Declare or define opcode metadata based on NEED_OPCODE_TABLES

Author: gvanrossum

Python/opcode_metadata.h

@@ -2,8 +2,10 @@
 // from Python/bytecodes.c
 // Do not edit!
 
-#ifndef NDEBUG
-static int
+#ifndef NEED_OPCODE_TABLES
+extern int _PyOpcode_num_popped(int opcode, int oparg, bool jump);
+#else
+int
 _PyOpcode_num_popped(int opcode, int oparg, bool jump) {
     switch(opcode) {
         case NOP:
@@ -350,8 +352,10 @@ _PyOpcode_num_popped(int opcode, int oparg, bool jump) {
 }
 #endif
 
-#ifndef NDEBUG
-static int
+#ifndef NEED_OPCODE_TABLES
+extern int _PyOpcode_num_pushed(int opcode, int oparg, bool jump);
+#else
+int
 _PyOpcode_num_pushed(int opcode, int oparg, bool jump) {
     switch(opcode) {
         case NOP:
@@ -697,6 +701,7 @@ _PyOpcode_num_pushed(int opcode, int oparg, bool jump) {
     }
 }
 #endif
+
 enum Direction { DIR_NONE, DIR_READ, DIR_WRITE };
 enum InstructionFormat { INSTR_FMT_IB, INSTR_FMT_IBC, INSTR_FMT_IBC0, INSTR_FMT_IBC000, INSTR_FMT_IBC0000, INSTR_FMT_IBC00000000, INSTR_FMT_IBIB, INSTR_FMT_IX, INSTR_FMT_IXC, INSTR_FMT_IXC000 };
 struct opcode_metadata {
@@ -705,7 +710,12 @@ struct opcode_metadata {
     enum Direction dir_op3;
     bool valid_entry;
     enum InstructionFormat instr_format;
-} _PyOpcode_opcode_metadata[256] = {
+};
+
+#ifndef NEED_OPCODE_TABLES
+extern const struct opcode_metadata _PyOpcode_opcode_metadata[256];
+#else
+const struct opcode_metadata _PyOpcode_opcode_metadata[256] = {
     [NOP] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
     [RESUME] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IB },
     [LOAD_CLOSURE] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IB },
@@ -876,3 +886,4 @@ struct opcode_metadata {
     [EXTENDED_ARG] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IB },
     [CACHE] = { DIR_NONE, DIR_NONE, DIR_NONE, true, INSTR_FMT_IX },
 };
+#endif

Tools/cases_generator/generate_cases.py

@@ -888,8 +888,11 @@ def write_stack_effect_functions(self) -> None:
         def write_function(
             direction: str, data: list[tuple[AnyInstruction, str]]
         ) -> None:
-            self.out.emit("\n#ifndef NDEBUG")
-            self.out.emit("static int")
+            self.out.emit("")
+            self.out.emit("#ifndef NEED_OPCODE_TABLES")
+            self.out.emit(f"extern int _PyOpcode_num_{direction}(int opcode, int oparg, bool jump);")
+            self.out.emit("#else")
+            self.out.emit("int")
             self.out.emit(f"_PyOpcode_num_{direction}(int opcode, int oparg, bool jump) {{")
             self.out.emit("    switch(opcode) {")
             for instr, effect in data:
@@ -903,6 +906,7 @@ def write_function(
 
         write_function("popped", popped_data)
         write_function("pushed", pushed_data)
+        self.out.emit("")
 
     def write_metadata(self) -> None:
         """Write instruction metadata to output file."""
@@ -934,7 +938,7 @@ def write_metadata(self) -> None:
 
             self.write_stack_effect_functions()
 
-            # Write variable definition
+            # Write type definitions
             self.out.emit("enum Direction { DIR_NONE, DIR_READ, DIR_WRITE };")
             self.out.emit(f"enum InstructionFormat {{ {', '.join(format_enums)} }};")
             self.out.emit("struct opcode_metadata {")
@@ -944,7 +948,14 @@ def write_metadata(self) -> None:
                 self.out.emit("enum Direction dir_op3;")
                 self.out.emit("bool valid_entry;")
                 self.out.emit("enum InstructionFormat instr_format;")
-            self.out.emit("} _PyOpcode_opcode_metadata[256] = {")
+            self.out.emit("};")
+            self.out.emit("")
+
+            # Write metadata array declaration
+            self.out.emit("#ifndef NEED_OPCODE_TABLES")
+            self.out.emit("extern const struct opcode_metadata _PyOpcode_opcode_metadata[256];")
+            self.out.emit("#else")
+            self.out.emit("const struct opcode_metadata _PyOpcode_opcode_metadata[256] = {")
 
             # Write metadata for each instruction
             for thing in self.everything:
@@ -961,6 +972,7 @@ def write_metadata(self) -> None:
 
             # Write end of array
             self.out.emit("};")
+            self.out.emit("#endif")
 
     def write_metadata_for_inst(self, instr: Instruction) -> None:
         """Write metadata for a single instruction."""