cpython/Include/internal/pycore_jit_unwind.h
Diego Russo c7b7ca2cd5
GH-126910: Add gdb support for unwinding JIT frames (#146071)
Co-authored-by: Pablo Galindo Salgado <pablogsal@gmail.com>
2026-05-02 13:42:03 +00:00

68 lines
2 KiB
C

#ifndef Py_INTERNAL_JIT_UNWIND_H
#define Py_INTERNAL_JIT_UNWIND_H
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
#include <stddef.h>
#include <stdint.h>
#if defined(_Py_JIT) && defined(__linux__) && defined(__ELF__)
# define PY_HAVE_JIT_GDB_UNWIND
#endif
#if defined(PY_HAVE_PERF_TRAMPOLINE) || defined(PY_HAVE_JIT_GDB_UNWIND)
#if defined(PY_HAVE_JIT_GDB_UNWIND)
extern PyMutex _Py_jit_debug_mutex;
#endif
/* DWARF exception-handling pointer encodings shared by JIT unwind users. */
enum {
DWRF_EH_PE_absptr = 0x00,
DWRF_EH_PE_omit = 0xff,
/* Data type encodings */
DWRF_EH_PE_uleb128 = 0x01,
DWRF_EH_PE_udata2 = 0x02,
DWRF_EH_PE_udata4 = 0x03,
DWRF_EH_PE_udata8 = 0x04,
DWRF_EH_PE_sleb128 = 0x09,
DWRF_EH_PE_sdata2 = 0x0a,
DWRF_EH_PE_sdata4 = 0x0b,
DWRF_EH_PE_sdata8 = 0x0c,
DWRF_EH_PE_signed = 0x08,
/* Reference type encodings */
DWRF_EH_PE_pcrel = 0x10,
DWRF_EH_PE_textrel = 0x20,
DWRF_EH_PE_datarel = 0x30,
DWRF_EH_PE_funcrel = 0x40,
DWRF_EH_PE_aligned = 0x50,
DWRF_EH_PE_indirect = 0x80
};
/* 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 (perf jitdump synthesized DSO).
* - nonzero: absolute addresses (GDB JIT in-memory ELF).
*/
size_t _PyJitUnwind_BuildEhFrame(uint8_t *buffer, size_t buffer_size,
const void *code_addr, size_t code_size,
int absolute_addr);
void *_PyJitUnwind_GdbRegisterCode(const void *code_addr,
size_t code_size,
const char *entry,
const char *filename);
void _PyJitUnwind_GdbUnregisterCode(void *handle);
#endif // defined(PY_HAVE_PERF_TRAMPOLINE) || defined(PY_HAVE_JIT_GDB_UNWIND)
#endif // Py_INTERNAL_JIT_UNWIND_H