global refactoring: use libunwind to get stack frame, get rid on process

base address, better DWARF DW_OP_XXX handling, initial implementation of parameter's values retrieval
2020-01-09 18:49:45 +04:00
parent 83fc2bc3ef
commit 8f7fed23dc
6 changed files with 652 additions and 301 deletions
@@ -0,0 +1,105 @@
+/*
+ * common.cpp
+ *
+ *  Created on: Jan 8, 2020
+ *      Author: nnosov
+ */
+
+#include <inttypes.h>
+#include <stddef.h>
+
+#include "common.h"
+
+dwarf_op_map dw_op[] = {
+		{0x23, 0x0,  0, "DW_OP_plus_uconst"},
+		// Register location descriptions. From DWARF 5, section 2.6.1.1.3:
+		// Register location descriptions describe an object (or a piece of an object) that resides in a register.
+		// A register location description must stand alone as the entire description of an object or a piece of an object.
+		{0x50, 0x0,  "RAX", "DW_OP_reg0"},
+		{0x51, 0x1,  "RDX", "DW_OP_reg1"},
+		{0x52, 0x2,  "RCX", "DW_OP_reg2"},
+		{0x53, 0x3,  "RBX", "DW_OP_reg3"},
+		{0x54, 0x4,  "RSI", "DW_OP_reg4"},
+		{0x55, 0x5,  "RDI", "DW_OP_reg5"},
+		{0x56, 0x6,  "RBP", "DW_OP_reg6"},
+		{0x57, 0x7,  "RSP", "DW_OP_reg7"},
+		{0x58, 0x8,  "R8",  "DW_OP_reg8"},
+		{0x59, 0x9,  "R9",  "DW_OP_reg9"},
+		{0x5A, 0xA,  "R10", "DW_OP_reg10"},
+		{0x5B, 0xB,  "R11", "DW_OP_reg11"},
+		{0x5C, 0xC,  "R12", "DW_OP_reg12"},
+		{0x5D, 0xD,  "R13", "DW_OP_reg13"},
+		{0x5E, 0xE,  "R14", "DW_OP_reg14"},
+		{0x5F, 0xF,  "R15", "DW_OP_reg15"},
+		{0x60, 0x10, "RIP", "DW_OP_reg16"},
+
+		// Register values. DWARF5, section 2.5.1.2
+		// Register values are used to describe an object (or a piece of an object) that is located in memory at an address that is contained in
+		// a register (possibly offset by some constant)
+		{0x70, 0x0,  "RAX", "DW_OP_breg0"},
+		{0x71, 0x1,  "RDX", "DW_OP_breg1"},
+		{0x72, 0x2,  "RCX", "DW_OP_breg2"},
+		{0x73, 0x3,  "RBX", "DW_OP_breg3"},
+		{0x74, 0x4,  "RSI", "DW_OP_breg4"},
+		{0x75, 0x5,  "RDI", "DW_OP_breg5"},
+		{0x76, 0x6,  "RBP", "DW_OP_breg6"},
+		{0x77, 0x7,  "RSP", "DW_OP_breg7"},
+		{0x78, 0x8,  "R8",  "DW_OP_breg8"},
+		{0x79, 0x9,  "R9",  "DW_OP_breg9"},
+		{0x7A, 0xA,  "R10", "DW_OP_breg10"},
+		{0x7B, 0xB,  "R11", "DW_OP_breg11"},
+		{0x7C, 0xC,  "R12", "DW_OP_breg12"},
+		{0x7D, 0xD,  "R13", "DW_OP_breg13"},
+		{0x7E, 0xE,  "R14", "DW_OP_breg14"},
+		{0x7F, 0xF,  "R15", "DW_OP_breg15"},
+		{0x80, 0x10, "RIP", "DW_OP_breg16"},
+
+		// The DW_OP_fbreg operation provides a signed LEB128 offset from the address specified by the location description in the DW_AT_frame_base
+		// attribute of the current function. This is typically a stack pointer register plus or minus some offset
+		{0x91, -1,   "",     "DW_OP_fbreg"},
+		{0x92, -1,   "",     "DW_OP_bregx"},
+		{0x9C, -1,   "",     "DW_OP_call_frame_cfa"},
+		// DWARF5, Section 2.6.1.1.4:
+		// he DW_OP_stack_value operation specifies that the object does not exist in memory but its value is nonetheless known and is at the top of the DWARF
+		// expression stack. In this form of location description, the DWARF expression represents the actual value of the object, rather than its location.
+		// The DW_OP_stack_value operation terminates the expression.
+		{0x9F, -1,   "",     "DW_OP_stack_value"},
+		//
+		{0xF3, -1,   "",     "DW_OP_GNU_entry_value"},
+};
+
+const dwarf_op_map* find_op_map(int op)
+{
+	for(uint32_t i = 0; i < sizeof(dw_op) / sizeof(dwarf_op_map); ++i) {
+		if(dw_op[i].op_num == op) {
+			return &dw_op[i];
+		}
+	}
+
+	return NULL;
+}
+
+int32_t decode_sleb128(uint8_t *sleb128)
+{
+	int32_t num = 0, shift = 0, size = 0;
+	do {
+		num |= ((*sleb128 & 0x7f) << shift);
+		shift += 7;
+		size += 8;
+	} while(*sleb128++ & 0x80);
+	if((shift < size) && (*(--sleb128) & 0x40)) {
+		num |= - (1 << shift);
+	}
+	return num;
+}
+
+uint32_t decode_uleb128(uint8_t *uleb128)
+{
+	uint32_t num = 0, shift = 0;
+	do {
+		num |= ((*uleb128 & 0x7f) << shift);
+		shift += 7;
+	} while(*uleb128++ & 0x80);
+	return num;
+}
+