-                interrupts, entering abort mode */
-          /* accorindly to high vector configuration PC is set accordingly */
-          /* Oza: FIX ME ?  what if user hit breakpoint and type reverse, in 
-               that case, we need to go back with previous CSPR and 
-               Program Counter. */
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-          arm_insn_r->arm_regs[0] = 1;
-          arm_insn_r->arm_regs[0] = ARM_PS_REGNUM;
-        }
-      else if(11 == arm_insn_r->decode)
-        {
-        /* handle enhanced store insns and LDRD DSP insn */
-        /* let us begin according to addressing modes for store insns */
-        /* STRH insn, addresing modes are taken following */
-
-          if((14 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode))
-            {
-              /* 1) handle misc store, immediate offset */
-              immed_low = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);
-              immed_high = ARM_PARSE_INSN (arm_insn_r->arm_insn,9,4);
-              reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-              GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);            
-              if(15 == reg_src1)
-                {
-                  /* if R15 was used as Rn, hence current PC+8 */
-                  u_buf[0].s_word = u_buf[0].s_word + 8;
-                }            
-              offset_8 = (immed_high << 4) | immed_low;
-              /* calculate target store address */
-              if(14 == arm_insn_r->opcode)
-                {
-                  tgt_mem_addr = u_buf[0].s_word + offset_8;
-                }
-              else
-                {
-                  tgt_mem_addr = u_buf[0].s_word - offset_8;
-                }
-              arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 

-              arm_mem_r)*2);
-              arm_insn_r->arm_mems[0].len = 1;
-              arm_insn_r->arm_mems[1].len = 2;
-              arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-            }
-          else if((12 == arm_insn_r->opcode) || (8 == arm_insn_r->opcode))
-            {
-              /* 2) store, register offset */
-              /* get Rm */
-              reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);  
-              /* get Rn */
-              reg_src2 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-              GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-              GET_REG_VAL 
(reg_cache,reg_src2,&u_buf[1].buf[0]);                        

-              if(15 == reg_src2)
-                {
-                  /* if R15 was used as Rn, hence current PC+8 */
-                  u_buf[0].s_word = u_buf[0].s_word + 8;
-                }            
-              /* calculate target store address, Rn +/- Rm, register offset */
-              if(12 == arm_insn_r->opcode)
-                {
-                  tgt_mem_addr = u_buf[0].s_word + u_buf[1].s_word;
-                }
-              else
-                {
-                  tgt_mem_addr = u_buf[1].s_word - u_buf[0].s_word;
-                }            
-              arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 

-              arm_mem_r)*2);
-              arm_insn_r->arm_mems[0].len = 1;
-              arm_insn_r->arm_mems[1].len = 2;
-              arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-            }
-          else if((11 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)
-            || (2 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode))
-            {
-              /* 3) store, immediate pre-indexed */            
-              /* 5)  store, immediate post-indexed */
-              immed_low = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);  
-              immed_high = ARM_PARSE_INSN (arm_insn_r->arm_insn,9,4);
-              offset_8 = (immed_high << 4) | immed_low;
-              reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-              GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);
-              /* calculate target store address, Rn +/- Rm, register offset */
-              if((15 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode))
-                {
-                  tgt_mem_addr = u_buf[0].s_word + offset_8;
-                }
-              else
-                {
-                  tgt_mem_addr = u_buf[0].s_word - offset_8;
-                }            
-              arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 

-              arm_mem_r)*2);
-              arm_insn_r->arm_mems[0].len = 1;
-              arm_insn_r->arm_mems[1].len = 2;
-              arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-              /* record Rn also as it changes */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PARSE_INSN \
-                                        (arm_insn_r->arm_insn,17,4);  
-            }
-          else if((9 == arm_insn_r->opcode) || (13 == arm_insn_r->opcode)
-            || (0 == arm_insn_r->opcode) || (4 == arm_insn_r->opcode))
-            {
-              /* 4) store, register pre-indexed */
-              /* 6) store, register post -indexed */
-              reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);  
-              reg_src2 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-              GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-              GET_REG_VAL (reg_cache,reg_src2,&u_buf[1].buf[0]);
-              /* calculate target store address, Rn +/- Rm, register offset */
-              if((13 == arm_insn_r->opcode) || (4 == arm_insn_r->opcode))
-                {
-                  tgt_mem_addr = u_buf[0].s_word + u_buf[1].s_word;
-                }
-              else
-                {
-                  tgt_mem_addr = u_buf[1].s_word - u_buf[0].s_word;
-                }            
-              arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 

-              arm_mem_r)*2);
-              arm_insn_r->arm_mems[0].len = 1;
-              arm_insn_r->arm_mems[1].len = 2;
-              arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-              /* record Rn also as it changes */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PARSE_INSN \
-                                        
(arm_insn_r->arm_insn,17,4);              

-            }
-          /* DSP LDRD TBD */
-        }
-      else if(1 == arm_insn_r->decode)
-        {
-          /* handle BLX, branch and link/exchange */
-          if(2 == arm_insn_r->opcode)
-            {
-              /* branch is chosen by setting T bit of CSPR, bitp[0] of Rm */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
-            }
-          else if(11 == arm_insn_r->opcode)
-            {
-              /* count leading zeros: CLZ */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PARSE_INSN \
-                                        (arm_insn_r->arm_insn,13,4);
-            }
-        }
-      else if((8 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode))
-        {
-          /* handle MRS insn*/
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-          arm_insn_r->arm_regs[0] = 1;
-          arm_insn_r->arm_regs[1] = ARM_PARSE_INSN 
(arm_insn_r->arm_insn,13,4);  

