no segfault anymore

.gitignore

@@ -1,13 +1,16 @@
-backend/index/*
+/backend/index/*
 __pycache__
 *.code-workspace
 *.egg.info
 /src/*.egg-info/*
 /dist/*
 .vscode
+.venv
 .mypy_cache
 .pytest_cache
-tests/autogenerated_*.py
+/tests/autogenerated_*.py
 *test*.o
-/src/copapy/obj/ops*.o
 test.copapy
+token.txt
+/src/copapy/obj/*.o
+runmem2

build.sh

@@ -7,4 +7,3 @@ gcc -c src/copapy/stencils.c -o src/copapy/obj/stencils_x86_64.o
 gcc -c src/copapy/stencils.c -O1 -o src/copapy/obj/stencils_x86_64_O1.o
 gcc -c src/copapy/stencils.c -O2 -o src/copapy/obj/stencils_x86_64_O2.o
 gcc -c src/copapy/stencils.c -O3 -o src/copapy/obj/stencils_x86_64_O3.o
-ls -l src/copapy/obj/*.o

pyproject.toml

@@ -7,7 +7,7 @@ authors = [
 description = "Copy-Patch Compiler"
 readme = "README.md"
 requires-python = ">=3.10"
-license = "MIT"
+license = "GPL-3.0-only"
 classifiers = [
     "Programming Language :: Python :: 3",
     "Operating System :: OS Independent",

src/copapy/__init__.py

@@ -338,20 +338,30 @@ def compile_to_instruction_list(end_nodes: Iterable[Node] | Node) -> binw.data_w
 
     print('object_addr_lookp: ', object_addr_lookp)
 
+    data = sdb.get_func_data('function_start')
+    data_list.append(data)
+    offset += len(data)
+
     for result_net, node in extended_output_ops:
         assert node.name in sdb.function_definitions, f"- Warning: {node.name} prototype not found"
         data = sdb.get_func_data(node.name)
         data_list.append(data)
-        print('*', node.name, ' '.join(f'{d:02X}' for d in data))
+        print(f"* {node.name} ({offset}) " + ' '.join(f'{d:02X}' for d in data))
         
         for patch in sdb.get_patch_positions(node.name):
             assert result_net, f"Relocation found but no net defined for operation {node.name}"
             object_addr = object_addr_lookp[result_net]
-            print('patch: ', patch, offset + patch.addr)
-            patch_list.append((patch.type.value, offset + patch.addr, object_addr))
+            patch_value = object_addr + patch.addend - (offset + patch.addr)
+            print('patch: ', patch, object_addr, patch_value)
+            patch_list.append((patch.type.value, offset + patch.addr, patch_value))
 
         offset += len(data)
 
+    data = sdb.get_func_data('function_end')
+    data_list.append(data)
+    offset += len(data)
+    print('function_end', offset, data)
+
     # allocate program data
     dw.write_com(binw.Command.ALLOCATE_CODE)
     dw.write_int(offset)
@@ -367,7 +377,7 @@ def compile_to_instruction_list(end_nodes: Iterable[Node] | Node) -> binw.data_w
         dw.write_com(binw.Command.PATCH_OBJECT)
         dw.write_int(patch_addr)
         dw.write_int(patch_type)
-        dw.write_int(object_addr)
+        dw.write_int(object_addr, signed=True)
 
     # set entry point
     dw.write_com(binw.Command.SET_ENTR_POINT)

src/copapy/generate_stencils.py

@@ -4,6 +4,22 @@ from typing import Generator
 op_signs = {'add': '+', 'sub': '-', 'mul': '*', 'div': '/'}
 
 
+def get_function_start():
+    return """
+    void function_start(){
+        result_int(0);
+        asm volatile (".long 0xF27ECAFE");
+    }
+    """
+
+def get_function_end():
+    return """
+    void function_end(){
+        result_int(0);
+        asm volatile (".long 0xF17ECAFE");
+    }
+    """
+
 def get_op_code(op: str, type1: str, type2: str, type_out: str):
     return f"""
     void {op}_{type1}_{type2}({type1} arg1, {type2} arg2) {{
@@ -95,5 +111,7 @@ if __name__ == "__main__":
     for t1 in types:
         code += get_write_code(t1)
 
