[PATCH v2] ntdll: Properly save/restore FPU context in arm64 SIGUSR1 handler.

[Jinoh Kang]

Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=51996
Signed-off-by: Jinoh Kang <jinoh.kang.kr(a)gmail.com>
---

Notes:
    v1 -> v2: Edit commit message.

 dlls/ntdll/unix/signal_arm64.c | 116 +++++++++++++++++++--------------
 1 file changed, 66 insertions(+), 50 deletions(-)

diff --git a/dlls/ntdll/unix/signal_arm64.c b/dlls/ntdll/unix/signal_arm64.c
index a52e9bccc49..4e6a0872335 100644
--- a/dlls/ntdll/unix/signal_arm64.c
+++ b/dlls/ntdll/unix/signal_arm64.c
@@ -84,7 +84,7 @@ WINE_DEFAULT_DEBUG_CHANNEL(seh);
 # define FP_sig(context)            REGn_sig(29, context)    /* Frame pointer */
 # define LR_sig(context)            REGn_sig(30, context)    /* Link Register */
 
-static struct _aarch64_ctx *get_extended_sigcontext( ucontext_t *sigcontext, unsigned int magic )
+static struct _aarch64_ctx *get_extended_sigcontext( const ucontext_t *sigcontext, unsigned int magic )
 {
     struct _aarch64_ctx *ctx = (struct _aarch64_ctx *)sigcontext->uc_mcontext.__reserved;
     while ((char *)ctx < (char *)(&sigcontext->uc_mcontext + 1) && ctx->magic && ctx->size)
@@ -95,7 +95,7 @@ static struct _aarch64_ctx *get_extended_sigcontext( ucontext_t *sigcontext, uns
     return NULL;
 }
 
-static struct fpsimd_context *get_fpsimd_context( ucontext_t *sigcontext )
+static struct fpsimd_context *get_fpsimd_context( const ucontext_t *sigcontext )
 {
     return (struct fpsimd_context *)get_extended_sigcontext( sigcontext, FPSIMD_MAGIC );
 }
@@ -324,50 +324,12 @@ NTSTATUS CDECL unwind_builtin_dll( ULONG type, DISPATCHER_CONTEXT *dispatch, CON
 }
 
 
-/***********************************************************************
- *           save_context
- *
- * Set the register values from a sigcontext.
- */
-static void save_context( CONTEXT *context, const ucontext_t *sigcontext )
-{
-    DWORD i;
-
-    context->ContextFlags = (CONTEXT_FULL & ~CONTEXT_FLOATING_POINT) |
-                             CONTEXT_ARM64;
-    context->u.s.Fp = FP_sig(sigcontext);     /* Frame pointer */
-    context->u.s.Lr = LR_sig(sigcontext);     /* Link register */
-    context->Sp     = SP_sig(sigcontext);     /* Stack pointer */
-    context->Pc     = PC_sig(sigcontext);     /* Program Counter */
-    context->Cpsr   = PSTATE_sig(sigcontext); /* Current State Register */
-    for (i = 0; i <= 28; i++) context->u.X[i] = REGn_sig( i, sigcontext );
-}
-
-
-/***********************************************************************
- *           restore_context
- *
- * Build a sigcontext from the register values.
- */
-static void restore_context( const CONTEXT *context, ucontext_t *sigcontext )
-{
-    DWORD i;
-
-    FP_sig(sigcontext)     = context->u.s.Fp; /* Frame pointer */
-    LR_sig(sigcontext)     = context->u.s.Lr; /* Link register */
-    SP_sig(sigcontext)     = context->Sp;     /* Stack pointer */
-    PC_sig(sigcontext)     = context->Pc;     /* Program Counter */
-    PSTATE_sig(sigcontext) = context->Cpsr;   /* Current State Register */
-    for (i = 0; i <= 28; i++) REGn_sig( i, sigcontext ) = context->u.X[i];
-}
-
-
 /***********************************************************************
  *           save_fpu
  *
  * Set the FPU context from a sigcontext.
  */
-static void save_fpu( CONTEXT *context, ucontext_t *sigcontext )
+static void save_fpu( CONTEXT *context, const ucontext_t *sigcontext )
 {
 #ifdef linux
     struct fpsimd_context *fp = get_fpsimd_context( sigcontext );
@@ -391,23 +353,62 @@ static void save_fpu( CONTEXT *context, ucontext_t *sigcontext )
  *
  * Restore the FPU context to a sigcontext.
  */
-static void restore_fpu( struct syscall_frame *frame, ucontext_t *sigcontext )
+static void restore_fpu( const CONTEXT *context, ucontext_t *sigcontext )
 {
 #ifdef linux
     struct fpsimd_context *fp = get_fpsimd_context( sigcontext );
 
