GH-126910 jit_unwind: refactor EH frame generation

Author: diegorusso

Include/internal/pycore_jit_unwind.h

@@ -0,0 +1,23 @@
+#ifndef Py_CORE_JIT_UNWIND_H
+#define Py_CORE_JIT_UNWIND_H
+
+#ifdef PY_HAVE_PERF_TRAMPOLINE
+
+#include <stddef.h>
+
+/* Return the size of the generated .eh_frame data for the given encoding. */
+size_t _PyJitUnwind_EhFrameSize(int absolute_addr);
+
+/*
+ * Build DWARF .eh_frame data for JIT code; returns size written or 0 on error.
+ * absolute_addr selects the FDE address encoding:
+ * - 0: PC-relative offsets.
+ * - nonzero: absolute addresses.
+ */
+size_t _PyJitUnwind_BuildEhFrame(uint8_t *buffer, size_t buffer_size,
+                                 const void *code_addr, size_t code_size,
+                                 int absolute_addr);
+
+#endif  // PY_HAVE_PERF_TRAMPOLINE
+
+#endif  // Py_CORE_JIT_UNWIND_H

Makefile.pre.in

@@ -510,6 +510,7 @@ PYTHON_OBJS=	\
 		Python/suggestions.o \
 		Python/perf_trampoline.o \
 		Python/perf_jit_trampoline.o \
+		Python/jit_unwind.o \
 		Python/remote_debugging.o \
 		Python/$(DYNLOADFILE) \
 		$(LIBOBJS) \