-        }
-      else if ((9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode))
-        {
-        /* handle MSR insn*/
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-          if (9 == arm_insn_r->opcode)
-            {
-              /*CSPR is going to be changed */
-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
-            }    
-          else
-          {
-            /* SPSR is going to be changed */
-            /* Oza: FIX ME ? how to read SPSR value ?*/
-          }
-        }   
-    }    
-  return 0;
-}
-
-int 
-arm_handle_data_proc_imm_insn (void *data)
-{
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = \
-                          gdbarch_tdep ((struct gdbarch*) arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  uint32_t reg_val1=0,reg_val2=0;
-  uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
-  uint32_t immed_high=0,immed_low=0,offset_8=0,tgt_mem_addr=0;
-
-  arm_insn_r->opcode = ARM_PARSE_INSN (arm_insn_r->arm_insn,22,4);
-  arm_insn_r->decode = ARM_PARSE_INSN (arm_insn_r->arm_insn,5,4);
-
-  if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_L_BIT_NUM)) 
-    {
-      /* data processing insn, e.g. MOV */                
-      arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-      arm_insn_r->arm_regs[0] = 2;
-      arm_insn_r->arm_regs[1] = ARM_PARSE_INSN (arm_insn_r->arm_insn,13,4);
-      arm_insn_r->arm_regs[2] = ARM_PS_REGNUM;       
-    }
-  else
-    {
-      /* handle MSR insn, status register access */
-      arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-      /*CSPR is going to be changed */
-      arm_insn_r->arm_regs[0] = 1;
-      arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;                
-    }
-  return 0;
-}
-
-int 
-arm_handle_ld_st_imm_offset_insn (void *data)
-{
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = \
-                          gdbarch_tdep ((struct gdbarch*) arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  uint32_t reg_val1=0,reg_val2=0;
-  uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
-  uint32_t immed_high=0,immed_low=0,offset_12=0,tgt_mem_addr=0;
-
-  union
-    {
-      uint32_t s_word;
-      gdb_byte buf[4];
-    } u_buf;
-
-  memset(&u_buf, 0, sizeof(u_buf));
-  arm_insn_r->opcode = ARM_PARSE_INSN (arm_insn_r->arm_insn,22,4);
-  arm_insn_r->decode = ARM_PARSE_INSN (arm_insn_r->arm_insn,5,4);
-
-  if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_L_BIT_NUM)) 
-    {
-      reg_dest = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
-      /* LDR insn has a capability to do branching, if
-      MOV LR, PC is precedded by LDR insn having Rn as R15 
-      in that case, it emulates branch and link insn, and hence we 
-      need to save CSPR and PC as well. */
-      if(15 != reg_dest)
-        {
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-          arm_insn_r->arm_regs[0] = 1;
-          arm_insn_r->arm_regs[1] = ARM_PARSE_INSN (arm_insn_r->arm_insn,13,4);
-        }
-      else
-        {
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-          arm_insn_r->arm_regs[0] = 2;
-          arm_insn_r->arm_regs[1] = reg_dest;
-          arm_insn_r->arm_regs[2] = ARM_PS_REGNUM; 
-        }
-    }
-  else
-    {
-      if((8 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode)     
-      || (12 == arm_insn_r->opcode) || (14 == arm_insn_r->opcode)
-      || (9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode)     
-      || (13 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)         
-      || (0 == arm_insn_r->opcode) || (2 == arm_insn_r->opcode)     
-      || (4 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode)
-      || (1 == arm_insn_r->opcode) || (3 == arm_insn_r->opcode)
-      || (5 == arm_insn_r->opcode) || (7 == arm_insn_r->opcode))
-        {
-          /* store, immediate offset, immediate pre-indexed, immediate 
post-indeed */
-          reg_src1= ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-          offset_12 = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,12);
-          GET_REG_VAL (reg_cache,reg_src1,&u_buf.buf[0]);
-          /* U == 1 */
-          if (ARM_BIT_SET (arm_insn_r->arm_insn,24))
-            {   
-              tgt_mem_addr =  u_buf.s_word + offset_12;
-            }
-          else
-            {
-             tgt_mem_addr =  u_buf.s_word - offset_12;
-            }
-
-          arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-          arm_mem_r)*2);
-          arm_insn_r->arm_mems[0].len = 1;
-
-          switch(arm_insn_r->opcode)
-            {
-              case 8:
-              case 12:          
-              case 9:   
-              case 13:   
-              case 1:   
-              case 5:               
-                /* STR insn, STRT insn */
-                arm_insn_r->arm_mems[1].len = 4;    
-              break;   
-
-              case 10:
-              case 14:            
-              case 11:   
-              case 15:   
-              case 3:   
-              case 7:   
-                /* STRB insn, STRBT insn  */
-                arm_insn_r->arm_mems[1].len = 1;    
-              break;   
-
-              default:
-                /* rest of the insns are unreachable for this addressing mode 
*/
-              break;   
-            }       
-          arm_insn_r->arm_mems[1].addr = tgt_mem_addr;    
-          if((9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode)     
-          || (13 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)
-          || (0 == arm_insn_r->opcode) || (2 == arm_insn_r->opcode)     
-          || (4 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode)          
-          || (1 == arm_insn_r->opcode) || (3 == arm_insn_r->opcode)
-          || (5 == arm_insn_r->opcode) || (7 == arm_insn_r->opcode))
-            {
-              /* we are handling pre-indexed mode; post-indexed mode;
-              where Rn is going to be changed */
-              arm_insn_r->arm_regs = (uint32_t*)xmalloc 
(sizeof(uint32_t)*2);     

-              arm_insn_r->arm_regs[0] = 1;
-              arm_insn_r->arm_regs[1] = reg_src1;    
-            }  
-        }  
-    }
-  return 0;
-}
-
-int 
-arm_handle_ld_st_reg_offset_insn (void *data)
-{
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = \
-                           gdbarch_tdep ((struct gdbarch*) 
arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  uint32_t reg_val1=0,reg_val2=0,shift_imm=0;
-  uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
-  uint32_t immed_high=0,immed_low=0,offset_12=0,tgt_mem_addr=0;
-
-  union
-    {
-      int32_t signed_word;
-      uint32_t s_word;
-      gdb_byte buf[4];
-    } u_buf[2];
-
-  memset(&u_buf, 0, sizeof(u_buf));
-  arm_insn_r->opcode = ARM_PARSE_INSN (arm_insn_r->arm_insn,22,4);
-  arm_insn_r->decode = ARM_PARSE_INSN (arm_insn_r->arm_insn,5,4);
-
-  /* handle enhanced store insns and LDRD DSP insn */
-  /* let us begin according to addressing modes for store insns */
-  /* STRH insn */
-
-  /* LDR or STR ? */
-  if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_L_BIT_NUM))
-    {
-      reg_dest = ARM_PARSE_INSN (arm_insn_r->arm_insn,13,4);
-      /* LDR insn has a capability to do branching, if
-      MOV LR, PC is precedded by LDR insn having Rn as R15 
-      in that case, it emulates branch and link insn, and hence we 
-      need to save CSPR and PC as well. */
-      if(15 != reg_dest)
-        {
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-          arm_insn_r->arm_regs[0] = 1;
-          arm_insn_r->arm_regs[1] = ARM_PARSE_INSN (arm_insn_r->arm_insn,13,4);
-        }
-      else
-        {
-          arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-          arm_insn_r->arm_regs[0] = 2;
-          arm_insn_r->arm_regs[1] = reg_dest;
-          arm_insn_r->arm_regs[2] = ARM_PS_REGNUM; 
-        } 
-    }
-  else
-    {
-    if((8 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode)     
-    || (12 == arm_insn_r->opcode) || (14 == arm_insn_r->opcode)
-    || (9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode)     
-    || (13 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)         
-    || (0 == arm_insn_r->opcode) || (2 == arm_insn_r->opcode)     
-    || (4 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode)         
-    || (1 == arm_insn_r->opcode) || (3 == arm_insn_r->opcode)
-    || (5 == arm_insn_r->opcode) || (7 == arm_insn_r->opcode))
-      {
-        if(!ARM_PARSE_INSN(arm_insn_r->arm_insn,5,8))
-          {
-            /* store insn, register offset and register pre-indexed, 
-            register post-indexed */
-            /* get Rm */
-            reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);  
-            /* get Rn */
-            reg_src2 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-            GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-            GET_REG_VAL 
(reg_cache,reg_src2,&u_buf[1].buf[0]);                        