     if (!fp) return;
-    fp->fpcr = frame->fpcr;
-    fp->fpsr = frame->fpsr;
-    memcpy( fp->vregs, frame->v, sizeof(fp->vregs) );
+    fp->fpcr = context->Fpcr;
+    fp->fpsr = context->Fpsr;
+    memcpy( fp->vregs, context->V, sizeof(fp->vregs) );
 #elif defined(__APPLE__)
-    sigcontext->uc_mcontext->__ns.__fpcr = frame->fpcr;
-    sigcontext->uc_mcontext->__ns.__fpsr = frame->fpsr;
-    memcpy( sigcontext->uc_mcontext->__ns.__v, frame->v, sizeof(frame->v) );
+    sigcontext->uc_mcontext->__ns.__fpcr = context->Fpcr;
+    sigcontext->uc_mcontext->__ns.__fpsr = context->Fpsr;
+    memcpy( sigcontext->uc_mcontext->__ns.__v, context->V, sizeof(context->v) );
 #endif
 }
 
 
+/***********************************************************************
+ *           save_context
+ *
+ * Set the register values from a sigcontext.
+ */
+static void save_context( CONTEXT *context, const ucontext_t *sigcontext )
+{
+    DWORD i;
+
+    context->ContextFlags = CONTEXT_FULL | CONTEXT_ARM64;
+    context->u.s.Fp = FP_sig(sigcontext);     /* Frame pointer */
+    context->u.s.Lr = LR_sig(sigcontext);     /* Link register */
+    context->Sp     = SP_sig(sigcontext);     /* Stack pointer */
+    context->Pc     = PC_sig(sigcontext);     /* Program Counter */
+    context->Cpsr   = PSTATE_sig(sigcontext); /* Current State Register */
+    for (i = 0; i <= 28; i++) context->u.X[i] = REGn_sig( i, sigcontext );
+    save_fpu( context, sigcontext );
+}
+
+
+/***********************************************************************
+ *           restore_context
+ *
+ * Build a sigcontext from the register values.
+ */
+static void restore_context( const CONTEXT *context, ucontext_t *sigcontext )
+{
+    DWORD i;
+
+    FP_sig(sigcontext)     = context->u.s.Fp; /* Frame pointer */
+    LR_sig(sigcontext)     = context->u.s.Lr; /* Link register */
+    SP_sig(sigcontext)     = context->Sp;     /* Stack pointer */
+    PC_sig(sigcontext)     = context->Pc;     /* Program Counter */
+    PSTATE_sig(sigcontext) = context->Cpsr;   /* Current State Register */
+    for (i = 0; i <= 28; i++) REGn_sig( i, sigcontext ) = context->u.X[i];
+    restore_fpu( context, sigcontext );
+}
+
+
 /***********************************************************************
  *           signal_set_full_context
  */
@@ -632,7 +633,6 @@ static void setup_exception( ucontext_t *sigcontext, EXCEPTION_RECORD *rec )
 
     rec->ExceptionAddress = (void *)PC_sig(sigcontext);
     save_context( &context, sigcontext );
-    save_fpu( &context, sigcontext );
 
     status = send_debug_event( rec, &context, TRUE );
     if (status == DBG_CONTINUE || status == DBG_EXCEPTION_HANDLED)
@@ -1047,6 +1047,9 @@ static void usr2_handler( int signal, siginfo_t *siginfo, void *sigcontext )
     struct syscall_frame *frame = arm64_thread_data()->syscall_frame;
     ucontext_t *context = sigcontext;
     DWORD i;
+#ifdef linux
+    struct fpsimd_context *fp;
+#endif
 
     if (!is_inside_syscall( sigcontext )) return;
 
@@ -1056,7 +1059,20 @@ static void usr2_handler( int signal, siginfo_t *siginfo, void *sigcontext )
     PC_sig(context)     = frame->pc;
     PSTATE_sig(context) = frame->cpsr;
     for (i = 0; i <= 28; i++) REGn_sig( i, context ) = frame->x[i];
-    restore_fpu( frame, context );
+
+#ifdef linux
+    fp = get_fpsimd_context( sigcontext );
+    if (fp)
+    {
+        fp->fpcr = frame->fpcr;
+        fp->fpsr = frame->fpsr;
+        memcpy( fp->vregs, frame->v, sizeof(fp->vregs) );
+    }
+#elif defined(__APPLE__)
+    sigcontext->uc_mcontext->__ns.__fpcr = frame->fpcr;
+    sigcontext->uc_mcontext->__ns.__fpsr = frame->fpsr;
+    memcpy( sigcontext->uc_mcontext->__ns.__v, frame->v, sizeof(frame->v) );
+#endif
 }
 
 
-- 
2.33.1