Add autoconf magic

Author: tiran

Include/internal/pycore_ceval.h

@@ -27,8 +27,10 @@ struct _ceval_runtime_state;
 #include "pycore_pystate.h"       // _PyThreadState_GET()
 #include "pycore_frame.h"       // _PyThreadState_GET()
 
+#ifdef HAVE_PERF_TRAMPOLINE
 typedef PyObject* (*py_evaluator)(PyThreadState *, _PyInterpreterFrame *, int throwflag);
 typedef PyObject* (*py_trampoline)(py_evaluator, PyThreadState *, _PyInterpreterFrame *, int throwflag);
+#endif
 
 extern void _Py_FinishPendingCalls(PyThreadState *tstate);
 extern void _PyEval_InitRuntimeState(struct _ceval_runtime_state *);
@@ -74,11 +76,13 @@ _PyEval_EvalFrame(PyThreadState *tstate, struct _PyInterpreterFrame *frame, int
 {
     EVAL_CALL_STAT_INC(EVAL_CALL_TOTAL);
     if (tstate->interp->eval_frame == NULL) {
+#ifdef HAVE_PERF_TRAMPOLINE
         PyCodeObject *co = frame->f_code;
         py_trampoline f = (py_trampoline)(co->co_trampoline);
         if (f) {
             return f(_PyEval_EvalFrameDefault, tstate, frame, throwflag);
         }
+#endif
         return _PyEval_EvalFrameDefault(tstate, frame, throwflag);
     }
     return tstate->interp->eval_frame(tstate, frame, throwflag);

Makefile.pre.in

@@ -443,7 +443,6 @@ OBJECT_OBJS=	\
 		Objects/cellobject.o \
 		Objects/classobject.o \
 		Objects/codeobject.o \
-		Objects/asm_trampoline.o \
 		Objects/complexobject.o \
 		Objects/descrobject.o \
 		Objects/enumobject.o \
@@ -476,7 +475,8 @@ OBJECT_OBJS=	\
 		Objects/unicodeobject.o \
 		Objects/unicodectype.o \
 		Objects/unionobject.o \
-		Objects/weakrefobject.o
+		Objects/weakrefobject.o \
+		@PERF_TRAMPOLINE_OBJ@
 
 DEEPFREEZE_OBJS = Python/deepfreeze/deepfreeze.o
 
@@ -2319,6 +2319,9 @@ config.status:	$(srcdir)/configure
 
 .PRECIOUS: config.status $(BUILDPYTHON) Makefile Makefile.pre
 
+Objects/asm_trampoline.o: $(srcdir)/Objects/asm_trampoline.sx
+	$(CC) -c $(PY_CORE_CFLAGS) -o $@ $<
+
 # Some make's put the object file in the current directory
 .c.o:
 	$(CC) -c $(PY_CORE_CFLAGS) -o $@ $<

Objects/asm_trampoline.s renamed to Objects/asm_trampoline.sx

@@ -1,6 +1,7 @@
     .text
     .globl	_Py_trampoline_func_start
 _Py_trampoline_func_start:
+#ifdef __x86_64__
     push   %rbp
     mov    %rsp,%rbp
     mov    %rdi,%rax
@@ -10,5 +11,9 @@ _Py_trampoline_func_start:
     call   *%rax
     pop    %rbp
     ret
+#endif // __x86_64__
+#ifdef __aarch64__
+    TODO
+#endif
     .globl	_Py_trampoline_func_end
 _Py_trampoline_func_end:

Objects/codeobject.c

@@ -300,12 +300,13 @@ _PyCode_Validate(struct _PyCodeConstructor *con)
     return 0;
 }
 
+#ifdef HAVE_PERF_TRAMPOLINE
 extern void* _Py_trampoline_func_start;
 extern void* _Py_trampoline_func_end;
 
 py_trampoline compile_trampoline(void) {
   char *memory = mmap(NULL,             // address
-                      4096,             // size
+                      PAGESIZE,         // size
                       PROT_READ | PROT_WRITE | PROT_EXEC,
                       MAP_PRIVATE | MAP_ANONYMOUS,
                       -1,               // fd (not used here)
@@ -347,6 +348,7 @@ void perf_map_write_entry(FILE *method_file, const void* code_addr, unsigned int
 }
 
 typedef PyObject* (*py_evaluator)(PyThreadState *, _PyInterpreterFrame *, int throwflag);
+#endif
 
 static void
 init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
@@ -363,6 +365,7 @@ init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
     Py_INCREF(con->qualname);
     co->co_qualname = con->qualname;
 
+#ifdef HAVE_PERF_TRAMPOLINE
     py_trampoline f = compile_trampoline();
     FILE* pfile = perf_map_open(getpid());
     perf_map_write_entry(pfile, f, 4096,
@@ -371,6 +374,7 @@ init_code(PyCodeObject *co, struct _PyCodeConstructor *con)
     perf_map_close(pfile);
 
     co->co_trampoline = f;
+#endif
     co->co_flags = con->flags;
 
     co->co_firstlineno = con->firstlineno;

configure

@@ -3425,6 +3425,20 @@ case "$ac_sys_system" in
 esac
 AC_MSG_RESULT($SHLIBS)
 
+dnl perf trampoline is Linux specific and requires an arch-specific
+dnl trampoline in asssembly.
+AC_MSG_CHECKING([perf trampoline])
+AS_CASE([$host],
+  [x86_64-*-linux-*], [perf_trampoline=yes],
+  [perf_trampoline=no]
+)
+AC_MSG_RESULT([$perf_trampoline])
+
+AS_VAR_IF([perf_trampoline], [yes], [
+  AC_DEFINE([HAVE_PERF_TRAMPOLINE], [1], [Define to 1 if you have the perf trampoline.])
+  PERF_TRAMPOLINE_OBJ=Objects/asm_trampoline.o
+])
+AC_SUBST([PERF_TRAMPOLINE_OBJ])
 
 # checks for libraries
 AC_CHECK_LIB(sendfile, sendfile)

configure.ac

@@ -872,6 +872,9 @@
 /* Define to 1 if you have the `pause' function. */
 #undef HAVE_PAUSE
 
+/* Define to 1 if you have the perf trampoline. */
+#undef HAVE_PERF_TRAMPOLINE
+
 /* Define to 1 if you have the `pipe' function. */
 #undef HAVE_PIPE