[Audit] round 9: generalize JIT-entry probe to PC-configurable cvar

Replace the round-7 hardcoded `current_guest_function_ == 0x824F7800`
gate with a runtime cvar `audit_jit_prolog_pc` (uint32, 0 = disabled).
The cvar names the guest entry PC at which the x64 emitter inserts a
CallNative to the prolog probe; the probe now dumps the active PC in
each log line so multiple instrumentation campaigns can share output.

Renames `audit_log_sub824F7800_args` (cvar) and `AuditLogSub824F7800Args`
(host function) — the round-7 sub_824F7800-specific cvar and function
are deleted, not left dormant. The `audit_handle_lifecycle` cvar and
its existing AUDIT-HLC probe sites in xboxkrnl_threading.cc /
kernel_state.cc are untouched.

Validated by audit-059 round 9: with `--audit_jit_prolog_pc=0x821B55D8`
the silph WorkerCtx-init chain entry fires 1× in canary at tid=6
lr=0x82172D8C (call site at sub_82172BA0+0x1E8 `bctrl`, the virtual
dispatch through vtable slot 6 that statically-blind xref-walkers
cannot enumerate).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/xenia/cpu/backend/x64/x64_emitter.cc

@@ -41,6 +41,14 @@
 
 DEFINE_bool(debugprint_trap_log, false,
             "Log debugprint traps to the active debugger", "CPU");
+DEFINE_uint32(audit_jit_prolog_pc, 0,
+              "Guest function entry PC at which to emit one XELOGKERNEL line "
+              "per JIT-compiled entry. When non-zero, the x64 emitter inserts "
+              "a CallNative to AuditLogJitPrologArgs at the start of the JIT "
+              "body of the matching guest function. Dumps r3..r10, LR, and 64 "
+              "bytes at host(r3). Zero (default) disables the probe. Audit-059 "
+              "round 7+ JIT-prolog probe — generic PC-configurable variant.",
+              "Auditing");
 DEFINE_bool(ignore_undefined_externs, true,
             "Don't exit when an undefined extern is called.", "CPU");
 DEFINE_bool(emit_source_annotations, false,
@@ -270,6 +278,17 @@ bool X64Emitter::Emit(HIRBuilder* builder, EmitFunctionInfo& func_info) {
   count on no other code modifying it. mov(GetMembaseReg(),
       qword[GetContextReg() + offsetof(ppc::PPCContext, virtual_membase)]);
   */
+  // Audit-059: PC-configurable JIT-prolog probe. Runtime-gated on the cvar
+  // audit_jit_prolog_pc (uint32; 0 disables). When non-zero and the current
+  // guest function's entry PC matches, emit a single CallNative to
+  // AuditLogJitPrologArgs that dumps r3..r10, LR, and 64 bytes at host(r3).
+  // Emits *before* any body instruction runs, so r3..r10 / LR in PPCContext
+  // still reflect the caller's args (no LOAD/STORE_CONTEXT has executed yet).
+  if (cvars::audit_jit_prolog_pc != 0u &&
+      current_guest_function_ == cvars::audit_jit_prolog_pc) {
+    extern uint64_t AuditLogJitPrologArgs(void* raw_context, uint64_t arg0);
+    CallNative(AuditLogJitPrologArgs, 0);
+  }
   // Body.
   auto block = builder->first_block();
   synchronize_stack_on_next_instruction_ = false;
@@ -438,6 +457,55 @@ uint64_t TrapDebugBreak(void* raw_context, uint64_t address) {
   return 0;
 }
 