-            if(15 == reg_src2)
-              {
-                /* if R15 was used as Rn, hence current PC+8 */
-                /* pre-indexed mode doesnt reach here ; illegal insn */
-                u_buf[0].s_word = u_buf[0].s_word + 8;
-              }            
-            /* calculate target store address, Rn +/- Rm, register offset */
-            /* U == 1 */
-            if (ARM_BIT_SET (arm_insn_r->arm_insn,24))
-              {
-                tgt_mem_addr = u_buf[0].s_word + u_buf[1].s_word;
-              }
-            else
-              {
-                tgt_mem_addr = u_buf[1].s_word - u_buf[0].s_word;
-              }            
-            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-            arm_mem_r)*2);
-            arm_insn_r->arm_mems[0].len = 1;
-            switch(arm_insn_r->opcode)
-              {
-                case 8:
-                case 12:          
-                case 9:   
-                case 13:   
-                case 1:   
-                case 5:               
-                  /* STR insn, STRT insn */
-                  arm_insn_r->arm_mems[1].len = 4;    
-                break;   
-
-                case 10:
-                case 14:            
-                case 11:   
-                case 15:   
-                case 3:   
-                case 7:   
-                  /* STRB insn, STRBT insn  */
-                  arm_insn_r->arm_mems[1].len = 1;    
-                break;   
-
-                default:
-                  /* rest of the insns are unreachable for this addr mode */
-                break;   
-              }       
-            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-
-            if ((9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode)     
-            || (13 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)
-            || (0 == arm_insn_r->opcode) || (2 == arm_insn_r->opcode)     
-            || (4 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode)         
-            || (1 == arm_insn_r->opcode) || (3 == arm_insn_r->opcode)
-            || (5 == arm_insn_r->opcode) || (7 == arm_insn_r->opcode))
-              {
-                arm_insn_r->arm_regs = \
-                (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-                arm_insn_r->arm_regs[0] = 1;
-                /* Rn is going to be changed in pre-indexed mode and 
-                post-indexed mode as well */
-                arm_insn_r->arm_regs[1] = reg_src2;  
-              }     
-          }
-        else
-          {
-            /* store insn, scaled register offset; scaled pre-indexed */
-            offset_12 = ARM_PARSE_INSN (arm_insn_r->arm_insn,6,2);
-            /* get Rm */
-            reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,4);  
-            /* get Rn */
-            reg_src2 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-            /* get shift_imm */
-            shift_imm = ARM_PARSE_INSN (arm_insn_r->arm_insn,8,5);
-            GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-            GET_REG_VAL (reg_cache,reg_src2,&u_buf[1].buf[0]);   
-            /* offset_12 used as shift */
-            switch(offset_12)
-              {
-                case 0:
-                  /* offset_12 used as index */
-                  offset_12 = u_buf[0].s_word << shift_imm;
-                break;
-                
-                case 1:
-                  offset_12 = (!shift_imm)?0:u_buf[0].s_word >> shift_imm; 
-                break;
-                
-                case 2:
-                  if(!shift_imm)
-                    {
-                      if(ARM_BIT_SET (u_buf[0].s_word,32))
-                        {
-                          offset_12 = 0xFFFFFFFF;
-                        }
-                      else
-                        {
-                          offset_12 = 0;
-                        }
-                    }
-                  else
-                    {
-                      /* this is arithmetic shift */
-                      offset_12 = u_buf[0].signed_word >> shift_imm;
-                    }
-                  break;  
-                  
-                case 3:
-                  if(!shift_imm)
-                    {
-                      GET_REG_VAL (reg_cache,ARM_PS_REGNUM,&u_buf[1].buf[0]);
-                      /* get C flag value and shift it by 31 */
-                      offset_12 = (((GET_BIT (u_buf[1].s_word,30)) << 31) \
-                                    | (u_buf[0].s_word) >> 1);
-                    }
-                  else
-                    {                      
-                      offset_12 = (u_buf[0].s_word >> shift_imm) \
-                            | (u_buf[0].s_word << 
(sizeof(uint32_t)-shift_imm));
-                    }
-                break;
-
-                default:
-                  /* unreachable */  
-                break;
-              }      
-
-            GET_REG_VAL (reg_cache,reg_src2,&u_buf[1].buf[0]); 
-            /* U == 1 */
-            if (ARM_BIT_SET (arm_insn_r->arm_insn,24))
-              {
-                tgt_mem_addr = u_buf[1].s_word + offset_12;
-              }
-            else
-              {
-                tgt_mem_addr = u_buf[1].s_word - offset_12;
-              }                       
-            switch(arm_insn_r->opcode)
-              {
-                case 8:
-                case 12:          
-                case 9:   
-                case 13:   
-                case 1:   
-                case 5:               
-                  /* STR insn, STRT insn */
-                  arm_insn_r->arm_mems[1].len = 4;    
-                break;   
-
-                case 10:
-                case 14:            
-                case 11:   
-                case 15:   
-                case 3:   
-                case 7:   
-                  /* STRB insn, STRBT insn  */
-                  arm_insn_r->arm_mems[1].len = 1;    
-                break;   
-
-                default:
-                  /* rest of the insns are unreachable for this addr mode */
-                break;   
-              }       
-            arm_insn_r->arm_mems = (struct arm_mem_r *)
-            xmalloc (sizeof(struct arm_mem_r)*2);
-            arm_insn_r->arm_mems[0].len = 1;
-            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
-
-            if ((9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode)     
-            || (13 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)
-            || (0 == arm_insn_r->opcode) || (2 == arm_insn_r->opcode)     
-            || (4 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode)         
-            || (1 == arm_insn_r->opcode) || (3 == arm_insn_r->opcode)
-            || (5 == arm_insn_r->opcode) || (7 == arm_insn_r->opcode))
-              {
-                arm_insn_r->arm_regs = \
-                (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-                arm_insn_r->arm_regs[0] = 1;
-                /* Rn is going to be changed in register scaled pre-indexed 
-                mode, and scaled post indexed mode */
-                arm_insn_r->arm_regs[1] = reg_src2;  
-              }
-          }            
-      }  
-    }
-  return 0;   
-}
-
-int 
-arm_hamdle_ld_st_multiple_insn (void *data)
-{   
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = \
-                            gdbarch_tdep ((struct gdbarch*) 
arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  uint32_t register_list[16]={0}, register_count=0, register_bits=0;       
-  uint32_t reg_val1=0, reg_val2=0, shift_imm=0;
-  uint32_t reg_src1=0, reg_src2=0, addr_mode=0;
-  uint32_t start_address=0;
-
-  union
-    {
-      uint32_t s_word;
-      gdb_byte buf[4];
-    } u_buf[2];
-
-  memset (&u_buf, 0, sizeof(u_buf));
-
-  /* this mode is exclusively for load and store multiple */
-  /* handle incremenrt after/before and decrment after.before mode;
-  Rn is chaging depending on W bit, but as of now we store Rn too wihtout going 
for 