+    code += get_function_start() + get_function_end()
+
     with open('src/copapy/stencils.c', 'w') as f:
         f.write(code)

src/copapy/stencil_db.py

@@ -3,11 +3,13 @@ import pelfy
 from typing import Generator, Literal
 from enum import Enum
 
+ByteOrder = Literal['little', 'big']
 
-start_marker = 0xF17ECAFE
-end_marker = 0xF27ECAFE
+START_MARKER = 0xF17ECAFE
+END_MARKER = 0xF27ECAFE
+MARKER_LENGTH = 4
 
-LENGTH_CALL_INSTRUCTION = 4  # x86_64
+LENGTH_CALL_INSTRUCTION = 5  # x86_64
 
 RelocationType = Enum('RelocationType', [('RELOC_RELATIVE_32', 0)])
 
@@ -22,37 +24,45 @@ class patch_entry:
     
     type: RelocationType
     addr: int
+    addend: int
 
 
 def translate_relocation(relocation_addr: int, reloc_type: str, bits: int, r_addend: int) -> patch_entry:
     if reloc_type in ('R_AMD64_PLT32', 'R_AMD64_PC32'):
         # S + A - P
-        patch_offset = relocation_addr - r_addend
-        return patch_entry(RelocationType.RELOC_RELATIVE_32, patch_offset)
+        patch_offset = relocation_addr
+        return patch_entry(RelocationType.RELOC_RELATIVE_32, patch_offset, r_addend)
     else:
         raise Exception(f"Unknown: {reloc_type}")
 
 
-def get_ret_function_def(symbol: pelfy.elf_symbol):
-    #print('*', symbol.name, symbol.section)
+def get_ret_function_def(symbol: pelfy.elf_symbol) -> str:
+    #print('*', symbol.name, len(symbol.relocations))
+    if symbol.relocations:
         result_func = symbol.relocations[-1].symbol
 
         assert result_func.name.startswith('result_')
         return result_func.name[7:]
+    else:
+        return 'void'
 
 
-def strip_symbol(data: bytes, byteorder: Literal['little', 'big']) -> bytes:
+def strip_symbol(data: bytes, byteorder: ByteOrder) -> bytes:
     """Return data between start and end marker and removing last instruction (call)"""
+    start_index, end_index = get_stencil_position(data, byteorder)
+    return data[start_index:end_index]
 
+
+def get_stencil_position(data: bytes, byteorder: ByteOrder) -> tuple[int, int]:
     # Find first start marker
-    start_index = data.find(start_marker.to_bytes(4, byteorder))
+    marker_index = data.find(START_MARKER.to_bytes(MARKER_LENGTH, byteorder))
+    start_index = 0 if marker_index < 0 else marker_index + MARKER_LENGTH
 
     # Find last end marker
-    end_index = data.rfind(end_marker.to_bytes(4, byteorder), start_index)
-
-    assert start_index > -1 and end_index > -1, f"Marker not found"
-    return data[start_index + 4:end_index - LENGTH_CALL_INSTRUCTION]
+    end_index = data.rfind(END_MARKER.to_bytes(MARKER_LENGTH, byteorder))
+    end_index = len(data) if end_index < 0 else end_index - LENGTH_CALL_INSTRUCTION
 
+    return start_index, end_index
 
 
 class stencil_database():
@@ -82,8 +92,7 @@ class stencil_database():
         """Return patch positions
         """
         symbol = self.elf.symbols[symbol_name]
-        start_index = symbol.data.find(start_marker.to_bytes(4, symbol.file.byteorder))
-        end_index = symbol.data.rfind(end_marker.to_bytes(4, symbol.file.byteorder), start_index)
+        start_index, end_index = get_stencil_position(symbol.data, symbol.file.byteorder)
 
         for reloc in symbol.relocations:
             
@@ -95,7 +104,7 @@ class stencil_database():
                 reloc.fields['r_addend'])
 
             # Exclude the call to the result_x function
-            if patch.addr < end_index - start_index - LENGTH_CALL_INSTRUCTION:
+            if patch.addr < end_index - start_index:
                 yield patch
 
