Alexandre Julliard : ntdll: Use the correct structure for non-volatile registers on ARM.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 0c35e9adce90562ecc5bf9869161e71a105a4b03
URL:    https://gitlab.winehq.org/wine/wine/-/commit/0c35e9adce90562ecc5bf9869161e71...

Author: Alexandre Julliard 
Date:   Mon Mar  4 13:20:49 2024 +0100

ntdll: Use the correct structure for non-volatile registers on ARM.

---

dlls/ntdll/signal_arm.c      | 27 ++++++++++++++++++++++-----
 dlls/ntdll/tests/exception.c | 14 +++++++++++++-
 2 files changed, 35 insertions(+), 6 deletions(-)

diff --git a/dlls/ntdll/signal_arm.c b/dlls/ntdll/signal_arm.c
index c7a036cefc0..4ae637fdcc4 100644
--- a/dlls/ntdll/signal_arm.c
+++ b/dlls/ntdll/signal_arm.c
@@ -69,6 +69,18 @@ static void dump_scope_table( ULONG base, const SCOPE_TABLE *table )
                base + table->ScopeRecord[i].JumpTarget );
 }

+/* undocumented, copied from the corresponding ARM64 structure */
+typedef union _DISPATCHER_CONTEXT_NONVOLREG_ARM
+{
+    BYTE  Buffer[8 * sizeof(DWORD) + 8 * sizeof(double)];
+    struct
+    {
+        DWORD  GpNvRegs[8];
+        double FpNvRegs[8];
+    } DUMMYSTRUCTNAME;
+} DISPATCHER_CONTEXT_NONVOLREG_ARM;
+
+
 /*******************************************************************
  *         syscalls
  */
@@ -116,6 +128,7 @@ __ASM_GLOBAL_FUNC( RtlCaptureContext,
  */
 static NTSTATUS virtual_unwind( ULONG type, DISPATCHER_CONTEXT *dispatch, CONTEXT *context )
 {
+    DISPATCHER_CONTEXT_NONVOLREG_ARM *nonvol_regs;
     DWORD pc = context->Pc;

dispatch->ScopeIndex = 0;
@@ -123,6 +136,10 @@ static NTSTATUS virtual_unwind( ULONG type, DISPATCHER_CONTEXT *dispatch, CONTEX
     dispatch->ControlPcIsUnwound = (context->ContextFlags & CONTEXT_UNWOUND_TO_CALL) != 0;
     if (dispatch->ControlPcIsUnwound) pc -= 2;

+    nonvol_regs = (DISPATCHER_CONTEXT_NONVOLREG_ARM *)dispatch->NonVolatileRegisters;
+    memcpy( nonvol_regs->GpNvRegs, &context->R4, sizeof(nonvol_regs->GpNvRegs) );
+    memcpy( nonvol_regs->FpNvRegs, &context->D[8], sizeof(nonvol_regs->FpNvRegs) );
+
     dispatch->FunctionEntry = RtlLookupFunctionEntry( pc, (DWORD_PTR *)&dispatch->ImageBase,
                                                       dispatch->HistoryTable );
     if (RtlVirtualUnwind2( type, dispatch->ImageBase, pc, dispatch->FunctionEntry, context,
@@ -297,17 +314,17 @@ static DWORD call_teb_handler( EXCEPTION_RECORD *rec, CONTEXT *context, DISPATCH
 NTSTATUS call_seh_handlers( EXCEPTION_RECORD *rec, CONTEXT *orig_context )
 {
     EXCEPTION_REGISTRATION_RECORD *teb_frame = NtCurrentTeb()->Tib.ExceptionList;
+    DISPATCHER_CONTEXT_NONVOLREG_ARM nonvol_regs;
     UNWIND_HISTORY_TABLE table;
     DISPATCHER_CONTEXT dispatch;
-    CONTEXT context, prev_context;
+    CONTEXT context;
     NTSTATUS status;

context = *orig_context;
     dispatch.TargetPc      = 0;
     dispatch.ContextRecord = &context;
     dispatch.HistoryTable  = &table;
-    prev_context = context;
-    dispatch.NonVolatileRegisters = (BYTE *)&prev_context.R4;
+    dispatch.NonVolatileRegisters = nonvol_regs.Buffer;

for (;;)
     {
@@ -387,7 +404,6 @@ NTSTATUS call_seh_handlers( EXCEPTION_RECORD *rec, CONTEXT *orig_context )
         }

if (context.Sp == (DWORD)NtCurrentTeb()->Tib.StackBase) break;
-        prev_context = context;
     }
     return STATUS_UNHANDLED_EXCEPTION;
 }
@@ -541,6 +557,7 @@ void WINAPI RtlUnwindEx( PVOID end_frame, PVOID target_ip, EXCEPTION_RECORD *rec
                          PVOID retval, CONTEXT *context, UNWIND_HISTORY_TABLE *table )
 {
     EXCEPTION_REGISTRATION_RECORD *teb_frame = NtCurrentTeb()->Tib.ExceptionList;
+    DISPATCHER_CONTEXT_NONVOLREG_ARM nonvol_regs;
     EXCEPTION_RECORD record;
     DISPATCHER_CONTEXT dispatch;
     CONTEXT new_context;
@@ -572,7 +589,7 @@ void WINAPI RtlUnwindEx( PVOID end_frame, PVOID target_ip, EXCEPTION_RECORD *rec
     dispatch.TargetPc         = (ULONG_PTR)target_ip;
     dispatch.ContextRecord    = context;
     dispatch.HistoryTable     = table;
-    dispatch.NonVolatileRegisters = (BYTE *)&context->R4;
+    dispatch.NonVolatileRegisters = nonvol_regs.Buffer;

for (;;)
     {
diff --git a/dlls/ntdll/tests/exception.c b/dlls/ntdll/tests/exception.c
index e6add6dd60e..d33564e4800 100644
--- a/dlls/ntdll/tests/exception.c
+++ b/dlls/ntdll/tests/exception.c
@@ -6037,8 +6037,20 @@ static DWORD WINAPI rtlraiseexception_teb_handler( EXCEPTION_RECORD *rec,
 }

static DWORD WINAPI rtlraiseexception_handler( EXCEPTION_RECORD *rec, void *frame,
-                                               CONTEXT *context, void *dispatcher )
+                                               CONTEXT *context, DISPATCHER_CONTEXT *dispatcher )
 {
+    ULONG *nonvol_regs = (void *)dispatcher->NonVolatileRegisters;
+    int i;
+
+    for (i = 0; i < 8; i++)
+        ok( nonvol_regs[i] == ((ULONG *)&context->R4)[i],
+            "wrong non volatile reg r%u %lx / %lx\n", i + 4,
+            nonvol_regs[i], ((ULONG *)&context->R4)[i] );
+    for (i = 0; i < 8; i++)
+        ok( ((ULONGLONG *)(nonvol_regs + 8))[i] == context->D[i + 8],
+            "wrong non volatile reg d%u %I64x / %I64x\n", i + 8,
+            ((ULONGLONG *)(nonvol_regs + 8))[i], context->D[i + 8] );
+
     rtlraiseexception_handler_called = 1;
     rtlraiseexception_handler_(rec, frame, context, dispatcher, FALSE);
     return ExceptionContinueSearch;