Warn about self-modifying code.

futurecore · Sep 1, 2016 · d5a026e · d5a026e
1 parent cd11c9a
commit d5a026e
Show file tree

Hide file tree

Showing 4 changed files with 38 additions and 9 deletions.
diff --git a/revelation/elf_loader.py b/revelation/elf_loader.py
@@ -10,7 +10,7 @@ def load_program(elf, mem, coreids, alignment=0, ext_base=0x8e000000,
     pydgin.elf.elf_reader().
     """
     sections   = elf.get_sections()
-    entrypoint = -1
+    code_blocks = []
     for coreid in coreids:
         coreid_mask = coreid << 20
         for section in sections:
@@ -20,9 +20,10 @@ def load_program(elf, mem, coreids, alignment=0, ext_base=0x8e000000,
                 start_addr = section.addr
             for index, data in enumerate(section.data):
                 mem.write(start_addr + index, 1, ord(data), quiet=True)
-            if section.name == '.text':
-                entrypoint = intmask(section.addr)
+            if section.name == '.text' or section.name == 'NEW_LIB_RO':
+                entry_point = intmask(start_addr)
+                end_point = entry_point + len(section.data)
+                code_blocks.append((entry_point, end_point))
             if section.name == '.data':
                 mem.data_section = section.addr
-    assert entrypoint >= 0
-    return
+    return code_blocks
diff --git a/revelation/sim.py b/revelation/sim.py
@@ -289,8 +289,10 @@ def init_state(self, elf_file, filename, testbin, is_test=False):
                         zfill(str(f_col + col), 2)))
                 self.states[coreid] = State(self.memory, self.debug,
                                             logger=self.logger, coreid=coreid)
-        load_program(elf, self.memory, coreids, ext_base=self.ext_base,
-                     ext_size=self.ext_size)
+        code_blocks = load_program(elf, self.memory, coreids, ext_base=self.ext_base,
+                                   ext_size=self.ext_size)
+        for section in code_blocks:
+            self.memory.code_blocks.append(section)
         self.states[coreids[0]].set_first_core(True)
         if self.profile:
             timer = time.time()

diff --git a/revelation/storage.py b/revelation/storage.py
@@ -59,6 +59,7 @@ def __init__(self, block_size=2**20, logger=None):
         self.addr_mask  = block_size - 1
         self.block_mask = 0xffffffff ^ self.addr_mask
         self.block_dict = {}
+        self.code_blocks = []
 
     def add_block(self, block_addr):
         self.block_dict[block_addr] = _BlockMemory(size=self.block_size)
@@ -118,6 +119,9 @@ def write(self, start_addr, num_bytes, value, from_core=0x808, quiet=False):
         if is_local_address(start_addr):
             start_addr |= (from_core << 20)
         coreid_mask = start_addr & 0xfff00000
+        for start, end in self.code_blocks:
+            if start_addr >= start and (start_addr + num_bytes) <= end:
+                print 'WARNING: self-modifying code @', pad_hex(start_addr)
         if start_addr & 0xfffff == 0xf042c:  # ILATST
             ilat = self.read(coreid_mask | 0xf0428, 4) & 0x3ff
             ilat |= (value & ((2 << 10) - 1))

diff --git a/revelation/test/test_compiled_c.py b/revelation/test/test_compiled_c.py
@@ -55,8 +55,30 @@
      ('print_large_float.elf',  'd     = 1.84467440737095516e+19\n'
                                 'd - 1 = 1.84467440737095516e+19\n'),
      ('read_file.elf',          'Hello, world!\n'),
-     ('selfmod.elf',            'Hello\nWorld\n'),
-     ('selfmod2.elf',           'Hello\nWorld\n'),
+     ('selfmod.elf',            'Hello\n'
+                                'WARNING: self-modifying code @ 80800350\n'
+                                'WARNING: self-modifying code @ 80800354\n'
+                                'WARNING: self-modifying code @ 80800358\n'
+                                'WARNING: self-modifying code @ 8080035c\n'
+                                'WARNING: self-modifying code @ 80800360\n'
+                                'WARNING: self-modifying code @ 80800364\n'
+                                'WARNING: self-modifying code @ 80800368\n'
+                                'WARNING: self-modifying code @ 8080036c\n'
+                                'WARNING: self-modifying code @ 80800370\n'
+                                'WARNING: self-modifying code @ 80800374\n'
+                                'World\n'),
+     ('selfmod2.elf',           'Hello\n'
+                                'WARNING: self-modifying code @ 80800350\n'
+                                'WARNING: self-modifying code @ 80800354\n'
+                                'WARNING: self-modifying code @ 80800358\n'
+                                'WARNING: self-modifying code @ 8080035c\n'
+                                'WARNING: self-modifying code @ 80800360\n'
+                                'WARNING: self-modifying code @ 80800364\n'
+                                'WARNING: self-modifying code @ 80800368\n'
+                                'WARNING: self-modifying code @ 8080036c\n'
+                                'WARNING: self-modifying code @ 80800370\n'
+                                'WARNING: self-modifying code @ 80800374\n'
+                                'World\n'),
      ('setilat.elf',            'User interrupt set by ILATST.\n'),
      ('testset.elf',            'Before testset:\na: 0\tb: 1\n'
                                 'After testset:\na: 10\tb: 1\n'