 

src/copapy/stencils.c

@@ -223,3 +223,13 @@
         asm volatile (".long 0xF27ECAFE");
     }
     
+    void function_start(){
+        result_int(0);
+        asm volatile (".long 0xF27ECAFE");
+    }
+    
+    void function_end(){
+        result_int(0);
+        asm volatile (".long 0xF17ECAFE");
+    }
+    

src/runner/runmem2.c

@@ -71,6 +71,7 @@ int parse_commands(uint8_t *bytes){
     int data_offs;
     uint32_t size;
     int err_flag = 0;
+    uint32_t rel_entr_point;
     
     while(!err_flag){
         command = *(uint32_t*)bytes;
@@ -78,8 +79,8 @@ int parse_commands(uint8_t *bytes){
         switch(command) {
         	case ALLOCATE_DATA:
                 size = *(uint32_t*)bytes; bytes += 4;
-                printf("ALLOCATE_DATA size=%i\n", size);
                 data_memory = get_data_memory(size);
+                printf("ALLOCATE_DATA size=%i mem_addr=%p\n", size, (void*)data_memory);
                 break;
             
         	case COPY_DATA:
@@ -91,9 +92,9 @@ int parse_commands(uint8_t *bytes){
             
         	case ALLOCATE_CODE:
                 size = *(uint32_t*)bytes; bytes += 4;
-                printf("ALLOCATE_CODE size=%i\n", size);
                 executable_memory = get_executable_memory(size);
                 executable_memory_len = size;
+                printf("ALLOCATE_CODE size=%i mem_addr=%p\n", size, (void*)executable_memory);
                 //printf("# d %i  c %i  off %i\n", data_memory, executable_memory, data_offs);
                 break;
             
@@ -117,19 +118,19 @@ int parse_commands(uint8_t *bytes){
                 offs = *(uint32_t*)bytes; bytes += 4;
                 reloc_type = *(uint32_t*)bytes; bytes += 4;
                 value = *(int32_t*)bytes; bytes += 4;
-                printf("PATCH_OBJECT patch_offs=%i reloc_type=%i value=%i\n",
-                    offs, reloc_type, value);
                 data_offs = (int32_t)(data_memory - executable_memory);
+                //printf("PATCH_OBJECT patch_offs=%i reloc_type=%i value=%i data_offs=%i\n",
+                //    offs, reloc_type, value, data_offs);
                 if (abs(data_offs) > 0x7FFFFFFF) {
                     perror("code and data memory to far apart");
                     return EXIT_FAILURE;
                 }
-                patch(executable_memory + offs, reloc_type, value + (int32_t)data_offs);
+                patch(executable_memory + offs, reloc_type, value + data_offs);
                 //printf("> %i\n", data_offs);
                 break;
             
             case SET_ENTR_POINT:
-                uint32_t rel_entr_point = *(uint32_t*)bytes; bytes += 4;
+                rel_entr_point = *(uint32_t*)bytes; bytes += 4;
                 printf("SET_ENTR_POINT rel_entr_point=%i\n", rel_entr_point);
                 entr_point = (int (*)())(executable_memory + rel_entr_point);    
                 break;

test.sh

@@ -0,0 +1,8 @@
+#!/bin/bash
+set -e
+echo "Compile..."
+python tests/test_compile.py
+echo "Run..."
+echo "-----------------------------------"
+gcc -Wall -Wextra -Wconversion -Wsign-conversion -Wshadow -Wstrict-overflow -Werror -g src/runner/runmem2.c -o runmem2
+./runmem2 test.copapy

tests/test_stencil.db.py

@@ -1,9 +1,26 @@
 from copapy import stencil_database
+from copapy import stencil_db
 
-if __name__ == "__main__":
+def test_list_symbols():
     sdb = stencil_database('src/copapy/obj/stencils_x86_64_O3.o')
     print('----')
     #print(sdb.function_definitions)
     for sym_name in sdb.function_definitions.keys():
         print('\n-', sym_name)
         print(list(sdb.get_patch_positions(sym_name)))
+
+
+def test_start_end_function():
+    sdb = stencil_database('src/copapy/obj/stencils_x86_64_O3.o')
+    for sym_name in sdb.function_definitions.keys():
+        data = sdb.elf.symbols[sym_name].data
+        print('-', sym_name, stencil_db.get_stencil_position(data, sdb.elf.byteorder), len(data))
+
+        start, end = stencil_db.get_stencil_position(data, sdb.elf.byteorder)
+
+        assert start>= 0 and end >= start and end <= len(data)
+
+
+if __name__ == "__main__":
+    test_list_symbols()
+    test_start_end_function()