Handle S_BLOCK32 in cvdump symbols parser (#1012)

tools/isledecomp/isledecomp/cvdump/symbols.py

@@ -88,6 +88,10 @@ class CvdumpSymbolsParser:
     def __init__(self):
         self.symbols: list[SymbolsEntry] = []
         self.current_function: Optional[SymbolsEntry] = None
+        # If we read an S_BLOCK32 node, increment this level.
+        # This is so we do not end the proc early by reading an S_END
+        # that indicates the end of the block.
+        self.block_level: int = 0
 
     def read_line(self, line: str):
         if (match := self._symbol_line_generic_regex.match(line)) is not None:
@@ -145,8 +149,14 @@ class CvdumpSymbolsParser:
             )
             self.current_function.stack_symbols.append(new_symbol)
 
+        elif symbol_type == "S_BLOCK32":
+            self.block_level += 1
         elif symbol_type == "S_END":
-            self.current_function = None
+            if self.block_level > 0:
+                self.block_level -= 1
+                assert self.block_level >= 0
+            else:
+                self.current_function = None
         elif symbol_type in self._unhandled_symbols:
             return
         else:

tools/isledecomp/tests/test_cvdump_symbols.py

@@ -0,0 +1,38 @@
+"""Test Cvdump SYMBOLS parser, reading function stack/params"""
+
+from isledecomp.cvdump.symbols import CvdumpSymbolsParser
+
+PROC_WITH_BLOC = """
+(000638) S_GPROC32: [0001:000C6135], Cb: 00000361, Type:             0x10ED, RegistrationBook::ReadyWorld
+         Parent: 00000000, End: 00000760, Next: 00000000
+         Debug start: 0000000C, Debug end: 0000035C
+         Flags: Frame Ptr Present
+(00067C)  S_BPREL32: [FFFFFFD0], Type:             0x10EC, this
+(000690)  S_BPREL32: [FFFFFFDC], Type:             0x10F5, checkmarkBuffer
+(0006AC)  S_BPREL32: [FFFFFFE8], Type:             0x10F6, letterBuffer
+(0006C8)  S_BPREL32: [FFFFFFF4], Type:      T_SHORT(0011), i
+(0006D8)  S_BPREL32: [FFFFFFF8], Type:             0x10F8, players
+(0006EC)  S_BPREL32: [FFFFFFFC], Type:             0x1044, gameState
+(000704)  S_BLOCK32: [0001:000C624F], Cb: 000001DA,
+          Parent: 00000638, End: 0000072C
+(00071C)   S_BPREL32: [FFFFFFD8], Type:      T_SHORT(0011), j
+(00072C)  S_END
+(000730)  S_BLOCK32: [0001:000C6448], Cb: 00000032,
+          Parent: 00000638, End: 0000075C
+(000748)   S_BPREL32: [FFFFFFD4], Type:             0x10FA, infoman
+(00075C)  S_END
+(000760) S_END
+"""
+
+
+def test_sblock32():
+    """S_END has double duty as marking the end of a function (S_GPROC32)
+    and a scope block (S_BLOCK32). Make sure we can distinguish between
+    the two and not end a function early."""
+    parser = CvdumpSymbolsParser()
+    for line in PROC_WITH_BLOC.split("\n"):
+        parser.read_line(line)
+
+    # Make sure we can read the proc and all its stack references
+    assert len(parser.symbols) == 1
+    assert len(parser.symbols[0].stack_symbols) == 8