Initial checkin of GCC 4.9.0 from trunk (r208799).

Change-Id: I48a3c08bb98542aa215912a75f03c0890e497dba

1 files changed, 185 insertions, 0 deletions

diff --git a/gcc-4.9/libjava/include/x86_64-signal.h b/gcc-4.9/libjava/include/x86_64-signal.h
new file mode 100644
index 000000000..12383b548
--- /dev/null
+++ b/gcc-4.9/libjava/include/x86_64-signal.h
@@ -0,0 +1,185 @@
+// x86_64-signal.h - Catch runtime signals and turn them into exceptions
+// on an x86_64 based GNU/Linux system.
+
+/* Copyright (C) 2003, 2006, 2007, 2012  Free Software Foundation
+
+   This file is part of libgcj.
+
+This software is copyrighted work licensed under the terms of the
+Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
+details.  */
+
+
+#ifdef __x86_64__
+
+#ifndef JAVA_SIGNAL_H
+#define JAVA_SIGNAL_H 1
+
+#include <signal.h>
+#include <sys/syscall.h>
+
+#define HANDLE_SEGV 1
+#define HANDLE_FPE 1
+
+#define SIGNAL_HANDLER(_name)					\
+static void _Jv_##_name (int, siginfo_t *,			\
+			 void *_p __attribute__ ((__unused__)))
+
+#define HANDLE_DIVIDE_OVERFLOW						\
+do									\
+{									\
+  struct ucontext *_uc = (struct ucontext *)_p;				\
+  gregset_t &_gregs = _uc->uc_mcontext.gregs;				\
+  unsigned char *_rip = (unsigned char *)_gregs[REG_RIP];		\
+									\
+  /* According to the JVM spec, "if the dividend is the negative	\
+   * integer of largest possible magnitude for the type and the		\
+   * divisor is -1, then overflow occurs and the result is equal to	\
+   * the dividend.  Despite the overflow, no exception occurs".		\
+									\
+   * We handle this by inspecting the instruction which generated the	\
+   * signal and advancing ip to point to the following instruction.	\
+   * As the instructions are variable length it is necessary to do a	\
+   * little calculation to figure out where the following instruction	\
+   * actually is.							\
+									\
+   */									\
+									\
+  bool _is_64_bit = false;						\
+									\
+  /* Skip 67h address size prefix.  */					\
+  if (_rip[0] == 0x67)							\
+    _rip++;								\
+									\
+  if ((_rip[0] & 0xf0) == 0x40)  /* REX byte present.  */		\
+    {									\
+      unsigned char _rex = _rip[0] & 0x0f;				\
+      _is_64_bit = (_rex & 0x08) != 0;					\
+      _rip++;								\
+    }									\
+									\
+  /* Detect a signed division of Integer.MIN_VALUE or Long.MIN_VALUE.  */ \
+  if (_rip[0] == 0xf7)							\
+    {									\
+      bool _min_value_dividend = false;					\
+      unsigned char _modrm = _rip[1];					\
+									\
+      if (((_modrm >> 3) & 7) == 7)					\
+	{								\
+	  if (_is_64_bit)						\
+	    _min_value_dividend =					\
+	      _gregs[REG_RAX] == (greg_t)0x8000000000000000ULL;		\
+	  else								\
+	    _min_value_dividend =					\
+	      (_gregs[REG_RAX] & 0xffffffff) == (greg_t)0x80000000ULL;	\
+	}								\
+									\
+      if (_min_value_dividend)						\
+	{								\
+	  unsigned char _rm = _modrm & 7;				\
+	  _gregs[REG_RDX] = 0; /* the remainder is zero */		\
+	  switch (_modrm >> 6)						\
+	    {								\
+	    case 0:  /* register indirect */				\
+	      if (_rm == 5)   /* 32-bit displacement */			\
+		_rip += 4;						\
+	      if (_rm == 4)  /* A SIB byte follows the ModR/M byte */	\
+		_rip += 1;						\
+	      break;							\
+	    case 1:  /* register indirect + 8-bit displacement */	\
+	      _rip += 1;						\
+	      if (_rm == 4)  /* A SIB byte follows the ModR/M byte */	\
+		_rip += 1;						\
+	      break;							\
+	    case 2:  /* register indirect + 32-bit displacement */	\
+	      _rip += 4;						\
+	      if (_rm == 4)  /* A SIB byte follows the ModR/M byte */	\
+		_rip += 1;						\
+	      break;							\
+	    case 3:							\
+	      break;							\
+	    }								\
+	  _rip += 2;							\
+	  _gregs[REG_RIP] = (greg_t)_rip;				\
+	  return;							\
+	}								\
+    }									\
+}									\
+while (0)
+
+extern "C" 
+{
+  struct kernel_sigaction 
+  {
+    void (*k_sa_sigaction)(int,siginfo_t *,void *);
+    unsigned long k_sa_flags;
+    void (*k_sa_restorer) (void);
+    sigset_t k_sa_mask;
+  };
+}
+
+#define MAKE_THROW_FRAME(_exception)
+
+#define RESTORE(name, syscall) RESTORE2 (name, syscall)
+#define RESTORE2(name, syscall)			\
+asm						\
+  (						\
+   ".text\n"					\
+   ".byte 0  # Yes, this really is necessary\n" \
+   ".align 16\n"				\
+   "__" #name ":\n"				\
+   "	movq $" #syscall ", %rax\n"		\
+   "	syscall\n"				\
+   );
+
+/* The return code for realtime-signals.  */
+RESTORE (restore_rt, __NR_rt_sigreturn)
+void restore_rt (void) asm ("__restore_rt")
+  __attribute__ ((visibility ("hidden")));
+
+#define INIT_SEGV						\
+do								\
+  {								\
+    struct kernel_sigaction act;				\
+    act.k_sa_sigaction = _Jv_catch_segv;			\
+    sigemptyset (&act.k_sa_mask);				\
+    act.k_sa_flags = SA_SIGINFO|0x4000000;			\
+    act.k_sa_restorer = restore_rt;				\
+    syscall (SYS_rt_sigaction, SIGSEGV, &act, NULL, _NSIG / 8);	\
+  }								\
+while (0)  
+
+#define INIT_FPE						\
+do								\
+  {								\
+    struct kernel_sigaction act;				\
+    act.k_sa_sigaction = _Jv_catch_fpe;				\
+    sigemptyset (&act.k_sa_mask);				\
+    act.k_sa_flags = SA_SIGINFO|0x4000000;			\
+    act.k_sa_restorer = restore_rt;				\
+    syscall (SYS_rt_sigaction, SIGFPE, &act, NULL, _NSIG / 8);	\
+  }								\
+while (0)  
+
+/* You might wonder why we use syscall(SYS_sigaction) in INIT_FPE
+ * instead of the standard sigaction().  This is necessary because of
+ * the shenanigans above where we increment the PC saved in the
+ * context and then return.  This trick will only work when we are
+ * called _directly_ by the kernel, because linuxthreads wraps signal
+ * handlers and its wrappers do not copy the sigcontext struct back
+ * when returning from a signal handler.  If we return from our divide
+ * handler to a linuxthreads wrapper, we will lose the PC adjustment
+ * we made and return to the faulting instruction again.  Using
+ * syscall(SYS_sigaction) causes our handler to be called directly
+ * by the kernel, bypassing any wrappers.  */
+
+#endif /* JAVA_SIGNAL_H */
+
+#else /* __x86_64__ */
+
+/* This is for the 32-bit subsystem on x86-64.  */
+
+#define sigcontext_struct sigcontext
+#include <java-signal-aux.h>
+
+#endif /* __x86_64__ */