-  optmization, */
-
-
-  if (ARM_BIT_SET (arm_insn_r->arm_insn, INSN_S_L_BIT_NUM))
-    {
-      /* LDR (1,2,3) where LDR (3) changes CPSR too */
-
-      register_bits = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,16);
-      /* get Rn */
-      reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
-      while(register_bits)
-        {
-          register_list[register_count++] = register_bits & 0x00000001;
-          register_bits = register_bits >> 1;
-        }
-        /* extra space for Base Register and CPSR; wihtout optmization */
-        arm_insn_r->arm_regs = (uint32_t*)xmalloc \
-                                      
(sizeof(uint32_t)*(register_count+1+1+1));
-        arm_insn_r->arm_regs[0] = register_count+1+1;
-        arm_insn_r->arm_regs[register_count+1] = reg_src1;
-        arm_insn_r->arm_regs[register_count+2] = ARM_PS_REGNUM;
-      while(register_count)
-        {
-          arm_insn_r->arm_regs[register_count] = \
-          register_list[register_count-1];
-          register_count--;
-        }
-    }
-  else
-    {
-    /* it handles both STM(1) and STM(2) */
-    addr_mode = ARM_PARSE_INSN (arm_insn_r->arm_insn,24,2);    
-
-    register_bits = ARM_PARSE_INSN (arm_insn_r->arm_insn,1,16);
-    /* get Rn */
-    reg_src1 = ARM_PARSE_INSN (arm_insn_r->arm_insn,17,4);
-    GET_REG_VAL (reg_cache,reg_src1,&u_buf[0].buf[0]);
-    while(register_bits)
-      {
-        if (register_bits & 0x00000001)
-          {
-           register_count++;
-          }
-        register_bits = register_bits >> 1;
-      }
-
-    switch(addr_mode)
-      {
-        /* Decrement after */ 
-        case 0:                          
-          start_address = (u_buf[0].s_word) - (register_count * 4) + 4;
-          arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-          arm_mem_r)*(register_count+1));
-          arm_insn_r->arm_mems[0].len = 1;
-          while(register_count)
-            {
-              arm_insn_r->arm_mems[register_count].addr = start_address;
-              start_address = start_address + 4;
-              register_count--;
-            }
-        break;    
-
-        /* Increment after */
-        case 1:
-          start_address = u_buf[0].s_word;
-          arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-          arm_mem_r)*(register_count+1));
-          arm_insn_r->arm_mems[0].len = 1;
-          while(register_count)
-            {
-              arm_insn_r->arm_mems[register_count].addr = start_address;
-              start_address = start_address + 4;
-              register_count--;
-            }
-        break;    
-
-        /* Decrement before */
-        case 2:
-
-        start_address = (u_buf[0].s_word) - (register_count * 4);
-        arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-        arm_mem_r)*(register_count+1));
-        arm_insn_r->arm_mems[0].len = 1;
-          while(register_count)
-            {
-              arm_insn_r->arm_mems[register_count].addr = start_address;
-              start_address = start_address + 4;
-              register_count--;
-            }
-        break;    
-
-        /* Increment before */
-        case 3:
-          start_address = u_buf[0].s_word + 4;
-          arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc (sizeof(struct 
-          arm_mem_r)*(register_count+1));
-          arm_insn_r->arm_mems[0].len = 1;
-          while(register_count)
-            {
-              arm_insn_r->arm_mems[register_count].addr = start_address;
-              start_address = start_address + 4;
-              register_count--;
-            }
-        break;    
-
-        default:
-          /* unreachable */    
-        break;    
-      }
-
-    /* base register also changes; based on condition and W bit */
-    /* we save it anyway without optimization */
-    arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*2);
-    arm_insn_r->arm_regs[0] = 1;
-    arm_insn_r->arm_regs[register_count+1] = reg_src1;
-    }
-  return 0;   
-}
-
-int 
-arm_handle_brn_insn (void *data)
-{
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data; 
-  /* handle B, BL, BLX(1) insns */
-  /* wihtout optmization we save link register, 
-  CSPR for the insn which changes T bit */
-  arm_insn_r->arm_regs = (uint32_t*)xmalloc (sizeof(uint32_t)*3);
-  arm_insn_r->arm_regs[0] = 2;
-  arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
-  arm_insn_r->arm_regs[2] = ARM_LR_REGNUM;
-  
-  return 0;
-}
-
-int 
-arm_handle_coproc_insn (void *data)
-{
-  arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
-  struct gdbarch_tdep *tdep = \
-                          gdbarch_tdep ((struct gdbarch*) arm_insn_r->gdbarch);
-  struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
-
-  uint32_t register_list[16]={0},register_count=0, register_bits=0;     
-  uint32_t reg_val1=0,reg_val2=0,shift_imm=0;
-  uint32_t reg_src1=0,reg_src2=0,addr_mode=0;
-  uint32_t start_address=0;
-
-  return 0;   
-}
-
-int 
-arm_handle_coproc_data_proc_insn (void *data)
-{
-  /* TBD */
-  return 0;   
-}
-
-
-int 
-thumb_handle_shift_add_sub_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_data_proc_load_strbrn_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_ld_st_reg_offset_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_ld_st_imm_offset_insn (void *data )
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_hamdle_ld_st_stack_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_misc_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_swi_insn (void *data)                
-{
-  /* TBD */
-  return 0;
-}
-
-int 
-thumb_handle_branch_insn (void *data)
-{
-  /* TBD */
-  return 0;
-}
diff -urN arm_new/arm-tdep.h arm_orig/arm-tdep.h
--- arm_new/arm-tdep.h    2011-03-03 09:15:59.000000000 +0530
+++ arm_orig/arm-tdep.h    2011-03-03 09:21:13.000000000 +0530
@@ -310,10 +310,6 @@
                       struct displaced_step_closure *,
                       CORE_ADDR, CORE_ADDR, struct regcache *);
 
