introduce parent frame

framework/common.cpp

@@ -121,14 +121,14 @@ uint32_t __pst_context::print_expr_block (Dwarf_Op *exprs, int len, char* buff,
 	            int32_t off = decode_sleb128((unsigned char*)&exprs[i].number);
 				int regno = map->op_num - DW_OP_breg0;
 				unw_word_t ptr = 0;
-				unw_get_reg(&cursor, regno, &ptr);
+				unw_get_reg(&curr_frame, regno, &ptr);
 				//ptr += off;
 
 				offset += snprintf(buff + offset, buff_size - offset, "%s(*%s%s%d) reg_value: 0x%lX", map->op_name, unw_regname(regno), off >=0 ? "+" : "", off, ptr);
 			} else if(map->op_num >= DW_OP_reg0 && map->op_num <= DW_OP_reg16) {
 				unw_word_t value = 0;
 				int regno = map->op_num - DW_OP_reg0;
-				unw_get_reg(&cursor, regno, &value);
+				unw_get_reg(&curr_frame, regno, &value);
 				offset += snprintf(buff + offset, buff_size - offset, "%s(*%s) value: 0x%lX", map->op_name, unw_regname(regno), value);
 			} else if(map->op_num == DW_OP_GNU_entry_value) {
 				uint32_t value = decode_uleb128((unsigned char*)&exprs[i].number);
@@ -155,14 +155,14 @@ uint32_t __pst_context::print_expr_block (Dwarf_Op *exprs, int len, char* buff,
 	            uint32_t regno = decode_uleb128((unsigned char*)&exprs[i].number);
 				int32_t off = decode_sleb128((unsigned char*)&exprs[i].number2);
 				unw_word_t ptr = 0;
-				unw_get_reg(&cursor, regno, &ptr);
+				unw_get_reg(&curr_frame, regno, &ptr);
 				//ptr += off;
 				offset += snprintf(buff + offset, buff_size - offset, "%s(%s%s%d) reg_value = 0x%lX", map->op_name, unw_regname(regno), off >= 0 ? "+" : "", off, ptr);
 			} else if(map->op_num == DW_OP_regx) {
 			    int32_t reg = decode_sleb128((unsigned char*)&exprs[i].number);
 
 				unw_word_t value = 0;
-				unw_get_reg(&cursor, reg, &value);
+				unw_get_reg(&curr_frame, reg, &value);
 
 				offset += snprintf(buff + offset, buff_size - offset, "%s(%s) value = 0x%lX", map->op_name, unw_regname(reg), value);
 			} else if(map->op_num == DW_OP_addr) {

framework/common.h

@@ -14,6 +14,7 @@ typedef struct __pst_context {
 		offset = 0;
 		buff[0] = 0;
 		base_addr = 0;
+		has_nframe = false;
 	}
 
 	bool print(const char* fmt, ...);
@@ -22,7 +23,9 @@ typedef struct __pst_context {
 
 	ucontext_t*					hcontext;	// context of signal handler
 	unw_context_t				context;	// context of stack trace
-	unw_cursor_t				cursor;		// currently examined frame of context
+	unw_cursor_t				curr_frame;	// currently examined frame of context
+	unw_cursor_t                next_frame; // caller frame
+	bool                        has_nframe;	// has next frame or not
 	Dwarf_Addr					base_addr;	// base address where process loaded
 
 	char						buff[8192]; // stack trace buffer

framework/dwarf_operations.cpp

@@ -785,7 +785,7 @@ bool dw_op_breg_x(dwarf_stack* stack, const dwarf_op_map* map, Dwarf_Word op1, D
 	}
 
 	unw_word_t val = 0;
-	if(unw_get_reg(&stack->ctx->cursor, regno, &val)) {
+	if(unw_get_reg(&stack->ctx->curr_frame, regno, &val)) {
 		return false;
 	}
 
@@ -829,7 +829,7 @@ bool dw_op_call_frame_cfa(dwarf_stack* stack, const dwarf_op_map* map, Dwarf_Wor
 {
     // since in signal handler we are know SP value, just push it to DWARF stack
     unw_word_t sp;
-    if(unw_get_reg(&stack->ctx->cursor, UNW_REG_SP, &sp)) {
+    if(unw_get_reg(&stack->ctx->curr_frame, UNW_REG_SP, &sp)) {
         return false;
     }
 
@@ -844,7 +844,7 @@ bool dw_op_fbreg(dwarf_stack* stack, const dwarf_op_map* map, Dwarf_Word op1, Dw
 {
     // since in signal handler we are know SP value, just use it as DW_AT_frame_base
     unw_word_t sp;
-    if(unw_get_reg(&stack->ctx->cursor, UNW_REG_SP, &sp)) {
+    if(unw_get_reg(&stack->ctx->curr_frame, UNW_REG_SP, &sp)) {
         return false;
     }
 
