Merge pull request #38 from mrexodia/allocation-alignment

Align the result of memory.find_free to be suitable for allocation per default

Author: mrexodia

src/dumpulator/dumpulator.py

@@ -681,6 +681,7 @@ def call(self, addr, args: List[int] = [], regs: dict = {}, count=0):
     def allocate(self, size, page_align=False):
         if not self._allocate_ptr:
             self._allocate_base = self.memory.find_free(self._allocate_size)
+            assert self._allocate_base is not None, "Failed to find free memory"
             self.memory.reserve(
                 start=self._allocate_base,
                 size=self._allocate_size,

src/dumpulator/memory.py

@@ -152,15 +152,21 @@ def align_allocation(self, addr: int):
         mask = self._granularity - 1
         return (addr + mask) & ~mask
 
-    def find_free(self, size: int):
+    def find_free(self, size: int, allocation_align=True):
         assert size > 0 and self.align_page(size) == size
         base = self._minimum
         while base < self._maximum:
             info = self.query(base)
             assert info.base == base
-            if info.state == MemoryState.MEM_FREE and info.region_size >= size and self.align_allocation(base) == base:
-                return info.base
             base += info.region_size
+            if info.state == MemoryState.MEM_FREE:
+                if allocation_align:
+                    aligned_base = self.align_allocation(info.base)
+                    diff = aligned_base - info.base
+                    info.base = aligned_base
+                    info.region_size -= diff
+                if info.region_size >= size:
+                    return info.base
         return None
 
     def reserve(self, start: int, size: int, protect: MemoryProtect, type: MemoryType = MemoryType.MEM_PRIVATE, info: Any = None):