-extern int arm_process_record (struct gdbarch *gdbarch,
-                                struct regcache *regcache, CORE_ADDR addr);
-
-
 /* Functions exported from armbsd-tdep.h.  */
 
 /* Return the appropriate register set for the core section identified






----- Original Message ----
From: paawan oza <paawan1982@yahoo.com>
To: "gdb@sourceware.org" <gdb@sourceware.org>
Sent: Wed, February 2, 2011 2:58:44 PM
Subject: [PATCH] arm reversible : progress <patch_1_phase_1>

Hi all,

As I thought, I would be working on arm insn part first and then linux ABI part 
first.
working with arm and thumb insn, I have come up with patch_1 of my phase 1 
activity.
which mainly includes design, few insns, and framework on which I will relying 
on rest of the implementation.
few arm insns are implemented and in place, and I am able to debug following 
samle program too.

PS: I am posting this patch, not with the intension of comletion or getting it 
in mainline. but I thought If I post early I may get some valuable suggestions 
and inputs regarding design and data structures, or have missed to consider some 

arch related issues. I will get to know early before I go forward.
please also ignore coding guidelines as it will be corrected in due timeline.
any inputs and suggestions are welcome.


the samle program is as below.
#include <stdio.h>

void main()
{
     int s;
     s = 10;
     s = 15;
     s = 20;
     s = -30;
     s = 88;
}

<PATCH>
diff -urN arm_orig/arm-linux-tdep.c arm_new/arm-linux-tdep.c
--- arm_orig/arm-linux-tdep.c    2011-02-02 14:22:52.000000000 +0530
+++ arm_new/arm-linux-tdep.c    2011-02-02 14:23:03.000000000 +0530
@@ -998,6 +998,9 @@
   set_gdbarch_fetch_tls_load_module_address (gdbarch,
                                              svr4_fetch_objfile_link_map);

+  /* Enable process record */
+  set_gdbarch_process_record(gdbarch, arm_process_record);
+
   tramp_frame_prepend_unwinder (gdbarch,
                 &arm_linux_sigreturn_tramp_frame);
   tramp_frame_prepend_unwinder (gdbarch,
diff -urN arm_orig/arm-tdep.c arm_new/arm-tdep.c
--- arm_orig/arm-tdep.c    2011-02-02 14:22:53.000000000 +0530
+++ arm_new/arm-tdep.c    2011-02-02 14:23:03.000000000 +0530
@@ -54,8 +54,11 @@
#include "gdb_assert.h"
#include "vec.h"

+#include "record.h"
+
#include "features/arm-with-m.c"

+
static int arm_debug;

/* Macros for setting and testing a bit in a minimal symbol that marks
@@ -7929,3 +7932,576 @@
                NULL, /* FIXME: i18n: "ARM debugging is %s.  */
                &setdebuglist, &showdebuglist);
}
+
+
+
+/* arm-reversible process reacord data structures */
+
+#define NO_OF_TYPE_OF_ARM_INSNS 8
+#define ARM_RECORD_ARCH_LIST_ADD_REG(regnum) \
+    record_arch_list_add_reg (arm_record.regcache, regnum)
+
+#define GET_REG_VAL(REGCACHE,NO,BUF)  regcache_raw_read (REGCACHE, NO, BUF);
+
+#define IS_IT_ARM_INSN(X) ((X & 0x00000010) >> 4)
+#define ARM_PARSE_INSN(X,BIT_POS,NO_OF_BITS) \
+                ((X >> (BIT_POS-1)) & (0xFFFFFFFF >> ((sizeof(uint32_t)*8) - \
+                  NO_OF_BITS)))
+
+/* arm_handle_data_proc_imm_insn */
+#define INSN_S_BIT_NUM 21
+#define ARM_BIT_SET(X, NUM) (((X >> (NUM-1)) & 0x00000001) == 1)  
+
+
+int arm_handle_data_proc_misc_load_str_insn (void*);
+int arm_handle_data_proc_misc_load_str_insn(void*);
+int arm_handle_data_proc_imm_insn(void*);
+int arm_handle_ld_st_imm_offset_insn(void*);
+int arm_handle_ld_st_reg_offset_insn(void*);
+int arm_hamdle_ld_st_multiple_insn(void*);
+int arm_handle_brn_insn(void*);
+int arm_handle_coproc_insn(void*);
+int arm_handle_coproc_data_proc_insn(void*);
+
+int (*const arm_handle_insn[NO_OF_TYPE_OF_ARM_INSNS]) (void*) = 
+{ 
+    arm_handle_data_proc_misc_load_str_insn, 
+    arm_handle_data_proc_imm_insn,
+    arm_handle_ld_st_imm_offset_insn,
+    arm_handle_ld_st_reg_offset_insn,
+    arm_hamdle_ld_st_multiple_insn,
+    arm_handle_brn_insn,
+    arm_handle_coproc_insn,
+    arm_handle_coproc_data_proc_insn
+};
+
+struct arm_mem_r
+{
+    uint32_t len;
+    CORE_ADDR addr;
+};
+
+typedef struct arm_insn_decode_record_t
+{
+  struct gdbarch *gdbarch;
+  struct regcache *regcache;
+  CORE_ADDR this_addr;          /* address of the insn being decoded */
+  uint32_t arm_insn;            /* should accomodate thumb */
+  uint32_t cond;                /* condition code */
+  uint32_t id;                  /* type of insn */
+  uint32_t opcode;              /* insn opcode */
+  uint32_t decode;              /* insn decode bits */
+  uint32_t *arm_regs;           /* registers to be saved for this record */
+  struct arm_mem_r *arm_mems;            /* memory to be saved for this record 
*/
+} arm_insn_decode_record;
+
+
+int decode_insn(arm_insn_decode_record *arm_record, uint32_t insn_size)
+{
+    union
+    {
+         uint32_t s_word;
+         gdb_byte buf[insn_size];
+    } u_buf;
+    
+    if (target_read_memory (arm_record->this_addr, &u_buf.buf[0], 
insn_size))    