+// Audit-059 JIT-prolog probe: dump r3..r10, LR, and 64 bytes at host(r3)
+// when the guest hits the JIT-compiled entry of the function whose entry PC
+// matches cvars::audit_jit_prolog_pc. Generic PC-configurable variant of the
+// round-7 sub_824F7800 hook. The hook logs the current guest PC so multiple
+// instrumentation campaigns can share log output.
+uint64_t AuditLogJitPrologArgs(void* raw_context, uint64_t /*unused*/) {
+  auto* ctx = reinterpret_cast<ppc::PPCContext_s*>(raw_context);
+  uint32_t pc = static_cast<uint32_t>(cvars::audit_jit_prolog_pc);
+  uint32_t r3 = static_cast<uint32_t>(ctx->r[3]);
+  uint32_t r4 = static_cast<uint32_t>(ctx->r[4]);
+  uint32_t r5 = static_cast<uint32_t>(ctx->r[5]);
+  uint32_t r6 = static_cast<uint32_t>(ctx->r[6]);
+  uint32_t r7 = static_cast<uint32_t>(ctx->r[7]);
+  uint32_t r8 = static_cast<uint32_t>(ctx->r[8]);
+  uint32_t r9 = static_cast<uint32_t>(ctx->r[9]);
+  uint32_t r10 = static_cast<uint32_t>(ctx->r[10]);
+  uint32_t lr = static_cast<uint32_t>(ctx->lr);
+
+  uint32_t tid = ctx->thread_state ? ctx->thread_state->thread_id() : 0u;
+
+  XELOGKERNEL(
+      "AUDIT-HLC JitProlog pc={:08X} tid={:08X} r3={:08X} r4={:08X} r5={:08X} "
+      "r6={:08X} r7={:08X} r8={:08X} r9={:08X} r10={:08X} lr={:08X}",
+      pc, tid, r3, r4, r5, r6, r7, r8, r9, r10, lr);
+
+  // Dump 64 bytes at host(r3) if r3 looks like a plausible guest VA.
+  if (r3 >= 0x10000 && r3 < 0xE0000000) {
+    uint8_t* host = ctx->TranslateVirtual(r3);
+    if (host) {
+      for (uint32_t off = 0; off < 0x40; off += 16) {
+        uint32_t d0 = xe::load_and_swap<uint32_t>(host + off + 0);
+        uint32_t d1 = xe::load_and_swap<uint32_t>(host + off + 4);
+        uint32_t d2 = xe::load_and_swap<uint32_t>(host + off + 8);
+        uint32_t d3 = xe::load_and_swap<uint32_t>(host + off + 12);
+        XELOGKERNEL(
+            "AUDIT-HLC JitProlog pc={:08X} r3+{:02X}: {:08X} {:08X} {:08X} "
+            "{:08X}",
+            pc, off, d0, d1, d2, d3);
+      }
+    } else {
+      XELOGKERNEL("AUDIT-HLC JitProlog pc={:08X} r3 translate failed", pc);
+    }
+  } else {
+    XELOGKERNEL("AUDIT-HLC JitProlog pc={:08X} r3 out of VA range, skipping dump",
+                pc);
+  }
+  return 0;
+}
+
 void X64Emitter::Trap(uint16_t trap_type) {
   switch (trap_type) {
     case 20:

src/xenia/kernel/kernel_flags.cc

@@ -14,3 +14,7 @@ DEFINE_bool(headless, false,
             "UI");
 DEFINE_bool(log_high_frequency_kernel_calls, false,
             "Log kernel calls with the kHighFrequency tag.", "Logging");
+DEFINE_bool(audit_handle_lifecycle, false,
+            "Emit XELOGKERNEL on Event/Semaphore/Wait lifecycle "
+            "(create/set/wait/complete). Audit oracle probe — off by default.",
+            "Auditing");

src/xenia/kernel/kernel_flags.h

@@ -13,5 +13,6 @@
 
 DECLARE_bool(headless);
 DECLARE_bool(log_high_frequency_kernel_calls);
+DECLARE_bool(audit_handle_lifecycle);
 
 #endif  // XENIA_KERNEL_KERNEL_FLAGS_H_

src/xenia/kernel/kernel_state.cc

@@ -15,6 +15,7 @@
 #include "xenia/base/logging.h"
 #include "xenia/emulator.h"
 #include "xenia/hid/input_system.h"
+#include "xenia/kernel/kernel_flags.h"
 #include "xenia/kernel/user_module.h"
 #include "xenia/kernel/util/shim_utils.h"
 #include "xenia/kernel/xboxkrnl/xboxkrnl_memory.h"
@@ -1373,6 +1374,13 @@ void KernelState::EmulateCPInterruptDPC(uint32_t interrupt_callback,
     return;
   }
 
