jit: fix ICE on BUILT_IN_TRAP [PR99126]

gcc/jit/ChangeLog:
	PR jit/99126
	* jit-builtins.c
	(gcc::jit::builtins_manager::get_builtin_function_by_id):
	Update assertion to reject BUILT_IN_NONE.
	(gcc::jit::builtins_manager::ensure_optimization_builtins_exist):
	New.
	* jit-builtins.h
	(gcc::jit::builtins_manager::ensure_optimization_builtins_exist):
	New decl.
	* jit-playback.c (gcc::jit::playback::context::replay): Call it.
	Remove redundant conditional on bm.

gcc/testsuite/ChangeLog:
	PR jit/99126
	* jit.dg/test-trap.c: New test.

gcc/jit/jit-builtins.c

@@ -162,7 +162,7 @@ builtins_manager::get_builtin_function (const char *name)
 recording::function *
 builtins_manager::get_builtin_function_by_id (enum built_in_function builtin_id)
 {
-  gcc_assert (builtin_id >= 0);
+  gcc_assert (builtin_id > BUILT_IN_NONE);
   gcc_assert (builtin_id < END_BUILTINS);
 
   /* Lazily build the functions, caching them so that repeated calls for
@@ -600,6 +600,18 @@ builtins_manager::make_ptr_type (enum jit_builtin_type,
   return base_type->get_pointer ();
 }
 
+/* Ensure that builtins that could be needed during optimization
+   get created ahead of time.  */
+
+void
+builtins_manager::ensure_optimization_builtins_exist ()
+{
+  /* build_common_builtin_nodes does most of this, but not all.
+     We can't loop through all of the builtin_data array, we don't
+     support all types yet.  */
+  (void)get_builtin_function_by_id (BUILT_IN_TRAP);
+}
+
 /* Playback support.  */
 
 /* A builtins_manager is associated with a recording::context

gcc/jit/jit-builtins.h

@@ -127,6 +127,9 @@ public:
   tree
   get_attrs_tree (enum built_in_attribute attr);
 
+  void
+  ensure_optimization_builtins_exist ();
+
   void
   finish_playback (void);
 

gcc/jit/jit-playback.c

@@ -2949,6 +2949,11 @@ replay ()
   /* Replay the recorded events:  */
   timevar_push (TV_JIT_REPLAY);
 
+  /* Ensure that builtins that could be needed during optimization
+     get created ahead of time.  */
+  builtins_manager *bm = m_recording_ctxt->get_builtins_manager ();
+  bm->ensure_optimization_builtins_exist ();
+
   m_recording_ctxt->replay_into (this);
 
   /* Clean away the temporary references from recording objects
@@ -2957,13 +2962,11 @@ replay ()
      refs.  Hence we must stop using them before the GC can run.  */
   m_recording_ctxt->disassociate_from_playback ();
 
-  /* The builtins_manager, if any, is associated with the recording::context
+  /* The builtins_manager is associated with the recording::context
      and might be reused for future compiles on other playback::contexts,
      but its m_attributes array is not GTY-labeled and hence will become
      nonsense if the GC runs.  Purge this state.  */
-  builtins_manager *bm = get_builtins_manager ();
-  if (bm)
-    bm->finish_playback ();
+  bm->finish_playback ();
 
   timevar_pop (TV_JIT_REPLAY);
 

gcc/testsuite/jit.dg/test-trap.c

@@ -0,0 +1,59 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <stddef.h>
+
+#include "libgccjit.h"
+
+#include "harness.h"
+
+void
+create_code (gcc_jit_context *ctxt, void *user_data)
+{
+  /* Let's try to inject the equivalent of:
+
+     void
+     test_trap (void)
+     {
+       *((int *)0) = 42;
+     }
+  */
+  gcc_jit_type *void_type
+    = gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_VOID);
+  gcc_jit_type *int_type
+    = gcc_jit_context_get_type (ctxt, GCC_JIT_TYPE_INT);
+  gcc_jit_type *int_ptr_type
+    = gcc_jit_type_get_pointer (int_type);
+
+  /* Build the test_fn.  */
+  gcc_jit_function *func
+    = gcc_jit_context_new_function (ctxt, NULL,
+				    GCC_JIT_FUNCTION_EXPORTED,
+				    void_type,
+				    "test_trap",
+				    0, NULL,
+				    0);
+
+  gcc_jit_block *initial = gcc_jit_function_new_block (func, "initial");
+
+  gcc_jit_rvalue *null_ptr
+    = gcc_jit_context_new_rvalue_from_ptr (ctxt, int_ptr_type, NULL);
+
+  /* "*((int *)0) = 42;" */
+  gcc_jit_block_add_assignment (
+    initial, NULL,
+    gcc_jit_rvalue_dereference (null_ptr, NULL),
+    gcc_jit_context_new_rvalue_from_int (ctxt, int_type, 42));
+
+  gcc_jit_block_end_with_void_return (initial, NULL);
+}
+
+void
+verify_code (gcc_jit_context *ctxt, gcc_jit_result *result)
+{
+  typedef void (*fn_type) (void);
+  CHECK_NON_NULL (result);
+  fn_type test_array =
+    (fn_type)gcc_jit_result_get_code (result, "test_trap");
+  CHECK_NON_NULL (test_array);
+  /* Don't attempt to call it.  */
+}