+    {        
+        if (record_debug)
+            printf_unfiltered (_("Process record: error reading memory at "
+                                 "addr %s len = %d.\n"),
+            paddress (arm_record->gdbarch, arm_record->this_addr), insn_size);
+         return -1;
+    }
+    else
+    {
+        arm_record->arm_insn = u_buf.s_word;
+        arm_record->cond = ARM_PARSE_INSN (arm_record->arm_insn,29,4);
+        arm_record->id = ARM_PARSE_INSN (arm_record->arm_insn,26,3);
+
+        if (0b1111 == arm_record->cond) 
+        {
+            /* Version5 and above support this, so handle this as well.  
*/            

+        }
+        else
+        {
+            arm_handle_insn[arm_record->id]((void*)arm_record);
+        }
+    }    
+    return 0;
+}
+
+/* Parse the current instruction and record the values of the registers and
+   memory that will be changed in current instruction to "record_arch_list".
+   Return -1 if something is wrong. */
+
+int arm_process_record (struct gdbarch *gdbarch, struct regcache *regcache,
+                             CORE_ADDR insn_addr)
+{
+
+  enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);  
+  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
+  int no_of_rec=0;
+
+  union
+  {
+       uint32_t s_word;
+       gdb_byte buf[4];
+  } u_buf;
+
+  arm_insn_decode_record arm_record;
+
+  memset (&arm_record, 0, sizeof (arm_insn_decode_record));
+  arm_record.regcache = regcache;
+  arm_record.this_addr = insn_addr;
+  arm_record.gdbarch = gdbarch;
+  
+
+  if (record_debug > 1)
+    fprintf_unfiltered (gdb_stdlog, "Process record: arm_process_record "
+                        "addr = %s\n",
+            paddress (gdbarch, arm_record.this_addr));
+
+  /* check the insn, whether it is thumb or arm one */
+  GET_REG_VAL (arm_record.regcache, ARM_PS_REGNUM, &u_buf.buf[0]);
+  if (IS_IT_ARM_INSN (u_buf.s_word))
+  {
+    /* we are decoding arm insn */
+    decode_insn (&arm_record, 4);
+  }
+  else
+  {
+    /* we are decoding thumb insn */
+    decode_insn (&arm_record, 2);    
+  }
+
+  /* record registers */
+  ARM_RECORD_ARCH_LIST_ADD_REG(ARM_PC_REGNUM);
+  if(arm_record.arm_regs)
+  {
+    for(no_of_rec=1;no_of_rec<=arm_record.arm_regs[0];no_of_rec++)
+    {
+      if(ARM_RECORD_ARCH_LIST_ADD_REG(arm_record.arm_regs[no_of_rec]))
+      {
+            return -1;
+      }
+    }
+  }  
+  /* record memories */
+  if(arm_record.arm_mems)
+  {
+    for(no_of_rec=1;no_of_rec<=arm_record.arm_mems[0].len;no_of_rec++)
+    {
+      if(record_arch_list_add_mem((CORE_ADDR)arm_record.arm_mems[no_of_rec].\
+                                   addr,arm_record.arm_mems[no_of_rec].len))
+      {
+        return -1;
+      }
+    }
+  }
+  
+  if (record_arch_list_add_end ())
+  {
+      return -1;
+  }
+  return 0; 
+}
+
+int arm_handle_data_proc_misc_load_str_insn(void *data)
+{
+
+   arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
+   struct gdbarch_tdep *tdep = gdbarch_tdep ((struct gdbarch*) 
arm_insn_r->gdbarch);
+   struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
+
+   union
+   {
+     uint32_t s_word;
+     gdb_byte buf[4];
+   }u_buf[2];
+          
+   uint32_t reg_val1=0,reg_val2=0;
+   uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
+   uint32_t immed_high=0,immed_low=0,offset_8=0,tgt_mem_addr=0;
+
+   arm_insn_r->opcode = ARM_PARSE_INSN(arm_insn_r->arm_insn,22,4);
+   arm_insn_r->decode = ARM_PARSE_INSN(arm_insn_r->arm_insn,5,4);
+        
+   if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_BIT_NUM)) 
+   {
+      /* data processing insn /multiply sinsn */    
+      if(9 == arm_insn_r->decode)
+      {
+        /* handle multiply instructions */
+        /* MLA, MUL, SMLAL, SMULL, UMLAL, UMULL */
+        if((0 == arm_insn_r->opcode) || (1 == arm_insn_r->opcode))
+        {
+            /* handle MLA and MUL */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*3);
+            arm_insn_r->arm_regs[0] = 2;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            arm_insn_r->arm_regs[2] = ARM_PS_REGNUM;
+        }
+        else if((4 <= arm_insn_r->opcode) && (7 >= arm_insn_r->opcode))
+        {
+            /* handle SMLAL, SMULL, UMLAL, UMULL */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*4);
+            arm_insn_r->arm_regs[0] = 3;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            arm_insn_r->arm_regs[2] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+            arm_insn_r->arm_regs[3] = ARM_PS_REGNUM;  
+            
+        }        
+      }
+      else if((11 == arm_insn_r->decode) || (13 == arm_insn_r->decode))
+      {
+        /* handle misc load insns, as 20th bit (L = 1) */
+        /* LDR insn has a capability to do branching, if
+                  MOV LR, PC is precedded by LDR insn having Rn as R15 
+                  in that case, it emulates branch and link insn, and hence we 
+                  need to save CSPR and PC as well. */
+          reg_dest = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+          if(15 != reg_dest)
+          {
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+            arm_insn_r->arm_regs[0] = 1;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+          }
+          else
+          {
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*3);
+            arm_insn_r->arm_regs[0] = 2;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+            arm_insn_r->arm_regs[2] = ARM_PS_REGNUM; 
+          }
+      }
+      else
+      {
+        /* normal data processing insns */
+        /* out of 11 shifter operands mode, all the insn modifies destination 
+                  register, which is specified by 13-16 decode */
+        arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*3);
+        arm_insn_r->arm_regs[0] = 2;
+        arm_insn_r->arm_regs[0] = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+        arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;        
+      }
+   }
+   else
+   {
+      /* handle misc, swap insns, and store instructions as 20th bit ((L = 0) 
*/  

+      if(9 == arm_insn_r->decode)
+      {
+        /* Handling SWP, SWPB */
+        /* these insns, changes register and memory as well */
+        if((8 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode))
+        {
+            /* SWP or SWPB insn */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+            arm_mem_r)*2);
+            /* get memory address given by Rn */
+            reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4); 
+            GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);
+            arm_insn_r->arm_mems[0].len = 1;
+            /* SWP insn ?, swaps word */
+            if (8 == arm_insn_r->opcode)
+            {
+                arm_insn_r->arm_mems[1].len = 4;
+            }
+            else
+            {  
+                /* SWPB insn, swaps only byte */
+                arm_insn_r->arm_mems[1].len = 1;
+            }
+            arm_insn_r->arm_mems[1].addr = u_buf[0].s_word;
+            arm_insn_r->arm_regs[0] = 1;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);    