+  if (cvars::audit_handle_lifecycle) {
+    XELOGKERNEL(
+        "AUDIT-HLC EmulateCPInterruptDPC callback={:08X} data={:08X} source={} "
+        "cpu={}",
+        interrupt_callback, interrupt_callback_data, source, cpu);
+  }
+
   auto thread = kernel::XThread::GetCurrentThread();
   assert_not_null(thread);
 

src/xenia/kernel/xboxkrnl/xboxkrnl_threading.cc

@@ -8,10 +8,12 @@
  */
 
 #include "xenia/kernel/xboxkrnl/xboxkrnl_threading.h"
+#include <atomic>
 #include "xenia/base/atomic.h"
 #include "xenia/base/clock.h"
 #include "xenia/base/platform.h"
 #include "xenia/cpu/processor.h"
+#include "xenia/kernel/kernel_flags.h"
 #include "xenia/kernel/util/shim_utils.h"
 #include "xenia/kernel/xboxkrnl/xboxkrnl_private.h"
 #include "xenia/kernel/xsemaphore.h"
@@ -22,6 +24,9 @@ namespace xe {
 namespace kernel {
 namespace xboxkrnl {
 
+// AUDIT-HLC: one-shot guard for silph::WorkerCtx context dump (round5).
+static std::atomic<bool> g_audit_silph_ctx_dumped{false};
+
 // r13 + 0x100: pointer to thread local state
 // Thread local state:
 //   0x058: kernel time
@@ -547,6 +552,48 @@ uint32_t xeKeSetEvent(X_KEVENT* event_ptr, uint32_t increment, uint32_t wait) {
 
 dword_result_t KeSetEvent_entry(pointer_t<X_KEVENT> event_ptr,
                                 dword_t increment, dword_t wait) {
+  if (cvars::audit_handle_lifecycle) {
+    uint32_t lr = static_cast<uint32_t>(cpu::ThreadState::Get()->context()->lr);
+    XELOGKERNEL("AUDIT-HLC KeSetEvent guest_ptr={:08X} lr={:08X}",
+                uint32_t(event_ptr.guest_address()), lr);
+    // AUDIT-HLC round5: one-shot hexdump of the silph::WorkerCtx context when
+    // KeSetEvent first fires into the silph UI PKEVENT cluster
+    // (0xBCE25214/24/34/44 in current builds; widened a bit for allocator
+    // drift). Used by iterate 2.BF context-replication.
+    uint32_t ev_addr = uint32_t(event_ptr.guest_address());
+    if (ev_addr >= 0xBCE25200 && ev_addr < 0xBCE25300) {
+      if (!g_audit_silph_ctx_dumped.exchange(true)) {
+        // Events live at ctx+0x54, +0x64, +0x74, +0x84 (16-byte stride).
+        // Compute ctx_base assuming the canonical layout (lowest event at
+        // ctx+0x54 → ctx_base = 0xBCE251C0 when ev_addr == 0xBCE25214).
+        uint32_t event_offset_in_ctx = ev_addr - 0xBCE251C0;
+        uint32_t ctx_base = ev_addr - event_offset_in_ctx;
+        auto* ctx = cpu::ThreadState::Get()->context();
+        uint8_t* host = ctx->TranslateVirtual(ctx_base);
+        XELOGKERNEL(
+            "AUDIT-HLC silph_ctx_dump ctx_base={:08X} (event {:08X} at +{:02X})",
+            ctx_base, ev_addr, event_offset_in_ctx);
+        for (uint32_t off = 0; off < 0x300; off += 16) {
+          uint32_t d0 = xe::load_and_swap<uint32_t>(host + off + 0);
+          uint32_t d1 = xe::load_and_swap<uint32_t>(host + off + 4);
+          uint32_t d2 = xe::load_and_swap<uint32_t>(host + off + 8);
+          uint32_t d3 = xe::load_and_swap<uint32_t>(host + off + 12);
+          XELOGKERNEL("AUDIT-HLC DUMP {:08X}: {:08X} {:08X} {:08X} {:08X}",
+                      ctx_base + off, d0, d1, d2, d3);
+        }
+        XELOGKERNEL("AUDIT-HLC silph_ctx event-slots:");
+        for (uint32_t i = 0; i < 8; ++i) {
+          uint32_t ev_off = 0x54 + i * 0x10;
+          uint32_t hdr = xe::load_and_swap<uint32_t>(host + ev_off + 0);
+          uint32_t state = xe::load_and_swap<uint32_t>(host + ev_off + 4);
+          XELOGKERNEL(
+              "AUDIT-HLC   slot[{}] off=+{:02X} addr={:08X} hdr={:08X} "
+              "state={:08X}",
+              i, ev_off, ctx_base + ev_off, hdr, state);
+        }
+      }
+    }
+  }
   return xeKeSetEvent(event_ptr, increment, wait);
 }
 DECLARE_XBOXKRNL_EXPORT2(KeSetEvent, kThreading, kImplemented, kHighFrequency);
@@ -604,6 +651,14 @@ dword_result_t NtCreateEvent_entry(
   if (handle_ptr) {
     *handle_ptr = ev->handle();
   }
+  if (cvars::audit_handle_lifecycle) {
+    uint32_t lr = static_cast<uint32_t>(cpu::ThreadState::Get()->context()->lr);
+    XELOGKERNEL(
+        "AUDIT-HLC NtCreateEvent handle={:08X} type={} initial_state={} "
+        "lr={:08X}",
+        handle_ptr ? uint32_t(*handle_ptr) : 0u, uint32_t(event_type),
+        uint32_t(initial_state), lr);
+  }
   return X_STATUS_SUCCESS;
 }
 DECLARE_XBOXKRNL_EXPORT1(NtCreateEvent, kThreading, kImplemented);
@@ -629,6 +684,11 @@ uint32_t xeNtSetEvent(uint32_t handle, xe::be<uint32_t>* previous_state_ptr) {
 }
 