@@ -1067,7 +1067,7 @@ bool __dwarf_stack::get_value(uint64_t& value)
     if(v->type & DWARF_TYPE_REGISTER_LOC) {
         // dereference register location
         uint64_t regno = value;
-        if(unw_get_reg(&ctx->cursor, regno, &value)) {
+        if(unw_get_reg(&ctx->curr_frame, regno, &value)) {
             ctx->log(SEVERITY_ERROR, "Failed to get value of register 0x%lX", regno);
             return false;
         }
@@ -1091,7 +1091,7 @@ bool __dwarf_stack::calc_expression(Dwarf_Op *exprs, int expr_len, Dwarf_Attribu
         if(v && (v->type & DWARF_TYPE_REGISTER_LOC)) {
             unw_word_t value = 0;
             uint64_t regno = *((uint64_t*)v->value);
-            if(unw_get_reg(&ctx->cursor, regno, &value)) {
+            if(unw_get_reg(&ctx->curr_frame, regno, &value)) {
                 ctx->log(SEVERITY_ERROR, "Failed to ger value of register 0x%lX", regno);
                 return false;
             }
@@ -1107,8 +1107,6 @@ bool __dwarf_stack::calc_expression(Dwarf_Op *exprs, int expr_len, Dwarf_Attribu
                 Dwarf_Op *expr;
                 size_t exprlen;
                 if (dwarf_getlocation(&attr_mem, &expr, &exprlen) == 0) {
-                    //offset += print_expr_block (expr, exprlen, buff + offset, buff_size - offset, &attr_mem);
-                    //offset += snprintf(buff + offset, buff_size - offset, ") ");
                     if(!calc_expression(expr, exprlen, &attr_mem)) {
                         ctx->log(SEVERITY_ERROR, "Failed to calculate sub-expression for operation %s(0x%lX, 0x%lX)", map->op_name, exprs[i].number, exprs[i].number2);
                         return false;

framework/sysutils.cpp

@@ -301,7 +301,7 @@ bool __pst_parameter::handle_dwarf(Dwarf_Die* result)
 	    // determine location of parameter in stack/heap or CPU registers
 	    attr = dwarf_attr(result, DW_AT_location, &attr_mem);
 	    Dwarf_Addr pc;
-	    unw_get_reg(&ctx->cursor, UNW_REG_IP,  &pc);
+	    unw_get_reg(&ctx->curr_frame, UNW_REG_IP,  &pc);
 
 	    dwarf_stack stack(ctx);
 	    char str[1024];
@@ -453,7 +453,7 @@ bool __pst_function::print_dwarf()
 bool __pst_function::handle_dwarf(Dwarf_Die* d)
 {
 	die = d;
-	ctx->cursor = cursor;
+	ctx->curr_frame = cursor;
 
 	Dwarf_Attribute attr_mem;
 	Dwarf_Attribute* attr;
@@ -792,6 +792,13 @@ pst_function* __pst_handler::next_function(pst_function* f)
 bool __pst_handler::handle_dwarf()
 {
     for(pst_function* fun = next_function(NULL); fun; fun = next_function(fun)) {
+        ctx.curr_frame = fun->cursor;
+        if(fun->parent) {
+            ctx.next_frame = fun->parent->cursor;
+            ctx.has_nframe = true;
+        } else {
+            ctx.has_nframe = false;
+        }
         get_dwarf_function(fun);
     }
 
@@ -858,9 +865,9 @@ bool __pst_handler::unwind()
     unw_word_t  	pc;
 
     unw_getcontext(&ctx.context);
-    unw_init_local(&ctx.cursor, &ctx.context);
+    unw_init_local(&ctx.curr_frame, &ctx.context);
-    while (unw_step(&ctx.cursor) > 0) {
+    while (unw_step(&ctx.curr_frame) > 0) {
-    	unw_get_reg(&ctx.cursor, UNW_REG_IP,  &pc);
+    	unw_get_reg(&ctx.curr_frame, UNW_REG_IP,  &pc);
     	if(pc == (uint64_t)caller) {
     		break;
     	} else {
@@ -887,8 +894,9 @@ bool __pst_handler::unwind()
     	ctx.print("[%-2d] ", idx);
     	Dwarf_Addr addr = (uintptr_t)array[i];
 #else
+   ctx.has_nframe = false;
    for (int i = skipped, idx = 0; true ; ++i, ++idx) {
-   		unw_get_reg(&ctx.cursor, UNW_REG_IP,  &pc);
+   		unw_get_reg(&ctx.curr_frame, UNW_REG_IP,  &pc);
    		addr = pc;
    		ctx.print("[%-2d] ", idx);
 #endif
@@ -900,7 +908,7 @@ bool __pst_handler::unwind()
    		}
    		ctx.print("\n");
 #ifdef USE_LIBUNWIND
-   		if(unw_step(&ctx.cursor) <= 0) {
+   		if(unw_step(&ctx.curr_frame) <= 0) {
    			break;
    		}
 #endif

framework/sysutils.h

@@ -88,7 +88,7 @@ typedef struct __pst_function : public SC_ListNode {
 		lowpc = 0;
 		highpc = 0;
 		parent = NULL;
-		cursor = _ctx->cursor;
+		cursor = _ctx->curr_frame;
 		parent = _parent;
 	}