+         }
+      }
+      else if(3 == arm_insn_r->decode)
+      {
+          /* handle BLX, branch and link/exchange */
+          if(9 == arm_insn_r->opcode)
+          {
+              /* branch is chosen by setting T bit of CSPR, bitp[0] of Rm, 
+                             and R14 stores the return address */
+              arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*3);
+              arm_insn_r->arm_regs[0] = 2;
+              arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
+              arm_insn_r->arm_regs[2] = ARM_LR_REGNUM;
+          }
+      }
+      else if(7 == arm_insn_r->decode)
+      {
+          /* handle enhanced software breakpoint insn, BKPT */
+          /* CPSR is changed to be executed in ARM state,  disabling normal 
+                      interrupts, entering abort mode */
+          /* accorindly to high vector configuration PC is set accordingly */
+          /* Oza: FIX ME ?  what if user hit breakpoint and type reverse, in 
+                     that case, we need to go back with previous CSPR and 
+                     Program Counter. */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+            arm_insn_r->arm_regs[0] = 1;
+            arm_insn_r->arm_regs[0] = ARM_PS_REGNUM;
+      }
+      else if(13 == arm_insn_r->decode)
+      {
+          /* handle enhanced store insns and LDRD DSP insn and */
+          /* let us begin according to addressing modes for store insns */
+
+          if((14 == arm_insn_r->opcode) || (10 == arm_insn_r->opcode))
+          {
+            /* 1) handle misc store, immediate offset */
+            immed_low = ARM_PARSE_INSN(arm_insn_r->arm_insn,1,4);
+            immed_high = ARM_PARSE_INSN(arm_insn_r->arm_insn,9,4);
+            reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);            
+            if(15 == reg_src1)
+            {
+               /* if R15 was used as Rn, hence current PC+8 */
+               u_buf[0].s_word = u_buf[0].s_word + 8;
+            }            
+            offset_8 = (immed_high << 4) | immed_low;
+            /* calculate target store address */
+            if(14 == arm_insn_r->opcode)
+            {
+                tgt_mem_addr = u_buf[0].s_word + offset_8;
+            }
+            else
+            {
+                tgt_mem_addr = u_buf[0].s_word - offset_8;
+            }
+            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+            arm_mem_r)*2);
+            arm_insn_r->arm_mems[0].len = 1;
+            arm_insn_r->arm_mems[1].len = 2;
+            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
+          }
+          else if((12 == arm_insn_r->opcode) || (8 == arm_insn_r->opcode))
+          {
+            /* 2) store, register offset */
+            /* get Rm */
+            reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,1,4);  
+            /* get Rn */
+            reg_src2 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);
+            
GET_REG_VAL(reg_cache,reg_src2,&u_buf[1].buf[0]);                        

+            if(15 == reg_src2)
+            {
+               /* if R15 was used as Rn, hence current PC+8 */
+               u_buf[0].s_word = u_buf[0].s_word + 8;
+            }            
+            /* calculate target store address, Rn +/- Rm, register offset */
+            if(12 == arm_insn_r->opcode)
+            {
+                tgt_mem_addr = u_buf[0].s_word + u_buf[1].s_word;
+            }
+            else
+            {
+                tgt_mem_addr = u_buf[1].s_word - u_buf[0].s_word;
+            }            
+            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+            arm_mem_r)*2);
+            arm_insn_r->arm_mems[0].len = 1;
+            arm_insn_r->arm_mems[1].len = 2;
+            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
+          }
+          else if((11 == arm_insn_r->opcode) || (15 == arm_insn_r->opcode)
+                  || (2 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode))
+          {
+            /* 3) store, immediate pre-indexed */            
+            /* 5)  store, immediate post-indexed */
+            immed_low = ARM_PARSE_INSN(arm_insn_r->arm_insn,1,4);  
+            immed_high = ARM_PARSE_INSN(arm_insn_r->arm_insn,9,4);
+            offset_8 = (immed_high << 4) | immed_low;
+            reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);
+            /* calculate target store address, Rn +/- Rm, register offset */
+            if((15 == arm_insn_r->opcode) || (6 == arm_insn_r->opcode))
+            {
+                tgt_mem_addr = u_buf[0].s_word + offset_8;
+            }
+            else
+            {
+                tgt_mem_addr = u_buf[0].s_word - offset_8;
+            }            
+            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+            arm_mem_r)*2);
+            arm_insn_r->arm_mems[0].len = 1;
+            arm_insn_r->arm_mems[1].len = 2;
+            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
+            /* record Rn also as it changes */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+            arm_insn_r->arm_regs[0] = 1;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);  

+            
+          }
+          else if((9 == arm_insn_r->opcode) || (13 == arm_insn_r->opcode)
+                  || (0 == arm_insn_r->opcode) || (4 == arm_insn_r->opcode))
+          {
+            /* 4) store, register pre-indexed */
+            /* 6) store, register post -indexed */
+            reg_src1 = ARM_PARSE_INSN(arm_insn_r->arm_insn,1,4);  
+            reg_src2 = ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+            GET_REG_VAL(reg_cache,reg_src1,&u_buf[0].buf[0]);
+            GET_REG_VAL(reg_cache,reg_src2,&u_buf[1].buf[0]);
+            /* calculate target store address, Rn +/- Rm, register offset */
+            if((13 == arm_insn_r->opcode) || (4 == arm_insn_r->opcode))
+            {
+                tgt_mem_addr = u_buf[0].s_word + u_buf[1].s_word;
+            }
+            else
+            {
+                tgt_mem_addr = u_buf[1].s_word - u_buf[0].s_word;
+            }            
+            arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+            arm_mem_r)*2);
+            arm_insn_r->arm_mems[0].len = 1;
+            arm_insn_r->arm_mems[1].len = 2;
+            arm_insn_r->arm_mems[1].addr = tgt_mem_addr;
+            /* record Rn also as it changes */
+            arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+            arm_insn_r->arm_regs[0] = 1;
+            arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);              