 dword_result_t NtSetEvent_entry(dword_t handle, lpdword_t previous_state_ptr) {
+  if (cvars::audit_handle_lifecycle) {
+    uint32_t lr = static_cast<uint32_t>(cpu::ThreadState::Get()->context()->lr);
+    XELOGKERNEL("AUDIT-HLC NtSetEvent handle={:08X} lr={:08X}",
+                uint32_t(handle), lr);
+  }
   return xeNtSetEvent(handle, previous_state_ptr);
 }
 DECLARE_XBOXKRNL_EXPORT2(NtSetEvent, kThreading, kImplemented, kHighFrequency);
@@ -1003,9 +1063,43 @@ dword_result_t NtWaitForSingleObjectEx_entry(dword_t object_handle,
                                              dword_t wait_mode,
                                              dword_t alertable,
                                              lpqword_t timeout_ptr) {
+  uint32_t lr_enter = 0;
+  uint32_t guest_lr = 0;
+  if (cvars::audit_handle_lifecycle) {
+    auto* ctx = cpu::ThreadState::Get()->context();
+    lr_enter = static_cast<uint32_t>(ctx->lr);
+    // Walk one PPC stack frame up from the wait wrapper's frame to recover
+    // the GUEST caller's LR (lr_enter is just the kernel-internal wait
+    // wrapper's return address; we want the function that called *it*).
+    // Xbox 360 PPC convention: prologue stores caller's LR at [old_sp - 8]
+    // *before* bumping r1 to the new frame, so from any frame, the LR saved
+    // by that frame's prologue lives at (back_chain - 8). See xenia-rs
+    // walk_guest_back_chain in crates/xenia-kernel/src/state.rs.
+    uint32_t sp = static_cast<uint32_t>(ctx->r[1]);
+    uint32_t back1 = xe::load_and_swap<uint32_t>(ctx->TranslateVirtual(sp));
+    if (back1) {
+      uint32_t back2 =
+          xe::load_and_swap<uint32_t>(ctx->TranslateVirtual(back1));
+      if (back2) {
+        guest_lr = xe::load_and_swap<uint32_t>(
+            ctx->TranslateVirtual(back2 - 8));
+      }
+    }
+    XELOGKERNEL(
+        "AUDIT-HLC NtWaitForSingleObjectEx handle={:08X} alertable={} "
+        "lr={:08X} guest_lr={:08X}",
+        uint32_t(object_handle), uint32_t(alertable), lr_enter, guest_lr);
+  }
   uint64_t timeout = timeout_ptr ? static_cast<uint64_t>(*timeout_ptr) : 0u;
-  return NtWaitForSingleObjectEx(object_handle, wait_mode, alertable,
-                                 timeout_ptr ? &timeout : nullptr);
+  uint32_t result = NtWaitForSingleObjectEx(object_handle, wait_mode, alertable,
+                                            timeout_ptr ? &timeout : nullptr);
+  if (cvars::audit_handle_lifecycle) {
+    XELOGKERNEL(
+        "AUDIT-HLC NtWaitForSingleObjectEx_done handle={:08X} result={:08X} "
+        "lr={:08X} guest_lr={:08X}",
+        uint32_t(object_handle), result, lr_enter, guest_lr);
+  }
+  return result;
 }
 DECLARE_XBOXKRNL_EXPORT3(NtWaitForSingleObjectEx, kThreading, kImplemented,
                          kBlocking, kHighFrequency);