+          }
+          /* DSP LDRD TBD */
+      }
+      else if(1 == arm_insn_r->decode)
+      {
+          /* handle BLX, branch and link/exchange */
+          if(2 == arm_insn_r->opcode)
+          {
+              /* branch is chosen by setting T bit of CSPR, bitp[0] of Rm */
+              arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+              arm_insn_r->arm_regs[0] = 1;
+              arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
+          }
+          else if(11 == arm_insn_r->opcode)
+          {
+              /* count leading zeros: CLZ */
+              arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+              arm_insn_r->arm_regs[0] = 1;
+              arm_insn_r->arm_regs[1] = 
ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+          }
+      }
+      else if((0 == arm_insn_r->opcode) || (4 == arm_insn_r->opcode))
+      {
+          /* handle MRS insn*/
+          arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+          arm_insn_r->arm_regs[0] = 1;
+          arm_insn_r->arm_regs[1] = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);  


+      }
+      else if ((9 == arm_insn_r->opcode) || (11 == arm_insn_r->opcode))
+      {
+           /* handle MSR insn*/
+          arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*2);
+          if (9 == arm_insn_r->opcode)
+          {
+              /*CSPR is going to be changed */
+              arm_insn_r->arm_regs[0] = 1;
+              arm_insn_r->arm_regs[1] = ARM_PS_REGNUM;
+          }    
+          else
+          {
+             /* SPSR is going to be changed */
+             /* OZA FIX ME ? how to read SPSR value ?*/
+          }
+      }  
+   }    
+   return 0;
+}
+
+int arm_handle_data_proc_imm_insn(void *data)
+{
+   arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
+   struct gdbarch_tdep *tdep = \
+                        gdbarch_tdep ((struct gdbarch*) arm_insn_r->gdbarch);
+   struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
+          
+   uint32_t reg_val1=0,reg_val2=0;
+   uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
+   uint32_t immed_high=0,immed_low=0,offset_8=0,tgt_mem_addr=0;
+
+   arm_insn_r->opcode = ARM_PARSE_INSN(arm_insn_r->arm_insn,22,4);
+   arm_insn_r->decode = ARM_PARSE_INSN(arm_insn_r->arm_insn,5,4);
+        
+   if (ARM_BIT_SET(arm_insn_r->arm_insn, INSN_S_BIT_NUM)) 
+   {
+       /* data processing insn, e.g. MOV */                
+       arm_insn_r->arm_regs = (uint32_t*)xmalloc(sizeof(uint32_t)*3);
+       arm_insn_r->arm_regs[0] = 2;
+       arm_insn_r->arm_regs[1] = ARM_PARSE_INSN(arm_insn_r->arm_insn,13,4);
+       arm_insn_r->arm_regs[2] = ARM_PS_REGNUM;      
+   }
+   return 0;
+}
+
+int arm_handle_ld_st_imm_offset_insn(void *data)
+{
+   arm_insn_decode_record *arm_insn_r = (arm_insn_decode_record*) data;
+   struct gdbarch_tdep *tdep = \
+                        gdbarch_tdep ((struct gdbarch*) arm_insn_r->gdbarch);
+   struct regcache *reg_cache = (struct regcache*) arm_insn_r->regcache;
+          
+   uint32_t reg_val1=0,reg_val2=0;
+   uint32_t reg_src1=0,reg_src2=0,reg_dest=0;
+   uint32_t immed_high=0,immed_low=0,offset_12=0,tgt_mem_addr=0;
+
+   union
+   {
+     uint32_t s_word;
+     gdb_byte buf[4];
+   }u_buf;
+
+   arm_insn_r->opcode = ARM_PARSE_INSN(arm_insn_r->arm_insn,22,4);
+   arm_insn_r->decode = ARM_PARSE_INSN(arm_insn_r->arm_insn,5,4);
+
+   /* Oza: as of now only STR is getting implemented for demo */
+   reg_src1= ARM_PARSE_INSN(arm_insn_r->arm_insn,17,4);
+   offset_12 = ARM_PARSE_INSN(arm_insn_r->arm_insn,1,12);
+   GET_REG_VAL(reg_cache,reg_src1,&u_buf.buf[0]);
+   if (ARM_BIT_SET(arm_insn_r->arm_insn,24))
+   {  
+     tgt_mem_addr =  u_buf.s_word + offset_12;
+   }
+   else
+   {
+     tgt_mem_addr =  u_buf.s_word - offset_12;
+   }
+  
+   arm_insn_r->arm_mems = (struct arm_mem_r *)xmalloc(sizeof(struct 
+                arm_mem_r)*2);
+   arm_insn_r->arm_mems[0].len = 1;
+   arm_insn_r->arm_mems[1].len = 4;
+   arm_insn_r->arm_mems[1].addr = tgt_mem_addr;      
+   return 0;
+}
+
+int arm_handle_ld_st_reg_offset_insn(void *data)
+{
+   /* TBD */
+   return 0;  
+}
+
+int arm_hamdle_ld_st_multiple_insn(void *data)
+{
+   /* TBD */
+   return 0;  
+}
+
+int arm_handle_brn_insn(void *data)
+{
+   /* TBD */
+   return 0;
+}
+
+int arm_handle_coproc_insn(void *data)
+{
+   /* TBD */
+   return 0;  
+}
+
+int arm_handle_coproc_data_proc_insn(void *data)
+{
+   /* TBD */
+   return 0;  
+}

Regards,
Oza.



----- Original Message ----
From: paawan oza <paawan1982@yahoo.com>
To: Michael Snyder <msnyder@vmware.com>
Cc: "gdb@sourceware.org" <gdb@sourceware.org>
Sent: Tue, February 1, 2011 8:50:51 AM
Subject: Re: arm reversible execution query

Hi Michael,

thank you for your reply.

I think you are referring to below line. in process_record.

I386_RECORD_ARCH_LIST_ADD_REG (X86_RECORD_REIP_REGNUM);
  if (record_arch_list_add_end ())
    return -1;


I got it that it has to be saved explicitly by process record arch level.

Thanks,
Oza.


----- Original Message ----
From: Michael Snyder <msnyder@vmware.com>
To: paawan oza <paawan1982@yahoo.com>
Cc: "gdb@sourceware.org" <gdb@sourceware.org>
Sent: Tue, February 1, 2011 12:23:14 AM
Subject: Re: arm reversible execution query

paawan oza wrote:
> 
> Hi all,
> 
> I have been wroking on arm-reversible implementation and doing arm insn part. I 
>
>
>am done with framework, and supporting 30-40% on insns till now.
> when I simply test on arm board, I find that,
> 
> all the memory and registers are replayed correctly and recording is 
happening.
> but,
> do I need to save Program counter explicitly ?
> doesnt gdb reversible framework take care of changing pc when I apply 
>reverse-stepi/nexti command ?
> 
> as i386-tdep.c, does not seem to be saving PC explicitly.
> 
> please clarify.


i386-tdep.c does save the PC ($eip), at the end of function i386_process_record.

If you don't save the PC, how can you do a reverse jump?


      


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